@article{MTMT:34586796, title = {Sleep is Essential for Mental Health: Potential Role of Slow Oscillations}, url = {https://m2.mtmt.hu/api/publication/34586796}, author = {Aquino, Giulia and Alfi, Gaspare and Riemann, Dieter and Laurino, Marco and Menicucci, Danilo and Piarulli, Andrea and Palagini, Laura and Gemignani, Angelo}, doi = {10.1007/s40675-024-00277-w}, journal-iso = {CURR SLEEP MED REP}, journal = {CURRENT SLEEP MEDICINE REPORTS}, unique-id = {34586796}, issn = {2198-6401}, abstract = {Purpose of ReviewSleep is a physiological process characterized by a crucial interaction between behavioural and neurobiological aspects, thereby directly influencing mental functionality. The present work aims at providing an overview of the structure, topological distribution, and functions of the sleep slow oscillation (< 1 Hz), and at attempting to unveil how the mechanisms underlying its properties are altered in several mental disorders. Recent FindingsSlow wave sleep and especially the sleep slow oscillation appear to regulate essential mechanisms at the basis of neuronal and synaptic health, such as an efficient functional connectivity, brain plasticity, memory consolidation, metabolic clearance, and sleep maintenance. Alterations of these functions can be observed at various levels in a wide range of mental disorders, ranging from insomnia to overt psychiatric disorders. SummaryWe propose a guidance for research and clinical practice related to the sleep slow oscillation, considering the lack of clinical emphasis on this wave and highlighting the potential benefits of its direct non-invasive modulation. In this framework, we propose that targeting insomnia would be crucial for mental health by regulating the sleep slow oscillation.}, keywords = {slow wave sleep; clinical practice; neural plasticity; mental health; functional connectivity; Sleep slow oscillation}, year = {2024} } @article{MTMT:34479998, title = {Electrode Development for Epilepsy Diagnosis and Treatment}, url = {https://m2.mtmt.hu/api/publication/34479998}, author = {Paulk, A.C. and Salami, P. and Zelmann, R. and Cash, S.S.}, doi = {10.1016/j.nec.2023.09.003}, journal-iso = {NEUROSURG CLIN N AM}, journal = {NEUROSURGERY CLINICS OF NORTH AMERICA}, volume = {35}, unique-id = {34479998}, issn = {1042-3680}, year = {2024}, eissn = {1558-1349}, pages = {135-149} } @article{MTMT:34244112, title = {Adaptation Shapes Local Cortical Reactivity: From Bifurcation Diagram and Simulations to Human Physiological and Pathological Responses}, url = {https://m2.mtmt.hu/api/publication/34244112}, author = {Cattani, Anna and Galluzzi, Andrea and Fecchio, Matteo and Pigorini, Andrea and Mattia, Maurizio and Massimini, Marcello}, doi = {10.1523/ENEURO.0435-22.2023}, journal-iso = {ENEURO}, journal = {ENEURO}, volume = {10}, unique-id = {34244112}, abstract = {Human studies employing intracerebral and transcranial perturbations suggest that the input-output properties of cortical circuits are dramatically affected during sleep in healthy subjects as well as in awake patients with multifocal and focal brain injury. In all these conditions, cortical circuits react to direct stimulation with an initial activation followed by suppression of activity (Off-period) that disrupts the build-up of sustained causal interactions typically observed in healthy wakefulness. The transition to this stereotypical response has important clinical implications, being associated with loss of consciousness or loss of functions. Here, we provide a mechanistic explanation of these findings by means of simulations of a cortical-like module endowed with activity-dependent adaptation and mean-field theory. First, we show that fundamental aspects of the local responses elicited in humans by direct cortical stimulation can be replicated by systematically varying the relationships between adaptation strength and excitation level in the network. Then, we reveal a region in the adaptation-excitation parameter space of crucial relevance for both physiological and pathologic conditions, where spontaneous activity and responses to perturbation diverge in their ability to reveal Off-periods. Finally, we substantiate through simulations of connected cortical-like modules the role of adaptation mechanisms in preventing cortical neurons from engaging in reciprocal causal interactions, as suggested by empirical studies. These modeling results provide a general theoretical framework and a mechanistic interpretation for a body of neurophysiological measurements that bears critical relevance for physiological states as well as for the assessment and rehabilitation of brain-injured patients.}, keywords = {Bifurcation theory; cortical network model; cortical bistability; off-period}, year = {2023}, eissn = {2373-2822}, orcid-numbers = {Cattani, Anna/0000-0003-2317-1737; Fecchio, Matteo/0000-0002-0347-8531; Pigorini, Andrea/0000-0002-1856-3413; Mattia, Maurizio/0000-0002-2356-4509} } @article{MTMT:34229256, title = {Closed-loop auditory stimulation of sleep slow oscillations: Basic principles and best practices}, url = {https://m2.mtmt.hu/api/publication/34229256}, author = {Esfahani, M.J. and Farboud, S. and Ngo, H.-V.V. and Schneider, J. and Weber, F.D. and Talamini, L.M. and Dresler, M.}, doi = {10.1016/j.neubiorev.2023.105379}, journal-iso = {NEUROSCI BIOBEHAV R}, journal = {NEUROSCIENCE AND BIOBEHAVIORAL REVIEWS}, volume = {153}, unique-id = {34229256}, issn = {0149-7634}, year = {2023}, eissn = {1873-7528} } @article{MTMT:34019088, title = {The role of superficial and deep layers in the generation of high frequency oscillations and interictal epileptiform discharges in the human cortex}, url = {https://m2.mtmt.hu/api/publication/34019088}, author = {Fabó, Dániel and Bokodi, Virág and Szabó, Johanna Petra and Tóth, Emília and Salami, Pariya and Keller, Corey J and Hajnal, Boglárka Zsófia and Thesen, Thomas and Devinsky, Orrin and Doyle, Werner and Mehta, Ashesh and Madsen, Joseph and Eskandar, Emad and Erőss, Loránd and Ulbert, István and Halgren, Eric and Cash, Sydney S}, doi = {10.1038/s41598-022-22497-2}, journal-iso = {SCI REP}, journal = {SCIENTIFIC REPORTS}, volume = {13}, unique-id = {34019088}, issn = {2045-2322}, abstract = {Describing intracortical laminar organization of interictal epileptiform discharges (IED) and high frequency oscillations (HFOs), also known as ripples. Defining the frequency limits of slow and fast ripples. We recorded potential gradients with laminar multielectrode arrays (LME) for current source density (CSD) and multi-unit activity (MUA) analysis of interictal epileptiform discharges IEDs and HFOs in the neocortex and mesial temporal lobe of focal epilepsy patients. IEDs were observed in 20/29, while ripples only in 9/29 patients. Ripples were all detected within the seizure onset zone (SOZ). Compared to hippocampal HFOs, neocortical ripples proved to be longer, lower in frequency and amplitude, and presented non-uniform cycles. A subset of ripples (≈ 50%) co-occurred with IEDs, while IEDs were shown to contain variable high-frequency activity, even below HFO detection threshold. The limit between slow and fast ripples was defined at 150 Hz, while IEDs' high frequency components form clusters separated at 185 Hz. CSD analysis of IEDs and ripples revealed an alternating sink-source pair in the supragranular cortical layers, although fast ripple CSD appeared lower and engaged a wider cortical domain than slow ripples MUA analysis suggested a possible role of infragranularly located neural populations in ripple and IED generation. Laminar distribution of peak frequencies derived from HFOs and IEDs, respectively, showed that supragranular layers were dominated by slower (< 150 Hz) components. Our findings suggest that cortical slow ripples are generated primarily in upper layers while fast ripples and associated MUA in deeper layers. The dissociation of macro- and microdomains suggests that microelectrode recordings may be more selective for SOZ-linked ripples. We found a complex interplay between neural activity in the neocortical laminae during ripple and IED formation. We observed a potential leading role of cortical neurons in deeper layers, suggesting a refined utilization of LMEs in SOZ localization.}, year = {2023}, eissn = {2045-2322}, orcid-numbers = {Fabó, Dániel/0000-0001-5141-5351; Szabó, Johanna Petra/0000-0001-7690-9171; Erőss, Loránd/0000-0002-5796-5546; Ulbert, István/0000-0001-9941-9159} } @article{MTMT:34244111, title = {Sleep disrupts complex spiking dynamics in the neocortex and hippocampus}, url = {https://m2.mtmt.hu/api/publication/34244111}, author = {Gonzalez, Joaquin and Cavelli, Matias and Tort, Adriano B. L. and Torterolo, Pablo and Rubido, Nicolas}, doi = {10.1371/journal.pone.0290146}, journal-iso = {PLOS ONE}, journal = {PLOS ONE}, volume = {18}, unique-id = {34244111}, issn = {1932-6203}, abstract = {Neuronal interactions give rise to complex dynamics in cortical networks, often described in terms of the diversity of activity patterns observed in a neural signal. Interestingly, the complexity of spontaneous electroencephalographic signals decreases during slow-wave sleep (SWS); however, the underlying neural mechanisms remain elusive. Here, we analyse in-vivo recordings from neocortical and hippocampal neuronal populations in rats and show that the complexity decrease is due to the emergence of synchronous neuronal DOWN states. Namely, we find that DOWN states during SWS force the population activity to be more recurrent, deterministic, and less random than during REM sleep or wakefulness, which, in turn, leads to less complex field recordings. Importantly, when we exclude DOWN states from the analysis, the recordings during wakefulness and sleep become indistinguishable: the spiking activity in all the states collapses to a common scaling. We complement these results by implementing a critical branching model of the cortex, which shows that inducing DOWN states to only a percentage of neurons is enough to generate a decrease in complexity that replicates SWS.}, year = {2023}, eissn = {1932-6203}, orcid-numbers = {Gonzalez, Joaquin/0000-0002-8721-4292} } @article{MTMT:34244110, title = {The role of the sleep K-complex on the conversion from mild cognitive impairment to Alzheimer's disease}, url = {https://m2.mtmt.hu/api/publication/34244110}, author = {Gorgoni, Maurizio and Cenani, Jessica and Scarpelli, Serena and D'Atri, Aurora and Alfonsi, Valentina and Annarumma, Ludovica and Pietrogiacomi, Francesco and Ferrara, Michele and Marra, Camillo and Rossini, Paolo Maria and De Gennaro, Luigi}, doi = {10.1111/jsr.14046}, journal-iso = {J SLEEP RES}, journal = {JOURNAL OF SLEEP RESEARCH}, unique-id = {34244110}, issn = {0962-1105}, abstract = {The present literature points to an alteration of the human K-complex during non-rapid eye movement sleep in Alzheimer's disease. Nevertheless, the few findings on the K-complex changes in mild cognitive impairment and their possible predictive role on the Alzheimer's disease conversion show mixed findings, lack of replication, and a main interest for the frontal region. The aim of the present study was to assess K-complex measures in amnesic mild cognitive impairment subsequently converted in Alzheimer's disease over different cortical regions, comparing them with healthy controls and stable amnesic mild cognitive impairment. We assessed baseline K-complex density, amplitude, area under the curve and overnight changes in frontal, central and parietal midline derivations of 12 amnesic mild cognitive impairment subsequently converted in Alzheimer's disease, 12 stable amnesic mild cognitive impairment and 12 healthy controls. We also assessed delta electroencephalogram power, to determine if K-complex alterations in amnesic mild cognitive impairment occur with modification of the electroencephalogram power in the frequency range of the slow-wave activity. We found a reduced parietal K-complex density in amnesic mild cognitive impairment subsequently converted in Alzheimer's disease compared with stable amnesic mild cognitive impairment and healthy controls, without changes in K-complex morphology and overnight modulation. Both amnesic mild cognitive impairment groups showed decreased slow-wave sleep percentage compared with healthy controls. No differences between groups were observed in slow-wave activity power. Our findings suggest that K-complex alterations in mild cognitive impairment may be observed earlier in parietal regions, likely mirroring the topographical progression of Alzheimer's disease-related brain pathology, and express a frontal predominance only in a full-blown phase of Alzheimer's disease. Consistently with previous results, such K-complex modification occurs in the absence of significant electroencephalogram power changes in the slow oscillations range.}, keywords = {K-complex; Electroencephalogram; Alzheimer's disease; MILD COGNITIVE IMPAIRMENT; non-rapid eye movement sleep; SLOW-WAVE ACTIVITY}, year = {2023}, eissn = {1365-2869}, orcid-numbers = {Gorgoni, Maurizio/0000-0002-5544-5483; Scarpelli, Serena/0000-0002-9260-7111; Alfonsi, Valentina/0000-0002-9929-0399; Ferrara, Michele/0000-0003-2304-7576} } @article{MTMT:33850346, title = {Multielectrode Cortical Stimulation Selectively Induces Unidirectional Wave Propagation of Excitatory Neuronal Activity in Biophysical Neural Model}, url = {https://m2.mtmt.hu/api/publication/33850346}, author = {Halgren, Alma S. and Siegel, Zarek and Golden, Ryan and Bazhenov, Maxim}, doi = {10.1523/JNEUROSCI.1784-21.2023}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {43}, unique-id = {33850346}, issn = {0270-6474}, abstract = {Cortical stimulation is emerging as an experimental tool in basic research and a promising therapy for a range of neuro-psychiatric conditions. As multielectrode arrays enter clinical practice, the possibility of using spatiotemporal patterns of elec-trical stimulation to induce desired physiological patterns has become theoretically possible, but in practice can only be implemented by trial-and-error because of a lack of predictive models. Experimental evidence increasingly establishes travel-ing waves as fundamental to cortical information-processing, but we lack an understanding of how to control wave properties despite rapidly improving technologies. This study uses a hybrid biophysical-anatomical and neural-computational model to predict and understand how a simple pattern of cortical surface stimulation could induce directional traveling waves via asymmetric activation of inhibitory interneurons. We found that pyramidal cells and basket cells are highly activated by the anodal electrode and minimally activated by the cathodal electrodes, while Martinotti cells are moderately activated by both electrodes but exhibit a slight preference for cathodal stimulation. Network model simulations found that this asymmetrical activation results in a traveling wave in superficial excitatory cells that propagates unidirectionally away from the electrode array. Our study reveals how asymmetric electrical stimulation can easily facilitate traveling waves by relying on two distinct types of inhibitory interneuron activity to shape and sustain the spatiotemporal dynamics of endogenous local circuit mechanisms.}, keywords = {STIMULATION; MULTIELECTRODE ARRAYS; network model; biophysical model; cortical simulation}, year = {2023}, eissn = {1529-2401}, pages = {2482-2496} } @article{MTMT:34244114, title = {Diversity of electroencephalographic patterns during propofol-induced burst suppression}, url = {https://m2.mtmt.hu/api/publication/34244114}, author = {Jones, Keith G. G. and Lybbert, Carter and Euler, Matthew J. and Huang, Jason S. and Lunt, Seth and Richards, Sindhu V. V. and Jessop, Jacob E. E. and Larson, Adam and Odell, David H. H. and Kuck, Kai and Tadler, Scott C. C. and Mickey, Brian J. J.}, doi = {10.3389/fnsys.2023.1172856}, journal-iso = {FRONT SYST NEUROSCI}, journal = {FRONTIERS IN SYSTEMS NEUROSCIENCE}, volume = {17}, unique-id = {34244114}, abstract = {Burst suppression is a brain state consisting of high-amplitude electrical activity alternating with periods of quieter suppression that can be brought about by disease or by certain anesthetics. Although burst suppression has been studied for decades, few studies have investigated the diverse manifestations of this state within and between human subjects. As part of a clinical trial examining the antidepressant effects of propofol, we gathered burst suppression electroencephalographic (EEG) data from 114 propofol infusions across 21 human subjects with treatment-resistant depression. This data was examined with the objective of describing and quantifying electrical signal diversity. We observed three types of EEG burst activity: canonical broadband bursts (as frequently described in the literature), spindles (narrow-band oscillations reminiscent of sleep spindles), and a new feature that we call low-frequency bursts (LFBs), which are brief deflections of mainly sub-3-Hz power. These three features were distinct in both the time and frequency domains and their occurrence differed significantly across subjects, with some subjects showing many LFBs or spindles and others showing very few. Spectral-power makeup of each feature was also significantly different across subjects. In a subset of nine participants with high-density EEG recordings, we noted that each feature had a unique spatial pattern of amplitude and polarity when measured across the scalp. Finally, we observed that the Bispectral Index Monitor, a commonly used clinical EEG monitor, does not account for the diversity of EEG features when processing the burst suppression state. Overall, this study describes and quantifies variation in the burst suppression EEG state across subjects and repeated infusions of propofol. These findings have implications for the understanding of brain activity under anesthesia and for individualized dosing of anesthetic drugs.}, keywords = {DEPRESSION; anesthesia; propofol; electroencephalograph (EEG); Burst suppression}, year = {2023}, eissn = {1662-5137} } @inproceedings{MTMT:33850347, title = {Fast Fourier Transform Coupled with Machine Learning Algorithm for K-Complexes Detection}, url = {https://m2.mtmt.hu/api/publication/33850347}, author = {Morad, Mohammed and Oudah, Atheer Y. and Diykh, Mohammed and Marhoon, Haydar Abdulameer and Taher, Hazeem B.}, booktitle = {Proceedings of Third Doctoral Symposium on Computational Intelligence}, doi = {10.1007/978-981-19-3148-2_26}, unique-id = {33850347}, abstract = {This paper proposes a novel K-complexes (KCs) detection approach using sleep electroencephalogram (EEG) recordings. A segmentation technique is used to partition an EEG signal into intervals. Then, fast Fourier transform (FFT) is applied to each EEG segment. To find out the most effective input features to represent the EEG signal, the FFT coefficients were investigated. The extracted features are then utilized as the input to an ensemble classifier which is designed using three classifiers: K-means, the Naive Bayes algorithm and least square support vector machines (LS-SVM). A comparison with existing studies is made and the results showed that the proposed model outperformed state of the art. The proposed approach can be developed as an online system to detect KCs in EEG signals. In addition, it can be applied to other EEG data such as detect sleep apnoea.}, keywords = {Electroencephalogram; Ensemble classifier; Fast Fourier transform; K-complexes}, year = {2023}, pages = {307-313}, orcid-numbers = {Marhoon, Haydar Abdulameer/0000-0002-2711-1857} } @article{MTMT:33769802, title = {Proteostasis failure exacerbates neuronal circuit dysfunction and sleep impairments in Alzheimer’s disease}, url = {https://m2.mtmt.hu/api/publication/33769802}, author = {Morrone, Christopher Daniel and Raghuraman, Radha and Hussaini, S. Abid and Yu, Wai Haung}, doi = {10.1186/s13024-023-00617-4}, journal-iso = {MOL NEURODEGENER}, journal = {MOLECULAR NEURODEGENERATION}, volume = {18}, unique-id = {33769802}, issn = {1750-1326}, abstract = {Failed proteostasis is a well-documented feature of Alzheimer’s disease, particularly, reduced protein degradation and clearance. However, the contribution of failed proteostasis to neuronal circuit dysfunction is an emerging concept in neurodegenerative research and will prove critical in understanding cognitive decline. Our objective is to convey Alzheimer’s disease progression with the growing evidence for a bidirectional relationship of sleep disruption and proteostasis failure. Proteostasis dysfunction and tauopathy in Alzheimer’s disease disrupts neurons that regulate the sleep–wake cycle, which presents behavior as impaired slow wave and rapid eye movement sleep patterns. Subsequent sleep loss further impairs protein clearance. Sleep loss is a defined feature seen early in many neurodegenerative disorders and contributes to memory impairments in Alzheimer’s disease. Canonical pathological hallmarks, β-amyloid, and tau, directly disrupt sleep, and neurodegeneration of locus coeruleus, hippocampal and hypothalamic neurons from tau proteinopathy causes disruption of the neuronal circuitry of sleep. Acting in a positive-feedback-loop, sleep loss and circadian rhythm disruption then increase spread of β-amyloid and tau, through impairments of proteasome, autophagy, unfolded protein response and glymphatic clearance. This phenomenon extends beyond β-amyloid and tau, with interactions of sleep impairment with the homeostasis of TDP-43, α-synuclein, FUS, and huntingtin proteins, implicating sleep loss as an important consideration in an array of neurodegenerative diseases and in cases of mixed neuropathology. Critically, the dynamics of this interaction in the neurodegenerative environment are not fully elucidated and are deserving of further discussion and research. Finally, we propose sleep-enhancing therapeutics as potential interventions for promoting healthy proteostasis, including β-amyloid and tau clearance, mechanistically linking these processes. With further clinical and preclinical research, we propose this dynamic interaction as a diagnostic and therapeutic framework, informing precise single- and combinatorial-treatments for Alzheimer’s disease and other brain disorders.}, year = {2023}, eissn = {1750-1326}, orcid-numbers = {Morrone, Christopher Daniel/0000-0002-5887-2691} } @article{MTMT:33155347, title = {Lateralized tactile stimulation during NREM sleep globally increases both slow and fast frequency activities}, url = {https://m2.mtmt.hu/api/publication/33155347}, author = {Simor, Péter Dániel and Bogdány, Tamás and Sifuentes-Ortega, R. and Rovai, A. and Peigneux, P.}, doi = {10.1111/psyp.14191}, journal-iso = {PSYCHOPHYSIOLOGY}, journal = {PSYCHOPHYSIOLOGY}, volume = {60}, unique-id = {33155347}, issn = {0048-5772}, year = {2023}, eissn = {1469-8986}, orcid-numbers = {Simor, Péter Dániel/0000-0003-0695-166X; Bogdány, Tamás/0000-0001-5563-5597} } @article{MTMT:34244113, title = {How coupled slow oscillations, spindles and ripples coordinate neuronal processing and communication during human sleep}, url = {https://m2.mtmt.hu/api/publication/34244113}, author = {Staresina, Bernhard P. and Niediek, Johannes and Borger, Valeri and Surges, Rainer and Mormann, Florian}, doi = {10.1038/s41593-023-01381-w}, journal-iso = {NAT NEUROSCI}, journal = {NATURE NEUROSCIENCE}, volume = {26}, unique-id = {34244113}, issn = {1097-6256}, abstract = {Using direct recordings from human MTL neurons during sleep, Staresina et al. reveal that neuronal firing and communication-thought to underlie synaptic plasticity and learning-are controlled by coupled slow oscillations, spindles and ripples.Learning and plasticity rely on fine-tuned regulation of neuronal circuits during offline periods. An unresolved puzzle is how the sleeping brain, in the absence of external stimulation or conscious effort, coordinates neuronal firing rates (FRs) and communication within and across circuits to support synaptic and systems consolidation. Using intracranial electroencephalography combined with multiunit activity recordings from the human hippocampus and surrounding medial temporal lobe (MTL) areas, we show that, governed by slow oscillation (SO) up-states, sleep spindles set a timeframe for ripples to occur. This sequential coupling leads to a stepwise increase in (1) neuronal FRs, (2) short-latency cross-correlations among local neuronal assemblies and (3) cross-regional MTL interactions. Triggered by SOs and spindles, ripples thus establish optimal conditions for spike-timing-dependent plasticity and systems consolidation. These results unveil how the sequential coupling of specific sleep rhythms orchestrates neuronal processing and communication during human sleep.}, year = {2023}, eissn = {1546-1726}, pages = {1429-+}, orcid-numbers = {Niediek, Johannes/0000-0003-3323-2986; Mormann, Florian/0000-0003-1305-8028} } @article{MTMT:34225764, title = {Electrochemical and electrophysiological considerations for clinical high channel count neural interfaces}, url = {https://m2.mtmt.hu/api/publication/34225764}, author = {Vatsyayan, R. and Lee, J. and Bourhis, A.M. and Tchoe, Y. and Cleary, D.R. and Tonsfeldt, K.J. and Lee, K. and Montgomery-Walsh, R. and Paulk, A.C. and Hoi, Sang U. and Cash, S.S. and Dayeh, S.A.}, doi = {10.1557/s43577-023-00537-0}, journal-iso = {MRS BULL}, journal = {MRS BULLETIN}, volume = {48}, unique-id = {34225764}, issn = {0883-7694}, year = {2023}, eissn = {1938-1425}, pages = {531-546} } @article{MTMT:32943967, title = {The Brain Selectively Tunes to Unfamiliar Voices during Sleep}, url = {https://m2.mtmt.hu/api/publication/32943967}, author = {Ameen, Mohamed S. and Heib, Dominik P. J. and Blume, Christine and Schabus, Manuel}, doi = {10.1523/JNEUROSCI.2524-20.2021}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {42}, unique-id = {32943967}, issn = {0270-6474}, abstract = {The brain continues to respond selectively to environmental stimuli during sleep. However, the functional role of such responses, and whether they reflect information processing or rather sensory inhibition, is not fully understood. Here, we present 17 human sleepers (14 females) with their own name and two unfamiliar first names, spoken by either a familiar voice (FV) or an unfamiliar voice (UFV), while recording polysomnography during a full night of sleep. We detect K-complexes, sleep spindles, and microarousals, and assess event-related and frequency responses as well as intertrial phase synchronization to the different stimuli presented during nonrapid eye movement (NREM) sleep. We show that UFVs evoke more K-complexes and microarousals than FVs. When both stimuli evoke a K-complex, we observe larger evoked potentials, more precise time-locking of brain responses in the delta band (1-4 Hz), and stronger activity in the high frequency (>16 Hz) range, in response to UFVs relative to FVs. Crucially, these differences in brain responses disappear completely when no K-complexes are evoked by the auditory stimuli. Our findings highlight discrepancies in brain responses to auditory stimuli based on their relevance to the sleeper and propose a key role for K-complexes in the modulation of sensory processing during sleep. We argue that such content-specific, dynamic reactivity to external sensory information enables the brain to enter a sentinel processing mode in which it engages in the important internal processes that are ongoing during sleep while still maintaining the ability to process vital external sensory information.}, keywords = {information processing; EEG; auditory stimulation; sleep; K-complexes; microarousals}, year = {2022}, eissn = {1529-2401}, pages = {1791-1803}, orcid-numbers = {Ameen, Mohamed S./0000-0003-4147-490X; Blume, Christine/0000-0003-2328-9612; Schabus, Manuel/0000-0001-5899-8772} } @article{MTMT:32945136, title = {Abnormal timing of slow wave synchronization processes in non-rapid eye movement sleep parasomnias}, url = {https://m2.mtmt.hu/api/publication/32945136}, author = {Cataldi, Jacinthe and Stephan, Aurelie M. and Marchi, Nicola A. and Haba-Rubio, Jose and Siclari, Francesca}, doi = {10.1093/sleep/zsac111}, journal-iso = {SLEEP}, journal = {SLEEP}, unique-id = {32945136}, issn = {0161-8105}, abstract = {Study Objectives Sleepwalking, confusional arousals, and sleep terrors are parasomnias occurring out of non-rapid eye movement (NREM) sleep. Several previous studies have described EEG changes associated with NREM parasomnia episodes, but it remains unclear whether these changes are specific to parasomnia episodes or whether they are part of the normal awakening process. Here we directly compared regional brain activity, measured with high-density (hd-) EEG, between parasomnia episodes and normal awakenings (without behavioral manifestations of parasomnia). Methods Twenty adult patients with non-rapid eye movement parasomnias underwent a baseline hd-EEG recording (256 electrodes) followed by a recovery sleep recording after 25 h of total sleep deprivation, during which auditory stimuli were administered to provoke parasomnia episodes. Results Both normal awakenings (n = 25) and parasomnia episodes (n = 96) were preceded by large, steep, and "K-complex-like" slow waves in frontal and central brain regions, and by a concomitant increase in high-frequency EEG (beta) activity. Compared to normal awakenings, parasomnia episodes occurred on a less activated EEG background and displayed higher slow wave activity (SWA) and lower beta activity in frontal and central brain regions after movement onset. Conclusions Our results suggest that non-rapid eye movement awakenings, irrespective of behavioral manifestations of parasomnia episodes, involve an arousal-related slow wave synchronization process that predominantly recruits frontal and central brain areas. In parasomnia episodes, this synchronization process comes into play abnormally during periods of high SWA and is associated with higher SWA after movement onset. Thus, an abnormal timing of arousal-related slow wave synchronization processes could underlie the occurrence of NREM parasomnias.}, keywords = {EEG; Sleepwalking; parasomnia; Source modeling; awakening; awakening; Disorders of arousal}, year = {2022}, eissn = {1550-9109}, orcid-numbers = {Siclari, Francesca/0000-0003-2061-9719} } @article{MTMT:32945137, title = {Spindle-targeted acoustic stimulation may stabilize an ongoing nap}, url = {https://m2.mtmt.hu/api/publication/32945137}, author = {Choi, Jinyoung and Jun, Sung Chan}, doi = {10.1111/jsr.13583}, journal-iso = {J SLEEP RES}, journal = {JOURNAL OF SLEEP RESEARCH}, unique-id = {32945137}, issn = {0962-1105}, abstract = {There have been numerous attempts over the decades to introduce closed-loop feedback to induce sleep oscillations. Recently, our group also introduced closed-loop acoustic feedback to the sleep spindle and reported improved procedural memory consolidation during a nap with spindle-targeted pink noise stimulation. In this study, we replicated our previous work with a control condition in an attempt to investigate the effect of closed-loop feedback on procedural memory. The results demonstrated a significant improvement in the subjects' procedural learning and reduced wake time during the nap with closed-loop acoustic stimulation compared with the control condition. Further, we found that randomized acoustic stimuli lead to more frequent spindle activity and a faster decrement in slow oscillation power compared with the sham condition. There were strong correlations between slow oscillation and measures related to sleep efficiency as well. Interestingly, we found a marginal enhancement in procedural learning during the nap with the closed-loop acoustic stimulation compared with the sham nap. We also found a marginal decrement in theta power during the nap with closed-loop feedback compared with the sham nap, and a negative correlation between slow oscillation and theta power. We speculate that the marginal improvement in procedural learning may be related to closed-loop acoustic feedback's stabilization of non-rapid eye movement sleep. Taken together, this study shows that the closed-loop feedback method has the potential to stabilize sleep and improve procedural memory.}, keywords = {sleep spindle; Slow oscillation; automated spindle detection; Procedural memory consolidation; closed-loop acoustic feedback}, year = {2022}, eissn = {1365-2869}, orcid-numbers = {Choi, Jinyoung/0000-0003-1571-6274} } @article{MTMT:33850348, title = {The Intention to React to Sounds Induces Sleep Disturbances and Alters Brain Responses to Sounds during Sleep: A Pilot Study}, url = {https://m2.mtmt.hu/api/publication/33850348}, author = {Combertaldi, Selina Ladina and Wick, Anna Zoe and Rasch, Bjorn}, doi = {10.3390/clockssleep4040044}, journal-iso = {CLOCKS & SLEEP}, journal = {CLOCKS & SLEEP}, volume = {4}, unique-id = {33850348}, abstract = {Background: Pre-sleep intentions to react to stimuli during sleep affect sleep processes in spite of reductions in conscious awareness. Here, we compare influences of sounds presented during sleep (with and without intentions to react) with the effect of pre-sleep intentions on sleep (with and without sounds being present during sleep). Methods: Twenty-six young, healthy participants spent two experimental nights in the sleep laboratory. On one night, they were instructed to react to sounds during sleep ("on call"); on the other night, not ("neutral"). Unknown to the subjects, sounds were presented at a low volume in both nights in one group. No sound was presented in any of the two nights in the other group. Results: The instruction of being "on call" decreased objective sleep efficiency independently of sounds being present or not. In addition, event-related responses to sounds as well as slow-wave activity were reduced when being "on call". Conclusions: Pre-sleep intentions to react impair sleep independently of sounds actually being present and influence brain responses to sounds during sleep. Our results highlight the importance of subjective relevance for reducing negative impact of external noise sources such as traffic or church bells.}, keywords = {sleep; REPLICATION; ERP; Alarms; instructions; on call}, year = {2022}, eissn = {2624-5175}, pages = {561-576}, orcid-numbers = {Combertaldi, Selina Ladina/0000-0003-1697-8997; Rasch, Bjorn/0000-0001-7607-3415} } @article{MTMT:32945135, title = {Human Spindle Variability}, url = {https://m2.mtmt.hu/api/publication/32945135}, author = {Gonzalez, Christopher and Jiang, Xi and Gonzalez-Martinez, Jorge and Halgren, Eric}, doi = {10.1523/JNEUROSCI.1786-21.2022}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {42}, unique-id = {32945135}, issn = {0270-6474}, abstract = {In humans, sleep spindles are 10- to 16-Hz oscillations lasting approximately 05-2 s. Spindles, along with cortical slow oscillations, may facilitate memory consolidation by enabling synaptic plasticity. Early recordings of spindles at the scalp found anterior channels had overall slower frequency than central-posterior channels. This robust, topographical finding led to dichotomizing spindles as "slow" versus "fast," modeled as two distinct spindle generators in frontal versus posterior cortex. Using a large dataset of intracranial stereoelectroencephalographic (sEEG) recordings from 20 patients (13 female, 7 male) and 365 bipolar recordings, we show that the difference in spindle frequency between frontal and parietal channels is comparable to the variability in spindle frequency within the course of individual spindles, across different spindles recorded by a given site, and across sites within a given region. Thus, fast and slow spindles only capture average differences that obscure a much larger underlying overlap in frequency. Furthermore, differences in mean frequency are only one of several ways that spindles differ. For example, compared with parietal, frontal spindles are smaller, tend to occur after parietal when both are engaged, and show a larger decrease in frequency within-spindles. However, frontal and parietal spindles are similar in being longer, less variable, and more widespread than occipital, temporal, and Rolandic spindles. These characteristics are accentuated in spindles which are highly phase-locked to posterior hippocampal spindles. We propose that rather than a strict parietal-fast/frontal-slow dichotomy, spindles differ continuously and quasi-independently in multiple dimensions, with variability due about equally to within-spindle, within-region, and between-region factors.}, keywords = {CORTEX; hippocampus; Slow oscillation; sleep; SPINDLE; Intracranial}, year = {2022}, eissn = {1529-2401}, pages = {4517-4537} } @article{MTMT:33850350, title = {Non-REM sleep electrophysiology in REM sleep behaviour disorder: A narrative mini-review}, url = {https://m2.mtmt.hu/api/publication/33850350}, author = {Gorgoni, Maurizio and Galbiati, Andrea}, doi = {10.1016/j.neubiorev.2022.104909}, journal-iso = {NEUROSCI BIOBEHAV R}, journal = {NEUROSCIENCE AND BIOBEHAVIORAL REVIEWS}, volume = {142}, unique-id = {33850350}, issn = {0149-7634}, abstract = {Isolated Rapid Eye Movement Sleep (REM) behaviour disorder (iRBD) is a prodromal sign of neurodegenerative disorders. Empirical findings point to a role of non-REM (NREM) sleep alterations in neurodegenerative pro-cesses. Therefore, the interest in NREM sleep electroencephalography (EEG) of iRBD is progressively increasing. The present review aims to provide an updated state of the art on NREM sleep electrophysiology in iRBD. First, we describe findings on NREM EEG power spectra. Then, we consider specific NREM sleep EEG hallmarks (i.e., slow waves, slow oscillations, K-complexes, sleep spindles). Finally, we focus on NREM sleep instability. The reviewed literature is small and heterogeneous, but rapidly growing. The most consistent findings point to alteration of sleep spindles and cyclic alternating pattern in RBD. A larger discrepancy characterized results on slow wave activity, but recent studies using a topographical approach provide promising results. Evidence on the relationship of NREM sleep alterations with neurodegenerative processes in iRBD, as well as longitudinal changes, are scarce. We discuss the main methodological limitations, highlighting possible future directions.}, keywords = {EEG; NREM sleep; Sleep spindles; CYCLIC ALTERNATING PATTERN; slow oscillations; Slow waves; REM sleep behaviour disorder; K-complexes}, year = {2022}, eissn = {1873-7528}, orcid-numbers = {Gorgoni, Maurizio/0000-0002-5544-5483; Galbiati, Andrea/0000-0001-8132-1399} } @article{MTMT:32785453, title = {Bursting of excitatory cells is linked to interictal epileptic discharge generation in humans.}, url = {https://m2.mtmt.hu/api/publication/32785453}, author = {Hofer, Katharina and Kandrács, Ágnes and Tóth, Kinga and Hajnal, Boglárka Zsófia and Bokodi, Virág and Tóth, Estilla Zsófia and Erőss, Loránd and Entz, László and Bagó, Attila György and Fabó, Dániel and Ulbert, István and Wittner, Lucia}, doi = {10.1038/s41598-022-10319-4}, journal-iso = {SCI REP}, journal = {SCIENTIFIC REPORTS}, volume = {12}, unique-id = {32785453}, issn = {2045-2322}, abstract = {Knowledge about the activity of single neurons is essential in understanding the mechanisms of synchrony generation, and particularly interesting if related to pathological conditions. The generation of interictal spikes-the hypersynchronous events between seizures-is linked to hyperexcitability and to bursting behaviour of neurons in animal models. To explore its cellular mechanisms in humans we investigated the activity of clustered single neurons in a human in vitro model generating both physiological and epileptiform synchronous events. We show that non-epileptic synchronous events resulted from the finely balanced firing of excitatory and inhibitory cells, which was shifted towards an enhanced excitability in epileptic tissue. In contrast, interictal-like spikes were characterised by an asymmetric overall neuronal discharge initiated by excitatory neurons with the presumptive leading role of bursting pyramidal cells, and possibly terminated by inhibitory interneurons. We found that the overall burstiness of human neocortical neurons is not necessarily related to epilepsy, but the bursting behaviour of excitatory cells comprising both intrinsic and synaptically driven bursting is clearly linked to the generation of epileptiform synchrony.}, year = {2022}, eissn = {2045-2322}, orcid-numbers = {Kandrács, Ágnes/0000-0002-6408-2397; Tóth, Kinga/0000-0002-8751-8499; Erőss, Loránd/0000-0002-5796-5546; Fabó, Dániel/0000-0001-5141-5351; Ulbert, István/0000-0001-9941-9159; Wittner, Lucia/0000-0001-6800-0953} } @article{MTMT:33350248, title = {Individual slow wave events give rise to macroscopic fMRI signatures and drive the strength of the BOLD signal in human resting-state EEG-fMRI recordings}, url = {https://m2.mtmt.hu/api/publication/33350248}, author = {Ilhan-Bayrakci, Merve and Cabral-Calderin, Yuranny and Bergmann, Til Ole and Tuscher, Oliver and Stroh, Albrecht}, doi = {10.1093/cercor/bhab516}, journal-iso = {CEREB CORTEX}, journal = {CEREBRAL CORTEX}, volume = {32}, unique-id = {33350248}, issn = {1047-3211}, abstract = {The slow wave state is a general state of quiescence interrupted by sudden bursts of activity or so-called slow wave events (SWEs). Recently, the relationship between SWEs and blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) signals was assessed in rodent models which revealed cortex-wide BOLD activation. However, it remains unclear which macroscopic signature corresponds to these specific neurophysiological events in the human brain. Therefore, we analyzed simultaneous electroencephalographic (EEG)-fMRI data during human non-REM sleep. SWEs individually detected in the EEG data were used as predictors in event-related fMRI analyses to examine the relationship between SWEs and fMRI signals. For all 10 subjects we identified significant changes in BOLD activity associated with SWEs covering substantial parts of the gray matter. As demonstrated in rodents, we observed a direct relation of a neurophysiological event to specific BOLD activation patterns. We found a correlation between the number of SWEs and the spatial extent of these BOLD activation patterns and discovered that the amplitude of the BOLD response strongly depends on the SWE amplitude. As altered SWE propagation has recently been found in neuropsychiatric diseases, it is critical to reveal the brain's physiological slow wave state networks to potentially establish early imaging biomarkers for various diseases long before disease onset.}, keywords = {slow oscillations; brain states; EEG-fMRI; thalamocortical networks; slow wave events}, year = {2022}, eissn = {1460-2199}, pages = {4782-4796}, orcid-numbers = {Ilhan-Bayrakci, Merve/0000-0001-7574-5304} } @article{MTMT:33157862, title = {Rhythmicity in heart rate and its surges usher a special period of sleep, a likely home for PGO waves}, url = {https://m2.mtmt.hu/api/publication/33157862}, author = {Ioannides, A.A. and Orphanides, G.A. and Liu, L.}, doi = {10.1016/j.crphys.2022.02.003}, journal-iso = {CURR RES PHYSIOL}, journal = {CURRENT RESEARCH IN PHYSIOLOGY}, volume = {5}, unique-id = {33157862}, issn = {2665-9441}, year = {2022}, pages = {118-141} } @article{MTMT:33850349, title = {Instability of non-REM sleep in older women evaluated by sleep-stage transition and envelope analyses}, url = {https://m2.mtmt.hu/api/publication/33850349}, author = {Park, Insung and Kokudo, Chihiro and Seol, Jaehoon and Ishihara, Asuka and Zhang, Simeng and Uchizawa, Akiko and Osumi, Haruka and Miyamoto, Ryusuke and Horie, Kazumasa and Suzuki, Chihiro and Suzuki, Yoko and Okura, Tomohiro and Diaz, Javier and Vogt, Kaspar E. E. and Tokuyama, Kumpei}, doi = {10.3389/fnagi.2022.1050648}, journal-iso = {FRONT AGING NEUROSCI}, journal = {FRONTIERS IN AGING NEUROSCIENCE}, volume = {14}, unique-id = {33850349}, issn = {1663-4365}, abstract = {Study objectiveTraditionally, age-related deterioration of sleep architecture in older individuals has been evaluated by visual scoring of polysomnographic (PSG) recordings with regard to total sleep time and latencies. In the present study, we additionally compared the non-REM sleep (NREM) stage and delta, theta, alpha, and sigma wave stability between young and older subjects to extract features that may explain age-related changes in sleep. MethodsPolysomnographic recordings were performed in 11 healthy older (72.6 +/- 2.4 years) and 9 healthy young (23.3 +/- 1.1 years) females. In addition to total sleep time, the sleep stage, delta power amplitude, and delta, theta, alpha, and sigma wave stability were evaluated by sleep stage transition analysis and a novel computational method based on a coefficient of variation of the envelope (CVE) analysis, respectively. ResultsIn older subjects, total sleep time and slow-wave sleep (SWS) time were shorter whereas wake after sleep onset was longer. The number of SWS episodes was similar between age groups, however, sleep stage transition analysis revealed that SWS was less stable in older individuals. NREM sleep stages in descending order of delta power were: SWS, N2, and N1, and delta power during NREM sleep in older subjects was lower than in young subjects. The CVE of the delta-band is an index of delta wave stability and showed significant differences between age groups. When separately analyzed for each NREM stage, different CVE clusters in NREM were clearly observed between young and older subjects. A lower delta CVE and amplitude were also observed in older subjects compared with young subjects in N2 and SWS. Additionally, lower CVE values in the theta, alpha and sigma bands were also characteristic of older participants. ConclusionThe present study shows a decrease of SWS stability in older subjects together with a decrease in delta wave amplitude. Interestingly, the decrease in SWS stability coincided with an increase in short-term delta, theta, sigma, and alpha power stability revealed by lower CVE. Loss of electroencephalograms (EEG) variability might be a useful marker of brain age.}, keywords = {OLDER; delta power; SWS; K-complexes; Envelope analysis; sleep transition}, year = {2022}, eissn = {1663-4365}, orcid-numbers = {Uchizawa, Akiko/0000-0003-0945-5733} } @article{MTMT:32637689, title = {Autonomic arousals contribute to brain fluid pulsations during sleep}, url = {https://m2.mtmt.hu/api/publication/32637689}, author = {Picchioni, D. and Özbay, P.S. and Mandelkow, H. and de, Zwart J.A. and Wang, Y. and van, Gelderen P. and Duyn, J.H.}, doi = {10.1016/j.neuroimage.2022.118888}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {249}, unique-id = {32637689}, issn = {1053-8119}, year = {2022}, eissn = {1095-9572} } @article{MTMT:33061538, title = {Role of anterior thalamic circuitry during sleep}, url = {https://m2.mtmt.hu/api/publication/33061538}, author = {Szabó, Johanna Petra and Fabó, Dániel and Pető, Nóra and Sákovics, Anna and Bódizs, Róbert}, doi = {10.1016/j.eplepsyres.2022.106999}, journal-iso = {EPILEPSY RES}, journal = {EPILEPSY RESEARCH}, volume = {186}, unique-id = {33061538}, issn = {0920-1211}, year = {2022}, eissn = {1872-6844}, orcid-numbers = {Szabó, Johanna Petra/0000-0001-7690-9171; Fabó, Dániel/0000-0001-5141-5351; Bódizs, Róbert/0000-0001-5341-060X} } @article{MTMT:33226625, title = {The sleep EEG envelope is a novel, neuronal firing-based human biomarker}, url = {https://m2.mtmt.hu/api/publication/33226625}, author = {Ujma, Przemyslaw Péter and Dresler, Martin and Simor, Péter Dániel and Fabó, Dániel and Ulbert, István and Erőss, Loránd and Bódizs, Róbert}, doi = {10.1038/s41598-022-22255-4}, journal-iso = {SCI REP}, journal = {SCIENTIFIC REPORTS}, volume = {12}, unique-id = {33226625}, issn = {2045-2322}, abstract = {Sleep EEG reflects voltage differences relative to a reference, while its spectrum reflects its composition of various frequencies. In contrast, the envelope of the sleep EEG reflects the instantaneous amplitude of oscillations, while its spectrum reflects the rhythmicity of the occurrence of these oscillations. The sleep EEG spectrum is known to relate to demographic, psychological and clinical characteristics, but the envelope spectrum has been rarely studied. In study 1, we demonstrate in human invasive data from cortex-penetrating microelectrodes and subdural grids that the sleep EEG envelope spectrum reflects neuronal firing. In study 2, we demonstrate that the scalp EEG envelope spectrum is stable within individuals. A multivariate learning algorithm could predict age (r = 0.6) and sex (r = 0.5) from the EEG envelope spectrum. With age, oscillations shifted from a 4–5 s rhythm to faster rhythms. Our results demonstrate that the sleep envelope spectrum is a promising biomarker of demographic and disease-related phenotypes.}, year = {2022}, eissn = {2045-2322}, orcid-numbers = {Ujma, Przemyslaw Péter/0000-0002-7981-3009; Simor, Péter Dániel/0000-0003-0695-166X; Fabó, Dániel/0000-0001-5141-5351; Ulbert, István/0000-0001-9941-9159; Erőss, Loránd/0000-0002-5796-5546; Bódizs, Róbert/0000-0001-5341-060X} } @article{MTMT:32491678, title = {High Gamma Activity in Cortex and Hippocampus is Correlated with Autonomic Tone During Sleep}, url = {https://m2.mtmt.hu/api/publication/32491678}, author = {Alasfour, Abdulwahab and Jiang, Xi and Gonzalez-Martinez, Jorge and Gilja, Vikash and Halgren, Eric}, doi = {10.1523/ENEURO.0194-21.2021}, journal-iso = {ENEURO}, journal = {ENEURO}, volume = {8}, unique-id = {32491678}, year = {2021}, eissn = {2373-2822}, orcid-numbers = {Halgren, Eric/0000-0001-5926-6872} } @article{MTMT:32114095, title = {Cortical and subcortical hemodynamic changes during sleep slow waves in human light sleep}, url = {https://m2.mtmt.hu/api/publication/32114095}, author = {Betta, M. and Handjaras, G. and Leo, A. and Federici, A. and Farinelli, V. and Ricciardi, E. and Siclari, F. and Meletti, S. and Ballotta, D. and Benuzzi, F. and Bernardi, G.}, doi = {10.1016/j.neuroimage.2021.118117}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {236}, unique-id = {32114095}, issn = {1053-8119}, year = {2021}, eissn = {1095-9572} } @article{MTMT:32494218, title = {Exploring the functional role and neural correlates of K-complexes in isolated rapid eye movement sleep behavior disorder}, url = {https://m2.mtmt.hu/api/publication/32494218}, author = {Galbiati, A. and Carli, G. and Fasiello, E. and Casoni, F. and Zucconi, M. and De, Gennaro L. and Perani, D. and Ferini-Strambi, L.}, doi = {10.1016/j.cortex.2021.08.012}, journal-iso = {CORTEX}, journal = {CORTEX: A JOURNAL DEVOTED TO THE STUDY OF THE NERVOUS SYSTEM AND BEHAVIOR}, volume = {145}, unique-id = {32494218}, issn = {0010-9452}, year = {2021}, eissn = {1973-8102}, pages = {105-114} } @article{MTMT:32114102, title = {Sex differences in blood pressure responsiveness to spontaneous K-complexes during stage II sleep}, url = {https://m2.mtmt.hu/api/publication/32114102}, author = {Greenlund, I.M. and Smoot, C.A. and Carter, J.R.}, doi = {10.1152/JAPPLPHYSIOL.00825.2020}, journal-iso = {J APPL PHYSIOL}, journal = {JOURNAL OF APPLIED PHYSIOLOGY}, volume = {130}, unique-id = {32114102}, issn = {8750-7587}, year = {2021}, eissn = {1522-1601}, pages = {491-497} } @article{MTMT:32277132, title = {Sounding It Out: Auditory Stimulation and Overnight Memory Processing}, url = {https://m2.mtmt.hu/api/publication/32277132}, author = {Harrington, Marcus O. and Cairney, Scott A.}, doi = {10.1007/s40675-021-00207-0}, journal-iso = {CURR SLEEP MED REP}, journal = {CURRENT SLEEP MEDICINE REPORTS}, volume = {7}, unique-id = {32277132}, issn = {2198-6401}, abstract = {Purpose of Review Auditory stimulation is a technique that can enhance neural oscillations linked to overnight memory consolidation. In this review, we evaluate the impacts of auditory stimulation on the neural oscillations of sleep and associated memory processes in a variety of populations. Recent Findings Cortical EEG recordings of slow-wave sleep (SWS) are characterised by two cardinal oscillations: slow oscillations (SOs) and sleep spindles. Auditory stimulation delivered in SWS enhances SOs and phase-coupled spindle activity in healthy children and adults, children with ADHD, adults with mild cognitive impairment and patients with major depression. Under certain conditions, auditory stimulation bolsters the benefits of SWS for memory consolidation, although further work is required to fully understand the factors affecting stimulation-related memory gains. Recent work has turned to rapid eye movement (REM) sleep, demonstrating that auditory stimulation can be used to manipulate REM sleep theta oscillations. Auditory stimulation enhances oscillations linked to overnight memory processing and shows promise as a technique for enhancing the memory benefits of sleep.}, keywords = {memory consolidation; Sleep spindles; SLOW-WAVE SLEEP; slow oscillations; rapid eye movement sleep; closed-loop stimulation}, year = {2021}, pages = {112-119} } @article{MTMT:32114099, title = {Cross-participant prediction of vigilance stages through the combined use of wPLI and wSMI EEG functional connectivity metrics}, url = {https://m2.mtmt.hu/api/publication/32114099}, author = {Imperatori, L.S. and Cataldi, J. and Betta, M. and Ricciardi, E. and Ince, R.A.A. and Siclari, F. and Bernardi, G.}, doi = {10.1093/sleep/zsaa247}, journal-iso = {SLEEP}, journal = {SLEEP}, volume = {44}, unique-id = {32114099}, issn = {0161-8105}, year = {2021}, eissn = {1550-9109} } @article{MTMT:31420456, title = {Current ideas about the roles of rapid eye movement and non-rapid eye movement sleep in brain development}, url = {https://m2.mtmt.hu/api/publication/31420456}, author = {Knoop, Marit S. and de Groot, Eline R. and Dudink, Jeroen}, doi = {10.1111/apa.15485}, journal-iso = {ACTA PAEDIATR}, journal = {ACTA PAEDIATRICA}, volume = {110}, unique-id = {31420456}, issn = {0803-5253}, abstract = {Understanding the links between sleep and brain development is important, as rapid eye movement (REM) sleep and non-REM (NREM) sleep seem to contribute to different aspects of brain maturation. If children have sleep problems, REM sleep and NREM sleep are likely to have different consequences for their developing brain, depending on their age. We highlight important discoveries from human and animal research on the role sleep plays in brain development. A hypothetical model is presented to explain the dynamic relationship of REM sleep and NREM sleep with different processes of brain maturation, with implications for current neonatal care and future research.}, keywords = {brain development; Rapid eye movement; neonatal care; child maturation; sleep ontogeny}, year = {2021}, eissn = {1651-2227}, pages = {36-44}, orcid-numbers = {Dudink, Jeroen/0000-0003-0446-3646} } @article{MTMT:32494219, title = {K-complexes are a sensitive marker of noise-related sensory processing during sleep: A pilot study}, url = {https://m2.mtmt.hu/api/publication/32494219}, author = {Lechat, B. and Hansen, K. and Micic, G. and Decup, F. and Dunbar, C. and Liebich, T. and Catcheside, P. and Zajamsek, B.}, doi = {10.1093/sleep/zsab065}, journal-iso = {SLEEP}, journal = {SLEEP}, volume = {44}, unique-id = {32494219}, issn = {0161-8105}, year = {2021}, eissn = {1550-9109} } @article{MTMT:32945139, title = {The interconnected causes and consequences of sleep in the brain}, url = {https://m2.mtmt.hu/api/publication/32945139}, author = {Lewis, Laura D.}, doi = {10.1126/science.abi8375}, journal-iso = {SCIENCE}, journal = {SCIENCE}, volume = {374}, unique-id = {32945139}, issn = {0036-8075}, abstract = {Sleep is essential for brain function in a surprisingly diverse set of ways. In the short term, lack of sleep leads to impaired memory and attention; in the longer term, it produces neurological dysfunction or even death. I discuss recent advances in understanding how sleep maintains the physiological health of the brain through interconnected systems of neuronal activity and fluid flow. The neural dynamics that appear during sleep are intrinsically coupled to its consequences for blood flow, cerebrospinal fluid dynamics, and waste clearance. Recognizing these linked causes and consequences of sleep has shed new light on why sleep is important for such disparate aspects of brain function.}, year = {2021}, eissn = {1095-9203}, pages = {564-567} } @article{MTMT:31933662, title = {Microscale Physiological Events on the Human Cortical Surface}, url = {https://m2.mtmt.hu/api/publication/31933662}, author = {Paulk, Angelique C and Yang, Jimmy C and Cleary, Daniel R and Soper, Daniel J and Halgren, Milan and O’Donnell, Alexandra R and Lee, Sang Heon and Ganji, Mehran and Ro, Yun Goo and Oh, Hongseok and Hossain, Lorraine and Lee, Jihwan and Tchoe, Youngbin and Rogers, Nicholas and Kiliç, Kivilcim and Ryu, Sang Baek and Lee, Seung Woo and Hermiz, John and Gilja, Vikash and Ulbert, István and Fabó, Dániel and Thesen, Thomas and Doyle, Werner K and Devinsky, Orrin and Madsen, Joseph R and Schomer, Donald L and Eskandar, Emad N and Lee, Jong Woo and Maus, Douglas and Devor, Anna and Fried, Shelley I and Jones, Pamela S and Nahed, Brian V and Ben-Haim, Sharona and Bick, Sarah K and Richardson, Robert Mark and Raslan, Ahmed M and Siler, Dominic A and Cahill, Daniel P and Williams, Ziv M and Cosgrove, G Rees and Dayeh, Shadi A and Cash, Sydney S}, doi = {10.1093/cercor/bhab040}, journal-iso = {CEREB CORTEX}, journal = {CEREBRAL CORTEX}, volume = {31}, unique-id = {31933662}, issn = {1047-3211}, year = {2021}, eissn = {1460-2199}, pages = {3678-3700}, orcid-numbers = {Paulk, Angelique C/0000-0002-4413-3417; Ulbert, István/0000-0001-9941-9159; Fabó, Dániel/0000-0001-5141-5351; Richardson, Robert Mark/0000-0003-2620-7387} } @{MTMT:32494220, title = {Avoiding Partial Sleep: The Way for Augmentation of Brain Function}, url = {https://m2.mtmt.hu/api/publication/32494220}, author = {Pigarev, I.N. and Pigareva, M.L.}, booktitle = {Cerebellum as a CNS Hub}, doi = {10.1007/978-3-030-54564-2_10}, unique-id = {32494220}, year = {2021}, pages = {209-231} } @article{MTMT:32114098, title = {Focal lesions induce large-scale percolation of sleep-like intracerebral activity in awake humans}, url = {https://m2.mtmt.hu/api/publication/32114098}, author = {Russo, S. and Pigorini, A. and Mikulan, E. and Sarasso, S. and Rubino, A. and Zauli, F.M. and Parmigiani, S. and d'Orio, P. and Cattani, A. and Francione, S. and Tassi, L. and Bassetti, C.L.A. and Lo, Russo G. and Nobili, L. and Sartori, I. and Massimini, M.}, doi = {10.1016/j.neuroimage.2021.117964}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {234}, unique-id = {32114098}, issn = {1053-8119}, year = {2021}, eissn = {1095-9572} } @article{MTMT:31898834, title = {Homeostatic sleep regulation in the absence of the circadian sleep‐regulating component: effect of short light–dark cycles on sleep–wake stages and slow waves}, url = {https://m2.mtmt.hu/api/publication/31898834}, author = {Szalontai, Örs and Tóth, Attila István and Pethő, Máté and Keserű, Dóra and Hajnik, Tünde and Détári, László}, doi = {10.1186/s12868-021-00619-2}, journal-iso = {BMC NEUROSCI}, journal = {BMC NEUROSCIENCE}, volume = {22}, unique-id = {31898834}, issn = {1471-2202}, abstract = {Aside from the homeostatic and circadian components, light has itself an important, direct as well as indirect role in sleep regulation. Light exerts indirect sleep effect by modulating the circadian rhythms. Exposure to short light-dark cycle (LD 1:1, 1:1 h light - dark) eliminates the circadian sleep regulatory component but direct sleep effect of light could prevail. The aim of the present study was to examine the interaction between the light and the homeostatic influences regarding sleep regulation in a rat model.Spontaneous sleep-wake and homeostatic sleep regulation by sleep deprivation (SD) and analysis of slow waves (SW) were examined in Wistar rats exposed to LD1:1 condition using LD12:12 regime as control.Slow wave sleep (SWS) and REM sleep were both enhanced, while wakefulness (W) was attenuated in LD1:1. SWS recovery after 6-h total SD was more intense in LD1:1 compared to LD12:12 and SWS compensation was augmented in the bright hours. Delta power increment during recovery was caused by the increase of SW number in both cases. More SW was seen during baseline in the second half of the day in LD1:1 and after SD compared to the LD12:12. Increase of SW number was greater in the bright hours compared to the dark ones after SD in LD1:1. Lights ON evoked immediate increase in W and decrease in both SWS and REM sleep during baseline LD1:1 condition, while these changes ceased after SD. Moreover, the initial decrease seen in SWS after lights ON, turned to an increase in the next 6-min bin and this increase was stronger after SD. These alterations were caused by the change of the epoch number in W, but not in case of SWS or REM sleep. Lights OFF did not alter sleep-wake times immediately, except W, which was increased by lights OFF after SD.Present results show the complex interaction between light and homeostatic sleep regulation in the absence of the circadian component and indicate the decoupling of SW from the homeostatic sleep drive in LD1:1 lighting condition.}, keywords = {Homeostatic sleep regulation; Slow waves; Circadian sleep regulation; Short light-dark cycles; Sleep effect of light}, year = {2021}, eissn = {1471-2202}, orcid-numbers = {Szalontai, Örs/0000-0003-4833-3368; Tóth, Attila István/0000-0001-8607-8754; Hajnik, Tünde/0000-0003-0684-8136; Détári, László/0000-0002-0630-8466} } @article{MTMT:31680838, title = {The laminar profile of sleep spindles in humans}, url = {https://m2.mtmt.hu/api/publication/31680838}, author = {Ujma, Przemyslaw Péter and Hajnal, Boglárka Zsófia and Bódizs, Róbert and Gombos, Ferenc and Erőss, Loránd and Wittner, Lucia and Halgren, Eric and Cash, Sydney and Ulbert, István and Fabó, Dániel}, doi = {10.1016/j.neuroimage.2020.117587}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {226}, unique-id = {31680838}, issn = {1053-8119}, year = {2021}, eissn = {1095-9572}, orcid-numbers = {Ujma, Przemyslaw Péter/0000-0002-7981-3009; Bódizs, Róbert/0000-0001-5341-060X; Erőss, Loránd/0000-0002-5796-5546; Wittner, Lucia/0000-0001-6800-0953; Ulbert, István/0000-0001-9941-9159; Fabó, Dániel/0000-0001-5141-5351} } @article{MTMT:32114096, title = {Imaging the temporal dynamics of brain states with highly sampled fMRI}, url = {https://m2.mtmt.hu/api/publication/32114096}, author = {Yang, Z. and Lewis, L.D.}, doi = {10.1016/j.cobeha.2021.02.005}, journal-iso = {CURR OPIN BEHAV SCI}, journal = {CURRENT OPINION IN BEHAVIORAL SCIENCES}, volume = {40}, unique-id = {32114096}, issn = {2352-1546}, year = {2021}, eissn = {2352-1554}, pages = {87-95} } @article{MTMT:32114100, title = {An energy screening and morphology characterization-based hybrid expert scheme for automatic identification of micro-sleep event K-complex}, url = {https://m2.mtmt.hu/api/publication/32114100}, author = {Zhao, X. and Chen, C. and Zhou, W. and Wang, Y. and Fan, J. and Wang, Z. and Akbarzadeh, S. and Chen, W.}, doi = {10.1016/j.cmpb.2021.105955}, journal-iso = {COMPUT METH PROG BIO}, journal = {COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE}, volume = {201}, unique-id = {32114100}, issn = {0169-2607}, year = {2021}, eissn = {1872-7565} } @article{MTMT:31420465, title = {The vigilant sleeper: neural mechanisms of sensory (de)coupling during sleep}, url = {https://m2.mtmt.hu/api/publication/31420465}, author = {Andrillon, Thomas and Kouider, Sid}, doi = {10.1016/j.cophys.2019.12.002}, journal-iso = {CURR OPIN PHYSIOL}, journal = {CURRENT OPINION IN PHYSIOLOGY}, volume = {15}, unique-id = {31420465}, issn = {2468-8681}, abstract = {Sleep suppresses the ability to react to environmental demands. It has been proposed that a phenomenon of sensory isolation, whereby sensory inputs fail to reach cortical brain regions during sleep, would be responsible for this absence of responses. How and why this decoupling is implemented has been intensively investigated. However, sleepers might not be fully disconnected from their environment. We review here the empirical evidence showing that sleepers can perform a surprisingly large range of cognitive processes. We describe potential mechanisms explaining sleepers' ability to maintain covert cognitive processes as well as their suppression. Rather than being isolated from the environment, sleepers seem to enter a standby mode, allowing them to balance the monitoring of their surroundings with sensory isolation. This balance could allow sleepers to determine when to stay asleep or when to wake up, and might be essential for the fulfilment of sleep functions, notably memory consolidation.}, year = {2020}, eissn = {2468-8673}, pages = {47-59}, orcid-numbers = {Andrillon, Thomas/0000-0003-2794-8494} } @article{MTMT:31314916, title = {A Systematic Review of Closed-Loop Feedback Techniques in Sleep Studies—Related Issues and Future Directions}, url = {https://m2.mtmt.hu/api/publication/31314916}, author = {Choi, Jinyoung and Kwon, Moonyoung and Jun, Sung Chan}, doi = {10.3390/s20102770}, journal-iso = {SENSORS-BASEL}, journal = {SENSORS}, volume = {20}, unique-id = {31314916}, year = {2020}, eissn = {1424-8220} } @article{MTMT:31684574, title = {Brain networks involved in generalized periodic discharges (GPD) in post-anoxic-ischemic encephalopathy}, url = {https://m2.mtmt.hu/api/publication/31684574}, author = {De Stefano, Pia and Carboni, Margherita and Pugin, Deborah and Seeck, Margitta and Vulliemoz, Serge}, doi = {10.1016/j.resuscitation.2020.07.030}, journal-iso = {RESUSCITATION}, journal = {RESUSCITATION}, volume = {155}, unique-id = {31684574}, issn = {0300-9572}, abstract = {Aim: Generalized periodic discharge (GPD) is an EEG pattern of poor neurological outcome, frequently observed in comatose patients after cardiac arrest. The aim of our study was to identify the neuronal network generating <2.5 Hz GPD using EEG source localization and connectivity analysis.Methods: We analyzed 40 comatose adult patients with anoxic-ischemic encephalopathy, who had 19 channel-EEG recording. We computed electric source analysis based on distributed inverse solution (LAURA) and we estimated cortical activity in 82 atlas-based cortical brain regions. We applied directed connectivity analysis (Partial Directed Coherence) on these sources to estimate the main drivers.Results: Source analysis suggested that the GPD are generated in the cortex of the limbic system in the majority of patients (87.5%). Connectivity analysis revealed main drivers located in thalamus and hippocampus for the large majority of patients (80%), together with important activation also in amygdala (70%).Conclusions: We hypothesize that the anoxic-ischemic dysfunction, leading to hyperactivity of the thalamo-cortical (limbic presumably) circuit, can result in an oscillatory thalamic activity capable of inducing periodic cortical (limbic, mostly medial-temporal and orbitofrontal) discharges, similarly to the case of generalized rhythmic spike-wave discharge in convulsive or non-convulsive status epilepticus.}, keywords = {Cardiac arrest; gpd; non-convulsive status epilepticus; Anoxic-ischemic encephalopathy; Generalized periodic discharges}, year = {2020}, eissn = {1873-1570}, pages = {143-151}, orcid-numbers = {De Stefano, Pia/0000-0002-7979-0994; Carboni, Margherita/0000-0003-0426-8242; Vulliemoz, Serge/0000-0002-1877-8625} } @article{MTMT:31420466, title = {The subcortical belly of sleep: New possibilities in neuromodulation of basal ganglia?}, url = {https://m2.mtmt.hu/api/publication/31420466}, author = {Hasegawa, Harutomo and Selway, Richard and Gnoni, Valentina and Beniczky, Sándor and Williams, Steve C. R. and Kryger, Meir and Ferini-Strambi, Luigi and Goadsby, Peter and Leschziner, Guy D. and Ashkan, Keyoumars and Rosenzweig, Ivana}, doi = {10.1016/j.smrv.2020.101317}, journal-iso = {SLEEP MED REV}, journal = {SLEEP MEDICINE REVIEWS}, volume = {52}, unique-id = {31420466}, issn = {1087-0792}, abstract = {Early studies posited a relationship between sleep and the basal ganglia, but this relationship has received little attention recently. It is timely to revisit this relationship, given new insights into the functional anatomy of the basal ganglia and the physiology of sleep, which has been made possible by modern techniques such as chemogenetic and optogenetic mapping of neural circuits in rodents and intracranial recording, functional imaging, and a better understanding of human sleep disorders. We discuss the functional anatomy of the basal ganglia, and review evidence implicating their role in sleep. Whilst these studies are in their infancy, we suggest that the basal ganglia may play an integral role in the sleep-wake cycle, specifically by contributing to a thalamo-cortical-basal ganglia oscillatory network in slow-wave sleep which facilitates neural plasticity, and an active state during REM sleep which enables the enactment of cognitive and emotional networks. A better understanding of sleep mechanisms may pave the way for more effective neuromodulation strategies for sleep and basal ganglia disorders. (C) 2020 The Authors. Published by Elsevier Ltd.}, keywords = {MEMORY; sleep; basal ganglia; neuromodulation}, year = {2020}, eissn = {1532-2955} } @article{MTMT:31818739, title = {Sleep and Memory in Children}, url = {https://m2.mtmt.hu/api/publication/31818739}, author = {Hoedlmoser, K.}, doi = {10.1007/s40675-020-00194-8}, journal-iso = {CURR SLEEP MED REP}, journal = {CURRENT SLEEP MEDICINE REPORTS}, volume = {6}, unique-id = {31818739}, issn = {2198-6401}, year = {2020}, pages = {280-289} } @article{MTMT:30987110, title = {Improved identification and differentiation from epileptiform activity of human hippocampal sharp wave ripples during NREM sleep}, url = {https://m2.mtmt.hu/api/publication/30987110}, author = {Jiang, Xi and Gonzalez-Martinez, Jorge and Cash, Sydney S. and Chauvel, Patrick and Gale, John and Halgren, Eric}, doi = {10.1002/hipo.23183}, journal-iso = {HIPPOCAMPUS}, journal = {HIPPOCAMPUS}, volume = {30}, unique-id = {30987110}, issn = {1050-9631}, abstract = {In rodents, pyramidal cell firing patterns from waking may be replayed in nonrapid eye movement sleep (NREM) sleep during hippocampal sharp wave ripples (HC-SWR). In humans, HC-SWR have only been recorded with electrodes implanted to localize epileptogenicity. Here, we characterize human HC-SWR with rigorous rejection of epileptiform activity, requiring multiple oscillations and coordinated sharp waves. We demonstrated typical SWR in those rare HC recordings which lack interictal epileptiform spikes (IIS) and with no or minimal seizure involvement. These HC-SWR have a similar rate (12 min(-1) on average, variable across NREM stages and anterior/posterior HC) and apparent intra-HC topography (ripple maximum in putative stratum pyramidale, slow wave in radiatum) as rodents, though with lower frequency (85 Hz compared to 140 Hz in rodents). Similar SWR are found in HC with IIS, but no significant seizure involvement. These SWR were modulated by behavior, being largely absent (<2 min(-1)) except during NREM sleep in both Stage 2 (9 min(-1)) and Stage 3 (15 min(-1)), distinguishing them from IIS. This study quantifies the basic characteristics of a strictly selected sample of SWR recorded in relatively healthy human hippocampi.}, keywords = {Humans; sleep; intracranial electroencephalography}, year = {2020}, eissn = {1098-1063}, pages = {610-622}, orcid-numbers = {Jiang, Xi/0000-0003-4257-7628} } @article{MTMT:31420470, title = {Epidermal Growth Factor Signaling Promotes Sleep through a Combined Series and Parallel Neural Circuit}, url = {https://m2.mtmt.hu/api/publication/31420470}, author = {Konietzka, Jan and Fritz, Maximilian and Spiri, Silvan and McWhirter, Rebecca and Leha, Andreas and Palumbos, Sierra and Costa, Wagner Steuer and Oranth, Alexandra and Gottschalk, Alexander and Miller, David M. III and Hajnal, Alex and Bringmann, Henrik}, doi = {10.1016/j.cub.2019.10.048}, journal-iso = {CURR BIOL}, journal = {CURRENT BIOLOGY}, volume = {30}, unique-id = {31420470}, issn = {0960-9822}, abstract = {Sleep requires sleep-active neurons that depolarize to inhibit wake circuits. Sleep-active neurons are under the control of homeostatic mechanisms that determine sleep need. However, little is known about the molecular and circuit mechanisms that translate sleep need into the depolarization of sleep-active neurons. During many stages and conditions in C. elegans, sleep requires a sleep-active neuron called RIS. Here, we defined the transcriptome of RIS and discovered that genes of the epidermal growth factor receptor (EGFR) signaling pathway are expressed in RIS. Because of cellular stress, EGFR directly activates RIS. Activation of EGFR signaling in the ALA neuron has previously been suggested to promote sleep independently of RIS. Unexpectedly, we found that ALA activation promotes RIS depolarization. Our results suggest that ALA is a drowsiness neuron with two separable functions: (1) it inhibits specific behaviors, such as feeding, independently of RIS, (2) and it activates RIS. Whereas ALA plays a strong role in surviving cellular stress, surprisingly, RIS does not. In summary, EGFR signaling can depolarize RIS by an indirect mechanism through activation of the ALA neuron that acts upstream of the sleep-active RIS neuron and through a direct mechanism using EGFR signaling in RIS. ALA-dependent drowsiness, rather than RIS-dependent sleep bouts, appears to be important for increasing survival after cellular stress, suggesting that different types of behavioral inhibition play different roles in restoring health.}, year = {2020}, eissn = {1879-0445}, pages = {1-+}, orcid-numbers = {Spiri, Silvan/0000-0002-7124-3056; Gottschalk, Alexander/0000-0002-1197-6119; Hajnal, Alex/0000-0002-4098-3721} } @article{MTMT:31420469, title = {The human K-complex: Insights from combined scalp-intracranial EEG recordings}, url = {https://m2.mtmt.hu/api/publication/31420469}, author = {Latreille, Veronique and von Ellenrieder, Nicolas and Peter-Derex, Laure and Dubeau, Francois and Gotman, Jean and Frauscher, Birgit}, doi = {10.1016/j.neuroimage.2020.116748}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {213}, unique-id = {31420469}, issn = {1053-8119}, abstract = {Sleep spindles and K-complexes (KCs) are a hallmark of N2 sleep. While the functional significance of spindles is comparatively well investigated, there is still ongoing debate about the role of the KC: it is unclear whether it is a cortical response to an arousing stimulus (either external or internal) or whether it has sleep-promoting properties. Invasive intracranial EEG recordings from individuals with drug-resistant epilepsy offer a unique opportunity to study in-situ human brain physiology. To better understand the function of the KC, we aimed to (i) investigate the intracranial correlates of spontaneous scalp KCs, and (ii) compare the intracranial activity of scalp KCs associated or not with arousals. Whole-night recordings from adults with drug-resistant focal epilepsy who underwent combined intracranial-scalp EEG for pre-surgical evaluation at the Montreal Neurological Institute between 2010 and 2018 were selected. KCs were visually marked in the scalp and categorized according to the presence of microarousals: (i) Pre-microarousal KCs; (ii) KCs during an ongoing microarousal; and (iii) KCs without microarousal. Power in different spectral bands was computed to compare physiological intracranial EEG activity at the time of scalp KCs relative to the background, as well as to compare microarousal subcategories. A total of 1198 scalp KCs selected from 40 subjects were analyzed, resulting in 32,504 intracranial KC segments across 992 channels. Forty-seven percent of KCs were without microarousal, 30% were pre-microarousal, and 23% occurred during microarousals. All scalp KCs were accompanied by widespread cortical increases in delta band power (0.3-4 Hz) relative to the background: the highest percentages were observed in the parietal (60-65%) and frontal cortices (52-58%). Compared to KCs without microarousal, pre-microarousal KCs were accompanied by increases (66%) in beta band power (16-30 Hz) in the motor cortex, which was present before the peak of the KC. In addition, spatial distribution of spectral power changes following each KC without microarousal revealed that certain brain regions were associated with increases in delta power (25-62%) or decreases in alpha/beta power (11-24%), suggesting a sleep-promoting pattern, whereas others were accompanied by increases of higher frequencies (12-27%), suggesting an arousal-related pattern. This study shows that KCs can be generated across widespread cortical areas. Interestingly, the motor cortex shows awake-like EEG activity before the onset of KCs followed by microarousals. Our findings also highlight region-specific sleep- or arousal-promoting responses following KCs, suggesting a dual role for the human KC.}, keywords = {Polysomnography; non-rapid eye movement sleep; stereo-electroencephalography; sleep physiology; Microarousal}, year = {2020}, eissn = {1095-9572}, orcid-numbers = {Peter-Derex, Laure/0000-0002-9938-9639} } @article{MTMT:31818804, title = {Beyond K-complex binary scoring during sleep: Probabilistic classification using deep learning}, url = {https://m2.mtmt.hu/api/publication/31818804}, author = {Lechat, B. and Hansen, K. and Catcheside, P. and Zajamsek, B.}, doi = {10.1093/sleep/zsaa077}, journal-iso = {SLEEP}, journal = {SLEEP}, volume = {43}, unique-id = {31818804}, issn = {0161-8105}, year = {2020}, eissn = {1550-9109} } @article{MTMT:31420463, title = {Slow Wave Sleep Is a Promising Intervention Target for Alzheimer's Disease}, url = {https://m2.mtmt.hu/api/publication/31420463}, author = {Lee, Yee Fun and Gerashchenko, Dmitry and Timofeev, Igor and Bacskai, Brian J. and Kastanenka, Ksenia V.}, doi = {10.3389/fnins.2020.00705}, journal-iso = {FRONT NEUROSCI-SWITZ}, journal = {FRONTIERS IN NEUROSCIENCE}, volume = {14}, unique-id = {31420463}, issn = {1662-4548}, abstract = {Alzheimer's disease (AD) is the major cause of dementia, characterized by the presence of amyloid-beta plaques and neurofibrillary tau tangles. Plaques and tangles are associated with sleep-wake cycle disruptions, including the disruptions in non-rapid eye movement (NREM) slow wave sleep (SWS). Alzheimer's patients spend less time in NREM sleep and exhibit decreased slow wave activity (SWA). Consistent with the critical role of SWS in memory consolidation, reduced SWA is associated with impaired memory consolidation in AD patients. The aberrant SWA can be modeled in transgenic mouse models of amyloidosis and tauopathy. Animal models exhibited slow wave impairments early in the disease progression, prior to the deposition of amyloid-beta plaques, however, in the presence of abundant oligomeric amyloid-beta. Optogenetic rescue of SWA successfully halted the amyloid accumulation and restored intraneuronal calcium levels in mice. On the other hand, optogenetic acceleration of slow wave frequency exacerbated amyloid deposition and disrupted neuronal calcium homeostasis. In this review, we summarize the evidence and the mechanisms underlying the existence of a positive feedback loop between amyloid/tau pathology and SWA disruptions that lead to further accumulations of amyloid and tau in AD. Moreover, since SWA disruptions occur prior to the plaque deposition, SWA disruptions may provide an early biomarker for AD. Finally, we propose that therapeutic targeting of SWA in AD might lead to an effective treatment for Alzheimer's patients.}, keywords = {NREM sleep; sleep; Alzheimer's disease; slow wave activity; slow oscillations}, year = {2020}, eissn = {1662-453X} } @article{MTMT:31420467, title = {Spontaneous K-Complexes may be biomarkers of the progression of amnestic mild cognitive impairment}, url = {https://m2.mtmt.hu/api/publication/31420467}, author = {Liu, Shunjie and Pan, Junhao and Lei, Qingfeng and He, Lu and Zhong, Bingting and Meng, Yangyang and Li, Zhong}, doi = {10.1016/j.sleep.2019.10.015}, journal-iso = {SLEEP MED}, journal = {SLEEP MEDICINE}, volume = {67}, unique-id = {31420467}, issn = {1389-9457}, abstract = {Objective: Spontaneous K-complexes (SKCs), a hallmark of stage 2 sleep, have been reported to decrease in density in Alzheimer's disease (AD) patients. However, few former studies have explored the alterations in SKC characteristics in the pre-clinical phase of ADdamnestic mild cognitive impairment (aMCI). The aim of our prospective cohort study was to investigate the changing trend in SKC characteristics during the progression of aMCI.Methods: SKC density, amplitude and duration were measured in aMCI subjects and normal controls (NC) at two-year follow-up assessments by polysomnography (PSG). In sum, 22 NCs, 25 stable aMCI (sMCI) subjects and 20 progressive aMCI (pMCI) subjects finished the four follow-up PSG assessments, and their data were used for analysis.Results: SKC density and amplitude, but not duration, decreased during the follow-up assessments in both NCs and aMCI subjects, but the rate of decrease of these parameters was greater in aMCI subjects. With the progression of aMCI, significant differences in SKC density and amplitude among the three groups were observed, whereas SKC density showed no difference at the early stage of aMCI. The receiver operating characteristic (ROC) curve results demonstrated that SKC density and amplitude could distinguish aMCI subjects from NCs with high specificity and sensitivity.Conclusion: Our results suggest that SKCs decrease with ageing and the progression of aMCI, and SKC characteristics may be potential biomarkers for diagnosing aMCI. (C) 2019 Elsevier B.V. All rights reserved.}, keywords = {K-complex; Alzheimer's disease; biomarker; Progression; Amnestic mild cognitive impairment}, year = {2020}, eissn = {1878-5506}, pages = {99-109}, orcid-numbers = {Li, Zhong/0000-0002-5345-3359} } @article{MTMT:31420460, title = {Association between Loss of Sleep-specific Waves and Age, Sleep Efficiency, Body Mass Index, and Apnea-Hypopnea Index in Human N3 Sleep}, url = {https://m2.mtmt.hu/api/publication/31420460}, author = {Li, Weiguang and Duan, Ying and Yan, Jiaqing and Gao, He and Li, Xiaoli}, doi = {10.14336/AD.2019.0420}, journal-iso = {AGING DIS}, journal = {AGING AND DISEASE}, volume = {11}, unique-id = {31420460}, issn = {2152-5250}, abstract = {Sleep spindles (SS) and K-complexes (KC) play important roles in human sleep. It has been reported that age, body mass index (BMI), and apnea-hypopnea index (AHI) may influence the number of SS or KC in non-rapid-eye-movement (NREM) 2 (N2) sleep. In this study, we investigated whether the loss of SS or KC is associated with the above factors in NREM 3 (N3) sleep. A total of 152 cases were enrolled from 2013 to 2017. The correlations between the number of SS or KC in N3 sleep and participants' characteristics were analyzed using Spearman rank correlation. Chi-squared test was used to assess the effects of age, sleep efficiency, and BMI on the loss of N3 sleep, N3 spindle and N3 KC. Our results showed that there were negative correlations between the number of SS in N3 sleep with age, BMI, and AHI (P< 0.001), and similar trends were found for KC as well. The loss of SS and KC in N3 sleep was related with age, BMI, and AHI (P < 0.01), as was the loss of N3 sleep (P < 0.01). However, sleep efficiency was not related with the loss of N3 sleep, SS and KC in N3 sleep (P> 0.05). The present study supports that age, BMI, and AHI are all influencing factors of SS and KC loss in human N3 sleep, but sleep efficiency was not an influencing factor in the loss of N3 sleep and the loss of SS and KC in N3 sleep.}, keywords = {AGE; K-complex; sleep spindle; Body Mass Index; apnea–hypopnea index; sleep efficiency}, year = {2020}, eissn = {2152-5250}, pages = {73-81} } @article{MTMT:31420461, title = {A wake-active locomotion circuit depolarizes a sleep-active neuron to switch on sleep}, url = {https://m2.mtmt.hu/api/publication/31420461}, author = {Maluck, Elisabeth and Busack, Inka and Besseling, Judith and Masurat, Florentin and Turek, Michal and Busch, Karl Emanuel and Bringmann, Henrik}, doi = {10.1371/journal.pbio.3000361}, journal-iso = {PLOS BIOL}, journal = {PLOS BIOLOGY}, volume = {18}, unique-id = {31420461}, issn = {1544-9173}, abstract = {Sleep-active neurons depolarize during sleep to suppress wakefulness circuits. Wake-active wake-promoting neurons in turn shut down sleep-active neurons, thus forming a bipartite flip-flop switch. However, how sleep is switched on is unclear because it is not known how wakefulness is translated into sleep-active neuron depolarization when the system is set to sleep. Using optogenetics in Caenorhabditis elegans, we solved the presynaptic circuit for depolarization of the sleep-active RIS neuron during developmentally regulated sleep, also known as lethargus. Surprisingly, we found that RIS activation requires neurons that have known roles in wakefulness and locomotion behavior. The RIM interneurons-which are active during and can induce reverse locomotion-play a complex role and can act as inhibitors of RIS when they are strongly depolarized and as activators of RIS when they are modestly depolarized. The PVC command interneurons, which are known to promote forward locomotion during wakefulness, act as major activators of RIS. The properties of these locomotion neurons are modulated during lethargus. The RIMs become less excitable. The PVCs become resistant to inhibition and have an increased capacity to activate RIS. Separate activation of neither the PVCs nor the RIMs appears to be sufficient for sleep induction; instead, our data suggest that they act in concert to activate RIS. Forward and reverse circuit activity is normally mutually exclusive. Our data suggest that RIS may be activated at the transition between forward and reverse locomotion states, perhaps when both forward (PVC) and reverse (including RIM) circuit activity overlap. While RIS is not strongly activated outside of lethargus, altered activity of the locomotion interneurons during lethargus favors strong RIS activation and thus sleep. The control of sleep-active neurons by locomotion circuits suggests that sleep control may have evolved from locomotion control. The flip-flop sleep switch in C. elegans thus requires an additional component, wake-active sleep-promoting neurons that translate wakefulness into the depolarization of a sleep-active neuron when the worm is sleepy. Wake-active sleep-promoting circuits may also be required for sleep state switching in other animals, including in mammals.}, year = {2020}, eissn = {1545-7885}, orcid-numbers = {Busch, Karl Emanuel/0000-0001-7886-3226} } @article{MTMT:31420458, title = {Multitaper-based method for automatic k-complex detection in human sleep EEG}, url = {https://m2.mtmt.hu/api/publication/31420458}, author = {Oliveira, Gustavo H. B. S. and Coutinho, Luciano R. and da Silva, Josenildo C. and Pinto, Ivan J. P. and Ferreira, Julia M. S. and Silva, Francisco J. S. and Santos, Davi V and Teles, Ariel S.}, doi = {10.1016/j.eswa.2020.113331}, journal-iso = {EXPERT SYST APPL}, journal = {EXPERT SYSTEMS WITH APPLICATIONS}, volume = {151}, unique-id = {31420458}, issn = {0957-4174}, abstract = {In this paper, we propose a novel method for automatic k-complex (KC) detection in human sleep EEG, named MT-KCD. KCs are slow oscillations in the EEG signal characterized by a well-delineated, negative, sharp waves immediately followed by a positive component standing out from the background, with high-amplitude and total duration >= 0.5 s. Among the important aspects of the KC are its homeostatic and reactive functions in the brain, functioning as a sleep protection mechanism, and its practical use as a marker of N2 sleep stage during sleep studies. Given the importance of the KC, and the effort required from human experts to analyze EEG recordings visually, some recent research works have proposed automatic methods for KC detection. In comparison with existing methods, a key feature and novelty of MT-KCD is the use of multitaper spectral analysis to pre-process the EEG signal and automatically extract candidate KCs from it (characterized as 0-4 Hz power concentrations standing out from the background). After extraction, candidates are accepted/rejected depending on time domain characteristics (peak-to-peak amplitude >= 75 mu V, duration <= 2 s). The method overall time complexity is O(N logN). Regarding effectiveness, we have evaluated MT-KCD by using a public KC database (DREAMS) consisting of ten polysomnographic recordings of healthy patients (6 female and 4 male subjects with age range 20-47 years) partially annotated by two experts. Results have shown that MT-KCD improves detection metrics, especially F1 and F2 scores (harmonic averages of recall and precision), when compared to existing methods. Besides, improving F1 and F2 scores, MT-KCD also contributes to the automatic analysis of sleep EEG multitaper spectrograms, a technique recently proposed by researchers in the area of sleep studies as a complement to the traditional hypnogram (sleep stages diagram). (C) 2020 Elsevier Ltd. All rights reserved.}, keywords = {Spectral analysis; K-complex; Electroencephalogram; Multitaper spectrogram; Sleep study}, year = {2020}, eissn = {1873-6793} } @article{MTMT:32114103, title = {Local sleep-like cortical reactivity in the awake brain after focal injury}, url = {https://m2.mtmt.hu/api/publication/32114103}, author = {Sarasso, S. and D'Ambrosio, S. and Fecchio, M. and Casarotto, S. and Viganò, A. and Landi, C. and Mattavelli, G. and Gosseries, O. and Quarenghi, M. and Laureys, S. and Devalle, G. and Rosanova, M. and Massimini, M.}, doi = {10.1093/brain/awaa338}, journal-iso = {BRAIN}, journal = {BRAIN}, volume = {143}, unique-id = {32114103}, issn = {0006-8950}, year = {2020}, eissn = {1460-2156}, pages = {3672-3684} } @article{MTMT:31323105, title = {Spatio-temporal properties of sleep slow waves and implications for development}, url = {https://m2.mtmt.hu/api/publication/31323105}, author = {Timofeev, Igor and Schoch, Sarah F and LeBourgeois, Monique K and Huber, Reto and Riedner, Brady A and Kurth, Salome}, doi = {10.1016/j.cophys.2020.01.007}, journal-iso = {CURR OPIN PHYSIOL}, journal = {CURRENT OPINION IN PHYSIOLOGY}, volume = {15}, unique-id = {31323105}, issn = {2468-8681}, year = {2020}, eissn = {2468-8673}, pages = {172-182} } @article{MTMT:31420464, title = {EEG microstates are correlated with brain functional networks during slow -wave sleep}, url = {https://m2.mtmt.hu/api/publication/31420464}, author = {Xu, Jing and Pan, Yu and Zhou, Shuqin and Zou, Guangyuan and Liu, Jiayi and Su, Zihui and Zou, Qihong and Gao, Jia-Hong}, doi = {10.1016/j.neuroimage.2020.116786}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {215}, unique-id = {31420464}, issn = {1053-8119}, year = {2020}, eissn = {1095-9572} } @article{MTMT:31420468, title = {Functional MRI of arousals in nonrapid eye movement sleep}, url = {https://m2.mtmt.hu/api/publication/31420468}, author = {Zou, Guangyuan and Xu, Jing and Zhou, Shuqin and Liu, Jiayi and Su, Zi Hui and Zou, Qihong and Gao, Jia-Hong}, doi = {10.1093/sleep/zsz218}, journal-iso = {SLEEP}, journal = {SLEEP}, volume = {43}, unique-id = {31420468}, issn = {0161-8105}, abstract = {Arousals commonly occur during human sleep and have been associated with several sleep disorders. Arousals are characterized as an abrupt electroencephalography (EEG) frequency change to higher frequencies during sleep. However, the human brain regions involved in arousal are not yet clear. Simultaneous EEG and functional magnetic resonance imaging (fMRI) data were recorded during the early portion of the sleep period in healthy young adults. Arousals were identified based on the EEG data, and fMRI signal changes associated with 83 arousals from 19 subjects were analyzed. Subcortical regions, including the midbrain, thalamus, basal ganglia, and cerebellum, were activated with arousal. Cortices, including the temporal gyrus, occipital gyrus, and frontal gyrus, were deactivated with arousal. The activations associated with arousal in the subcortical regions were consistent with previous findings of subcortical involvement in behavioral arousal and consciousness. Cortical deactivations may serve as a mechanism to direct incoming sensory stimuli to specific brain regions, thereby monitoring environmental perturbations during sleep.}, keywords = {ACTIVATION; EEG; arousal; sleep; DEACTIVATION; FMRI}, year = {2020}, eissn = {1550-9109} } @article{MTMT:30984008, title = {Oscillating circuitries in the sleeping brain}, url = {https://m2.mtmt.hu/api/publication/30984008}, author = {Adamantidis, Antoine R. and Herrera, Carolina Gutierrez and Gent, Thomas C.}, doi = {10.1038/s41583-019-0223-4}, journal-iso = {NAT REV NEUROSCI}, journal = {NATURE REVIEWS NEUROSCIENCE}, volume = {20}, unique-id = {30984008}, issn = {1471-003X}, abstract = {Brain activity during sleep is characterized by circuit-specific oscillations, including slow waves, spindles and theta waves, which are nested in thalamocortical or hippocampal networks. A major challenge is to determine the relationships between these oscillatory activities and the identified networks of sleep-promoting and wake-promoting neurons distributed throughout the brain. Improved understanding of the neurobiological mechanisms that orchestrate sleep-related oscillatory activities, both in time and space, is expected to generate further insight into the delineation of sleep states and their functions.}, year = {2019}, eissn = {1471-0048}, pages = {746-762} } @article{MTMT:31126707, title = {The asynchronous state’s relation to large-scale potentials in cortex}, url = {https://m2.mtmt.hu/api/publication/31126707}, author = {Alishbayli, A. and Tichelaar, J.G. and Gorska, U. and Cohen, M.X. and Englitz, B.}, doi = {10.1152/jn.00013.2019}, journal-iso = {J NEUROPHYSIOL}, journal = {JOURNAL OF NEUROPHYSIOLOGY}, volume = {122}, unique-id = {31126707}, issn = {0022-3077}, abstract = {Understanding the relation between large-scale potentials (M/EEG) and their underlying neural activity can improve the precision of research and clinical diagnosis. Recent insights into cortical dynamics highlighted a state of strongly reduced spike count correlations, termed the asynchronous state (AS). The AS has received considerable attention from experimenters and theorists alike, regarding its implications for cortical dynamics and coding of information. However, how reconcilable are these vanishing correlations in the AS with large-scale potentials such as M/EEG observed in most experiments? Typically the latter are assumed to be based on underlying correlations in activity, in particular between subthreshold potentials. We survey the occurrence of the AS across brain states, regions. and layers and argue for a reconciliation of this seeming disparity: large-scale potentials are either observed, first, at transitions between cortical activity states, which entail transient changes in population firing rate, as well as during the AS. and, second, on the basis of sufficiently large, asynchronous populations that only need to exhibit weak correlations in activity. Cells with no or little spiking activity can contribute to large-scale potentials via their subthreshold currents, while they do not contribute to the estimation of spiking correlations, defining the AS. Further-more. third, the AS occurs only within particular cortical regions and layers associated with the currently selected modality, allowing for correlations at other times and between other areas and layers.}, year = {2019}, eissn = {1522-1598}, pages = {2206-2219} } @article{MTMT:31004917, title = {Distributed slow-wave dynamics during sleep predict memory consolidation and its impairment in schizophrenia}, url = {https://m2.mtmt.hu/api/publication/31004917}, author = {Bartsch, Ullrich and Simpkin, Andrew J. and Demanuele, Charmaine and Wamsley, Erin and Marston, Hugh M. and Jones, Matthew W.}, doi = {10.1038/s41537-019-0086-8}, journal-iso = {NPJ SCHIZOPHR}, journal = {NPJ SCHIZOPHRENIA}, volume = {5}, unique-id = {31004917}, abstract = {The slow waves (SW) of non-rapid eye movement (NREM) sleep reflect neocortical components of network activity during sleep-dependent information processing; their disruption may therefore impair memory consolidation. Here, we quantify sleep-dependent consolidation of motor sequence memory, alongside sleep EEG-derived SW properties and synchronisation, and SW-spindle coupling in 21 patients suffering from schizophrenia and 19 healthy volunteers. Impaired memory consolidation in patients culminated in an overnight improvement in motor sequence task performance of only 1.6%, compared with 15% in controls. During sleep after learning, SW amplitudes and densities were comparable in healthy controls and patients. However, healthy controls showed a significant 45% increase in frontal-to-occipital SW coherence during sleep after motor learning in comparison with a baseline night (baseline: 0.22 +/- 0.05, learning: 0.32 +/- 0.05); patient EEG failed to show this increase (baseline: 0.22 +/- 0.04, learning: 0.19 +/- 0.04). The experience-dependent nesting of spindles in SW was similarly disrupted in patients: frontal-to-occipital SW-spindle phase-amplitude coupling (PAC) significantly increased after learning in healthy controls (modulation index baseline: 0.17 +/- 0.02, learning: 0.22 +/- 0.02) but not in patients (baseline: 0.13 +/- 0.02, learning: 0.14 +/- 0.02). Partial least-squares regression modelling of coherence and PAC data from all electrode pairs confirmed distributed SW coherence and SW-spindle coordination as superior predictors of overnight memory consolidation in healthy controls but not in patients. Quantifying the full repertoire of NREM EEG oscillations and their long-range covariance therefore presents learning-dependent changes in distributed SW and spindle coordination as fingerprints of impaired cognition in schizophrenia.}, year = {2019}, eissn = {2334-265X} } @{MTMT:31327731, title = {Local Patterns of Sleep and Wakefulness}, url = {https://m2.mtmt.hu/api/publication/31327731}, author = {Bernardi, G. and Siclari, F.}, booktitle = {Handbook of Sleep Research}, doi = {10.1016/B978-0-12-813743-7.00003-7}, volume = {30}, unique-id = {31327731}, keywords = {Brain; human; ADAPTATION; EEG; NREM sleep; sleep spindle; Insomnia; wakefulness; sleep; sleep; REM sleep; Electroencephalogram; Consciousness; dreaming; dreaming; SPINDLES; parasomnia; Slow wave}, year = {2019}, pages = {33-47} } @article{MTMT:30779787, title = {A fast and general method to empirically estimate the complexity of brain responses to transcranial and intracranial stimulations}, url = {https://m2.mtmt.hu/api/publication/30779787}, author = {Comolatti, Renzo and Pigorini, Andrea and Casarotto, Silvia and Fecchio, Matteo and Faria, Guilherme and Sarasso, Simone and Rosanova, Mario and Gosseries, Olivia and Boly, Melanie and Bodart, Olivier and Ledoux, Didier and Brichant, Jean-Francois and Nobili, Lino and Laureys, Steven and Tononi, Giulio and Massimini, Marcello and Casali, Adenauer G.}, doi = {10.1016/j.brs.2019.05.013}, journal-iso = {BRAIN STIMUL}, journal = {BRAIN STIMULATION}, volume = {12}, unique-id = {30779787}, issn = {1935-861X}, abstract = {Background: The Perturbational Complexity Index (PCI) was recently introduced to assess the capacity of thalamocortical circuits to engage in complex patterns of causal interactions. While showing high accuracy in detecting consciousness in brain-injured patients, PCI depends on elaborate experimental setups and offline processing, and has restricted applicability to other types of brain signals beyond transcranial magnetic stimulation and high-density EEG (TMS/hd-EEG) recordings.Objective: We aim to address these limitations by introducing PCIST, a fast method for estimating perturbational complexity of any given brain response signal.Methods: PCIST is based on dimensionality reduction and state transitions (ST) quantification of evoked potentials. The index was validated on a large dataset of TMS/hd-EEG recordings obtained from 108 healthy subjects and 108 brain-injured patients, and tested on sparse intracranial recordings (SEEG) of 9 patients undergoing intracranial single-pulse electrical stimulation (SPES) during wakefulness and sleep.Results: When calculated on TMS/hd-EEG potentials, PCIST performed with the same accuracy as the original PCI, while improving on the previous method by being computed in less than a second and requiring a simpler set-up. In SPES/SEEG signals, the index was able to quantify a systematic reduction of intracranial complexity during sleep, confirming the occurrence of state-dependent changes in the effective connectivity of thalamocortical circuits, as originally assessed through TMS/hd-EEG.Conclusions: PCIST represents a fundamental advancement towards the implementation of a reliable and fast clinical tool for the bedside assessment of consciousness as well as a general measure to explore the neuronal mechanisms of loss/recovery of brain complexity across scales and models. (C) 2019 Elsevier Inc. All rights reserved.}, keywords = {EEG; Consciousness; transcranial magnetic stimulation; Intracranial; single pulse electrical stimulation; Brain complexity}, year = {2019}, eissn = {1876-4754}, pages = {1280-1289}, orcid-numbers = {Sarasso, Simone/0000-0001-9984-4710} } @article{MTMT:31327730, title = {Functional connectivity dynamics slow with descent from wakefulness to sleep}, url = {https://m2.mtmt.hu/api/publication/31327730}, author = {El-Baba, M. and Lewis, D.J. and Fang, Z. and Owen, A.M. and Fogel, S.M. and Morton, J.B.}, doi = {10.1371/journal.pone.0224669}, journal-iso = {PLOS ONE}, journal = {PLOS ONE}, volume = {14}, unique-id = {31327730}, issn = {1932-6203}, abstract = {The transition from wakefulness to sleep is accompanied by widespread changes in brain functioning. Here we investigate the implications of this transition for interregional functional connectivity and their dynamic changes over time. Simultaneous EEG-fMRI was used to measure brain functional activity of 21 healthy participants as they transitioned from wakefulness into sleep. fMRI volumes were independent component analysis (ICA)-decomposed, yielding 42 neurophysiological sources. Static functional connectivity (FC) was estimated from independent component time courses. A sliding window method and k-means clustering (k = 7, L2-norm) were used to estimate dynamic FC. Static FC in Wake and Stage-2 Sleep (NREM2) were largely similar. By contrast, FC dynamics across wake and sleep differed, with transitions between FC states occurring more frequently during wakefulness than during NREM2. Evidence of slower FC dynamics during sleep is discussed in relation to sleep-related reductions in effective connectivity and synaptic strength. © 2019 El-Baba et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.}, keywords = {Adult; Adult; Female; Female; Male; Male; Humans; ARTICLE; human; Brain Mapping; Brain Mapping; physiology; controlled study; nuclear magnetic resonance imaging; Magnetic Resonance Imaging; functional magnetic resonance imaging; clinical article; wakefulness; wakefulness; wakefulness; human experiment; Electroencephalography; Electroencephalography; sleep; sleep; Electroencephalogram; synapse; DECOMPOSITION; Young Adult; Young Adult; Diagnostic Imaging; Nerve Net; nerve cell network; Independent component analysis; functional connectivity; stage 2 sleep; k means clustering}, year = {2019}, eissn = {1932-6203} } @article{MTMT:3406025, title = {Fine-scale mapping of cortical laminar activity during sleep slow oscillations using high-density linear silicon probes}, url = {https://m2.mtmt.hu/api/publication/3406025}, author = {Fiáth, Richárd and Raducanu, BC and Musa, S and Andrei, A and Lopez, CM and Welkenhuysen, M and Ruther, P and Aarts, A and Ulbert, István}, doi = {10.1016/j.jneumeth.2018.08.020}, journal-iso = {J NEUROSCI METH}, journal = {JOURNAL OF NEUROSCIENCE METHODS}, volume = {316}, unique-id = {3406025}, issn = {0165-0270}, keywords = {Slow oscillation; neocortex; single-unit activity; laminar recording; SLOW-WAVE ACTIVITY; high-density silicon probe}, year = {2019}, eissn = {1872-678X}, pages = {58-70}, orcid-numbers = {Fiáth, Richárd/0000-0001-8732-2691; Ulbert, István/0000-0001-9941-9159} } @article{MTMT:31216835, title = {Bridging Single Neuron Dynamics to Global Brain States}, url = {https://m2.mtmt.hu/api/publication/31216835}, author = {Goldman, Jennifer S. and Tort-Colet, Nuria and di Volo, Matteo and Susin, Eduarda and Boute, Jules and Dali, Melissa and Carlu, Mallory and Nghiem, Trang-Anh and Gorski, Tomasz and Destexhe, Alain}, doi = {10.3389/fnsys.2019.00075}, journal-iso = {FRONT SYST NEUROSCI}, journal = {FRONTIERS IN SYSTEMS NEUROSCIENCE}, volume = {13}, unique-id = {31216835}, abstract = {Biological neural networks produce information backgrounds of multi-scale spontaneous activity that become more complex in brain states displaying higher capacities for cognition, for instance, attentive awake versus asleep or anesthetized states. Here, we review brain state-dependent mechanisms spanning ion channel currents (microscale) to the dynamics of brain-wide, distributed, transient functional assemblies (macroscale). Not unlike how microscopic interactions between molecules underlie structures formed in macroscopic states of matter, using statistical physics, the dynamics of microscopic neural phenomena can be linked to macroscopic brain dynamics through mesoscopic scales. Beyond spontaneous dynamics, it is observed that stimuli evoke collapses of complexity, most remarkable over high dimensional, asynchronous, irregular background dynamics during consciousness. In contrast, complexity may not be further collapsed beyond synchrony and regularity characteristic of unconscious spontaneous activity. We propose that increased dimensionality of spontaneous dynamics during conscious states supports responsiveness, enhancing neural networks' emergent capacity to robustly encode information over multiple scales.}, keywords = {Cerebral Cortex; coupling; NEURAL NETWORK MODELS; Computational neuroscience; membrane biophysics; Mean-field models; low-dimensional manifold; desynchronized}, year = {2019}, eissn = {1662-5137} } @article{MTMT:30901044, title = {The heritability of the human K-complex: A twin study}, url = {https://m2.mtmt.hu/api/publication/30901044}, author = {Gorgoni, M. and Reda, F. and D'Atri, A. and Scarpelli, S. and Ferrara, M. and De, Gennaro L.}, doi = {10.1093/sleep/zsz053}, journal-iso = {SLEEP}, journal = {SLEEP}, volume = {42}, unique-id = {30901044}, issn = {0161-8105}, year = {2019}, eissn = {1550-9109} } @article{MTMT:31004920, title = {Improvement of Parasomnias After Treatment of Restless Leg Syndrome/Periodic Limb Movement Disorder in Children}, url = {https://m2.mtmt.hu/api/publication/31004920}, author = {Gurbani, Neepa and Dye, Thomas J. and Dougherty, Kyle and Jain, Sejal and Horn, Paul S. and Simakajornboon, Narong}, doi = {10.5664/jcsm.7766}, journal-iso = {J CLIN SLEEP MED (JCSM)}, journal = {JOURNAL OF CLINICAL SLEEP MEDICINE (JCSM)}, volume = {15}, unique-id = {31004920}, issn = {1550-9389}, abstract = {Study Objectives: Previous studies have shown that non-rapid eye movement (NREM) sleep parasomnias commonly coexist with restless legs syndrome (RLS) and periodic limb movement disorder (PLMD) in children, leading to speculation that RLS/PLMD may precipitate or worsen parasomnias. However, there are limited data about the effect of the treatment of RLS/PLMD on parasomnias in children. Hence, we performed this study to determine whether the treatment of RLS/PLMD with oral iron therapy is associated with improvement of parasomnias in children.Methods: A retrospective database was created for children with RLS/PLMD who were treated with iron therapy. These participants were followed for at least 1 year at Cincinnati Children's Hospital Medical Center. All participants had ferritin level testing and were treated with iron therapy. In addition, all participants underwent polysomnography before starting iron therapy for RLS/PLMD except for one participant who was already on iron but required a higher dose. Most participants underwent polysomnography after iron therapy.Results: A total of 226 participants were identified with the diagnosis of RLS/PLMD. Of these, 50 had parasomnias and 30 of them were treated with iron therapy. Of the 30 participants, RLS symptoms improved in 15 participants (50%) and resolution of parasomnias was noted in 12 participants (40%) participants after iron therapy. Repeat polysomnography after iron therapy was performed in 21 participants (70%). After iron therapy, there was a significant decrease in periodic limb movement index (17.2 +/- 8.8 [before] versus 6.7 +/- 7.3 [after] events/h, P <.001). In addition, there were significant decreases in PLMS (24.52 +/- 9.42 [before] versus 7.50 +/- 7.18 [after] events/h, P <.0001), PLMS-related arousals (4.71 +/- 1.81 [before] versus 1.35 +/- 1.43 [after] events/h, P <.0001), and total arousals (11.65 +/- 5.49 [before] versus 8.94 +/- 3.65 [after] events/h, P <.01) after iron therapy.Conclusions: Parasomnias are common in our cohort of children with RLS/PLMD. Iron therapy was associated with a significant improvement in periodic limb movement index, RLS symptoms, and resolution of a significant proportion of NREM sleep parasomnias, suggesting that RLS/PLMD may precipitate NREM sleep parasomnia.}, keywords = {Restless leg syndrome; periodic limb movement disorder; Parasomnias}, year = {2019}, eissn = {1550-9397}, pages = {743-748} } @article{MTMT:31004919, title = {The Emergence of Spindles and K-Complexes and the Role of the Dorsal Caudal Part of the Anterior Cingulate as the Generator of K-Complexes}, url = {https://m2.mtmt.hu/api/publication/31004919}, author = {Ioannides, Andreas A. and Liu, Lichan and Kostopoulos, George K.}, doi = {10.3389/fnins.2019.00814}, journal-iso = {FRONT NEUROSCI-SWITZ}, journal = {FRONTIERS IN NEUROSCIENCE}, volume = {13}, unique-id = {31004919}, issn = {1662-4548}, abstract = {The large multicomponent K-complex (KC) and the rhythmic spindle are the hallmarks of non-rapid eye movement (NREM)-2 sleep stage. We studied with magnetoencephalography (MEG) the progress of light sleep (NREM-1 and NREM-2) and emergence of KCs and spindles. Seven periods of interest (POI) were analyzed: wakefulness, the two quiet "core" periods of light sleep (periods free from any prominent phasic or oscillatory events) and four periods before and during spindles and KCs. For each POI, eight 2-s (1250 time slices) segments were used. We employed magnetic field tomography (MFT) to extract an independent tomographic estimate of brain activity from each MEG data sample. The spectral power was then computed for each voxel in the brain for each segment of each POI. The sets of eight maps from two POIs were contrasted using a voxel-by-voxel t-test. Only increased spectral power was identified in the four key contrasts between POIs before and during spindles and KCs versus the NREM2 core. Common increases were identified for all four subjects, especially within and close to the anterior cingulate cortex (ACC). These common increases were widespread for low frequencies, while for higher frequencies they were focal, confined to specific brain areas. For the pre-KC POI, only one prominent increase was identified, confined to the theta/alpha bands in a small area in the dorsal caudal part of ACC (dcACC). During KCs, the activity in this area grows in intensity and extent (in space and frequency), filling the space between the areas that expanded their low frequency activity (in the delta band) during NREM2 compared to NREM1. Our main finding is that prominent spectral power increases before NREM2 graphoelements are confined to the dcACC, and only for KCs, sharing common features with changes of activity in dcACC of the well-studied error related negativity (ERN). ERN is seen in awake state, in perceptual conflict and situations where there is a difference between expected and actual environmental or internal events. These results suggest that a KC is the sleep side of the awake state ERN, both serving their putative sentinel roles in the frame of the saliency network.}, keywords = {sleep; magnetoencephalography; SPINDLES; K-complexes; magnetic field tomography; error related negativity}, year = {2019}, eissn = {1662-453X} } @article{MTMT:30987108, title = {Coordination of Human Hippocampal Sharpwave Ripples during NREM Sleep with Cortical Theta Bursts, Spindles, Downstates, and Upstates}, url = {https://m2.mtmt.hu/api/publication/30987108}, author = {Jiang, Xi and Gonzalez-Martinez, Jorge and Halgren, Eric}, doi = {10.1523/JNEUROSCI.2857-18.2019}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {39}, unique-id = {30987108}, issn = {0270-6474}, abstract = {In rodents, waking firing patterns replay in NREM sleep during hippocampal sharpwave ripples (HC-SWRs), correlated with neocortical graphoelements (NC-GEs). NC-GEs include theta bursts, spindles, downstates, and upstates. In humans, consolidation during sleep is correlated with scalp-recorded spindles and downstates/upstates, but HC-SWRs cannot be recorded noninvasively. Here we show in humans of both sexes that HC-SWRs are highly correlated with NC-GEs during NREM, with significantly more related HC-SWRs/NC-GEs for downstates or upstates than theta bursts or spindles, in N2 than N3, in posterior than anterior HC, in frontal than occipital cortex, and ipsilaterally than contralaterally. The preferences interacted (e.g., frontal spindles co-occurred frequently with posterior HC-SWRs in N2). These preferred GEs, stages, and locations for HC-SWR/NC-GE interactions may index selective consolidation activity, although that was not tested in this study. SWR recorded in different HC regions seldom co-occurred, and were related to GE in different cortical areas, showingthat HC-NC interact in multiple transient, widespread but discrete, networks. NC-GEs tend to occur with consistent temporal relationships to HC-SW Rs, and to each other. Cortical theta bursts usually precede HC-SWRs, where they may help define cortical input triggering HC-SWR firing. HC-SWRs often follow cortical downstate onsets, surrounded by locally decreased broadband power, suggesting a mechanism synchronizing cortical, thalamic, and hippocampal activities. Widespread cortical upstates and spindles follow HC-SWRs, consistent with the hypothesized contribution by hippocampal firing during HC-SW Rs to cortical firing-patterns during upstates and spindles. Overall, our results describe how hippocampal and cortical oscillations are coordinated in humans during events that are critical for memory consolidation in rodents.}, keywords = {MEMORY; hippocampus; human; Electrophysiology; sleep; neocortex}, year = {2019}, eissn = {1529-2401}, pages = {8744-8761}, orcid-numbers = {Jiang, Xi/0000-0003-4257-7628} } @article{MTMT:30987109, title = {Posterior Hippocampal Spindle Ripples Co-occur with Neocortical Theta Bursts and Downstates-Upstates, and Phase-Lock with Parietal Spindles during NREM Sleep in Humans}, url = {https://m2.mtmt.hu/api/publication/30987109}, author = {Jiang, Xi and Gonzalez-Martinez, Jorge and Halgren, Eric}, doi = {10.1523/JNEUROSCI.2858-18.2019}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {39}, unique-id = {30987109}, issn = {0270-6474}, abstract = {Human anterior and posterior hippocampus (aHC, pHC) differ in connectivity and behavioral correlates. Here we report physiological differences in humans of both sexes. During NREM sleep, the human hippocampus generates sharpwave ripples (SWRs) similar to those which in rodents mark memory replay. Weshow that while pHC generates SWRs, it also generates approximately as many spindle ripples (SSR: ripples phase-locked to local spindles). In contrast, SSRs are rare in aHC. Like SWRs, SSRs often co-occur with neocortical theta bursts (TBs), downstates (DSs), sleep spindles (SSs), and upstates (USs), which coordinate cortico-hippocampal interactions and facilitate consolidation in rodents. SWRs co-occur with these waves in widespread cortical areas, especially frontocentral. These waves typically occur in the sequence TB-DS-SS-US, with SWRs usually occurring before SS-US. In contrast, SSRs occur similar to 350 ms later, with a strong preference for co-occurrence with posterior-parietal SSs. pHC-SSs were strongly phase-locked with parietal-SSs, and pHC-SSRs were phase-coupled with pHC-SSs and parietal-SSs. HumanSWRs (and associated replay events, if any) are separated by similar to 5 s on average, whereas ripples on successive SSR peaks are separated by only similar to 80 ms. These distinctive physiological properties of pHC-SSR enable an alternative mechanism for hippocampal engagement with neocortex.}, keywords = {MEMORY; hippocampus; human; Electrophysiology; sleep; neocortex}, year = {2019}, eissn = {1529-2401}, pages = {8949-8968}, orcid-numbers = {Jiang, Xi/0000-0003-4257-7628} } @article{MTMT:30775442, title = {Remembering to forget: A dual role for sleep oscillations in memory consolidation and forgetting}, url = {https://m2.mtmt.hu/api/publication/30775442}, author = {Langille, J.J.}, doi = {10.3389/fncel.2019.00071}, journal-iso = {FRONT CELL NEUROSCI}, journal = {FRONTIERS IN CELLULAR NEUROSCIENCE}, volume = {13}, unique-id = {30775442}, issn = {1662-5102}, abstract = {It has been known since the time of patient H. M. and Karl Lashley’s equipotentiality studies that the hippocampus and cortex serve mnestic functions. Current memory models maintain that these two brain structures accomplish unique, but interactive, memory functions. Specifically, most modeling suggests that memories are rapidly acquired during waking experience by the hippocampus, before being later consolidated into the cortex for long-term storage. Sleep has been shown to be critical for the transfer and consolidation of memories in the cortex. Like memory consolidation, a role for sleep in adaptive forgetting has both historical precedent, as Francis Crick suggested in 1983 that sleep was for “reverse-learning,” and recent empirical support. In this article I review the evidence indicating that the same brain activity involved in sleep replay associated memory consolidation is responsible for sleep-dependent forgetting. In reviewing the literature, it became clear that both a cellular mechanism for systems consolidation and an agreed upon general, as well as cellular, mechanism for sleep-dependent forgetting is seldom discussed or is lacking. I advocate here for a candidate cellular systems consolidation mechanism wherein changes in calcium kinetics and the activation of consolidative signaling cascades arise from the triple phase locking of non-rapid eye movement sleep (NREMS) slow oscillation, sleep spindle and sharp-wave ripple rhythms. I go on to speculatively consider several sleep stage specific forgetting mechanisms and conclude by discussing a notional function of NREM-rapid eye movement sleep (REMS) cycling. The discussed model argues that the cyclical organization of sleep functions to first lay down and edit and then stabilize and integrate engrams. All things considered, it is increasingly clear that hallmark sleep stage rhythms, including several NREMS oscillations and the REMS hippocampal theta rhythm, serve the dual function of enabling simultaneous memory consolidation and adaptive forgetting. Specifically, the same sleep rhythms that consolidate new memories, in the cortex and hippocampus, simultaneously organize the adaptive forgetting of older memories in these brain regions. © 2019 Langille.}, keywords = {Adult; ARTICLE; signal transduction; human; hippocampus theta rhythm; brain region; oscillation; learning; learning; REM; NREM; brain cortex; nonREM sleep; sleep spindle; sleep spindle; sleep pattern; memory consolidation; wakefulness; synapse; human cell; calcium mobilization; cellular; synaptic; Sharp wave}, year = {2019}, eissn = {1662-5102} } @inproceedings{MTMT:31572283, title = {Causal Connectivity According to Conscious Experience in Non-Rapid Eye Movement Sleep}, url = {https://m2.mtmt.hu/api/publication/31572283}, author = {Lee, Minji and Baird, Benjamin and Gosseries, Olivia and Nieminen, Jaakko O. and Boly, Melanie and Tononi, Giulio and Lee, Seong-Whan}, booktitle = {2019 IEEE International Conference on Systems, Man and Cybernetics (SMC)}, doi = {10.1109/SMC.2019.8914541}, unique-id = {31572283}, abstract = {The understanding of human consciousness based on brain connectivity is considered important for brain-machine interfacing. In this study, we investigated changes in causal connectivity in electroencephalography data related to conscious and unconscious experiences during non-rapid eye movement sleep after parietal transcranial magnetic stimulation (TMS). A serial awakening paradigm was used to determine whether subjects had had a conscious experience or not. We calculated direct transfer function (DTF) as a measure of effective connectivity in five frequency bands focusing on frontal and parietal- occipital regions. The DTF showed significant differences in frontal-to-parietal flow between reported unconsciousness and consciousness. During the first 100 ms after TMS, the outward links of the parietal region at low frequencies were higher in no conscious experience than in conscious experience. During the next 100 ms, however, the outward links of the frontal region were higher in the conscious experience than the no conscious experience at low frequencies. Changes with causal connectivity over time after TMS indicate that the spatial roles in brain regions associated with consciousness are different. These findings may help clarify the cortical mechanisms related to conscious experience.}, year = {2019}, pages = {2133-2138} } @article{MTMT:30792129, title = {NREM sleep in the rodent neocortex and hippocampus reflects excitable dynamics}, url = {https://m2.mtmt.hu/api/publication/30792129}, author = {Levenstein, Daniel and Buzsaki, Gyorgy and Rinzel, John}, doi = {10.1038/s41467-019-10327-5}, journal-iso = {NAT COMMUN}, journal = {NATURE COMMUNICATIONS}, volume = {10}, unique-id = {30792129}, issn = {2041-1723}, abstract = {During non-rapid eye movement (NREM) sleep, neuronal populations in the mammalian forebrain alternate between periods of spiking and inactivity. Termed the slow oscillation in the neocortex and sharp wave-ripples in the hippocampus, these alternations are often considered separately but are both crucial for NREM functions. By directly comparing experimental observations of naturally-sleeping rats with a mean field model of an adapting, recurrent neuronal population, we find that the neocortical alternations reflect a dynamical regime in which a stable active state is interrupted by transient inactive states (slow waves) while the hippocampal alternations reflect a stable inactive state interrupted by transient active states (sharp waves). We propose that during NREM sleep in the rodent, hippocampal and neocortical populations are excitable: each in a stable state from which internal fluctuations or external perturbation can evoke the stereotyped population events that mediate NREM functions.}, year = {2019}, eissn = {2041-1723} } @article{MTMT:30651460, title = {Inhibition and oscillations in the human brain tissue in vitro}, url = {https://m2.mtmt.hu/api/publication/30651460}, author = {Menendez de la Prida, Liset and Huberfeld, Gilles}, doi = {10.1016/j.nbd.2019.02.006}, journal-iso = {NEUROBIOL DIS}, journal = {NEUROBIOLOGY OF DISEASE}, volume = {125}, unique-id = {30651460}, issn = {0969-9961}, abstract = {Oscillations represent basic operational modes of the human brain. They reflect local field potential activity generated by the laminar arrangement of cell-type specific microcircuits interacting brain-wide under the influence of neuromodulators, endogenous processes and cognitive demands. Under neuropathological conditions, the spatiotemporal structure of physiological brain oscillations is disrupted as recorded by electroencephalography and event-relate potentials. Such rhythmopathies can be used to track microcircuit alterations leading not only to transient pathological activities such as interictal discharges and seizures but also to a range of cognitive co-morbidities. Here we review how basic oscillatory modes induced in human brain slices prepared after surgical treatment can help us to understand basic aspects of brain function and dysfunction. We propose to overcome the traditional view of examining human brain slices merely as generators of epileptiform activities and to integrate them in a more physiologically-oriented oscillatory framework to better understand mechanisms of the diseased human brain.}, keywords = {GAMMA; GABA; Theta; Ripples; interictal; human brain slices}, year = {2019}, eissn = {1095-953X}, pages = {198-210}, orcid-numbers = {Menendez de la Prida, Liset/0000-0002-0160-6472; Huberfeld, Gilles/0000-0001-8120-0300} } @article{MTMT:31004918, title = {Perirhinal circuits for memory processing}, url = {https://m2.mtmt.hu/api/publication/31004918}, author = {Miyashita, Yasushi}, doi = {10.1038/s41583-019-0213-6}, journal-iso = {NAT REV NEUROSCI}, journal = {NATURE REVIEWS NEUROSCIENCE}, volume = {20}, unique-id = {31004918}, issn = {1471-003X}, abstract = {The perirhinal cortex (PRC) serves as the gateway to the hippocampus for episodic memory formation and plays a part in retrieval through its backward connectivity to various neocortical areas. First, I present the evidence suggesting that PRC neurons encode both experientially acquired object features and their associative relations. Recent studies have revealed circuit mechanisms in the PRC for the retrieval of cue-associated information, and have demonstrated that, in monkeys, PRC neuron-encoded information can be behaviourally read out. These studies, among others, support the theory that the PRC converts visual representations of an object into those of its associated features and initiates backward-propagating, interareal signalling for retrieval of nested associations of object features that, combined, extensionally represent the object meaning. I propose that the PRC works as the ventromedial hub of a 'two-hub model' at an apex of the hierarchy of a distributed memory network and integrates signals encoded in other downstream cortical areas that support diverse aspects of knowledge about an object.}, year = {2019}, eissn = {1471-0048}, pages = {577-592}, orcid-numbers = {Miyashita, Yasushi/0000-0003-3496-8637} } @article{MTMT:30901031, title = {Mental sleep activity and disturbing dreams in the lifespan}, url = {https://m2.mtmt.hu/api/publication/30901031}, author = {Scarpelli, S. and Bartolacci, C. and D’Atri, A. and Gorgoni, M. and De, Gennaro L.}, doi = {10.3390/ijerph16193658}, journal-iso = {INT J ENV RES PUB HE}, journal = {INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH}, volume = {16}, unique-id = {30901031}, issn = {1661-7827}, year = {2019}, eissn = {1660-4601} } @article{MTMT:30749267, title = {Cortical layers, rhythms and BOLD signals}, url = {https://m2.mtmt.hu/api/publication/30749267}, author = {Scheeringa, Rene and Fries, Pascal}, doi = {10.1016/j.neuroimage.2017.11.002}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {197}, unique-id = {30749267}, issn = {1053-8119}, abstract = {This review investigates how laminar fMRI can complement insights into brain function derived from the study of rhythmic neuronal synchronization. Neuronal synchronization in various frequency bands plays an important role in neuronal communication between brain areas, and it does so on the backbone of layer-specific interareal anatomical projections. Feedforward projections originate predominantly in supragranular cortical layers and terminate in layer 4, and this pattern is reflected in inter-laminar and interareal directed gamma-band influences. Thus, gamma-band synchronization likely subserves feedforward signaling. By contrast, anatomical feedback projections originate predominantly in infragranular layers and terminate outside layer 4, and this pattern is reflected in inter-laminar and interareal directed alpha- and/or beta-band influences. Thus, alpha- beta band synchronization likely subserves feedback signaling. Furthermore, these rhythms explain part of the BOLD signal, with independent contributions of alpha- beta and gamma. These findings suggest that laminar fMRI can provide us with a potentially useful method to test some of the predictions derived from the study of neuronal synchronization. We review central findings regarding the role of layer-specific neuronal synchronization for brain function, and regarding the link between neuronal synchronization and the BOLD signal. We discuss the role that laminar fMRI could play by comparing it to invasive and non-invasive electrophysiological recordings. Compared to direct electrophysiological recordings, this method provides a metric of neuronal activity that is slow and indirect, but that is uniquely non-invasive and layer-specific with potentially whole brain coverage.}, year = {2019}, eissn = {1095-9572}, pages = {689-698}, orcid-numbers = {Fries, Pascal/0000-0002-4270-1468} } @article{MTMT:31004916, title = {Sleep-Wake Cycle in Young and Older Mice}, url = {https://m2.mtmt.hu/api/publication/31004916}, author = {Soltani, Sara and Chauvette, Sylvain and Bukhtiyarova, Olga and Lina, Jean-Marc and Dube, Jonathan and Seigneur, Josee and Carrier, Julie and Timofeev, Igor}, doi = {10.3389/fnsys.2019.00051}, journal-iso = {FRONT SYST NEUROSCI}, journal = {FRONTIERS IN SYSTEMS NEUROSCIENCE}, volume = {13}, unique-id = {31004916}, abstract = {Sleep plays a key role in multiple cognitive functions and sleep pattern changes with aging. Human studies revealed that aging decreases sleep efficiency and reduces the total sleep time, the time spent in slow-wave sleep (SWS), and the delta power (1-4 Hz) during sleep; however, some studies of sleep and aging in mice reported opposing results. The aim of our work is to estimate how features of sleep-wake state in mice during aging could correspond to age-dependent changes observed in human. In this study, we investigated the sleep/wake cycle in young (3 months old) and older (12 months old) C57BL/6 mice using local-field potentials (LFPs). We found that older adult mice sleep more than young ones but only during the dark phase of sleep-wake cycle. Sleep fragmentation and sleep during the active phase (dark phase of cycle), homologous to naps, were higher in older mice. Older mice show a higher delta power in frontal cortex, which was accompanied with similar trend for age differences in slow wave density. We also investigated regional specificity of sleep-wake electrographic activities and found that globally posterior regions of the cortex show more rapid eye movement (REM) sleep whereas somatosensory cortex displays more often SWS patterns. Our results indicate that the effects of aging on the sleep-wake activities in mice occur mainly during the dark phase and the electrode location strongly influence the state detection. Despite some differences in sleep-wake cycle during aging between human and mice, some features of mice sleep share similarity with human sleep during aging.}, keywords = {REM; WAKE; delta power; Sleep-wake cycle; LFP; Sleep fragmentation; SWS}, year = {2019}, eissn = {1662-5137}, orcid-numbers = {Carrier, Julie/0000-0001-5311-2370; Timofeev, Igor/0000-0002-1389-5857} } @{MTMT:30757908, title = {Neuronal Activity During the Sleep-Wake Cycle}, url = {https://m2.mtmt.hu/api/publication/30757908}, author = {Timofeev, I. and Chauvette, S.}, booktitle = {Handbook of Sleep Research}, doi = {10.1016/B978-0-12-813743-7.00001-3}, volume = {30}, unique-id = {30757908}, keywords = {CORTEX; thalamocortical tract; slow wave sleep; oscillation; EEG; sleep waking cycle; sleep; Electroencephalogram; OSCILLATIONS; nerve cell; Thalamus; Thalamus; SLOW-WAVE SLEEP; WAKE; LFP}, year = {2019}, pages = {3-17} } @article{MTMT:30387651, title = {Promoting subjective preferences in simple economic choices during nap}, url = {https://m2.mtmt.hu/api/publication/30387651}, author = {Ai, Sizhi and Yin, Yunlu and Chen, Yu and Wang, Cong and Sun, Yan and Tang, Xiangdong and Lu, Lin and Zhu, Lusha and Shi, Jie}, doi = {10.7554/eLife.40583}, journal-iso = {ELIFE}, journal = {ELIFE}, volume = {7}, unique-id = {30387651}, issn = {2050-084X}, abstract = {Sleep is known to benefit consolidation of memories, especially those of motivational relevance. Yet, it remains largely unknown the extent to which sleep influences reward-associated behavior, in particular, whether and how sleep modulates reward evaluation that critically underlies value-based decisions. Here, we show that neural processing during sleep can selectively bias preferences in simple economic choices when the sleeper is stimulated by covert, reward-associated cues. Specifically, presenting the spoken name of a familiar, valued snack item during midday nap significantly improves the preference for that item relative to items not externally cued. The cueing-specific preference enhancement is sleep-dependent and can be predicted by cue-induced neurophysiological signals at the subject and item level. Computational modeling further suggests that sleep cueing accelerates evidence accumulation for cued options during the post-sleep choice process in a manner consistent with the preference shift. These findings suggest that neurocognitive processing during sleep contributes to the fine-tuning of subjective preferences in a flexible, selective manner.}, year = {2018}, eissn = {2050-084X}, orcid-numbers = {Zhu, Lusha/0000-0001-8717-6356} } @article{MTMT:27555119, title = {Local and Widespread Slow Waves in Stable NREM Sleep: Evidence for Distinct Regulation Mechanisms}, url = {https://m2.mtmt.hu/api/publication/27555119}, author = {Bernardi, Giulio and Siclari, Francesca and Handjaras, Giacomo and Riedner, Brady A and Tononi, Giulio}, doi = {10.3389/fnhum.2018.00248}, journal-iso = {FRONT HUM NEUROSCI}, journal = {FRONTIERS IN HUMAN NEUROSCIENCE}, volume = {12}, unique-id = {27555119}, issn = {1662-5161}, year = {2018}, eissn = {1662-5161}, orcid-numbers = {Siclari, Francesca/0000-0003-2061-9719} } @article{MTMT:30387653, title = {Standing sentinel during human sleep: Continued evaluation of environmental stimuli in the absence of consciousness}, url = {https://m2.mtmt.hu/api/publication/30387653}, author = {Blume, Christine and del Giudice, Renata and Wislowska, Malgorzata and Heib, Dominik P. J. and Schabus, Manuel}, doi = {10.1016/j.neuroimage.2018.05.056}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {178}, unique-id = {30387653}, issn = {1053-8119}, abstract = {While it is a well-established finding that subjects' own names (SON) and familiar voices are salient during wakefulness, we here investigated processing of environmental stimuli during sleep including deep N3 and REM sleep. Besides the effects of sleep depth we investigated how sleep-specific EEG patterns (i.e. sleep spindles and slow oscillations [SOs]) relate to stimulus processing. Using 256-channel EEG we studied processing of auditory stimuli by means of event-related oscillatory responses (de-/synchronisation, ERD/ERS) and potentials (ERPs) in N - 17 healthy sleepers. We varied stimulus salience by manipulating subjective (SON vs. unfamiliar name) and paralinguistic emotional relevance (familiar vs. unfamiliar voice, FV/UFV). Results reveal that evaluation of voice familiarity continues during all NREM sleep stages and even REM sleep suggesting a 'sentinel processing mode' of the human brain in the absence of wake-like consciousness. Especially UFV stimuli elicit larger responses in a 1-15 Hz range suggesting they continue being salient. Beyond this, we find that sleep spindles and the negative slope of SOs attenuate information processing. However, unlike previously suggested they do not uniformly inhibit information processing, but inhibition seems to be scaled to stimulus salience.}, keywords = {auditory stimulation; sleep; Sleep spindles; slow oscillations; High-density electroencephalography}, year = {2018}, eissn = {1095-9572}, pages = {638-648} } @article{MTMT:27302911, title = {Loss of consciousness is related to hyper-correlated gamma-band activity in anesthetized macaques and sleeping humans}, url = {https://m2.mtmt.hu/api/publication/27302911}, author = {Bola, Michal and Barrett, Adam B and Pigorini, Andrea and Nobili, Lino and Seth, Anil K and Marchewka, Artur}, doi = {10.1016/j.neuroimage.2017.11.030}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {167}, unique-id = {27302911}, issn = {1053-8119}, year = {2018}, eissn = {1095-9572}, pages = {130-142} } @inproceedings{MTMT:31844844, title = {The Neurophysiological Effect of Acoustic Stimulation with Real-time Sleep Spindle Detection}, url = {https://m2.mtmt.hu/api/publication/31844844}, author = {Choi, J. and Han, S. and Won, K. and Jun, S.C.}, booktitle = {40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBC 2018}, doi = {10.1109/EMBC.2018.8512323}, volume = {2018-July}, unique-id = {31844844}, year = {2018}, pages = {470-473} } @article{MTMT:30476748, title = {Large-scale structure and individual fingerprints of locally coupled sleep oscillations}, url = {https://m2.mtmt.hu/api/publication/30476748}, author = {Cox, Roy and Mylonas, Dimitris S. and Manoach, Dara S. and Stickgold, Robert}, doi = {10.1093/sleep/zsy175}, journal-iso = {SLEEP}, journal = {SLEEP}, volume = {41}, unique-id = {30476748}, issn = {0161-8105}, abstract = {Slow oscillations and sleep spindles, the canonical electrophysiological oscillations of nonrapid eye movement sleep, are thought to gate incoming sensory information, underlie processes of sleep-dependent memory consolidation, and are altered in various neuropsychiatric disorders. Accumulating evidence of the predominantly local expression of these individual oscillatory rhythms suggests that their cross-frequency interactions may have a similar local component. However, it is unclear whether locally coordinated sleep oscillations exist across the cortex, and whether and how these dynamics differ between fast and slow spindles, and sleep stages. Moreover, substantial individual variability in the expression of both spindles and slow oscillations raises the possibility that their temporal organization shows similar individual differences. Using two nights of multichannel electroencephalography recordings from 24 healthy individuals, we characterized the topography of slow oscillation-spindle coupling. We found that while slow oscillations are highly restricted in spatial extent, the phase of the local slow oscillation modulates local spindle activity at virtually every cortical site. However, coupling dynamics varied with spindle class, sleep stage, and cortical region. Moreover, the slow oscillation phase at which spindles were maximally expressed differed markedly across individuals while remaining stable across nights. These findings both add an important spatial aspect to our understanding of the temporal coupling of sleep oscillations and demonstrate the heterogeneity of coupling dynamics, which must be taken into account when formulating mechanistic accounts of sleep-related memory processing.}, keywords = {EEG; memory consolidation; Sleep spindles; Individual differences; cross-frequency coupling; slow oscillations}, year = {2018}, eissn = {1550-9109}, orcid-numbers = {Cox, Roy/0000-0002-3667-9049} } @article{MTMT:27335053, title = {A novel, fast and efficient single-sensor automatic sleep-stage classification based on complementary cross-frequency coupling estimates}, url = {https://m2.mtmt.hu/api/publication/27335053}, author = {Dimitriadis, Stavros I and Salis, Christos and Linden, David}, doi = {10.1016/j.clinph.2017.12.039}, journal-iso = {CLIN NEUROPHYSIOL}, journal = {CLINICAL NEUROPHYSIOLOGY}, volume = {129}, unique-id = {27335053}, issn = {1388-2457}, year = {2018}, eissn = {1872-8952}, pages = {815-828} } @article{MTMT:30336543, title = {Theta Bursts Precede, and Spindles Follow, Cortical and Thalamic Downstates in Human NREM Sleep}, url = {https://m2.mtmt.hu/api/publication/30336543}, author = {Gonzalez, Christopher E. and Mak-McCully, Rachel A. and Rosen, Burke Q. and Cash, Sydney S. and Chauvel, Patrick Y. and Bastuji, Helene and Rey, Marc and Halgren, Eric}, doi = {10.1523/JNEUROSCI.0476-18.2018}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {38}, unique-id = {30336543}, issn = {0270-6474}, abstract = {Since their discovery, slow oscillations have been observed to group spindles during non-REM sleep. Previous studies assert that the slow-oscillation downstate (DS) is preceded by slow spindles (10 -12 Hz) and followed by fast spindles (12-16 Hz). Here, using both direct transcortical recordings in patients with intractable epilepsy (n = 10, 8 female), as well as scalp EEG recordings from a healthy cohort (n = 3, 1 female), we find in multiple cortical areas that both slow and fast spindles follow the DS. Although discrete oscillations do precede DSs, they are theta bursts (TBs) centered at 5-8 Hz. TBs were more pronounced for DSs in NREM stage 2 (N2) sleep compared with N3. TB with similar properties occur in the thalamus, but unlike spindles they have no clear temporal relationship with cortical TB. These differences in corticothalamic dynamics, as well as differences between spindles and theta in coupling high-frequency content, are consistent with NREM theta having separate generative mechanisms from spindles. The final inhibitory cycle of the TB coincides with the DS peak, suggesting that in N2, TB may help trigger the DS. Since the transition to N1 is marked by the appearance of theta, and the transition to N2 by the appearance of DS and thus spindles, a role of TB in triggering DS could help explain the sequence of elect rophysiological events characterizing sleep. Finally, the coordinated appearance of spindles and DSs are implicated in memory consolidation processes, and the current findings redefine their temporal coupling with theta during NREM sleep.}, keywords = {sleep; Theta; SPINDLES; corticothalamic; downstates; iEEG}, year = {2018}, eissn = {1529-2401}, pages = {9989-10001} } @article{MTMT:3337070, title = {Heterogeneous origins of human sleep spindles in different cortical layers.}, url = {https://m2.mtmt.hu/api/publication/3337070}, author = {Hagler, DJ and Ulbert, István and Wittner, Lucia and Erőss, Loránd and Madsen, JR and Devinsky, O and Doyle, W and Fabó, Dániel and Cash, SS and Halgren, E}, doi = {10.1523/JNEUROSCI.2241-17.2018}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {38}, unique-id = {3337070}, issn = {0270-6474}, abstract = {Sleep spindles are a cardinal feature in human NREM sleep and may be important for memory consolidation. We studied the intracortical organization of spindles in men and women by recording spontaneous sleep spindles from different cortical layers using linear microelectrode arrays. Two patterns of spindle generation were identified using visual inspection, and confirmed with factor analysis. Spindles (10-16Hz) were largest and most common in upper and middle channels, with limited involvement of deep channels. Many spindles were observed in only upper or only middle channels, but about half occurred in both. In spindles involving both middle and upper channels, the spindle envelope onset in middle channels led upper by approximately 25-50ms on average. The phase relationship between spindle waves in upper and middle channels varied dynamically within spindle epochs, and across individuals. Current source density analysis demonstrated that upper and middle channel spindles were both generated by an excitatory supragranular current sink while an additional deep source was present for middle channel spindles only. Only middle channel spindles were accompanied by deep low (25-50Hz) and high (70-170Hz) gamma activity. These results suggest that upper channel spindles are generated by supragranular pyramids, and middle channel by infragranular. Possibly, middle channel spindles are generated by core thalamocortical afferents, and upper channel by matrix. The concurrence of these patterns could reflect engagement of cortical circuits in the integration of more focal (core) and distributed (matrix) aspects of memory. These results demonstrate that at least two distinct intracortical systems generate human sleep spindles.SIGNIFICANCE STATEMENTBursts of approximately 14Hz oscillations, lasting about a second, have been recognized for over 80 years as cardinal features of mammalian sleep. Recent findings suggest that they play a key role in organizing cortical activity during memory consolidation. We used linear microelectrode arrays to study their intracortical organization in humans. We found that spindles could be divided into two types. One mainly engages upper layers of the cortex, which are considered to be specialized for associative activity. The other engages both upper and middle layers, including those devoted to sensory input. The interaction of these two spindle types may help organize the interaction of sensory and associative aspects of memory consolidation.}, keywords = {MEMORY; CORTEX; human; LAYER; SPINDLE}, year = {2018}, eissn = {1529-2401}, pages = {3013-3025}, orcid-numbers = {Ulbert, István/0000-0001-9941-9159; Wittner, Lucia/0000-0001-6800-0953; Erőss, Loránd/0000-0002-5796-5546; Fabó, Dániel/0000-0001-5141-5351} } @book{MTMT:3421100, title = {Sleep, Epilepsies, and Cognitive Impairment}, url = {https://m2.mtmt.hu/api/publication/3421100}, isbn = {9780128125793}, author = {Halász, Péter and Szűcs, Anna}, doi = {10.1016/C2016-0-03610-0}, publisher = {Academic Press as an imprint of Elsevier}, unique-id = {3421100}, year = {2018}, orcid-numbers = {Szűcs, Anna/0000-0002-9990-5787} } @article{MTMT:3328022, title = {Superficial Slow Rhythms Integrate Cortical Processing in Humans}, url = {https://m2.mtmt.hu/api/publication/3328022}, author = {Halgren, M and Fabó, Dániel and Ulbert, István and Madsen, JR and Erőss, Loránd and Doyle, WK and Devinsky, O and Schomer, D and Cash, SS and Halgren, E}, doi = {10.1038/s41598-018-20662-0}, journal-iso = {SCI REP}, journal = {SCIENTIFIC REPORTS}, volume = {8}, unique-id = {3328022}, issn = {2045-2322}, abstract = {The neocortex is composed of six anatomically and physiologically specialized layers. It has been proposed that integration of activity across cortical areas is mediated anatomically by associative connections terminating in superficial layers, and physiologically by slow cortical rhythms. However, the means through which neocortical anatomy and physiology interact to coordinate neural activity remains obscure. Using laminar microelectrode arrays in 19 human participants, we found that most EEG activity is below 10-Hz (delta/theta) and generated by superficial cortical layers during both wakefulness and sleep. Cortical surface grid, grid-laminar, and dual-laminar recordings demonstrate that these slow rhythms are synchronous within upper layers across broad cortical areas. The phase of this superficial slow activity is reset by infrequent stimuli and coupled to the amplitude of faster oscillations and neuronal firing across all layers. These findings support a primary role of superficial slow rhythms in generating the EEG and integrating cortical activity.}, year = {2018}, eissn = {2045-2322}, orcid-numbers = {Fabó, Dániel/0000-0001-5141-5351; Ulbert, István/0000-0001-9941-9159; Erőss, Loránd/0000-0002-5796-5546} } @article{MTMT:27555118, title = {Prenatal Nicotine Exposure Disrupts Infant Neural Markers of Orienting}, url = {https://m2.mtmt.hu/api/publication/27555118}, author = {King, Erin and Campbell, Alana and Belger, Aysenil and Grewen, Karen}, doi = {10.1093/ntr/ntx177}, journal-iso = {NICOTINE TOB RES}, journal = {NICOTINE AND TOBACCO RESEARCH}, volume = {20}, unique-id = {27555118}, issn = {1462-2203}, year = {2018}, eissn = {1469-994X}, pages = {897-902} } @article{MTMT:27590319, title = {Thalamocortical and intracortical laminar connectivity determines sleep spindle properties}, url = {https://m2.mtmt.hu/api/publication/27590319}, author = {Krishnan, Giri P and Rosen, Burke Q and Chen, Jen-Yung and Muller, Lyle and Sejnowski, Terrence J and Cash, Sydney S and Halgren, Eric and Bazhenov, Maxim}, doi = {10.1371/journal.pcbi.1006171}, journal-iso = {PLOS COMPUT BIOL}, journal = {PLOS COMPUTATIONAL BIOLOGY}, volume = {14}, unique-id = {27590319}, issn = {1553-734X}, year = {2018}, eissn = {1553-7358}, orcid-numbers = {Muller, Lyle/0000-0001-5165-9890} } @article{MTMT:27675643, title = {Slow-wave sleep: From the cell to the clinic}, url = {https://m2.mtmt.hu/api/publication/27675643}, author = {Léger, D and Debellemaniere, E and Rabat, A and Bayon, V and Benchenane, K and Chennaoui, M}, doi = {10.1016/j.smrv.2018.01.008}, journal-iso = {SLEEP MED REV}, journal = {SLEEP MEDICINE REVIEWS}, volume = {41}, unique-id = {27675643}, issn = {1087-0792}, year = {2018}, eissn = {1532-2955}, pages = {113-132} } @article{MTMT:30387652, title = {A transient cortical state with sleep-like sensory responses precedes emergence from general anesthesia in humans}, url = {https://m2.mtmt.hu/api/publication/30387652}, author = {Lewis, Laura D. and Piantoni, Giovanni and Peterfreund, Robert A. and Eskandar, Emad N. and Harrell, Priscilla Grace and Akeju, Oluwaseun and Aglio, Linda S. and Cash, Sydney S. and Brown, Emery N. and Mukamel, Eran A. and Purdon, Patrick L.}, doi = {10.7554/eLife.33250}, journal-iso = {ELIFE}, journal = {ELIFE}, volume = {7}, unique-id = {30387652}, issn = {2050-084X}, abstract = {During awake consciousness, the brain intrinsically maintains a dynamical state in which it can coordinate complex responses to sensory input. How the brain reaches this state spontaneously is not known. General anesthesia provides a unique opportunity to examine how the human brain recovers its functional capabilities after profound unconsciousness. We used intracranial electrocorticography and scalp EEG in humans to track neural dynamics during emergence from propofol general anesthesia. We identify a distinct transient brain state that occurs immediately prior to recovery of behavioral responsiveness. This state is characterized by large, spatially distributed, slow sensory-evoked potentials that resemble the K-complexes that are hallmarks of stage two sleep. However, the ongoing spontaneous dynamics in this transitional state differ from sleep. These results identify an asymmetry in the neurophysiology of induction and emergence, as the emerging brain can enter a state with a sleep-like sensory blockade before regaining responsivity to arousing stimuli.}, year = {2018}, eissn = {2050-084X} } @article{MTMT:31844845, title = {Olfactory perception in sleep: Characteristics and application in research and clinical practice}, url = {https://m2.mtmt.hu/api/publication/31844845}, author = {NovÁKovÁ, L.M. and BuŠkovÁ, J.}, journal-iso = {PSYCHIATRIE}, journal = {PSYCHIATRIE}, volume = {22}, unique-id = {31844845}, issn = {1211-7579}, year = {2018}, pages = {195-203} } @article{MTMT:27587897, title = {Contribution of systemic vascular effects to fMRI activity in white matter}, url = {https://m2.mtmt.hu/api/publication/27587897}, author = {Ozbay, Pinar S and Chang, Catie and Picchioni, Dante and Mandelkow, Hendrik and Moehlman, Thomas M and Chappel-Farley, Miranda G and van Gelderen, Peter and de Zwart, Jacco A and Duyn, Jeff H}, doi = {10.1016/j.neuroimage.2018.04.045}, journal-iso = {NEUROIMAGE}, journal = {NEUROIMAGE}, volume = {176}, unique-id = {27587897}, issn = {1053-8119}, year = {2018}, eissn = {1095-9572}, pages = {541-549}, orcid-numbers = {Mandelkow, Hendrik/0000-0003-0274-3599} }