Sleep spindles are developmentally relevant cortical oscillatory patterns; however,
they have mostly been studied by considering the entire spindle frequency range
(11–15 Hz) without a distinction between the functionally and topographically different
slow and fast spindles, using relatively few electrodes and analysing wide age ranges.
Here, we employ high-density night sleep electroencephalography in three
age-groups between 12 and 20 years of age (30 females and 30 males) and analyse
the adolescent developmental pattern of the four major parameters of slow and fast
sleep spindles. Most of our findings corroborate those very few previous studies that
also make a distinction between slow and fast spindles in their developmental analysis.
We find spindle frequency increasing with age. A spindle density change is not
obvious in our study. We confirm the declining tendencies for amplitude and duration,
although within narrower, more specific age-windows than previously determined.
Spindle frequency seems to be higher in females in the oldest age-group.
Based on the pattern of our findings, we suggest that high-density electroencephalography,
specifically targeting slow and fast spindle ranges and relatively narrow
age-ranges would advance the understanding of both adolescent cortical maturation
and development and the functional relevance of sleep spindles in general.
