Narrative speech production (NSP), i.e., the conceptualization, linguistic formulation,
and articulation of a story, is a multifaceted process underpinned by cognitive functions
and mentalization ability, often impaired in individuals with borderline personality
disorder (BPD). This study examines differences in coherence and temporal parameters
between individuals with BPD and healthy controls (HCs) and explores associations
between these factors in both groups. Spontaneous speech of 33 BPD and 31 HC individuals
was recorded in three task types (telling their previous day, retelling a story, picture
sequences), tapping different cognitive functions. Local and global coherence were
extracted with contextual sentence vectors, while temporal parameters were extracted
with automatic speech recognition. A series of linear mixed-effects models revealed
that NSP of individuals with BPD is mainly characterized by significantly lower global
coherence and speech rate and higher number of silent and filled pauses than HCs’.
Global coherence displayed significant between-group differences only in picture tasks
and correlated with picture arrangement. Spearman correlation matrix showed a significant
negative association between global coherence and speech rate within the BPD group
and an opposite tendency among HCs. Findings indicate that individuals with BPD might
benefit from speaking at a slower pace to improve global coherence in their narratives.
