Effects of sleep deprivation on functional connectivity of olfactory related brain regions

This study investigated the effects of 36 h of acute sleep deprivation on the functional connectivity of olfactory-related brain regions in healthy young males and examined the relationship between these effects, individual alertness, and emotional state. Sixty participants underwent assessments both before and after sleep deprivation, including a psychomotor vigilance task, a sleepiness scale, a mood scale, and resting-state functional magnetic resonance imaging (fMRI). The results demonstrated that sleep deprivation significantly increased reaction times while reducing reaction speed. Participants exhibited increased sleepiness, particularly during rest, along with significant declines in tension and self-esteem. Notably, functional connectivity within olfactory-related brain regions was significantly disrupted, with alterations extending across multiple areas involved in cognition, emotion, and motor coordination. Specifically, the amygdala showed decreased functional connectivity with the inferior and superior cerebellum, pericalcarine cortex, and lingual gyrus, while the hippocampus exhibited decreased functional connectivity with the lingual gyrus, angular gyrus, middle temporal gyrus, and inferior cerebellum. Further correlation analyses revealed a complex interplay between the functional connectivity of these regions and participants' levels of vigilance, sleepiness, and mood. These findings provide new insights into the broader neurophysiological consequences of sleep deprivation on olfactory-related brain function.

The online version contains supplementary material available at 10.1007/s11571-025-10299-x.