Characterizing Sleep: From Neurochemistry To Special Populations

Abstract

Sleep is a necessary function that has specifically been shown to be important for learning and memory. However, we are only beginning to understand the underlying processes regulating sleep. Sleep and wake states appear to be controlled by fast acting neurotransmitters (e.g. GABA and glutamate), and transitions between NREM and REM sleep involve a mutually inhibitory switch between GABAergic neurons. Better understandings of sleep mechanisms allow us to try to explain sleep disturbances in special populations. Individuals with Down syndrome (DS) have many sleep impairments and cognitive deficits. This thesis sought to further characterize sleep in children with DS by examining separate NREM-REM sleep cycles across the night. Children with DS appear to have an increase in REM sleep latency due to an extremely long duration for the first NREM sleep episode. This may indicate impairment in the initial transition from NREM to REM sleep and help explain the lack of sleep benefit for learning after naps observed in children with DS. Overall, further research into this phenomenon and the mechanisms driving sleep transitions is needed to obtain a more complete understanding of sleep across populations.