Historically, sleep has been seen as a passive state, and yet more recent
research demonstrates that sleep is a time for the brain and body to actively fulfill
functions pertaining to cognition, metabolism, and cellular maintenance. Clinical
studies of sleep using polysomnography have demonstrated profound sleep disturbances
in Down syndrome and Alzheimer disease. Deriving from these basic studies is a better
understanding of the networks, neurotransmitters systems, and physiological and
genetic factors that regulate the daily organization of sleep and wake cycles. Currently,
physiological and pharmacological means for manipulating sleep are being developed.
Therefore, it seems plausible that sleep and EEG studies may soon be used to develop
new biomarkers for Down syndrome and Alzheimer’s disease and, in turn, improve
quality of life.
Keywords: Aging, circadian rhythm, cognition, hypocretins, EEG, sleep.
