Donepezil-induced REM sleep augmentation enhances memory performance in elderly, healthy persons.

Previous research in younger individuals has shown that acetylcholinesterase inhibitors may enhance REM sleep. The present study indicates that in the elderly, donepezil, an acetylcholinesterase inhibitor, also exerts a marked effect on REM sleep parameters--percentage of REM sleep and REM density were increased whereas REM latency was reduced. In addition, we also found a correlation between memory performance and REM sleep. Based on these findings, we conclude that there is an interrelationship between cognitive performance and amount of REM sleep in elderly humans as has been previously shown in animals and young adults.