EEG coherence and power spectra during REM sleep related to melatonin intake in mild-to-moderate Alzheimer's disease: a pilot study.

The possibility that the inhibitory GABAergic pathways related to REM sleep generation are well-preserved in mild-to-moderate AD is discussed. We conclude that the short REM sleep onset related to melatonin intake in AD patients is associated with a significant decrease in both RP and EEG coherence, mainly in the fast frequencies.