REM sleep behavior disorder
Even though we may not need REM sleep to function well, REM sleep behavior disorder (RBD) is a sign that our health may be in trouble. In 1986, scientists from the University of Minnesota reported a bizarre REM sleep pathology in four men and one woman who would act out their dreams. One 67-year-old man, for example, reportedly punched and kicked his wife at night for years. One time he found himself kneeling alongside the bed with his arms extended as if he were holding a rifle (he dreamt he was in a shootout). His overall health, however, seemed unaffected apart from self-injury during some episodes.
However, in 1996 the same group of researchers reported that 11 of 29 men originally diagnosed with RBD went on to develop a parkinsonian disorder. Combined data from 24 centers of the International RBD Study Group puts that number as high as 74% at 12-year follow-up. These patients get diagnosed with Parkinson’s disease, dementia with Lewy bodies, or multiple system atrophy. Scientists believe that the protein alpha-synuclein forms toxic clumps in the brain, which are responsible both for malfunctioning of muscle atonia during REM sleep and subsequent neurodegenerative disorders.
While some researchers say that RBD may offer a unique window into better understanding REM sleep, we’re still a long way off from fully figuring out this biological phenomenon. According to Dr. Blumberg, the story of REM sleep has arguably become more muddled in the 7 decades since Dr. Aserinsky and Dr. Kleitman published their original findings, dispelling myths about ‘fatigue toxins’ and sleep as a passive, coma-like state. Dr. Mendelson concurred: “It truly remains a mystery.”
Dr. Blumberg, Dr. Mendelson, and Dr. Siegel reported no relevant disclosures.
A version of this article originally appeared on Medscape.com.