REM Sleep Behavior Disorder Essay -- Neurology Sleeping Papers

Our awareness of the complexity of sleep expanded in 1953 with the discovery of rapid-eye-movement (REM) sleep by Aserinsky and Kleitman. Sleep was no longer considered a homogenous state, but rather a dynamic process of cycling between two distinct states, non-REM and REM sleep. Under normal circumstances the boundaries between non-REM, REM and wakefulness are well declared. Dissociative sleep disorders involve a breakdown of these boundaries (Mahowald and Schenck 1992), and provide a unique window on the neurophysiological mechanisms responsible for each state. Narcolepsy, a disorder of the boundary between wakefulness and REM sleep, is probably the most studied disorder of this nature. The following is a review of another recently described REM sleep boundary disorder called REM sleep behavior disorder (RBD). RBD is characterized by the acting-out of violent dreams during REM sleep, often with injurious consequences (Schenck et al. 1986, 1987). As with narcolepsy, RBD involves a d issociation of REM sleep phenomena and their underlying mechanisms, therefore providing yet another opportunity to broaden our understanding of the complexity of sleep. A brief discussion of REM sleep phenomenology is required before proceeding. REM sleep is characterized by specific phenomena that distinguish it from non-REM sleep and wakefulness (Siegel 1994). These phenomena are grouped according to whether their occurrence is tonic (occurring throughout REM) or phasic (occurring intermittently during REM). Tonic phenomena include, low-voltage desynchronized electroencephalogram (EEG), hippocampal theta rhythm, electromyographic (EMG) atonia, olfactory bulb activity, high arousal threshold, elevated brain temperature, poikilothermia, and penile ... ...REM sleep components in cats: integrity of the pedunculopontine tegmentum (PPT) is important for phasic events but unnecessary for atonia during REM sleep. Brain Res., 571 :50-63. Siegel, J. M. 1994. Brainstem mechanisms generating REM sleep. In: Kryger, M. H., Roth, T. and Dement, W. C. eds. Principles and practice of sleep medicine. 2nd ed. Philadelphia: WB Saunders, pp. 125-144. Sugano, T., Suenaga, K., Endo, S., et al. 1980. Withdrawal delirium in a patient with nitrazepam addictio. Jpn. J: EEG EMG, 8 :34-35. Tachibana, M., Tanaka, K., Hishikawa, Y. and Kaneko, Z. 1975. A sleep study of acute psychotic states due to alcohol and meprobamate addiction. Advances in Sleep Research, 2:177-205. Wright, B. A., Rosen, J. R., Buysse, D. J. et al. 1990. Shy-Drager syndrome presenting as a REM behavioral disorder. J. Geriatric Psychiat. Neurol., 3:110-113.