Laterality of motor activity during normal and disturbed sleep

Abstract

In a review, Gardner and Grossman (1976) discussed the possibility that small and large sleep movements may be of different neural origin. Small, usually distal, twitches are possibly due to bursts of spinal disinhibition, whereas large movements are mort. likely caused or timed by afferent stimuli. Jovanovic (1971 ) found that daring sleep the nondominant hand is moved twice as much as the dominant, independent of the REM/NREM cycle. Nondominant hand mevements while awake have been shown to reflect higher cerebral functions, spatial rather than verbal problem solving (Hampson and Kimura 1984), and possibly the personal use of visual imagery in verbal encoding (Sousa-Poza et al 1979). The significance of~Ie iiohdominant activity for the psychophysiology of sleep is unclear becw.u,e the laterality might be due to the preferred right-side sleeping posture. Movemel,~t activity might also consist of typical left hz~nd movemei~t~, thus reflecting no difference in activity between wakefulness and sleep. Many subtle forms of deviant lateralizntion