CHANGES IN REM DREAM CONTENT DURING NIGHT - IMPLICATIONS FOR A HYPOTHESIS ABOUT CHANGES IN CEREBRAL DOMINANCE ACROSS REM PERIODS

REM [rapid eye movement] dream content was scored for categories suggesting the predominant influence of the left hemisphere, e.g., good ego functioning, verbalization or the right hemisphere, e.g., music, spatial salience and bizarreness. Data from 5 samples of college men showed consistent evidence of an increase in the prominence of left-, but not right-, related categories from earlier to later REM periods. There was probably an increase in left hemisphere control/dominance across the REM periods during the night. Apparently there was a positive relation between change in percentage of right eye movement (R%) and temporal position of the REM period and change in left-related categories; greater R% was associated with later REM periods and with more prominent left- (but not right-) hemisphere categories. There was a positive relation between the diminution of the ratio of left to right EEG amplitudes (L/R) and temporal position of the REM period and prominence of verbal activity. This relation was attenuated for those subjects showing a preference for left-handedness.