STIMULUS AND SEX-DIFFERENCES IN PERFORMANCE OF MENTAL ROTATION - EVIDENCE FROM EVENT-RELATED POTENTIALS

We examined stimulus and sex differences in reaction time (RT) and eve nt-related potentials (ERPs) during mental rotation of letters and abs tract designs (PMA figures). RTs replicated stimulus and angle effects found in previous studies, but no sex differences were found for eith er set of stimuli. ERP latency data showed women began stimulus evalua tion earlier, and PMA rotations began later over smaller angles, where as letter rotations began later over larger angles. ERP amplitude data replicated hemisphere, electrode, and angle effects found in earlier studies. Amplitude measures also showed greater involvement of anterio r cortical areas for evaluation of letter figures and posterior right temporal lobe for PMA figures, and greater positivity of women's wavef orms than men's over late evaluation and early rotation components. (C ) 1995 Academic Press, Inc.