Bilateral electrodermal activity as a function of hemisphere-specific stimulation, hand preference, sex and familial handedness.

UNLABELLED: The effects of unilateral stimulation on bilaterally recorded electrodermal activity are not well understood. Factors that may contribute to bilateral response differentiation under conditions of unilateral stimulation include preferred hand, sex and familial handedness. To assess the effects of these factors, 64 subjects were each assigned to one of four cells defined by sex and preferred hand. Each subject received a counterbalanced series of 31 slides depicting objects spatially and intended to activate the right hemisphere and 31 slides depicting objects spatially and intended to activate the left hemisphere. Each condition was followed by a blank slide. Results showed smaller mean nonspecific responses on the hand contralateral to the hemisphere for which stimulation was intended. This supports the hypothesis that a contralateral inhibitory process underlies electrodermal responsiveness. Further results showed that the effects of unilateral stimulation on bilaterally differentiated electrodermal activity are mediated by familial handedness and sex. DESCRIPTORS: hemispheric processes, bilateral EDA, sex, familial handedness, preferred hand.