Parietal processing of affect and cognition: cerebral organization in strongly lateralized left-handed subjects

Cerebral organization for the processing of emotion and for the differential processing of affect and cognition have thus far been studied exclusively in right-handed subjects. Since handedness is related to cerebral dominance, our understanding of the neural processing of affect and cognition should be further enhanced by the study of sinistral subjects. The present study examined the differential parietal processing of emotional stimuli under affective and cognitive conditions in left-handed subjects. The subjects were exposed to emotional stimuli presented under affective and cognitive instructional sets and to neutral, control stimuli. Bilateral electroencephalographic and bilateral electrodermal activity data showed greater responsiveness to emotional than neutral stimuli but no differential lateralization of affect and cognition in left-handed subjects. Results also showed that female subjects were more responsive to emotional stimuli than male subjects. Results were interpreted as suggesting that left-handed individuals may be less strongly lateralized for the differential processing of affect and cognition than right-handed individuals and that females may have greater focal organization for the processing of emotion than males.