Emotional evaluation with and without conscious stimulus identification: evidence from a split-brain patient

Abstract

The present study addresses two main aspects of emotional behaviour. The first concerns the role of conscious identification of the stimulus in producing emotional activity, and the second, a possible hemispheric specialisation for an emotional response. These two issues were addressed by studying the cognitive and physiological emotional activity of a split-brain patient under subliminal and above threshold presentation of emotional and nonemotional stimuli. The results show that the brain has a specific mechanism for distinguishing emotional from neutral situations prior to activating the autonomic nervous system, and that evaluation of the affective significance of the stimuli may occur at different levels not necessarily represented in consciousness. Moreover, the results on the split-brain patient seem to be in accordance with evidence that shows that the relationship between right hemisphere damage and disorders of emotional behaviour lies more at the autonomic arousal level, intimately linked with the experience of emotions, than at the interface between emotional experience and the cognitive or communicative aspects of emotions.