Categorical and dimensional decoding of emotional intonations in patients with focal brain lesions

The present study attempts to elucidate whether cerebral brain lesions differentially affect the crossmodal decoding of emotional intonations in semantically meaningless sentences. Forty patients with well-documented lesions and 12 matched hospital controls participated in the study. Twenty-one had left brain damage (LBD: 12 with anterorolandic (anterior) and 9 with retrorolandic-infrasylvian (posterior) lesions); 19 had right brain damage (RBD: 12 anterior, 7 posterior lesions). The decoding of emotion categories was measured using (a) multiple choice of verbal labels and (b) matching one emotional vocalization (joy, fear, sadness, or anger) with two choice facial expressions. Crossmodal dimensional decoding was assessed by matching vocalizations with two facial expressions with regard to emotional valence or arousal. Results indicate that labeling was reduced in all lesion groups as compared to that in controls. Crossmodal categorical recognition was impaired in RBD, whereas LBD performance was comparable to controls. However, in the dimensional decoding task, a reduced recognition of valence in LBD and arousal in RBD was observed. An analysis of localizational subgroups revealed that subjects with left ventral frontal lesions, which in part extended into the adjacent right hemisphere, were predominantly impaired in the crossmodal identification of valence, whereas right temporoparietal lesions affected arousal decoding. Our results suggest that lateralized lesions may differentially affect the crossmodal recognition of dimensional concepts such as valence and arousal.