| This investigation examined neural mechanisms underlying the expression of lexical (i.e., verbal) motion. Participants included individuals with left-hemisphere (N = 13) and right-hemisphere (N = 13) cortical cerebrovascular lesions, whose lesions were either in anterior or posterior quadrants. Thirteen healthy controls were also included. Participants were asked to produce narratives based on autobiographical memories, which included emotional or nonemotional topics. The narratives were transcribed so that nonverbal factors (i.e., face and prosody) were excluded and raters could focus solely on the lexical emotional content. The dependent variables of emotional content and intensity, positive emotional content and intensity, and negative emotional content and intensity were analyzed in accordance with the right hemisphere and valence hypotheses.; A rating of thematic accuracy was included to assess how accurately the content of the narrative reflected the stimulus cue. The confidence of the raters in making the accuracy decision was also examined. Lastly, the effects of gender on emotion were assessed, as women have been shown to express better language and emotion compared to men.; The data revealed that right-hemisphere lesions did not produce global emotional deficits. Unexpectedly, the left brain-damaged group showed increased difficulties processing emotional and positive emotional content/intensity compared to the right brain-damaged and control groups. This effect was not observed for the negative emotional ratings. The LBD's selective difficulties for positive emotional content and intensity provide some partial support for the valence hypothesis.; These group differences seemed to stem from residual language deficits in the left-hemisphere group. For example, individuals with mild residual aphasic symptoms generally performed more poorly on the experimental tasks than those without language deficits. These findings are discussed in terms of lateralization theory, recovery of emotional function, facilitation effects, and methodological issues.; Other findings included: (1) Anterior compared to posterior damage resulted in reduced emotional output. (2) Negative emotions were rated with more content and higher intensity than positive emotions. (3) Women produced more negative emotional content than men did. |
