Emotional arousal in temporal lobectomy: autonomic and performance effects of success and failure feedback

Both theory and evidence suggest that right temporal lobectomy (RTL) patients show hypoarousal and left temporal lobectomy (LTL) patients show relative hyperarousal (Davidson, Fedio, Smith, Aurielle, & Martin, 1992). However, we hypothesized that these differences occur only under passive, nonevaluative stimulus conditions. The present study employed, instead, conditions of performance evaluation. We recorded the skin conductance responses (SCRs) and reaction times (RTs) of RTLs, LTLs, and normal controls (NCs) during easy and difficult trial blocks on a target-detection task, with auditory success/failure feedback. We found that LTLs exhibited relative hypoarousal and retarded RTs and that RTLs were normally aroused following success feedback. These results demonstrated that the arousal level of LTLs is contingent on stimulus conditions, thus calling into question the theory that this group is generally subject to hyperarousal. The two-dimensional theory of the neural processing of emotional experience partially explains our data.