Cognitive and emotional processes were monitored during brain stimulation and with electroencephalographic (EEG) activity from indwelling electrodes in patients with temporal lobe epilepsy (LTE), relating left and right brain dysfunctions to maladaptive ideative and emotional reactions, respectively. Electrical brain stimulation identified a unique group of patients with language functions in the left basolateral temporal lobe, outside the classic brain zones. These patients are anomic interictally and at-risk for postoperative dysphasia. In an EEG study, LTE patients were more strongly aroused by evocative stimuli and had a more negative perceptual bias than right temporal patients. These data underscore the dual cognitive and emotional roles of the limbic system in modulating human behavior.
