Memory for emotional words following unilateral temporal lobectomy

We recently reported that patients who had received unilateral temporal lobectomy, including the amygdala and hippocampus, show impaired acquisition in a fear conditioning task (LaBar, LeDoux, Spencer, and Phelps, 1995), indicating a deficit in emotional memory. In the present paper, we examined performance of these patients on two verbal, emotional memory tasks in an effort to determine the extent of this deficit. In Experiment 1, subjects were asked to recall emotional and non-emotional words. In Experiment 2, subjects were asked to recall neutral words which were embedded in emotional and non-emotional sentence contexts. Both temporal lobectomy subjects and normal controls showed enhanced recall for emotional words (Experiment 1) and enhanced recall for neutral words embedded in emotional sentence contexts (Experiment 2). These results suggest that the deficit seen in emotional memory following unilateral temporal lobectomy is not a global deficit and may be limited to specific circumstances where emotion influences memory performance. Several hypotheses concerning the discrepancy between the present studies and the fear conditioning results (LaBar et al., 1995) are discussed.