Affective verbal memory in patients with temporal lobe epilepsy

Eighteen epileptic patients with unilateral temporal lobe epilepsy (9 left, 9 right) were evaluated with a verbal memory task involving recall of 2 stories, 1 with affective content and 1 that was neutral. A trend for better performance by the group with intact left hemispheres was found for a quantitative score of number of story units recalled. For a qualitative score of number of symbolic distortions, a main effect of affective load was found, such that more distortions were made for the story with affective than neutral content. This effect remained significant when the left temporal lobe epilepsy patients were analyzed separately and was not found for the right temporal lobe epilepsy patients alone. Additional analyses for the subset of 5 patients with left and 6 patients with right temporal lobectomies involving removal of the hippocampus and amygdala were in the same direction as the analyses for all 18 participants. These findings are consistent with other reports of material-specific memory deficits, such that verbal memory deficits are associated with left temporal lobe epilepsy. The differences between performance on the affective and neutral stories for the left and right temporal lobe epilepsy patients are discussed and related to the role of the amygdala in affective processing.