Abstracts

Rationale: Although memory, language, and executive functions have been extensively studied in patients with mesial temporal lobe epilepsy (MTLE), few investigations of the decision-making abilities of these patients have been performed. Methods: We studied implicit decision-making (decisions under ambiguity) in right and left MTLE patients (n=20) using the Iowa Gambling Task. The Iowa Gambling Task is believed to detect deficits in decision-making caused by either ventromedial prefrontal cortex or amygdala lesions. Results: In the present study, MTLE patients scored poorly compared to healthy controls on this task, and right MTLE patients exhibited worse performance than left MTLE patients. Conclusions: Our findings indicate that the amygdalo-hippocampal complexes play important roles in decision-making. The right and left amygdalo-hiippocampal complexes may play different roles in implicit decision-making in particular.