| Previous research has demonstrated that arousing emotional stimuli are remembered better than neutral stimuli, and that this effect is likely driven by the amygdala and hippocampus. However, whether the emotional modulation of memory is affected by specific genes previously identified as affecting limbic function (e.g., polymorphisms of the serotonin transporter and BDNF genes) is unknown. The current study used fMRI in healthy individuals (n=19; 10 male) to assess BOLD signal during the viewing of positive, negative, and neutral pictures from the International Affective Picture System. A surprise memory test was administered offline one week later. Behavioral results revealed a significant effect of picture type (p<.01), indicating better memory for emotional (positive and negative) than neutral pictures, even when controlling for false alarm rates (d'). Furthermore, participants remembered significantly more negative than positive pictures. fMRI analyses revealed significantly greater activation in the amygdala and hippocampus during the viewing of subsequently remembered emotional versus neutral pictures. Similarly, greater bilateral hippocampal activity occurred when comparing neutral pictures that were subsequently remembered to those that were forgotten. Genetic data are currently being analyzed. These preliminary results support the idea that emotional information is better remembered than neutral information, and that activation of the amygdala and hippocampus during encoding helps to account for this difference. Additional analyses are expected to illuminate the role of genetics in the modulation of emotional memory. |
