Neural correlates of associative memory: the effects of negative emotion

We explored brain activation associated with negative emotionality, during an associative memory task that involved the encoding and retrieval of word pairs. Participants were instructed to memorize word pairs and subsequently retrieve them. The word pairs consisted of either emotional or neutral words. Significant hippocampal activation was observed during both encoding and retrieval of the neutral word pairs, and was correlated with correct response rates during retrieval. However, the negative word pairs activated the left middle temporal gyrus during both encoding and retrieval. These results suggest that hippocampal activation is involved in both the encoding and retrieval of word pairs. However, negative emotionality does not necessarily enhance hippocampal activity and memory performance.