Emotional memory functions of the human amygdala

Affective space is conceptually parsed according to two principal factors or underlying dimensions—arousal and valence. The aforementioned analysis supports a basic dissociation between the amygdala’s contribution to arousal versus valence functions in memory. Whereas the amygdala mediates arousal effects during conditioned emotional learning and across various stages of explicit memory processing (eg, encoding, consolidation, and retrieval), preference formation and affective semantic integration occur outside the amygdaloid system. Unlike its sister structure, the hippocampus, the amygdala’s role inmemory cuts across the implicitexplicit dichotomy. Arousal systems are associated with survival functions, including defensive, reproductive, and maternal behaviors, which may account for the amygdala’s participation in certain emotions over others. The scientific understanding of emotional memory will be further refined with improved neuroscientific methodologies and paradigm development. In particular, future studies should characterize the amygdala’s participation in other forms of implicit memory and clarify the scope of its influence beyond basic emotions such as fear.