Association between trait emotional awareness and dorsal anterior cingulate activity during emotion is arousal-dependent

The dorsal anterior cingulate cortex (dACC) is commonly thought to subserve primarily cognitive functions, but has been strongly implicated in the allocation of attention to emotional information. In a previous positron emission tomography (PET) study, we observed that women with higher emotional awareness as measured by the Levels of Emotional Awareness Scale (LEAS) showed greater changes in regional cerebral blood flow (rCBF) in dACC induced by emotional films and recall. In the current study, we tested whether these effects were due to the processing of any non-neutral stimulus, or were specific to conditions of high emotional arousal. Our results extend the previous finding by demonstrating a positive correlation between emotional awareness and dACC activity only in the context of viewing highly arousing pictures. No such relationship was observed when comparing pleasant or unpleasant pictures to neutral or to each other. We also observed that the relationship between LEAS and dACC activity was present in both sexes but stronger in women than men. These results reinforce the concept that greater trait awareness of one's own emotional experiences is associated with greater engagement of the dACC during emotional arousal, which we suggest may reflect greater attentional processing of emotional information.