Meta-analytic evidence for downregulation of the amygdala during working memory maintenance

Abstract

The amygdala is a region critically implicated in affective processes. Downregulation of the amygdala is therefore one of the hallmarks of successful emotion regulation. Downregulation is thought to be established through top-down control of the executive control network over the amygdala. Such a reciprocal relationship, however, is not exclusive to cognitive regulation of emotion. It has recently been noted that any cognitively demanding task may downregulate the amygdala, including a standard working memory task. Here, using a coordinate-based meta-analysis based on an activation likelihood estimation (ALE), we examined whether a standard working memory task (i.e., a 2-back task) downregulates the amygdala similarly to a cognitive reappraisal task. Following the PRISMA guidelines, we included a total of 66 studies using a 2-back working memory task and 65 studies using a cognitive reappraisal task. We found that a standard 2-back working memory task indeed systematically downregulates the amygdala, and that deactivated clusters strongly overlap with those observed during a cognitive reappraisal task. This finding has important consequences for the interpretation of the underlying mechanism of the effects of cognitive reappraisal on amygdala activity: downregulation of amygdala during cognitive reappraisal might be due to the cognitively demanding nature of the task and not per se by the act of the reappraisal itself. Moreover, it raises the possibility of applying working memory tasks in a clinical setting as an alternative emotion regulation strategy.