Amygdala Activation in Cognitive Task fMRI Varies with Individual Differences in Cognitive Traits

The amygdala has been implicated in processing threat and learning fear. However, the amygdala also responds to motivationally relevant stimuli even in the absence of explicit emotional content. We investigated the relationship among amygdala activation, cognitive and emotional factors, and fMRI task data in participants from the Young Adult Human Connectome Project. We expected to see variation in amygdala activation that corresponded with variation in traits that could affect the salience of task related stimuli (i.e., internalizing symptoms and fearful faces). We found no relationship between amygdala activation during face viewing and emotion related traits. However, amygdala activation under working memory load was negatively correlated with fluid intelligence and reading level. There also was a negative relationship between task performance and activation in the amygdala. The observed relationship suggests that the role of amygdala is not limited to the processing of emotional content of incoming information but is instead related to salience, which can be influenced by individual differences.