A direct amygdala-motor pathway for emotional displays to influence action: A diffusion tensor imaging study

An important evolutionary function of emotions is to prime individuals for action. Although functional neuroimaging has provided evidence for such a relationship, little is known about the anatomical substrates allowing the limbic system to influence cortical motor‐related areas. Using diffusion‐weighted magnetic resonance imaging and probabilistic tractography on a cohort of 40 participants, we provide evidence of a structural connection between the amygdala and motor‐related areas (lateral and medial precentral, motor cingulate and primary motor cortices, and postcentral gyrus) in humans. We then compare this connection with the connections of the amygdala with emotion‐related brain areas (superior temporal sulcus, fusiform gyrus, orbitofrontal cortex, and lateral inferior frontal gyrus) and determine which amygdala nuclei are at the origin of these projections. Beyond the well‐known subcortical influences over automatic and stereotypical emotional behaviors, a direct amygdala‐motor pathway might provide a mechanism by which the amygdala can influence more complex motor behaviors. Hum Brain Mapp 35:5974–5983, 2014. © 2014 Wiley Periodicals, Inc.