The amygdala functions in multiple circuits to support diverse psychological abilities. Beyond its role in empathy, the amygdala functions in a circuit encompassing the brain stem, the prefrontal cortex, and the association cortex in the temporal lobe. Heightened responsiveness of this circuit may be associated with general difficulties in the processing of emotional expression and certain peripheral hemodynamic changes in various forms of developmental psychopathology.33–35 Moreover, the amygdala is part of a circuit, encompassing the hypothalamus and periaqueductal gray matter, that mediates graded responses to threats36: from freezing to flight to reactive aggression with increasing proximity of the threat.37 Increased activity in this circuit, after exposure to threat, increases the probability of reactive aggression. Figure 3 depicts the functioning of this circuit, illustrating how threat proximity modulates activity and behavior.
