Yes, the amygdala was showing an increase in activity, but only in certain situations, like when the eyes of a face were staring directly at the viewer. If the eyes were gazing off to the side, the neurons in the amygdala barely changed their firing rates. Also, if test subjects viewed the same stereotyped fear pose over and over again, their amygdala activation rapidly tapered off. If the amygdala truly housed the circuit for fear, then this habituation should not occur—the circuit should fire in an obligatory way whenever it is presented with a triggering “fear” stimulus. From these contrary
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