When the amygdala is repeatedly triggered by chronic stressors, it becomes overactive, and what we see is an exaggerated response to a stimulus like the bear or, as I was beginning to notice in clinic, a nurse with a needle. MRI studies of severely maltreated kids from Romanian orphanages shows dramatic enlargement of their amygdalae. The other thing that happens when the amygdala is chronically or repeatedly activated is that it starts messing up its predictions
