“Anxiety, of course, differs from fear, being brought on not by immediate stimulus but by our worries or memories about stimuli real or imagined. From a LeDouxian perspective, one can view anxiety as a mismatch in traffic capacity between pathways lying between the amygdala to and the centers of thought, imagination, and planning humans have so recently developed. LeDoux and others have found many more neural pathways running from the amygdala to the cortex than from cortex to amygdala. This may be why our anxieties often control our thoughts, while our thoughts have trouble quelling our anxieties. Our imagination easily amplifies and feeds the fears coming from the amygdala and hippocampus — we readily worry about what might be or what might have been — but we can’t send enough controls back from cortex to amygdala and hippocampus to dampen the resulting anxiety. That’s why we can seldom calm ourselves by telling ourselves to be calm.”
I write on science, nature, and culture for the New York Times, National Geographic Slate, Nature, and other publications; I've also written three books. More on all that is at daviddobbs.net. For blog posts tied closely tied to those interests, see my main working blog, NeuronCulture.