What are you afraid of?

FearLooking into those several week old containers of leftovers in the fridge? Analyzing data for an experiment you’ve now done a third time looking for a tie-breaker? Walking into that small conference room with your thesis committee hoping to graduate? Each of these things can cause the body to enact the fear response.

A great deal of evidence has implicated the portion of the brain called the amygdala in fear and recall of fear and behaviors associated with it. It is incredibly rare for a human to have damage to their entire amygdala but these cases do exist. One example is Patient SM who has a rare condition called Urbach-Wiethe disease. This disease causes a build-up of calcium in blood vessels which can damage particular parts of the brain, in the case of Patient SM, both portions of her amygdala have been destroyed by these calcifications. This woman exhibits no fear response to normally frightening stimuli like snakes, spiders, haunted houses, or scary movies. She cannot recognize fear in the faces of others. She and a few other patients have been critical to studies of how the amygdala modulates fear in humans. Are these people truly fearless? Continue reading “What are you afraid of?”