The Short Pathway to Fear

Animal brains are amazing, and human brains are no exception. One historically vital and currently nifty feature of our brains is that we can be afraid of something and automatically act in accordance with that fear while consciously asking ourselves, What the fuck am I doing?

The best story I know of along these lines comes from my mom. Several years ago, she was in her bedroom with her sister K, and she pulled a white shirt out of the closet. Then she immediately flung the shirt across the room. Her sister concernedly asked her what was wrong, but she didn't know. Her own behavior was mysterious to her. K walked over to the shirt, looked at it, and declared that there was a spider on the shirt. My mom, who is the most spider-phobic person I know, kind of freaked out all over again because she had absolutely no conscious awareness of there being something on the shirt, let alone a spider. However, her behavior was exactly what she would have done had she known there was a spider - getting the thing the hell away from her. (Ironically, my mom is also actually very brave in that even though she is terrified of spiders, she can make herself hunt them down and kill them because she can't stand knowing that there is a spider in the house.)

The reason my mom flung away the shirt, my cognitive psychology professor stopped in mid-stride with his foot in the air on a hiking path, and Robert launched himself mid-step a couple of feet down the trail in Guadalupe Mountains National Park is that we are blessed with a mental short-cut that allows us to respond to negatively emotionally charged stimuli while by-passing the cortex. Visual information goes to the sensory area of the thalamus, the scary stimuli sparks an alert of "Danger, danger!" (but not a good representation of the object, which occurs in the cortex), and this danger alert is sent directly to the amygdala (the "fear center"), which precipitates an immediate response. Simultaneously, the visual information is being sent along the slow pathway through the cortex, where object recognition occurs, which allows you to eventually realize: Oh, I threw the shirt because there is a spider on it; I stopped mid-stride because there is a copperhead on the trail; I launched myself over this area of the path because there is a snake on it. Snakes and spiders - definitely the type of dangerous stimuli that we would expect our brains to tag as super-important for alerting the amygdala that bad stuff is about to go down, so act now. (It is also unsurprising to me that phobias about snakes and spiders are so common given their importance to our species in the past.)

My own short route to fear is way, way oversensitive, I think. I have sudden freezes with accelerated heart rate all the time, which often end with me looking down and realizing I had been automatically fearful of the raisin that is on the floor. (Hey, it's round and dark colored and on the ground; of course it's going to resemble a spider enough to get things going.) One time I was on my treadmill and suddenly stopped; after stabilizing myself from falling off the treadmill, I realized I must have seen something out of the corner of my eye, so I turned to look at the wall. There was a little spider there. I then thought, jeez, it's just a spider, and got back to my exercise. I am not much afraid of spiders at a conscious level, but spiders still set the short pathway to fear in motion for me as a part of my evolutionary heritage.