The Science of Halloween: Fear
Imagine a gun’s rammed up against your temple, or a spider the size of your fist is crawling up your arm, or you’re lingering in the wings listening to the rumble of a thousand-strong crowd, waiting to hear you speak… We’ve all felt it: your hearts races, your muscles tighten, your breathing quickens, and adrenaline races through you. We call these intense reactions fear, which is basically an autonomic response controlled by the brain, meaning w don’t consciously trigger fear responses like we consciously speak or walk—instead, a stressful stimulus triggers them. Parts of the brain that play central roles in fear include the thalamus and the sensory cortex (dealing with sensory data), the hippocampus (dealing with conscious memories and processing of stimuli), the amygdala (dealing with emotions, threats and memories of past fears), and the hypothalamus (activating the “fight or flight” instinct). To induce “fight or flight,” the hypothalamus activates two systems: the sympathetic nervous system, which uses nerve pathways to initiate reactions like muscle tightening, increased heart rate and adrenaline rushes; and secondly the adrenal-cortical system, which uses the bloodstream to release about 30 different hormones. These prepare the body for sustained, vigorous action to deal with a threat, by either fighting or fleeing. Humans actually seem to be predisposed to fear certain dangers, thanks to ancient evolutionary instinct—because by fearing the right things, we survive.