Why Humans Experience Fear
Researchers have explained how the brain is wired to react when humans are confronted with something terrifying. It is the amygdala that detects danger, and the cerebral cortex, which harnesses reasoning and judgment, that is impaired in people with phobias. The results are a cyclical pattern of reactions that has been essential to mammalian survival for eons. But how does fear actually develop?
A study of Charles Darwin’s behavior revealed that the fear response is a normal occurrence for humans. He would flinch and jump back when he encountered a dangerous situation. The researchers concluded that this reflex is an inherited and ancient trait, unaltered by modern civilization. Moreover, the amygdala’s effects are not limited to fear. The fear response can lead to physical conditions, including sleep disturbance, dyspepsia, and other illnesses.
Why do humans experience fear? Research has shown that the amygdala projects to the lateral hypothalamus. This area is thought to be the source of fear conditioning. Upon exposing the self to a threat, the spinal cord picks up the stimulus. It then sends a signal to the thalamus and cortex. These two brain regions are then involved in a chain reaction to create the physiological responses that are associated with the fear.
The cultural context that surrounds a particular experience affects a person’s fear. For example, in the early twentieth century, fear of polio was common. Because of its potential to paralyze a person, the disease was often linked to other fears. Similarly, the social context in which a person experiences fear can influence the way he or she expresses the emotion. The social context and the rules governing facial expressions affect how fear manifests in the body.