Why Humans Experience Fear
Why do we experience fear? The biological basis for this emotion is unclear, but the underlying mechanisms are well understood. The brain reacts to a terrifying stimulus by triggering a fight or flight response, and this physiological reaction is related to the “face of fear.” When presented with an image of a snake, for example, the amygdala, our sensory centers, fires up. When the brain sees the low road, it sends an alarm signal to the rest of the body: it begins to sweat, and it also triggers the adrenaline response.
The brain sends signals to different parts of the body to activate the fear response. The body responds to these signals by enhancing its blood pressure, increasing heart rate, and sweating. The muscles of the arms, legs, and stomach also feel tense. The brain uses memory-based expectations to create this physical reaction. However, this process can’t be reversed. If the fear is caused by a threatening stimulus, it will not cause a physical response.
The reason that people with phobias don’t experience fear is because the fearful stimulus triggers a physiological reaction in them. These reactions include a heightened heartbeat, rapid breathing, increased blood pressure, and increased sweating. In addition, blood is pumped to muscle groups, increasing the likelihood of physical action. The body will also secrete sweat to keep its temperature up. Besides the effects on the body and the mind, fear can have physiological consequences that are similar to human behavior.