The Thoughts of We

Why Humans Experience Fear is a complex question. Most people suffer from occasional bouts of fear and nervousness, especially before big events. However, in many cases, these feelings are persistent and can interfere with everyday life. What causes fear in humans is not entirely clear. One theory holds that humans have a genetic predisposition to fear certain things. Individuals with first-degree relatives are more likely to develop a specific phobia. Other theories suggest that phobias can result from past or traumatic experiences.

The first theory on why humans experience fear is based on the concept that the human brain has an innate response to danger. The response involves increased heart rate and breathing rate, blood pooling in the peripheral vessels, and muscle tension (the goosebumps sensation). The body also produces increased amounts of white blood cells called neutrophilic leukocytes. Unfortunately, this response may lead to various physical and emotional problems, including disturbed sleep, insomnia, and dyspepsia.

While there is little research available on the brain mechanisms underlying fear, it is believed that fear begins in the amygdala, a part of the temporal lobe, which evaluates the emotional significance of a stimulus. The amygdala releases stress hormones that cause the body to move and produce the characteristic fright response. The amygdala and hippocampus also play important roles in interpreting the perceived threat.