Understanding Why Humans Experience Fear
The mechanisms that underlie the experience of fear are multifaceted. Fear is caused by a wide variety of stimuli, ranging from basic unconditioned stimuli to complex symbolic knowledge. It activates core biological responses and can be modulated by the subject. Although the upper left and lower right components of fear are shared across a broad range of species, humans exhibit distinct characteristics. Moreover, fear affects the processing mode of cognition. It interacts with nearly every aspect of the cognitive system.
When the body experiences fear, the sympathetic nervous system is stimulated, triggering the adrenal glands to release hormones that trigger physical reactions. Whether a person experiences fear on a deep or surface level is highly personal. In fact, the biological response to fear involves similar chemical responses to those experienced by positive emotions. For example, someone may love a roller coaster ride while another person may avoid it. This is a result of the fight or flight response.
The fear response is a natural one that helps the person to react to threats. The physiological reactions evoked by fear include sweating, increased heart rate, dilated pupils, and the release of inflammatory chemicals, such as adrenaline. These responses are necessary for the body to prepare for battle or run away from the threat. While the fear response is an instinctive response, it can be a symptom of mental health conditions such as panic disorder or post-traumatic stress disorder.