Fear is natural part of human psyche. Everyone has his/her own fears. The behaviour of people around us influences our responses to threatening situations. Often it is hard to forget threats. The emotional impact of fearful event often continues for long. Accidents haunt us for a long time; driving at night seems more dangerous, if the accident had occurred during the night. The fearful memories get easily triggered and are hard to shake off. Fear is a learned activity. Fear conditioning prepares an organism to learn about predicting adverse events. The early humans survived as they were quick to respond to dangerous situations. The obstacles to survival prepared our brain to deal with the threats. Fear is frequently related to escape and avoidance behaviour. When afraid we tend to fight, freeze or flee. Brain researchers say, in less than 100 milliseconds sensory information reaches amygdala and in the split seconds our adrenaline surges, eyes widen, heart rate increases, breathing quickens, stomach wrenches, palms moisten, and time slows down. These are the signs of fear.
One way to reduce the impact of anxiety producing memory is to guide them to form a new memory that extinguishes fearful memory. Take for example, a car accident that occurs at a particular intersection, and at that time a certain song was playing on the radio. For a period, whenever you cross that intersection or hear the song, you will re-experience fear. Slowly this fearful memory will fade, and your fear will extinguish.
The experience of fear follows two paths in the brain. One is conscious and rational (also known as high road), and the other is unconscious and innate (also known as low road). The unconscious path transmits a signal from a stimulus to the thalamus, and then to the amygdala, which then activates a fear-response in the body. The conscious path, the slower road, also includes the cortical parts of the brain, thus creating a conscious impression of what the stimulus is. The low road is regarded as a more primitive mechanism of defence and exists in lesser developed animals. In the more developed animals, both the conscious and unconscious paths work simultaneously to provide both fear-response and perceptual feedback. Say, your eyes and ears detect a snake. It might take a few seconds to establish the presence of the snake and formulate a response via the high road, but the low road kicks the body into a freezing response within a fraction of a second.