<P> Many physiological changes in the body are associated with fear, summarized as the fight - or - flight response . An inborn response for coping with danger, it works by accelerating the breathing rate (hyperventilation), heart rate, vasoconstriction of the peripheral blood vessels leading to blushing and vasodilation of the central vessels (pooling), increasing muscle tension including the muscles attached to each hair follicle to contract and causing "goose bumps", or more clinically, piloerection (making a cold person warmer or a frightened animal look more impressive), sweating, increased blood glucose (hyperglycemia), increased serum calcium, increase in white blood cells called neutrophilic leukocytes, alertness leading to sleep disturbance and "butterflies in the stomach" (dyspepsia). This primitive mechanism may help an organism survive by either running away or fighting the danger . With the series of physiological changes, the consciousness realizes an emotion of fear . </P> <P> People develop specific fears as a result of learning . This has been studied in psychology as fear conditioning, beginning with John B. Watson's Little Albert experiment in 1920, which was inspired after observing a child with an irrational fear of dogs . In this study, an 11 - month - old boy was conditioned to fear a white rat in the laboratory . The fear became generalized to include other white, furry objects, such as a rabbit, dog, and even a ball of cotton . </P> <P> Fear can be learned by experiencing or watching a frightening traumatic accident . For example, if a child falls into a well and struggles to get out, he or she may develop a fear of wells, heights (acrophobia), enclosed spaces (claustrophobia), or water (aquaphobia). There are studies looking at areas of the brain that are affected in relation to fear . When looking at these areas (such as the amygdala), it was proposed that a person learns to fear regardless of whether they themselves have experienced trauma, or if they have observed the fear in others . In a study completed by Andreas Olsson, Katherine I. Nearing and Elizabeth A. Phelps, the amygdala were affected both when subjects observed someone else being submitted to an aversive event, knowing that the same treatment awaited themselves, and when subjects were subsequently placed in a fear - provoking situation . This suggests that fear can develop in both conditions, not just simply from personal history . </P> <P> Fear is affected by cultural and historical context . For example, in the early 20th century, many Americans feared polio, a disease that can lead to paralysis . There are consistent cross-cultural differences in how people respond to fear . Display rules affect how likely people are to show the facial expression of fear and other emotions . </P>

Fear is an example of which type of response to conflict