Fear

Fear is a feeling induced by the perceived danger that occurs in certain types of organisms, which causes a change in organ functions and ultimately a change in behavior, such as feeling and hiding. Fear in human beings may occur in response to a specific stimulus occurring in the present of a future threat perceived as a risk to life.

Fear is closely related to but should be distinguished from, the emotion anxiety, which occurs as the result of threats that are perceived to be uncontrolled. The fear response serves survival by generating appropriate behavioral responses. So, it has been preserved throughout evolution.

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