a basic, intense emotion aroused by the detection of imminent threat, involving an immediate alarm reaction that mobilizes the organism by triggering a set of physiological changes. These include rapid heartbeat, redirection of blood flow away from the periphery toward the gut, tensing of the muscles, and a general mobilization of the organism to take action (see fear response; fight-or-flight response). Fear differs from anxiety in that the former is considered an appropriate short-term response to a present, clearly identifiable threat, whereas the latter is a future-oriented, long-term response focused on a diffuse threat. Some theorists characterize this distinction more particularly, proposing that fear is experienced when avoiding or escaping an aversive stimuli and that anxiety is experienced when entering a potentially dangerous situation (e.g., an animal foraging in a field where there might be a predator). Whatever their precise differences in meaning, however, the terms are often used interchangeably in common parlance.