anxiety, anticipatory tension or vague dread persisting in the absence of a specific threat. In contrast to fear, which is a realistic reaction to actual danger, anxiety is generally related to an unconscious threat. Physiological symptoms of anxiety include increases in pulse rate and blood pressure, accelerated breathing rates, perspiration, muscular tension, dryness of the mouth, and diarrhea. Freud postulated that anxiety was a result of repressed, pent-up sexual energy, but later came to view it as a danger signal alerting the ego to excessive stimulation and causing repression. Anxiety disorders include observable, overt anxiety, as well as phobias and other conditions where a defense mechanism has been set up to disguise the anxiety from both the sufferer and the observer. In generalized anxiety, the individual experiences long-term anxiety with no explanation for its cause; such a condition may be called free-floating, since it is not linked to a specific stimulus. Panic disorder involves sudden anxiety attacks which are manifested in heart palpitations, shortness of breath, or fainting. The individual with a phobic disorder can identify the stimulus that causes anxiety: such stimuli as enclosed space, heights, and crowds become imbued with greatly exaggerated anxiety and are carefully avoided by the phobic individual. Obsessive-compulsive disorders (OCD) are characterized by obsessions (mental quandries) and compulsions (physical actions) that engage the individual excessively. Extreme anxiety may be experienced if the person does not carry out the compulsion or attempts to ignore the obsession. Post-traumatic stress disorder occurs when an individual has recurrent dreams, flashbacks, or panic attacks after a particularly traumatic experience.
See D. F. Klein, Anxiety (1987); D. H. Barlow, Anxiety and Its Disorders (1988); S. J. Rachman, Fear and Courage (1990).