ANXIETY DISORDERS: A REVIEW

Anxiety is accompanied by a characteristic set of behavioural and physiological responses including avoidance, vigilance and arousal, which evolved to protect the individual from danger. In its nonpathological form, anxiety can be divided into two categories: state anxiety, a measure of the immediate, or acute, level of anxiety; and trait anxiety, which reflects the long-term tendency of an individual to show an increased anxiety response. In its pathological form, anxiety can severely interfere with normal life, and has been classified into six disorders described in the Diagnostic and Statistical Manual of the American Psychiatric Association1: generalized anxiety disorder, social phobia, simple phobia, panic disorder, post traumatic stress disorder (PTSD) and Obessivecompulsive stress disorder (OCD). There are various neurotransmitters that are evolved in the neurobiology of anxiety disorders such as GABA, 5-HT, noradrenaline etc. There are various neural circuits involved in anxiety like amygdala, hippocampus, locus cereulus but main region involved is that amygdala.