Anxiety disorders fear systems

Anxiety disorders. Disorders that involve sensitivity to physiological changes linked to the sympathetic (fight-or-flight) nervous system and fears related to those changes. 

The NE system is involved in the feeling of energy, fear regulation, general activity, memory and cognition. It is therefore likely that NE is involved in depressive disorder, and in particular in anhedonia, reduced activity and cognition, and in increased anxiety observed in depressed patients. Increased nociception and chronic pain in depression may also be caused, at least in part, by impaired NE transmission (Nutt et al., 2006 Nutt, 2006 Strittmatter et al., 2005). 

The anxiety experienced with this disorder only occurs when the patient must go into feared situations (such as a store) or in the moments before entering the phobic situation (anticipating anxiety). Although such experiences of anxiety ultimately do involve an activation of the limbic system, the primary disorder is felt to be largely psychogenic, a conditioned fear response. Medications are sometimes used to treat agoraphobia without panic however, this disorder is not felt to be biologically based. 

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