15 - Role of the cortex in the regulation of anxiety states  pp. 168-179

Role of the cortex in the regulation of anxiety states

By Noelia V. Weisstaub, Caitlin McOmish, James Hanks and Jay A. Gingrich

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Defining fear and anxiety

In evolutionary terms, anxiety is considered to be a conserved behavioral response to a warning signal or a threat (Fuchs & Flugge 2004). This behavior predisposes the individual to recognize potential dangers and to prepare to deal with the threat, allowing the individual to take measures to reduce exposure to danger. In this sense, an anxious state is similar to fear, differentiating itself only in that the latter manifests as an acute response to an immediate threat (Fuchs & Flugge 2004). Both, however, serve the purpose of decreasing an individual's exposure to danger. Thus, under most circumstances, anxiety is an adaptive response to chronic danger and often engages coping mechanisms that help the organism continue with behaviors necessary for survival while minimizing its exposure to danger. This response is generally mild and is associated with recruitment of several physiological systems: motor, sensory, endocrine, immune, cardiovascular, and neuronal.

Pathological anxiety, however, is characterized by a disproportionate response to a mild or non-existent threat (Lesch et al. 2003). In humans, the various anxiety disorders classified by the Diagnostic and Statistical Manual (DSM) all have a common underlying core of pathological processes, including a persistent and increased response to potential threat or a reduced threshold for treating a situation as threatening (Stein & Bienvenu 2004).

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