Chapter 9 - The hypothalamus in anxiety disorders

Abstract

Of all mental disorders, anxiety disorders are currently the strongest contributors to the global burden of disease, with 7.3% of the general population affected worldwide. The hypothalamus is crucial hub of a network of neural structures modulating fear conditioning and extinction and, as such, highly relevant to the pathophysiology of these conditions. Three hypothalamic systems have emerged as particularly relevant in this context. First, the oxytocin system is highly likely to be involved anxiety disorders and in particular in the cognitive and behavioral deficits pertaining to social anxiety disorder. Second, peripheral markers of the hypothalamic-pituitary-adrenal axis appear altered in patients with panic disorder and generalized anxiety disorder, which may denote aberrant functioning of their central corticotropin-releasing hormone system. Furthermore, cortisol seems to augment the effects of exposure therapy in patients with specific phobia. Third, the integrity of the hypothalamic-pituitary-thyroid axis is likely compromised in panic disorder. Further, cross-disciplinary research efforts are required to shed more light on how, exactly, these hypothalamic systems interact with the neural structures involved in fear conditioning and extinction, which should ultimately open up new avenues for the prevention and treatment of anxiety disorders.