What do brain imaging studies tell us about anxiety disorders?

In-vivo neuroimaging allows the investigation of brain circuits involved in the experience of anxiety and of receptor changes associated with anxiety disorders. This review focuses on studies by research groups who have compa red brain activation maps in different forms of anxiety and on binding stud ies of the benzodiazepine-GABA(A) receptor. Activation studies have reveale d the involvement of many brain areas depending on the condition and the pa radigm. However, the orbitofrontal cortex/anterior insula and the anterior cingulate are implicated in all the studies and may represent the nodal poi nt between somatic and. cognitive symptoms of any form of anxiety. Most stu dies of binding at the benzodiazepine-GABA(A) receptor are not interpretabl e because of substantial methodological problems, however, regional and/or global reductions are the most consistent finding in panic disorder.