A Disorder of The Emotional Brain : Neural Correlates of Body Dysmorphic Disorder

Abstract: Body Dysmorphic Disorder (BDD) is a mental disorder where the patient is preoccupied with a misperceived deficit in their appearance. It is a common disorder (~2% prevalence worldwide), leaving the patients significantly disabled and distressed. Comorbid disorders such as social phobia, depression, and anxiety disorders appear frequently. Previous neuroimaging studies have found heterogeneous abnormalities in brain regions involved in visual and emotional processing when comparing BDD patients to healthy controls. Some of these areas are involved in limbic structures. The emotional limbic system (involved in emotion recognition, reward, social behaviour, and decision-making) and the memory hippocampal limbic system (involved in episodic memory, information about objects, faces, and spatial locations) have been stated as two separate neural systems. The aim of this systematic review was to analyse the neural correlates of BDD focusing on structural changes in limbic structures, and further investigate whether the emotional limbic circuit exclusively is affected or solely higher influenced than the rest of the limbic structures. Abnormalities in information processing due to aberrant WM connectivity was found, as well as that volumetric alterations in GM and WM tracts correlate with clinical symptomatology. The relationship between visual and emotional processing system abnormalities and BDD severity suggests an involvement of the emotional limbic system in BDD.