The neurobiology of body dysmorphic disorder: A systematic review and theoretical model

“Fake it till You Make it”! Contaminating Rubber Hands (“Multisensory Stimulation Therapy”) to Treat Obsessive-Compulsive Disorder

“…Accordingly, OCD patients in the asynchronous condition when asked to focus on the fake hand did so in an intensely focused and inflexible manner, conceivably causing them to ignore the overall conflicting sensory information, i.e., leading to global degradation in multisensory integration and overreliance on the salient visual input. This explanation dovetails with the finding that patients with the etiologically related OCD spectrum (''fronto-stratial'') disorder BDD (Grace et al, 2017) display proprioceptive drift bias towards the fake hand during both synchronous and asynchronous stimulation. Unsurprisingly, patients with BDD, like those with OCD, focus on perceptual details at the cost of global, holistic processing (Deckersbach et al, 2000), fittingly evoked as an explanation for such unusual proprioceptive drift bias in BDD (Kaplan et al, 2014).…”

New perspectives in the treatment of body dysmorphic disorder

“…A separate fMRI study comparing visual processing in anorexia nervosa (AN) and BDD used psychophysiological interaction analyses, which estimate functional connectivity between target brain regions and the rest of the brain, to find that patients with BDD demonstrated uniquely heightened functional connectivity in occipitotemporal networks for LSF (testing the processing of holistic information) facial information 30 . Patients with AN and those with BDD showed similar patterns of higher-order connectivity between the right fusiform face area, the precuneus, and the posterior cingulate cortex; they also showed decreased connectivity of the insula and the central opercular cortex 25 , 30 . The authors support the hypothesis that this may show impaired introspection and also cause patients with BDD and patients with AN to overattribute importance to aberrantly processed visual information 25 , 30 , 31 .…”

“…An emerging body of neuroimaging research has led to the development of a working neurobiological model of BDD pathophysiology, one that involves the large-scale disorganization of neural networks involved in cognitive control and interpretation of visual and emotional information 25 . Functional magnetic resonance imaging (fMRI) studies have shown that patients with BDD demonstrate left-sided hyperactivity in several regions within the lateral-temporal-parietal cortices upon exposure to low spatial frequency (LSF) images (which test the processing capacity of holistic information); in contrast, control subjects showed similar activity within the right hemisphere upon exposure to LSF images and showed left-sided activity only in processing of high spatial frequency (HSF) images (which test the processing of detailed featural information) 26 , 27 .…”

“…This result suggests that patients with BDD will interpret even solely holistic visual information via pathways that interpret detailed, focused information. Functional network pathway analysis studies have also found that patients with BDD demonstrated hypoactive structural connectivity and poor transfer of information between primary and secondary occipital regions 25 , 28 . This may be the cause of the relative hypoactivation of the lingual gyrus, parahippocampal gyrus, and the precuneus in the aforementioned fMRI studies 29 .…”

Cortical networks for speech motor control in unilateral vocal fold paralysis

“…We have recently demonstrated that a pitch perturbation task can be used to probe not only vocal motor control but also to examine medial prefrontal cortex activity in relationship to categorization of written words as originating from self versus non‐self . In the context of voice quality as a form of body image perception, non–self categorization of voice productions by treated UVFP patients may be analogous judgment differences of perceived appearance flaws between clinicians and patients in body dysmorphic disorder …”