A systematic review of neurocognition and social cognition in body dysmorphic disorder.

Objective: Neurocognitive underpinnings are implicated in the aetiology and maintenance of body dysmorphic disorder (BDD); however, inconsistent findings across a range of neurocognitive domains suggest that a comprehensive synthesis of the literature using a hierarchical framework of neurocognition is needed.

Methods: A final search across OVID Medline, PsycNET, Scopus and Web of Science databases was conducted on 20 June 2024 to identify research that examined performance on behavioural tasks of objective neurocognition in BDD. Risk of bias was assessed using the Newcastle-Ottawa Scale. Fifty-four studies aligned with the following inclusion criteria: (1) full-text; (2) peer-reviewed; (3) published in English; (4) employed a neurocognitive task with an objective outcome and (5) involved a case-controlled paradigm consisting of BDD and healthy control samples. Findings were synthesised according to neurocognitive sub-domains viewed as a hierarchy from basic to higher-level domains.

Results: Neurocognitive differences in BDD relative to controls were identified at almost all levels of the hierarchy, most consistently in the upper domains of executive function and social cognition. Vulnerabilities were also demonstrated in the sub-domains of visual perception of faces, Gestalt processing, selective attention to faces and verbal memory. Methodological limitations or the influence of neurocognitive sub-groups may contribute to inconsistencies across the literature.

Conclusions: Although neurocognitive differences appear central to BDD, a picture of neurocognitive heterogeneity emerged with the salience of stimuli important and a likely bias to local-over-global processing demonstrated across the domains.