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Background: There is accumulating evidence for the role of fronto-striatal and associated circuits in obsessive-compulsive disorder (OCD) but limited and conflicting data on alterations in cortical thickness., Aims: To investigate alterations in cortical thickness and subcortical volume in OCD., Method: In total, 412 patients with OCD and 368 healthy adults underwent magnetic resonance imaging scans. Between-group analysis of covariance of cortical thickness and subcortical volumes was performed and regression analyses undertaken., Results: Significantly decreased cortical thickness was found in the OCD group compared with controls in the superior and inferior frontal, precentral, posterior cingulate, middle temporal, inferior parietal and precuneus gyri. There was also a group × age interaction in the parietal cortex, with increased thinning with age in the OCD group relative to controls., Conclusions: Our findings are partially consistent with earlier work, suggesting that group differences in grey matter volume and cortical thickness could relate to the same underlying pathology of OCD. They partially support a frontostriatal model of OCD, but also suggest that limbic, temporal and parietal regions play a role in the pathophysiology of the disorder. The group × age interaction effects may be the result of altered neuroplasticity., (© The Royal College of Psychiatrists 2017.)

HIV-associated prospective memory (ProM) impairment has emerged, in earlier studies as a significant predictor of medication management and independence in activities of daily living. The relationship between ProM and white matter integrity in HIV has not previously been investigated. Participants, including 128 HIV-infected individuals and 32 healthy controls, were assessed using a comprehensive neuropsychological evaluation and both objective and subjective measures of ProM. Diffusion tensor imaging (DTI) was utilized to investigate the relationship of white matter integrity to ProM in a randomly selected subsample of 40 HIV positive subjects, using a whole brain voxel-based approach to define fractional anisotrophy (FA) and mean diffusion (MD). Total prospective memory was significantly poorer in the HIV positive group when compared with healthy controls (p = 0.023). Time-based ProM was poorer in the HIV group compared to healthy controls both without prompts (p = 0.001) and with prompts (p = 0.001). Poor Total ProM score correlated with performance on neuropsychological tests of executive functioning, information processing speed, learning, and working memory (p < 0.05). Those HIV positive participants with poor ProM had significantly decreased FA in the regions of superior corona radiata (p = 0.0035), the corpus collosum (p = 0.006) and the cingulum (p = 0.0033) when compared to those who were HIV positive with good ProM. This study reinforces the importance of ProM assessment in HIV.