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Cognitive impairment features in neuropsychiatric conditions and when undiagnosed can have a severe impact on the affected individual's safety and ability to perform daily tasks. Virtual Reality (VR) systems are increasingly being explored for the recognition, diagnosis and treatment of cognitive impairment. In this paper, we describe novel VR-derived measures of cognitive performance and show their correspondence with clinically-validated cognitive performance measures. We use an immersive VR environment called VStore where participants complete a simulated supermarket shopping task. People with psychosis ( k = 26 ) and non-patient controls ( k = 128 ) participated in the study, spanning ages 20–79 years. The individuals were split into two cohorts, a homogeneous non-patient cohort ( k = 99 non-patient participants) and a heterogeneous cohort ( k = 26 patients, k = 29 non-patient participants). Participants' spatio-temporal behaviour in VStore is used to extract four features, namely, route optimality score, proportional distance score, execution error score, and hesitation score using the Traveling Salesman Problem and explore-exploit decision mathematics. These extracted features are mapped to seven validated cognitive performance scores, via linear regression models. The most statistically important feature is found to be the hesitation score. When combined with the remaining extracted features, the multiple linear regression model resulted in statistically significant results with R 2 = 0.369, F-Stat = 7.158, p(F-Stat) = 0.000128. [ABSTRACT FROM AUTHOR]

Psychosis is characterized by an elementary lack of trust in others. Trust is an inherently rewarding aspect of successful social interactions and can be examined using neuroeconomic paradigms. This study was aimed at investigating the underlying neural basis of diminished trust in psychosis. Functional magnetic resonance imaging data were acquired from 20 patients with psychosis and 20 healthy control subjects during two multiple-round trust games; one with a cooperative and the other with a deceptive counterpart. An a priori region of interest analysis of the right caudate nucleus, right temporo-parietal junction and medial prefrontal cortex was performed focusing on the repayment phase of the games. For regions with group differences, correlations were calculated between the haemodynamic signal change, behavioural outcomes and patients’ symptoms. Patients demonstrated reduced levels of baseline trust, indicated by smaller initial investments. For the caudate nucleus, there was a significant game × group interaction, with controls showing stronger activation for the cooperative game than patients, and no differences for the deceptive game. The temporo-parietal junction was significantly more activated in control subjects than in patients during cooperative and deceptive repayments. There were no significant group differences for the medial prefrontal cortex. Patients’ reduced activation within the caudate nucleus correlated negatively with paranoia scores. The temporo-parietal junction signal was positively correlated with positive symptom scores during deceptive repayments. Reduced sensitivity to social reward may explain the basic loss of trust in psychosis, mediated by aberrant activation of the caudate nucleus and the temporo-parietal junction. [ABSTRACT FROM AUTHOR]

Abstract Background A relationship between non-neurological autoimmune (NNAI) disorders and psychosis has been widely reported but not yet subjected to meta-analysis. We conducted the first meta-analysis examining the association between NNAI disorders and psychosis and investigated the effect of 1) temporality (as determined by study design), 2) psychiatric diagnosis, and 3) specific autoimmune disorders. Methods Major databases were searched for articles published until April 2018; 31 studies, comprising data for >25 million individuals, were eligible. Using random-effects models, we examined the overall association between all NNAI disorders and psychosis; rheumatoid arthritis was examined separately given the well-established negative association with psychosis. Stratified analyses investigated the effect of temporality, psychiatric diagnosis, and specific NNAI disorders. Results We observed a positive overall association between NNAI disorders and psychosis (odds ratio [OR] = 1.26; 95% confidence interval [CI], 1.12–1.41) that was consistent across study designs and psychiatric diagnoses; however, considerable heterogeneity was detected (I 2 = 88.08). Patterns varied across individual NNAI disorders; associations were positive for pernicious anemia (OR = 1.91; 95% CI, 1.29–2.84), pemphigoid (OR = 1.90; 95% CI, 1.62–2.24), psoriasis (OR = 1.70; 95% CI, 1.51–1.91), celiac disease (OR = 1.53; 95% CI, 1.12–2.10), and Graves' disease (OR = 1.33; 95% CI, 1.03–1.72) and negative for ankylosing spondylitis (OR = 0.72; 95% CI, 0.54–0.98) and rheumatoid arthritis (OR = 0.65; 95% CI, 0.50–0.84). Conclusions While we observed a positive overall association between NNAI disorders and psychosis, this was not consistent across all NNAI disorders. Specific factors, including distinct inflammatory pathways, genetic influences, autoantibodies targeting brain proteins, and exposure to corticosteroid treatment, may therefore underlie this association. [ABSTRACT FROM AUTHOR]