Oxytocin and social cognition in patients with schizophrenia: comparison with healthy siblings and healthy controls

Objective: There is substantial evidence from animal research indicating a key role of the neuropeptide oxytocin (OT) in the regulation of complex social cognition and behaviour. Social cognition is indispensable for social relationships for the whole of human society, and numerous studies have shown impaired social cognition in schizophrenia (SCH) and unaffected first-degree relatives also seem to be impaired, albeit to a lesser extent. Because of that, this study focuses on the role of OT in social cognition in SCH. Methods: Twenty-seven patients with SCH, 27 healthy siblings (HS) of these patients, and 27 psychologically healthy controls (HC) were included in the study. Blood samples were collected through a peripheral venous catheter. Differences in the socio-demographical and WAIS-R were tested by chi-square and one way-ANOVA. To explore the relationships between social cognition and blood samples we performed Pearson correlations. MANCOVA (gender and WAIS-R as covariates) test was performed to investigate the effect of gender on blood levels of OT and WAIS-R on social cognition. Results: Significant differences were found in neurocognitive and social cognitive capacity but not in OT levels. In the healthy control group, there was a positive correlation between blood OT levels and RMET. There is a statistically significant difference between high and low OT groups with regard to social cognition in all subtests of the RMET. Conclusions: In the current study, we found that patients had deficits in social cognition and neurocognition. Lower endogenous OT levels are also predictive for poor social cognitive functioning in HS and HC

A closer look at the relationship between the subdomains of social functioning, social cognition and symptomatology in clinically stable patients with schizophrenia

Impairments in social functioning commonly seen in schizophrenia are thought to be mediated by deficits in the domains of social cognition. Some previous research has explored how social cognitive skills and psychotic symptoms are associated with social functioning, however these associations are still under debate. The main aim of this study was to investigate the relationship between different domains of social cognition and psychotic symptomatology, and also to look at the relationships with individual subdomains of social functioning within a clinically stable schizophrenia population. 45 outpatients were recruited and symptoms were assessed with the PANSS, and measures of emotion processing, affective and cognitive theory of mind (ToM), mental state reasoning attributional biases, and social functioning were taken. A correlational analysis was performed with the data. Following this, a regression analysis was used to reveal which domains of social cognition best predicted psychotic symptoms. In this stable group of patients, our results support the suggestion of a likely distinction between affective and cognitive components of ToM. The study also demonstrated that ToM and mental state reasoning were the best predictors of psychotic symptoms. Here we reveal that cognitive ToM had the most widespread relationship with social functioning, across multiple subdomains, while only some specific subdomains of social functioning correlated with other domains of social cognition and symptomatology. Further to this, positive symptoms were associated with much fewer subdomains of social functioning than negative and general symptoms. These findings imply that different aspects of social functioning may be served by different domains of social cognition and symptomatology

Towards an integrative approach to understanding quality of life in schizophrenia: the role of neurocognition, social cognition, and psychopathology

The term “schizophrenia” refers to a debilitating group of disorders that usually results in a severely impaired quality of life (QoL). Symptomatology appears to have a substantial role in determining QoL, although the relationship between QoL and specific psychotic symptoms is still unclear and has demonstrated mixed results. Due to the intrinsic importance of social functioning in QoL, and the mediating effect of social cognition on social functioning, the aim of this study was to try to investigate QoL in schizophrenia, not only in terms of symptomatology, but also in consideration of potential neurocognitive and social cognitive contributing factors. Methods: Twenty-eight clinically stable patients with schizophrenia performed a broad range of neurocognitive and social cognitive assessments, and also participated in a semi-structured interview of QoL, assessing four partially independent subdomains of QoL. A stepwise regression model was used to determine the best predictors of QoL, and additionally a mediator analysis was performed to test for the mediating power of social cognition on QoL. Results: Negative symptoms, intelligence, executive functioning and social cognition all had some power in predicting QoL in schizophrenia. Though most interestingly, mental state reasoning was specifically found to be most strongly related with the Intrapsychic Foundation subdomain of QoL, whereas neurocognition and symptom severity were associated with other subdomains of QoL. Conclusions: The association between mental state reasoning and the more “internal” aspects of QoL in schizophrenia may reflect a specific role for social cognition in introspective and subjective judgments of one's own QoL, whereas neurocognition and negative symptomatology may be more predictive of the external or extrinsic aspects of QoL. In conclusion, social cognitive skills appear to play a crucial role in the experience of one's own subjective well-being, which could help to explain previous inconsistencies in the literature investigating QoL in schizophrenia

Social approach and avoidance behaviour for negative emotions is modulated by endogenous oxytocin and paranoia in schizophrenia

Patients with schizophrenia suffer from dysfunctional social behaviour. Social approach and avoidance (AA) has been associated with motor responses,as the affective valence and gaze direction of facial stimuli can bias push and pull motor tendencies. The aim of this study was to investigate the role of endogenous oxytocin in social AA behaviour in schizophrenia. Basal plasma oxytocin levels were collected from 28 patients who were then given a joystick-based Approach Avoidance Task(AAT). Reaction times were recorded and AAT effect scores calculated for responses to happy and angry faces, which either had direct or averted gaze. Individual differences in basal oxytocin had a significant relationship with AAT responses, and patients with higher levels of oxytocin tended to avoid angry faces more. Furthermore, greater avoidance of angry faces was correlated with more severepsychotic (positive and general) symptoms and greater paranoia. This suggests that the endogenous effects of oxytocin may be specific to the interpretation of negative threatening emotions in schizophrenia patients and also provides evidence that psychotic symptoms and paranoia can impact on social AA behaviour by heightening threat avoidance

Oxidative stress in schizophrenia: a case–control study on the effects on social cognition and neurocognition

Background: Schizophrenia is a debilitating mental disorder that presents impairments in neurocognition and social cognition. Several studies have suggested that the etiology of schizophrenia can be partly explained by oxidative stress. However, our knowledge about the implications of oxidative stress on illness-related cognitive deficits is still far from being clear. The aim of this work was to study the role of oxidative stress molecules on social cognition and neurocognition in patients with schizophrenia. Methods: We assessed the peripheral levels of several molecules associated with oxidative stress, namely nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), homocysteine, superoxide dismutase (SOD) and neurotrophin 4/5 (NT4/5), in forty–one patients with schizophrenia and forty-three healthy participants. A battery of tests to measure neurocognition and social cognition was also administered to the schizophrenia group. Results: We found that the schizophrenia group presented substantially higher levels of oxidative stress than the control group, as revealed by elevated quantities of the pro-oxidants NO and MDA, and decreased levels of the antioxidants GSH, SOD and NT4/5. Interestingly, the levels of NT4/5, which have been shown to have antioxidant effects, correlated with executive functioning, as measured by two distinct tests (WCST and TMT). However, social cognition and symptom severity were not found to be associated with oxidative stress. Conclusions: We propose a protective role of NT4/5 against oxidative stress, which appears to have a potentially beneficial impact on neurocognition in schizophrenia

World Federation of Societies of Biological Psychiatry (WFSBP) Guidelines for Biological Treatment of Schizophrenia. Part 3: Update 2015 Management of special circumstances: Depression, Suicidality, substance use disorders and pregnancy and lactation.

Hysteresis loss is an important factor when the performance of superconducting electric power devices is evaluated. The non-ideal voltage–current relation in Bi2Sr2Ca2Cu3Ox/Ag conductors is one of the reasons that critical state based loss relations do not accurately predict the AC loss in these conductors. In this paper the influence of the magnetic field dependent voltage–current relation on the hysteresis loss is discussed. An analytical high-field approach is used to demonstrate the effect of the finite steepness of the voltage–current relation on the induced current. Besides, a numerical technique is used to calculate also for applied magnetic fields below the penetration field the influence of both a field dependent critical current density and a field dependent steepness of the voltage–current relation. Both the magnitude of the hysteresis loss and the field dependence of the loss are influenced by the voltage–current relation. Especially for small applied fields the field dependence of the loss deviates from the cubic dependence that is predicted by the critical state model based relations. Results of calculations are compared with measured data. An intrinsic critical current density vs. magnetic field relation is determined in order to obtain agreement between measurements and calculations