Orkun Aydın

The developmental origins of metacognitive deficits in schizophrenia.

The deficits in metacognition have been observed in schizophrenia but developmental roots of impaired metacognition are not well understood. Accordingly, this study compared metacognitive abilities of patients with schizophrenia and healthy group and examined the relationship between childhood trauma, attachment style and caregiver attitudes with metacognitive capacity which might contribute to metacognitive deficits in patient group. 35 patients with schizophrenia and 35 healthy people were included in the study. Metacognitive capacity was measured using the Metacognition Assessment Scale Abbreviated (MAS-A). This scale comprises four domains: self-reflectivity, understanding others mind, decentration and mastery. Group comparisons revealed that schizophrenia patients had greater deficits in metacognitive ability. We found that the report of childhood emotional abuse, a pattern of anxious attachment and over protection by caregivers were uniquely related to metacognitive capacity.

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

ABSTRACT 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.

Cortisol response to stress in schizophrenia: Associations with oxytocin, social support and social functioning

Previous studies reported attenuated cortisol reactivity as one explanation for poor social functioning in schizophrenia. Recent research has demonstrated that both glucocorticoid and oxytocin systems are central to stress regulation. Here, we studied the associations between basal oxytocin, stress-induced cortisol levels, and social functioning and social support in schizophrenia. A mock job interview was used as an ecologically-valid social stressor in 32 schizophrenia patients. Blood samples were taken before and after stress induction to assess basal oxytocin and cortisol levels. In addition social functioning and social support scales were collected. Patients were divided into cortisol responders and non-responders according to percentage change following stress induction. Our findings revealed a possible subgroup of patients who did not exhibit attenuated cortisol responses. Importantly, cortisol responders had generally better social functioning, but perceived social support was not different between groups. There was also no evidence of a relationship between cortisol and oxytocin. This study highlights the heterogeneity of cortisol responses to stress in a schizophrenia population, and the importance of the relationship between social functioning and cortisol reactivity. These findings could be relevant when considering therapeutic interventions that manipulate endocrinology in order to improve real-world functioning.

The comparison of executive functions, social cognition and plasma oxytocin level between mothers of schizophrenia patients and healthy control: Searching for a new endophenotype

Objective: Previous studies documented that there were a variety of endophenotypes that helped to diagnose as well as to predict functionality and treatment response. There is little, if any research that focused on investigating biochemical endophenotypes. Besides, the studies that include executive functions and social cognition, which were accepted as endophenotypes, have different results. In studies involving schizophrenia patients, the deficiency of oxytocin was found to be the most important hormone that would affect the treatment process. However, there have been no endophenotype studies that investigated the role of oxytocin hormone in the treatment process of schizophrenia patients. The purpose of the present study was twofold: (a) to detect new endophenotypes, and (b) to test endophenotypes that were previously found by focusing on the schizophrenia patients’ mothers. Methods: The participants were the healthy mothers of schizophrenia patients and healthy control group. They took the Reading the Mind in the Eyes Test, Wisconsin Card Sorting Test, and Wechsler Adult Intelligence Scale vocabulary subtest, respectively. In addition, participants’ blood samples were collected to include the level of plasma oxytocin as a biochemical in the data analyses. Results: Results revealed that there was a significant difference in plasma oxytocin levels for the healthy mothers of schizophrenia patients and the healthy control group. Low level of plasma oxytocin level was found to be the only significant factor that differentiates the patients’ mothers and the healthy control group. When the results of the Reading the Mind in the Eyes Test that measures executive functions, and the Wisconsin Card Sorting Test that measures social cognition were analyzed, no significant differences were found between the groups. Discussion: Our findings showed that oxytocin hormone could be a new endophenotype for schizophrenia. However, there is still a need for studies that focus on the investigation of detecting new endophenotypes.