Mapping adaptation, deviance detection, and prediction error in auditory processing.

Various studies have suggested that auditory deviance detection is organized in a hierarchical manner with ascending levels of complexity. Event-related potentials (ERP) are considered to reflect different cortical processing stages. In the current electroencephalographic study, we employed an auditory sequence oddball paradigm to investigate different levels of cortical auditory processing and the contribution of neuronal habituation and prediction error mechanism to N1 and Mismatch Negativity (MMN). Our findings suggest that N1 reflects a lower cortical process primarily involved in the encoding of simple physical features and is thus mainly modulated by neuronal attenuation and not complex top-down mechanisms. By analyzing within-sequence signal differences, we divided the MMN into distinct subcomponents reflecting different hierachical levels of auditory processing. We determined a "first-order" MMN that reflects the processing of simple deviant features (such as frequency) and "higher-order" MMNs that occur at regularity violation of complex patterns or unexpected inputs that do not allow further predictions. In our source localization analysis, both the primary auditory cortex and left IFG were primarily involved in the detection of simple, physically deviant features, while the right IFG was associated with the processing of novel, unexpected auditory inputs and the ACC with regularity violation of known patterns. Summarizing, our results might contribute to a better understanding of the different complexities of neuronal habituation and prediction error mechanisms at different levels of cortical auditory processing.

Assessing the relationship between attachment, parental attitude and plasma oxytocin in schizophrenia patients and their unaffected siblings.

BACKGROUND: It is widely acknowledged that schizophrenia patients tend to have insecure attachment styles and improper parenting. However, the biological processes related to these adversities remain unclear and that the disturbance in oxytocin system is considered as one of the strongest predictors of such adversities. METHODS: Thirty-four patients with schizophrenia and their unaffected thirty-four healthy siblings were recruited for the study and they were compared with thirty-one healthy controls. We examined attachment styles via Experience in Close Relationship-Revised Test and perceived parental attitudes with the My Memories of Upbringing-Short Version Test. In addition, we evaluated plasma oxytocin levels across groups. RESULTS: The patients with schizophrenia had lower plasma oxytocin levels and obtained higher levels for attachment anxiety and avoidance with more parental rejection and over protection. There was a significantly negative relationship between the levels of plasma oxytocin in blood and parental over protection in the healthy sibling and healthy control groups. In contrast, there was a significantly positive relationship between the levels of plasma oxytocin in blood and parental over protection in the schizophrenia group. Results of the regression analyses revealed that the plasma oxytocin levels and over protection were notable factors in discriminating the groups from each other. CONCLUSION: Our findings suggested that disturbance in oxytocin is associated with susceptibility to schizophrenia predisposition. In sum, therapeutic interventions that address oxytocin and over protection may influence the outcomes in this severe mental disorder.

The relationship between responsiveness to social and monetary rewards and ADHD symptoms.

Alterations in reward processing are frequently reported in attention deficit hyperactivity disorder (ADHD). One important factor affecting reward processing is the quality of reward as social and monetary rewards are processed by different neural networks. However, the effect of reward type on reward processing in ADHD has not been extensively studied. Hence, in the current study, an exploratory research was conducted to investigate the effect of reward type (i.e., social or monetary) on different phases of reward processing. We recorded event-related potentials (ERPs) during a spatial attention paradigm in which cues heralded availability and type of the upcoming reward and feedbacks informed about the reward earned. Thirty-nine (19 males) healthy individuals (age range: 19-27 years) participated in the study. ADHD symptoms were assessed by using ADHD self-report scale (ASRS). Our results revealed a consistent negative correlation between the hyperactivity subscale of ASRS and almost all social-feedback related ERPs (P2, P3, and FRN). ERP amplitudes after social feedbacks were less positive for P2 and P3 and more negative for FRN for individuals with greater hyperactivity levels. Our findings suggest that hyporesponsiveness to social feedbacks may be associated with hyperactivity. However, the results have to be confirmed with clinical populations.

Symptom Dimensions, Smoking and Impulsiveness in Obsessive-Compulsive Disorder.

BACKGROUND: Obsessive-compulsive disorder (OCD) has distinct symptom dimensions with possibly subtle differences in the underlying neurobiology. One behavioral habit, smoking, has been widely investigated in psychiatric disorders, though received less attention in OCD. Here, we aimed to investigate the relationship between symptom dimensions and smoking behavior in OCD. SUBJECTS AND METHODS: OCD patients (n=167) with the symptom dimensions of washing, taboo thoughts and symmetry-counting-repeating-ordering (S+C+R+O) were questioned in terms of smoking status and assessed with the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Fagerström Test for Nicotine Dependence (FTND), Hamilton Depression Rating Scale-17 Items (HDRS-17), Beck Anxiety Inventory (BAI) and Barratt Impulsiveness Scale-11 (BIS 11). RESULTS: Smoking status differed significantly among patients with distinct symptom dimensions (p=0.009).The ratio of smokers was the lowest in those with the washing (30%, N=12) and the highest in the S+C+R+O (68.2%, N=15) group. Those with taboo thoughts had a smoking ratio of 37.14% (N=39). In post hoc analysis, smoking ratio was significantly higher in the S+C+R+O group than in those with washing symptoms (p=0.004) and taboo thoughts (p=0.007) though it did not differ significantly between washers and taboo thought groups. The BIS-11 did not differ across symptom dimensions. CONCLUSIONS: OCD is a heterogeneous disorder in terms of smoking. Impulsiveness, which does not significantly vary across distinct symptom dimensions, cannot explain this heterogeneity. The severity of addiction does not differ in smokers with OCD across symptom dimensions.

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.

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.

Oxytocin influences avoidant reactions to social threat in adults with borderline personality disorder.

BACKGROUND: Borderline personality disorder (BPD) is characterized by interpersonal dysfunction, emotional instability, impulsivity, and risk-taking behavior. Recent research has focused on the role of oxytocin in BPD, with mixed results as regards the processing of social stimuli. METHODS: In a double-blind randomized placebo-controlled study, 13 BPD patients and 13 controls performed a dot probe task to examine attentional biases to happy and angry faces after intranasal application of oxytocin or placebo. Childhood trauma was examined using the childhood trauma questionnaire. RESULTS: In the placebo condition, patients with BPD (but not controls) showed an avoidant reaction to angry faces (but not happy faces). The strength of the avoidant reaction correlated with the severity of childhood trauma. This behavioral response (as well as the correlation) was abolished in the oxytocin condition. CONCLUSIONS: Adult patients with BPD show an avoidant response to social threat, a reaction that is linked with traumatic experiences during childhood. This response pattern is altered by oxytocin, possibly by reducing stress and inhibiting social withdrawal from distressing social stimuli.

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

UNLABELLED: 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.

Multi-class classification model for psychiatric disorder discrimination.

BACKGROUND: Physicians follow-up a symptom-based approach in the diagnosis of psychiatric diseases. According to this approach, a process based on internationally valid diagnostic tools such as The Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD), patient reports and the observation and experience of the physician is monitored. As in other fields of medicine, the search for biomarkers that can be used in processes related to diseases continues in psychiatry and various researches are carried out in this field. OBJECTIVES: Within the scope of this study, a dataset containing electroencephalogram (EEG) measurements of individuals diagnosed with different psychiatric diseases were analyzed by machine learning methods and the diseases were differentiated/classified with the models obtained. Thus, it was investigated whether EEG data could be a biomarker for psychiatric diseases. MATERIALS AND METHODS: In the dataset analyzed within the scope of the study, for 550 patients (81 bipolar disorder, 95 attention deficit and hyperactivity disorder - ADHD, 67 depression, 34 obsessive compulsive disorder - OCD, 75 opioid, 146 posttraumatic stress disorder - PTSD, 52 schizophrenia) and 84 healthy individuals, there are 634 samples (rows), 77 variables (columns) in total. 76 of the variables consist of absolute power values belonging to 4 frequency bands (alpha, beta, delta, theta) collected from 19 different electrodes. 80 % of the dataset was used for training the models and 20 % of the data was used for testing the performance of the models. The 5-fold cross validation (CV) method, which repeats 3 times in the training dataset, was used and with this method, the hyperparameters used in the models were also optimized. Different models have been established with the selected hyperparameters and the performance of these models has been tested with the test dataset. C5.0, random forest (RF), support vector machine (SVM) and artificial neural networks (ANN) were used to build the models. RESULTS: Within the scope of the study, the absolute power values obtained from EEG measurements performed using 19 electrodes were analyzed by machine learning methods. It was concluded that classification between disease groups was feasible with a high accuracy (C5.0-0.841, SVM_radial - 0.841, RF - 0.762). It was observed that ADHD, depression and schizophrenia diseases can be differentiated better (F-score = 1, balanced accuracy = 1) once the results were evaluated on a class category basis according to the F- measure and balanced accuracy values. DISCUSSION AND CONCLUSION: Through the medium of the analyzes made within the scope of this study, it was investigated whether EEG data could be used as a biomarker for the detection and diagnosis of psychiatric diseases. The findings obtained from this study revealed that by using EEG data as a biomarker, it can be highly predicted whether a person has a psychiatric disease or not. Once evaluated with broad strokes, it is feasible to assert that it is possible to analyze whether the person who consults a physician with a complaint is ranked among the psychiatric disease class with EEG measurement. When trying to differentiate between numerous and diverse disease categories, it may be claimed that some diseases (ADHD, depression, schizophrenia) can be distinguished better by coming to the fore on a model basis. Considering the findings, it is anticipated that the analyzes obtained as a result of this study will contribute to the studies to be conducted using machine learning in the field of psychiatry.

Impact of family involvement on social cognition training in clinically stable outpatients with schizophrenia -- a randomized pilot study.

Recovery of social functioning is a largely unattained goal in schizophrenia rehabilitation. In the recent past, new neurocognitive and social cognitive training approaches have been introduced to improve functioning in various domains of patients' social life. These programs have neglected, to some degree, the social environment in which the training takes place. Accordingly, the present study sought to examine if family-assisted social cognitive training could improve quality of life, social functioning and social cognition in schizophrenia patients as compared to a social stimulation approach. In a randomized, controlled, parallel group trial design with two groups, one receiving family-assisted social cognitive training once a week (F-SCIT) and the other, social stimulation once every three weeks (SS), both for 14-weeks period, patients were assessed at baseline, before randomization and 16weeks after randomization. Participants were recruited from Celal Bayar University Psychosis Unit and were in a clinically stable condition. Patients who received F-SCIT significantly improved in quality of life, social functioning and social cognition, whereas the SS group worsened in nearly all outcome variables. Family-assisted SCIT is effective in improving quality of life, social functioning and social cognition.

Hypnotic ingroup-outgroup suggestion influences economic decision-making in an Ultimatum Game.

Studies in economic decision-making have demonstrated that individuals appreciate social values supporting equity and disapprove unfairness when distributing goods between two or more parties. However, this seems to critically depend on psychological mechanisms partly pertaining to the ingroup-outgroup distinction. Little is known as to what extent economic bargaining can be manipulated by means of psychological interventions such has hypnosis. Here we show that a hypnotic ingroup versus outgroup suggestion impacts the tolerance of unfairness in an Ultimatum Game. Specifically, the ingroup suggestion was associated with significantly greater acceptance rates of unfair offers than the outgroup suggestion, whereas hypnosis alone exerted only small effects on unfairness tolerance. These findings indicate that psychological interventions such as hypnotic suggestion can contribute to ingroup favoritism and outgroup rejection.

[The perceived burden of care and its correlates in schizophrenia]. / Sizofrenide Ailenin Yükünü Etkileyen Etmenler.

OBJECTIVE: The present study aimed to investigate the perceived level of burden of care and its correlates in family members of schizophrenia patients. METHOD: The study included 239 schizophrenic patients that were followed-up at the psychiatric outpatient clinics of Izmir Ataturk Education and Research Hospital, and Celal Bayar University Medical School, and 239 of their primary caregivers. Patients were assessed using the Positive and Negative Syndrome Scale (PANNS), Global Assessment of Functioning Scale (GAF), Social Functioning Scale (SFS), Brief Cognitive State Examination (BCE), and UKU Side Effect Rating Scale. Their primary caregivers were assessed using the Perceived Family Burden Scale (PFBS), Beck Depression Inventory (BDI), and Beck Anxiety Inventory (BAI). RESULTS: Caregiver PFBS scores ere correlated with male patients, female caregivers, inadequate social support, economic difficulty, the presence of chronic physical disorder in the caregivers, patient violence toward the caregivers, total duration of illness, the number of patient hospitalizations, PANNS total and subscale scores, and SFS, BDI, and BAI scores. Perceived burden of care was predicted by the severity of the patients' positive symptoms, SFS independence/competence and interpersonal functioning subscale scores, and caregivers' anxiety and depression levels. CONCLUSION: In order to decrease the burden of care in schizophrenia we recommend effective management of patient symptoms, enhancement of patient social functioning, interventions that target caregivers with high levels anxiety and depression, and social support provided by healthcare professionals.

Prediction of treatment resistance in obsessive compulsive disorder patients based on EEG complexity as a biomarker.

OBJECTIVE: This study aimed to identify an Electroencephalography (EEG) complexity biomarker that could predict treatment resistance in Obsessive compulsive disorder (OCD) patients. Additionally, the statistical differences between EEG complexity values in treatment-resistant and treatment-responsive patients were determined. Moreover, the existence of correlations between EEG complexity and Yale-Brown Obsessive Compulsive Scale (YBOCS) score were evaluated. METHODS: EEG data for 29 treatment-resistant and 28 treatment-responsive OCD patients were retrospectively evaluated. Approximate entropy (ApEn) method was used to extract the EEG complexity from both whole EEG data and filtered EEG data, according to 4 common frequency bands, namely delta, theta, alpha, and beta. The random forests method was used to classify ApEn complexity. RESULTS: ApEn complexity extracted from beta band EEG segments discriminated treatment-responsive and treatment-resistant OCD patients with an accuracy of 89.66% (sensitivity: 89.44%; specificity: 90.64%). Beta band EEG complexity was lower in the treatment-resistant patients and the severity of OCD, as measured by YBOCS score, was inversely correlated with complexity values. CONCLUSIONS: The results indicate that, EEG complexity could be considered a biomarker for predicting treatment response in OCD patients. SIGNIFICANCE: The prediction of treatment response in OCD patients might help clinicians devise and administer individualized treatment plans.

Binomial Logistic Regression and Artificial Neural Network Methods to Classify Opioid-Dependent Subjects and Control Group Using Quantitative EEG Power Measures.

Logistic regression (LR) and artificial neural networks (ANNs) are widely referred approaches in medical data classification studies. LR, a statistical fitting model, is suggested in medical problems because of its well-established methodology and coefficients contributing to the evaluation of clinical interpretations. ANNs are graphical models structured with node networks interconnected with arcs each of which is expressed in terms of weights discovered throughout the modeling process. Since ANNs have a complex structure with its layers and nodes in the layers, which provides ANNs the ability to model any data with complex relationships. Among the various models having origins in statistics and computer science, LR and ANNs have prevailed in the area of mass medical data classification. In this study, we introduce the 2 aforementioned approaches in order to generate a model dichotomizing 75 opioid-dependent patients and 59 control subjects from each other. Quantitative electroencephalography (QEEG) absolute power value of each electrode were calculated for 4 consecutive frequency bands namely delta, theta, alpha, and beta with the frequencies, 0.5 to 4, 4 to 8, 8 to 12, and 12 to 20 Hz, respectively. Significant independent variables contributing to the classification were underlined in LR while a feature selection (FS) method, genetic algorithm, is being applied to the ANN model to reveal more informative features. The performances of the classifiers were finally compared considering overall classification accuracies, area under receiver operating characteristic curve scores, and Gini coefficient. Although ANN-based classifier outperformed compared with LR, both models performed satisfactorily for absolute power measure in beta frequency band. Our results underline the potential benefit of the introduced methodology is promising and is to be treated as a clinical interface in dichotomizing substance use disorders subjects and for other medical data analysis studies.

[The Effect of Theory of Mind Capacities of Mothers of Patients with Schizophrenia on the Severity of the Diseases]. / Sizofreni Hastalarinin Annelerinin Zihin Kurami Kapasitelerinin Hastalik Siddeti Üzerine Etkisinin Incelenmesi.

OBJECTIVE: Studies conducted with patients with schizophrenia and first-degree relatives show that, the pathology in theory of mind may be related to the risk of psychosis. The theory of mind capacities of the mothers may be effective in the prognosis of schizophrenia. The purpose of this study is to examine the effects of theory of mind capacities of patient mothers on the severity of the disease. METHOD: The study was conducted with 34 schizophrenic patients and their mothers, and 31 healthy mothers. Sociodemographic data was captures for all groups. In addition, PANSS was collected from patients and Reading the Mind in the Eyes Test was collected from the each patient mother. RESULTS: There was no statistically significant difference between the age and education levels of the groups. The mothers of patients with schizophrenia performed significantly worse in the Reading the Mind in the Eyes Test than the control group. There was an inverse correlation between theory of mind capacity and the medication dose, PANSS general condition and PANSS total score. DISCUSSION: The significant difference between the groups suggests that the impairment in the function of the theory of mind can be regarded as an endo-phenotype for schizophrenia. The low theory of mind capacities of the mothers of schizophrenia patients can cause the mothers to misunderstand the feelings of their patient which could lead to increase in disease severity and drugs use.

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.

Decreased functional connectivity in schizophrenia: The relationship between social functioning, social cognition and graph theoretical network measures.

Schizophrenia is a complex disorder in which abnormalities in brain connectivity and social functioning play a central role. The aim of this study is to explore small-world network properties, and understand their relationship with social functioning and social cognition in the context of schizophrenia, by testing functional connectivity differences in network properties and its relation to clinical behavioral measures. Resting-state fMRI time series data were acquired from 23 patients diagnosed with schizophrenia and 23 healthy volunteers. The results revealed that patients with schizophrenia show significantly decreased connectivity between a range of brain regions, particularly involving connections among the right orbitofrontal cortex, bilateral putamen and left amygdala. Furthermore, topological properties of functional brain networks in patients with schizophrenia were characterized by reduced path length compared to healthy controls; however, no significant difference was found for clustering coefficient, local efficiency or global efficiency. Additionally, we found that nodal efficiency of the amygdala and the putamen were significantly correlated with the independence-performance subscale of social functioning scale (SFC), and Reading the Mind in the Eyes test; however, the correlations do not survive correction for multiple comparison. The current results help to clarify the relationship between social functioning deficits and topological brain measures in schizophrenia.

Alterations in event-related potential responses to empathy for pain in schizophrenia.

Lack of empathy is a critical factor impacting on social functioning and quality of life in schizophrenia. There is, however, a paucity of research into the underlying neurophysiological correlates of empathy deficits in this disorder. Accordingly, we sought: (1) to identify whether dysfunctional empathic abilities in schizophrenia are related to alterations in early or late brain processes, and (2) to explore the potential relationship between brain activity and mood, self-reported empathy and symptom severity. Eighteen patients with schizophrenia and 21 healthy matched controls performed an empathy-for-pain paradigm where photographs of hands in neutral or painful situations were shown while we recorded their electroencephalography (EEG), and we examined mood, empathic concern for others and symptom severity. Significant group differences between patients and controls emerged in early (50-150ms after stimulus onset) and late (after 300ms) timeframes. Moreover, brain activity was related with unpleasantness ratings in all participants, with self-reported empathic concern only in controls and with negative mood and personal distress only in patients. Differences in social behavior in schizophrenia may be explained by early as well as late differences, affecting mostly the early frontocentral ERPs, i.e. those suggested to correspond to the emotional sharing component of empathy.

Reward modulates the mirror neuron system in schizophrenia: A study into the mu rhythm suppression, empathy, and mental state attribution.

Impairments in the mirror neuron system (MNS) have been implicated as a possible underlying neurological basis for deficits in higher-level social cognition in schizophrenia. Previous work testing this hypothesis has used the electroencephalographic mu rhythm as an index of MNS activity, with studies showing mixed results. Here we investigated the role that reward plays in modulating the mu rhythm, and its association with empathy and emotional mental state reasoning. A group of schizophrenia patients and a healthy control group completed an action observation paradigm in which they watched actions that were financially rewarding, punishing, or neutral. Patients showed intact reward-related modulation of the mu rhythm, and greater mu suppression was associated with greater negative symptoms. There was also a trend for reduced mu suppression in patients. Furthermore, both empathy and emotional mental state reasoning were associated with the degree of mu suppression, but only in healthy controls. These findings confirm the association between the mu suppression and high-level social cognition. It is possible that schizophrenia patients utilize different cognitive routes to infer mental states. The demonstration that reward influences the degree of mu suppression in schizophrenia patients may help to account for previous conflicting findings in the literature.

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 other's 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.