Early and late contingent negative variation (CNV) reflect different aspects of deficits in schizophrenia.

Abnormal reward processing and psychomotor slowing are well-known in schizophrenia (SZ). As a slow frontocentral potential, contingent negative variation (CNV) is associated with anticipatory attention, motivation and motor planning. The present study aims to evaluate the early and late amplitude and latencies of CNV in patients with SZ compared to healthy controls during a reward processing task and to show its association with clinical symptoms. We recruited 21 patients with SZ and 22 healthy controls to compare early and late CNV amplitude and latency values during a Monetary Incentive Delay (MID) Task between groups. Patients' symptom severity, levels of negative symptoms and depressive symptoms were assessed. Clinical features of the patients were further examined for their relation with CNV components. In conclusion, we found decreased early CNV amplitudes in SZ during the reward condition. They also displayed diminished and shortened late CNV responses for incentive cues, specifically at the central location. Furthermore, early CNV amplitudes exhibited a significant correlation with positive symptoms. Both CNV latencies were linked with medication dosage and the behavioural outcomes of the MID task. We revealed that early and late CNV exhibit different functions in neurophysiology and correspond to various facets of the deficits observed in patients. Our findings also emphasized that slow cortical potentials are indicative of deficient motivational processes as well as impaired reaction preparation in SZ. To gain a deeper understanding of the cognitive and motor impairments associated with psychosis, future studies must compare the effects of CNV in the early and late phases.

Fear, Perceived Threat, and Anxiety During COVID-19 Pandemic: The Mediating Role of Cognitive Control/Flexibility and Intolerance of Uncertainty. / COVID-19 Pandemisinde Korku, Algilanan Tehdit ve Kaygi: Bilissel Kontrol/Esneklik ve Belirsizlige Tahammülsüzlügün Aracilik Rolü.

OBJECTIVE: In this study, we aimed to evaluate the relationship between fear of COVID-19, perceived threat of COVID-19, anxiety, cognitive control/flexibility, and intolerance to uncertainty. In addition, the mediating role of cognitive control/flexibility and intolerance to uncertainty were investigated. METHOD: 224 volunteers aged between 18-55 years were included in the study. Cognitive Control and Felxibility Scale, Intolerance of Uncertainty Scale, Fear of COVID-19 Scale, Perceived COVID-19 Threat Form and Beck Anxiety Scales were administered to all participants via an online environment. In this context, Pearson correlation, linear regression, and mediation analyzes were performed. RESULTS: There were significant relationships among Cognitive Control and Flexibility, Intolerance of Uncertainty, Beck Anxiety, fear of COVID-19, perceived COVID-19 threat (p<0,01). Linear regression analysis showed that the Beck Anxiety Scale, Intolerance of Uncertainty and Cognitive Control/ Flexibility Scale scores significantly predicted fear of COVID-19 and the perceived threat of COVID-19 (p<0,001). In addition, mediation analysis revealed that intolerance to uncertainty and cognitive control/flexibility are mediating factors between anxiety and the perceived threat of COVID-19 (p<0,01). CONCLUSION: There is a relationship between fear of COVID-19 and perception of threat, anxiety, intolerance of uncertainty, and cognitive control mechanisms. In accordance with these findings, psychosocial support and therapy programs can be created based on cognitive control/flexibility and intolerance of uncertainty in order to increase the mental health well-being of individuals.

Reduced Reward Processing in Schizophrenia: A Comprehensive EEG Event-Related Oscillation Study.

It is well known that abnormal reward processing is a characteristic feature of various psychopathologies including schizophrenia (SZ). Reduced reward anticipation has been suggested as a core symptom of SZ. The present study aims to evaluate the event-related oscillations (EROs) delta, theta, alpha, beta, and gamma in patients with SZ during the Monetary Incentive Delay (MID) task, which elicits the neural activity of reward processing. Twenty-one patients with SZ and twenty-two demographically matched healthy controls were included in the study. EROs were compared between groups and correlation analyses were conducted to determine a possible relationship between clinical scores and ERO values. Compared with healthy controls, the SZ group had reduced (1) delta and theta amplitudes in the reward condition (2) total beta and non-incentive cue-related beta amplitudes, and (3) incentive cue-related frontal gamma amplitudes. These reductions can be interpreted as impaired dopaminergic neurotransmission and disrupted cognitive functioning in the reward processing of SZ. In contrast, SZ patients showed higher incentive cue-related theta and occipital gamma amplitudes compared to controls. These increments may reflect negative symptoms in SZ. Moreover, theta amplitudes showed a negative correlation with Calgary Depression Scale for Schizophrenia scores and a positive correlation with attentional impulsivity. This is the first study showing the impairments of SZ patients in EROs from delta to gamma frequency bands compared with healthy controls during reward anticipation. Being the first comprehensive study, our results can be interpreted as providing evidence for disrupted brain dynamics in the reward processing of SZ studied by EROs. It may become possible to help patients' wellness by improving our understanding of reward processing in schizophrenia and developing innovative rehabilitation treatments based on these findings.

Enhanced Punishment Responses in Patients With Schizophrenia: An Event-Related Potential Study.

It is well known that abnormal reward processing is a characteristic feature of various psychopathologies including schizophrenia. Reduced reward anticipation has been suggested as a core symptom of schizophrenia. The Monetary Incentive Delay Task (MID) is frequently used to detect reward anticipation. The present study aims to evaluate the amplitude and latency of event-related potential (ERP) P300 in patients with schizophrenia (SCH) compared to healthy controls during the MID task. Twenty patients with SCH and 21 demographically matched healthy controls (HC) were included in the study. ERP P300 amplitude and latency values were compared between groups using an MID task in which reward and loss cues were presented. Relations between P300 and clinical facets were investigated in the patient group. SCH group had enhanced mean P300 amplitudes and delayed peak latency in the punishment condition compared with HC. These higher responses were also associated with negative symptoms. SCH group showed altered reward processing as being more sensitive to loss of reward conditions as firstly evidenced by electrophysiological methods, possibly due to abnormality in various systems including social withdrawal, social defeat, and behavioral inhibition system.

Clinical and developmental characteristics of cognitive subgroups in a transdiagnostic sample of schizophrenia spectrum disorders and bipolar disorder.

Evidence suggests that neurocognitive dysfunction is a transdiagnostic feature of individuals across the continuum between schizophrenia and bipolar disorder. However, there is significant heterogeneity of neuropsychological and social-cognitive abilities in schizophrenia, schizoaffective disorder, and bipolar disorder. The current study aimed to investigate the clinical and developmental characteristics of cognitive subgroups within the schizo-bipolar spectrum. 147 clinically stable patients with schizophrenia, schizoaffective or bipolar disorder were assessed using clinical rating scales for current psychotic and affective symptoms, and a comprehensive neuropsychological battery including measures of social cognition (Hinting and Reading the mind from the Eyes (RMET) task)). Developmental history and premorbid academic functioning were also evaluated. The study also included 36 healthy controls. Neurocognitive subgroups were investigated using latent class analysis (LCA). The optimal number of clusters was determined based on the Bayesian information criterion. A logistic regression analysis was conducted to investigate the predictors of membership to the globally impaired subgroup. LCA revealed two neurocognitive clusters including globally impaired (n = 89, 60.5%) and near-normal cognitive functioning (n = 58, 39.5%) subgroups. The near-normal cognitive functioning subgroup was not significantly different from healthy controls. The globally impaired subgroup had a higher score of developmental abnormalities (p<0.001), poorer premorbid academic functioning, mothers who were less educated and more severe disorganized speech (p = 0.001) and negative symptoms (p = 0.004) compared to the near-normal cognitive functioning group. History of developmental abnormalities and persistent disorganization rather than diagnosis are significant predictors of the subgroup of individuals with global cognitive impairment in the schizophrenia-bipolar disorder continuum.

Association of Wider Social Environment with Relapse in Schizophrenia: Registry Based Six-Year Follow-Up Study.

INTRODUCTON: The impact of social environment on the frequency and prevalence of schizophrenia is well known. However, in schizophrenia and other psychotic disorders, there are few studies which investigate the effect of social environment on disease prognosis and relapse. The aim of this study was to investigate the effect of neighborhood social capital level and address change on relapse in schizophrenia and similar psychotic disorders. METHODS: The research sample consisted of 147 patients (schizophrenia, 76.1%; n=112), who were being followed up at regular intervals of at most six months at the Psychotic Disorders Unit outpatient clinic. Patients were followed-up for relapse indicators between January 1, 2009 and December 31, 2013. During the follow-up, relapse criteria including hospitalization, increased need for help, self-harm, suicidal thoughts, violent behavior, suicide attempts, antipsychotic dose increase and electroconvulsive therapy were used. At least one of these criteria was accepted as a relapse for that period. Neighborhood social capital levels were obtained from a general public survey conducted in Izmir city center in 2008 and the voting rates in the neighborhood during the follow-up period. In addition, during the follow-up period, any change in the address of the patient was recorded. RESULTS: While there was no correlation between the neighborhood social environment and relapse, a significant relationship was found between relapse and address changes. The probability of relapse was 1.3 times higher in patients with change of address (95%CI: 1.0-1.6; p<0.05), and decreased likelihood of relapse was found as the duration of residence in the same neighborhood shortened (ß: (-0.05) 95%CI: [(-0.10)-(-0.003)]; p<0.05). CONCLUSION: In schizophrenia, relapse appears to be related with the narrow social environment (family, home address) in which the person lives, not with the wider social environment (social capital of the neighborhood). The need for adaptation to a new social environment that arises with a change of address, albeit narrowly, can lead to an increase in symptoms of schizophrenia as a psychosocial stressor.

Neurological soft signs in bipolar disorder in comparison to healthy controls and schizophrenia: A meta-analysis.

Neurological soft signs (NSS) are subtle deficits in motor coordination, sensory integration, and sequencing of complex motor acts. Increased NSS is a well-established feature of patients with schizophrenia but a relatively smaller number of studies have investigated NSS in bipolar disorder (BD). Some authors but not others suggested that NSS can distinguish schizophrenia from BD. We conducted a meta-analysis of 18 studies to quantitatively review NSS in BD in comparison to schizophrenia and healthy controls. The current meta-analysis compared NSS scores of 725 BD patients and 634 healthy controls, and 391 BD and 471 schizophrenia patients. Patients with BD had significantly higher NSS scores (d = 1.14, CI = 0.89-1.44) than healthy controls and increased scores in BD was evident in all aspects of NSS (d = 0.88-0.99). BD was associated with a less severe increase in NSS compared to schizophrenia, however, between-group difference was modest (d = 0.42, CI = 0.18-0.65). The results of this meta-analysis demonstrated that BD is characterized by a robust increase in NSS which is only moderately less severe than schizophrenia. Increased NSS is a common feature of both disorders.