Neurocognition in schizophrenia: from prodrome to multi-episode illness

Comparative analysis of anticholinergic burden scales to explain iatrogenic cognitive impairment in schizophrenia: results from the multicenter FACE-SZ cohort

Aim

The anticholinergic properties of medications are associated with poorer cognitive performance in schizophrenia. Numerous scales have been developed to assess anticholinergic burden and yet, there is no consensus indicating which anticholinergic burden scale is more relevant for patients with schizophrenia. We aimed to identify valid scales for estimating the risk of iatrogenic cognitive impairment in schizophrenia.

Methods

We identified 27 scales in a literature review. The responses to neuropsychological tests of 839 individuals with schizophrenia or schizoaffective disorder in the FACE-SZ database were collected between 2010 and 2021. We estimated the association between objective global cognitive performance and the 27 scales, the number of psychotropic drugs, and chlorpromazine and lorazepam equivalents in bivariable regressions in a cross-sectional design. We then adjusted the bivariable models with covariates: the predictors significantly associated with cognitive performance in multiple linear regressions were considered to have good concurrent validity to assess cognitive performance.

Results

Eight scales, the number of psychotropic drugs, and drug equivalents were significantly associated with cognitive impairment. The number of psychotropic drugs, the most convenient predictor to compute, was associated with worse executive function (Standardized β = -0.12, p = .004) and reasoning (Standardized β = -0.08, p = .037).

Conclusion

Anticholinergic burden, the number of psychotropic drugs, and drug equivalents were weakly associated with cognition, thus suggesting that cognitive impairment in schizophrenia and schizoaffective disorder is explained by factors other than medication. The number of psychotropic drugs was the most parsimonious method to assess the risk of iatrogenic cognitive impairment.

The volume of gray matter mediates the relationship between glucolipid metabolism and neurocognition in first-episode, drug-naïve patients with schizophrenia

We aimed to examine the hypotheses that glucolipid metabolism is linked to neurocognition and gray matter volume (GMV) and that GMV mediates the association of glucolipid metabolism with neurocognition in first-episode, drug-naïve (FEDN) patients with schizophrenia. Parameters of glucolipid metabolism, neurocognition, and magnetic resonance imaging were assessed in 63 patients and 31 controls. Compared to controls, patients exhibited higher levels of fasting glucose, triglyceride, and insulin resistance index, lower levels of cholesterol and high-density lipoprotein cholesterol, poorer neurocognitive functions, and decreased GMV in the bilateral insula, left middle occipital gyrus, and left postcentral gyrus. In the patient group, triglyceride levels and the insulin resistance index exhibited a negative correlation with Rapid Visual Information Processing (RVP) mean latency, a measure of attention within the Cambridge Neurocognitive Test Automated Battery (CANTAB), while showing a positive association with GMV in the right insula. The mediation model revealed that triglyceride and insulin resistance index had a significant positive indirect (mediated) influence on RVP mean latency through GMV in the right insula. Glucolipid metabolism was linked to both neurocognitive functions and GMV in FEDN patients with schizophrenia, with the effect pattern differing from that observed in chronic schizophrenia or schizophrenia comorbid with metabolic syndrome. Moreover, glucolipid metabolism might indirectly contribute to neurocognitive deficits through the mediating role of GMV in these patients.

A pilot study to examine the association between COX-2 rs5275 polymorphism and the response to repetitive transcranial stimulation in schizophrenia

High frequency (HF)-rTMS has been shown to improve cognitive functions in patients with schizophrenia (SCZ). This study aimed to investigate whether COX-2 rs5275 variants were associated with cognitive improvements following rTMS treatment in patients with SCZ. Forty-eight hospitalized patients with SCZ were assigned to the neuronavigation HF-rTMS group and 28 patients to the sham group over left DLPFC for 1 month. Cognitive function was evaluated using the repeatable battery for the assessment of neuropsychological status (RBANS) at weeks 0 and 4. COX-2 rs5275 polymorphism was genotyped by a technician. At baseline, C allele carriers showed better cognitive performance relative to patients with TT homozygote. Additionally, C allele carriers had greater improvement in memory from the follow-up to baseline following rTMS stimulation, while patients with the TT genotype showed no significant improvement in memory index. More importantly, we found that COX-2 rs5275 was correlated with the response to rTMS after controlling for the covariates. This study data indicate that COX-2 rs5275 was associated with improvements in immediate memory after HF-rTMS treatment in patients with SCZ. rTMS shows an effect on memory only in C allele carriers, but not in those with the TT genotype.

Selective processing in attention and memory in schizophrenia: A meta-analysis of the negative priming effect

Individuals with schizophrenia show impairments in a variety of selective attention tasks. Research on the negative priming (NP) effect in schizophrenia has yielded mixed evidence. This meta-analysis aimed to examine the NP effect exhibited by patients with schizophrenia and the impact of study methodology on findings. The methods and reporting of this meta-analysis followed the PRISMA guideline. Eligible studies were identified through primary literature search in MEDLINE, PsycInfo, PsycArticles, and Embase and secondary search based on included studies and important reviews. Three-level random effects-models were used to summarize between-group differences in the raw NP score, as well as the NP ratio and baseline reaction time (RT) as secondary outcomes. We identified 1383 studies published between 1966 and 2022 and reviewed 27 studies that consist of 627 patients with schizophrenia and 653 controls in total. Compared to healthy controls, patients with schizophrenia showed a mildly reduced raw NP score with marginal significance, Hedges' g = -0.16, 95% confidence interval (CI) -0.35 to 0.02, p = 0.084. However, analysis of a subsample of studies indicated a significant, moderate reduction in the NP ratio among patients, g = -0.52, 95% CI -0.91 to -0.14; p = 0.014. Moderator analyses revealed a longer illness duration as predictive of a more reduced NP effect. This meta-analysis lends tentative evidence to impaired attention or memory process as measured by the NP task in schizophrenia. More research is needed to substantiate our results and clarify the impact of study design and patient characteristics on findings.

Neurocognitive correlates of the varied domains of outcomes at 20 year follow-up of first-episode psychosis

Little is known about long-term outcomes of the first episode of psychosis (FEP) other than in the symptomatic domain. We hypothesised that cognitive impairment is associated with poorer multi-domain outcomes at a long-term follow-up of FEP patients. We followed-up 172 FEP patients for a mean of 20.3 years. Ten outcome dimensions were assessed (symptomatic, functional and personal recovery, social disadvantage, physical health, suicide attempts, number of episodes, current drug use, chlorpromazine equivalent doses (CPZ), and schizophrenia/schizoaffective disorder final diagnosis). Cognition was assessed at follow-up. Processing speed and verbal memory deficits showed significant associations with poor outcomes on symptomatic, social functioning, social disadvantage, higher number of episodes, and higher CPZ. Significant associations were found between visual memory impairments were significantly associated with low symptomatic and functional recovery, between attentional deficits and a final diagnosis of schizophrenia/schizoaffective disorder, and between social cognition deficits and poor personal recovery.Lower cognitive global scores were significantly associated with all outcome dimensions except for drug abuse and physical status. Using multiple outcome dimensions allowed for the inclusion of the patients' perspective and other commonly neglected outcome measures. Taken together, cognitive impairment in FEP patients is strongly related to poor performance on several outcome dimensions beyond symptomatic remission.

Building a neurocognitive profile of suicidal risk in severe mental disorders

BACKGROUND

Research on the influence of neurocognitive factors on suicide risk, regardless of the diagnosis, is inconsistent. Recently, suicide risk studies propose applying a trans-diagnostic framework in line with the launch of the Research Domain Criteria Cognitive Systems model. In the present study, we highlight the extent of cognitive impairment using a standardized battery in a psychiatric sample stratified for different degrees of suicidal risk. We also differentiate in our sample various neurocognitive profiles associated with different levels of risk.

MATERIALS AND METHODS

We divided a sample of 106 subjects into three groups stratified by suicide risk level: Suicide Attempt (SA), Suicidal Ideation (SI), Patient Controls (PC) and Healthy Controls (HC). We conducted a multivariate Analysis of Variance (MANOVA) for each cognitive domain measured through the standardized battery MATRICS Consensus Cognitive Battery (MCCB).

RESULTS

We found that the group of patients performed worse than the group of healthy controls on most domains; social cognition was impaired in the suicide risk groups compared both to HC and PC. Patients in the SA group performed worse than those in the SI group.

CONCLUSION

Social cognition impairment may play a crucial role in suicidality among individuals diagnosed with serious mental illness as it is involved in both SI and SA; noteworthy, it is more compromised in the SA group fitting as a marker of risk severity.

The Relationship between Cognitive Functions and Psychopathological Symptoms in First Episode Psychosis and Chronic Schizophrenia

Impairments in cognitive functions are one of the main features of schizophrenia. A variety of factors can influence the extent of cognitive deficits. In our study, we examined the severity of cognitive deficits at different stages of the disease and the relationship between psychopathological symptoms and cognitive functions. We recruited 32 patients with first-episode psychosis (FEP), 70 with chronic schizophrenia (CS), and 39 healthy controls (HC). Psychopathological symptoms were evaluated with the Positive and Negative Syndrome Scale (PANSS) and cognitive functions were measured with the MATRICS Cognitive Consensus Battery (MCCB). Cognitive deficits were present in both FEP and CS participants. CS individuals had lower overall scores and poorer working memory; however, clinical variables appeared to play a significant role in these scores. In FEP, disorganization correlated negatively with verbal and visual learning and memory, social cognition, and overall score; negative symptoms negatively correlated with social cognition. In CS participants, disorganization correlated negatively with speed of processing, reasoning, problem solving, and overall score; negative symptoms were negatively correlated with speed of processing, visual learning, memory, and overall score; positive symptoms were negatively correlated with reasoning and problem solving. Our findings indicate that psychopathological symptoms have a significant impact on cognitive functions in FEP and CS patients.

Cognitive functioning in first episode psychosis. Gender differences and relation with clinical variables

AIMS

to study the differences in cognitive functioning in patients and controls. In addition, study the influence of symptoms, cannabis consumption, chlorpromazine doses, DUP and IQ in cognitive performance in patients, both in the total sample and divided by gender.

METHODS

70 first episode psychosis patients and 63 healthy controls (HC) participated in the study and were assessed with the MATRICS battery and the Vocabulary subtest of WAIS-IV. Symptoms in FEP patients were evaluated with the Emsley factors of the PANSS scale.

RESULTS

patients showed lower scores than controls in all cognitive domains studied. There were no significant differences between FEP men and FEP women, but we found gender differences in favour of women in processing speed, working memory and composite total scored domains in the HC group. Finally, symptoms and Chlorpromazine doses showed an influence on cognitive performance in the total FEP sample. When splitting the sample by gender, positive symptoms may be more detrimental to women's cognitive functioning, while disorganized symptoms may play the most important role in cognitive performance in men.

CONCLUSIONS

patients showed worse cognitive performance in all cognitive domains compared to healthy controls. In our FEP sample, gender does not seem to influence cognitive performance measured with the MATRICS. Severity of symptoms influences positively in cognitive performance. The dose of Chlorpromazine and symptoms are influential variables to be taken into account in cognition rehabilitation programs.

Social cognition and its relationship with sociodemographic, clinical, and psychosocial variables in first-episode psychosis

People with first episode of psychosis (FEP) show deficits in social cognition, which have been linked to several sociodemographic, clinical, and psychosocial variables. The aim of the present research was to study social cognition as a whole measure in people with FEP comparing it with a healthy control sample, to study gender differences, and to examine the relationship between sociodemographic, clinical, and psychosocial variables and social cognition in the onset of psychosis. A descriptive, cross-sectional study was performed. The study sample consisted of 63 people (18 females; 45 males) with a diagnosis of FEP and a healthy control group (78 participants: 38 females; 40 males). All the participants were assessed with the social cognitive domain of the MATRICS Consensus Cognitive Battery (MCCB) and several questionnaires related to studied variables. Our results indicated that compared with healthy controls, people with FEP showed social cognition deficits. Furthermore, premorbid IQ was the most relevant variable in social cognition performance in FEP sample. The findings of the present research may be taken into account in clinical practice to improve the intervention with people with FEP.

Relationship of Corpus Callosum Integrity with Working Memory, Planning, and Speed of Processing in Patients with First-Episode and Chronic Schizophrenia

There is a paucity of reports examining the relationship between the integrity of the corpus callosum (CC) and different aspects of cognitive functioning in patients with first-episode (FES) and chronic schizophrenia (CS) simultaneously; furthermore, what results exist are inconclusive. We used diffusion tensor imaging tractography to investigate differences in integrity in five regions of the CC between FES, CS, and healthy controls (HC). Additionally, we analyzed correlations between these regions' integrity and working memory, planning, and speed of processing. Eighteen patients with FES, 55 patients with CS, and 30 HC took part in the study. We assessed cognitive functions with four tasks from Measurement and Treatment Research to Improve Cognition in Schizophrenia. Patients with CS showed lower fractional anisotropy (FA) in Region 5 (statistical trend) and higher mean diffusivity (MD) in Regions 4 and 5 than HC, and patients with FES had higher MD in Region 3 (statistical trend) than HC. Both clinical groups performed worse on working memory and speed of processing tasks than HC, and patients with CS scored worse than HC on independent planning, and worse than FES and HC on dependent planning. Moreover, in patients with CS, MD in Region 3 was correlated with verbal working memory. Our results suggest that patients with FES and CS are characterized by impaired integrity of the middle and posterior CC, respectively. We confirmed that both clinical groups have cognitive impairments. Moreover, the integrity of the middle CC may influence planning in patients with CS.

[ADHD during childhood and subsequent psychotic disorder: A link?]

OBJECTIVES

Attention Deficit with/without Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder with frequent comorbid psychiatric disorders. Several studies have underlined the increased risk of developing a psychotic disorder subsequent to a childhood ADHD. The aim of our review is not only to clarify this association and the related physiopathology but also to understand the consequences for therapeutic management.

METHODS

We processed a narrative review of available literature based on a research of the PubMed database. Articles related to ADHD and psychotic disorder on a genetical, clinical or biological level were selected by one of the authors.

RESULTS

ADHD and psychotic disorders share neonatal, environmental, and genetic risk factors. On a neurobiological level, both disorders are concerned by a dysfunction of the dopaminergic system with an abnormal regulation of dopaminergic neurons' phasic and tonic activity. Our review aims to explain the « dynamic » model of dopaminergic dysfunctions and propose some guidance for pharmacological treatment of ADHD, with or without psychotic disorder. This model offers a better understanding of why methylphenidate is not associated to an increased risk of psychotic disorder and could act as a protective factor. Association between ADHD and psychotic disorders could be explained by some comorbidities such as substance use disorders which are frequently associated with both conditions and could act as mediator in the genesis of psychotic disorders following ADHD during childhood. Our review also focuses on an epidemiological bias that could be found in some studies such as possible diagnostic errors, as some non-specific clinical signs could be found in both late diagnosed ADHD and in "at risk mental state" of psychosis.

CONCLUSION

ADHD and psychotic disorders share common risk factors, neurobiological pathways and clinical symptoms. Perspectives for future studies are proposed considering a dimensional aspect of psychiatric disorders using, for example, Research Domain Criteria and exploring the link between the two conditions.

Suicidal ideation in first-episode psychosis: Considerations for depression, positive symptoms, clinical insight, and cognition

BACKGROUND

Suicide is a leading cause of death for individuals with psychosis. Although factors influencing suicide risk have been studied in schizophrenia, far less is known about factors that protect against or trigger increased risk during early-stage and first episode of psychosis. This study examined whether depression, psychotic symptoms, clinical insight, and cognition were associated with suicide ideation among individuals with first-episode psychosis.

METHODS

Data were obtained from the Recovery After an Initial Schizophrenia Episode (RAISE) project. Participants (n = 404) included adults between ages 15 and 40 in a first episode of psychosis. Measurement included the Positive and Negative Syndrome Scale, Brief Assessment of Cognition in Schizophrenia, and Calgary Depression Scale for Schizophrenia. A logistic regression model evaluated clinical and cognitive variables as predictors of suicidal ideation.

RESULTS

Greater positive symptoms (OR = 1.085, p < .01) and depression (OR = 1.258, p < .001) were associated with increased likelihood of experiencing suicidal ideation during the RAISE project. Meanwhile, stronger working memory (OR = 0.922, p < .05) and impaired clinical insight (OR = 0.734, p < .05) were associated with a decreased likelihood of experiencing suicidal ideation.

CONCLUSION

The likelihood of experiencing suicidal ideation was significantly increased when positive and depressive symptoms were present, and significantly decreased when clinical insight was poorer and working memory stronger. These findings have important implications for the role of cognition and insight in risk for suicide ideation in early-stage psychosis, which may aid in improving the prediction of suicide behaviors and inform clinical decision-making over the course of the illness.

Stability of Verbal Fluency in Outpatients with Schizophrenia

While it is well established that individuals with schizophrenia exhibit a wide range of neurocognitive deficits, there is significant heterogeneity in this regard. Impairments in verbal fluency appear to present consistently across most individuals with the illness. The present study examined the stability of verbal fluency abilities in chronic schizophrenia longitudinally. It was hypothesized that semantic but not phonemic verbal fluency performance would be stable over one year. Data was extracted from a larger study that followed 53 outpatients (70% male; mean age = 39.2 years) diagnosed with schizophrenia or schizoaffective disorder. At each testing interval (baseline, 6, and 12 months), the Brief Assessment of Cognition in Schizophrenia was administered, which included phonemic (i.e., F, S) and semantic (i.e., animals) verbal fluency tasks. No significant differences were found across time points for semantic and phonemic verbal fluency with respect to mean number of words generated, clustering, and switching. The findings provide evidence of stability in semantic and phonemic verbal fluency abilities in chronic schizophrenia. Moving forward, it would be valuable to examine verbal fluency performance longitudinally across multiple stages of illness (i.e., clinically high-risk to chronic schizophrenia).

Verbal memory measurement towards digital perspectives in first-episode psychosis: A review

BACKGROUND

Even in the early phases of psychotic spectrum illnesses such as schizophrenia, patients can experience cognitive decline or deficits prior to the onset of psychotic symptoms such as delusions and hallucinations. In this systematic review, we assessed which verbal memory assessments are most widely used in first-episode psychosis and may be applied via digital technologies (smartphone applications, etc.) for use in early detection.

METHODS

In November 2019, we searched for studies measuring verbal memory in first episode psychosis or schizophrenia over the past 10 years on PubMed and PsycINFO. We screened abstracts of these studies and excluded review studies. Full-texts of included studies were used to identify the verbal memory measurement tests, follow-up frequencies, and sample sizes.

RESULTS

We screened 233 reports and found that 120 original research studies measured verbal memory in first episode psychosis over the past 10 years. Four of these studies specified using a computer, 24 (20%) used a paper-pen format, 1(1%) used both, and 91 (76%) studies did not specify their administration tools or suggest there were offered in digital formats. Thirty-five (30%) studies had follow-up measurements of verbal memory, while 85 (70%) had only a single verbal memory measurement.

DISCUSSION

While many scales are commonly used to measure verbal memory in first episode psychosis, they are not often administered via digital technology. There is an emerging opportunity to administer these and other tests via digital technologies for expanding access to early detection of cognitive decline in clinical high risk and first-episode psychosis.

Neurocognitive functioning in patients with first-episode schizophrenia: results of a prospective 15-year follow-up study

To evaluate the course of neuropsychological impairment, patients with first-episode schizophrenia and healthy controls were assessed with a comprehensive test battery at the time of index treatment and after a 5- and 15-year follow-up period. Summary scores for verbal intelligence (VBI), spatial organization, verbal fluency, verbal learning, semantic memory, visual memory, delay/retention rate, short-term memory, visual-motor processing and attention (VSM) and abstraction/flexibility were constructed. Our results show that neurocognitive functioning is impaired already at the onset of schizophrenia and remains stable over the 15-year follow-up period with an improvement in VBI. With regard to the presence of a deficit syndrome, it became apparent that the group with a deficit syndrome showed a deterioration of neurocognitive functions during the follow-up period, most pronounced in VSM. On the other hand, the group without a deficit syndrome showed an improvement in neurocognitive functions at the 15-year follow-up, which exceeded the learning effects of healthy control subjects. Neurocognitive performance at index assessment strongly predicted the performance at the 15-year follow-up. Most likely due to the small sample size, there were only weak associations between treatment with different types of neuroleptics and neurocognitive performance.

Associations between facial affect recognition and neurocognition in subjects at ultra-high risk for psychosis: A case-control study

The nature of facial affect recognition (FAR) deficits in subjects at ultra-high risk (UHR) for psychosis remains unclear. In schizophrenia, associations between FAR impairment and poor neurocognition have been demonstrated meta-analytically, but this potential link is understudied in the UHR population. Our study investigated a cross-sectional sample of UHR subjects (n = 22) and healthy controls (n = 50), with the Degraded Facial Affect Recognition (DFAR) Task and a neurocognitive test battery. Our primary aims were 1. to examine associations between FAR and neurocognition in UHR subjects and 2. to examine if associations differed between cases and controls. The secondary aim was to examine group differences in FAR and neurocognitive performance. In UHR subjects, FAR was significantly associated with working memory, a neurocognitive composite score and intelligence, and at trend level with most other assessed neurocognitive domains, with moderate to large effect sizes. There were no significant associations in controls. Associations between FAR and working memory and the neurocognitive composite score differed significantly between cases and controls. UHR subjects did not differ from controls on DFAR Task performance but showed significant deficits in three of six neurocognitive domains. Results may suggest that FAR is associated with working memory in UHR subjects, possibly reflecting a neurocognitive compensatory mechanism.

Effects of an extrinsic motivator on the evaluation of cognitive and daily living functions in patients with schizophrenia

We investigated the effect of an extrinsic motivator on the MATRICS Consensus Cognitive Battery (MCCB) and UCSD Performance-Based Skills Assessment (UPSA) scores, which assess cognitive and daily living functions, in patients with schizophrenia. We enrolled 60 clinically stable patients with schizophrenia and allocated them to the motivator or control group. We conducted baseline assessments of cognitive function using the MCCB, daily living function using the UPSA, clinical symptoms, and psychosocial characteristics in both groups. In the retrial, we initially evaluated clinical symptoms. Next, we assigned an extrinsic motivator to the motivator group and again assessed cognitive function and daily living function using the MCCB and UPSA. Statistical analyses were performed using t-tests, Chi-square tests, Fisher's exact test, repeated measures analysis of variance, and logistic regression analysis. We found significant time × group interactions in processing speed, verbal learning, visual learning, and composite scores of MCCB. There were no significant interactions in UPSA scores. The meaningful change rates of social cognition and composite scores in MCCB were significantly higher in the motivator group than in the control group. After adjusting for additional variables, the extrinsic motivator had a significant effect on the meaningful MCCB composite score change. Conclusively, our findings suggest beneficial effects of extrinsic motivator on the MCCB score in patients with schizophrenia. In the future, the implementation and interpretation of the MCCB considering the motivation is necessary.

Effects of transcranial direct current stimulation on cognition and symptoms in Chinese patients with schizophrenia✰

There is preliminary evidence that transcranial direct current stimulation(tDCS) may improve symptoms and cognitive function in schizophrenia, but the generalizability of these results needs further investigation. We present a study of the effects of active vs. sham tDCS on cognition and symptoms in a sample of 45 Chinese patients with schizophrenia who showed significant cognitive deficits and were treated for 10 sessions with active or sham tDCS. Psychiatric symptoms were assessed by PANSS scores, and cognitive symptoms assessed by MATRICS battery and other tests. There were no differences between cognitive or symptom scores between subjects treated with active vs. sham tDCS tested within 1-2 days after the end of the 10th session. However, two weeks later subjects treated with active tDCS showed significantly more improvements on MATRICS Speed of Processing domain. MATRICS Overall Composite and a CogState measure related to accuracy on a 1-back working memory task were improved at two weeks in statistical tests without multiple corrections. The improvement in cognitive test scores 2 weeks after the last tDCS session, suggests longer term effects may be related to changes in neuroplasticity induced by 10 sessions of tDCS. The lack of significant changes in cognition shortly after the completion of 10 tDCS sessions contrasts with our earlier positive findings in U.S. patients with schizophrenia.

The Complex Relationship Among Formal Thought Disorders, Neurocognition, and Functioning in Nonacutely Ill Schizophrenia Patients

The aims of the present study were to 1) evaluate clinical differences between patients suffering from schizophrenia (SZ) with mild versus moderate/severe formal thought disorder (FTD); 2) explore relationships between dimensions of FTD, neuropsychological domains, and global functioning; and 3) compare clinical dimensions of FTD in early and late SZ. One hundred thirty-six individuals with schizophrenia were recruited and evaluated during a nonacute phase of illness. FTD was assessed with the Thought, Language, and Communication Scale. Partial correlations, t-tests, and stepwise regression were undertaken to address the study aims. Patients with moderate/severe FTD performed worse than those with mild FTD for processing speed, reasoning and problem solving, and social cognition, and demonstrated poorer global functioning. Early SZ did not differ from late SZ in terms of negative FTD and difficulty in abstract thinking (DAT). Negative FTD was correlated with reasoning and problem solving; DAT was correlated with social cognition. All clinical dimensions of FTD, regardless of neurocognitive impairment, accounted for a significant amount of variance in global functioning. FTD predicted global functioning, regardless of neurocognitive factors. Due to their stability in different phases of the course of the disease and their strong relationship with other core variables, Neg-FTD and DAT should be investigated as an intermediate phenotype of the illness.

The effect of anticholinergic burden on cognitive and daily living functions in patients with schizophrenia

OBJECTIVE

This study aimed to explore the association between medication-associated anticholinergic burden and cognitive and daily living functions in patients with schizophrenia.

METHODS

Sixty patients with schizophrenia were recruited. We used the Anticholinergic Drug Scale (ADS) for evaluating medication-associated anticholinergic burden. The MATRICS Consensus Cognitive Battery (MCCB) and the University of California San Diego Performance-based Skills Assessment (UPSA) were used for evaluating cognitive and daily living functions. To assess clinical symptoms, psychiatrists conducted interviews using the Positive and Negative Syndrome Scale and the Calgary Depression Scale for Schizophrenia.

RESULTS

Subjects were divided into low (n = 31) and high (n = 29) anticholinergic burden based on ADS scores of 3 or more. The "high ADS" group had poorer cognitive (composite MCCB score, p < 0.001) and daily living functions (total UPSA score, p = 0.001) than the "low ADS" group. Medication-associated anticholinergic burden was negatively correlated with cognitive functions (composite MCCB score, r = -0.512, p < 0.001) and daily living functions (total UPSA score, r = -0.355, p = 0.005). A regression analysis showed that anticholinergic burden significantly explained the decline in cognitive functions (composite MCCB score, R² = 0.262, p < 0.001) and daily living functions (total UPSA score, R² = 0.126, p = 0.005). Explanatory power was reduced after a covariate adjustment, but the effects of the composite MCCB score (p = 0.013) and of the transportation domain score of the UPSA (p = 0.048) remained significant.

CONCLUSIONS

Our analysis shows that anticholinergic burden reduces cognitive and daily living functions in patients with schizophrenia. A drug strategy with minimal anticholinergic burden may be helpful to patients if it does not adversely affect clinical symptoms.

Basic self-disturbance, neurocognition and metacognition: A pilot study among help-seeking adolescents with and without attenuated psychosis syndrome

AIM

The goal of this pilot study was to assess the association between basic self-disturbance (SD) and deficits in neurocognitive and metacognitive functioning among help-seeking adolescents with and without attenuated psychosis syndrome (APS).

METHODS

Sixty-one non-psychotic, help-seeking adolescents (age 13-18) were assessed with the examination of anomalous self-experience, the structured interview for prodromal syndromes and a new metacognitive approach to neurocognitive assessment applied to two non-social (executive functions and verbal memory) and two social (theory of mind and emotion recognition) domains. After each answer, subjects were also requested to indicate their level of confidence in the answer and to decide whether they desired it to be "counted" toward their total score on the task. Each volunteered answer earned a 5-cent gain if correct, but an equal fine if wrong.

RESULTS

As hypothesized, metacognitive monitoring and control had a significant contribution to the prediction of SD over and above neurocognitive functioning and attenuated psychotic symptoms. However, the direction of this association was positive rather than negative. Also, inconsistent with or hypothesis, it was not moderated by the presence of APS.

CONCLUSIONS

These pilot results provide preliminary support a modest association between SD and metacognition, which is not reducible to neurocognition and APS. In addition, they raise an intriguing possibility regarding metacognitive monitoring and control being indicators of hyper-reflectivity that characterizes individuals with SD. However, further research with larger samples and high-stress assessment conditions are needed to assess this possibility.

Cognitive Profile in Ultra High Risk for Psychosis and Schizophrenia: A Comparison Using Coordinated Norms

Background: Cognitive impairment is not only a core aspect of schizophrenia but also commonly observed in help-seeking youth at ultra high risk for psychosis (UHR), with potential implications for prognosis and individualized treatment. However, there is no consensus on the cognitive profile in the UHR state, partly due to lack of valid comparisons of performance in established schizophrenia and UHR. Objectives: To compare the cognitive functioning and profile of UHR subjects to a sample with schizophrenia, they were split into two groups based on duration of illness. Comparisons were made using coordinated norms based on healthy controls reflecting the younger UHR age spectrum. Methods: Participants for UHR (n = 51) and schizophrenia groups (n = 19 and n = 22) were included from the Prevention of Psychosis and Bergen Psychosis 2 projects. All subjects completed a comprehensive neurocognitive test battery aiming to measure speed of processing, working memory, verbal learning, reasoning, and problem solving, as well as visual problem solving. Cognitive functioning was compared between groups based on coordinated norms using z-scores derived by regression modeling from an age-matched healthy control group (n = 61). Results: UHR subjects showed significantly impaired speed of processing (p < 0.001) working memory (p = 0.042) and verbal learning, reasoning, and problem solving (p = 0.007) as compared to the control group. Visual problem-solving skills appeared unimpaired. UHR subjects significantly outperformed the schizophrenia group with duration of illness >3 years for speed of processing and working memory (both p < 0.001). There were no significant differences in performance between the UHR group and the group with duration of schizophrenia <3 years. Conclusion: Cognitive performance is impaired in UHR subjects as compared to healthy controls and should thus be monitored when a person is deemed at high risk of psychotic illness. Spatial skills, as measured by tests using physical objects, appear less affected than other domains. The pattern of impairment is similar to that of a group with recent onset schizophrenia but is less severe than in a group with duration of illness <3 years.

Global and Specific Profiles of Executive Functioning in Prodromal and Early Psychosis

Objective: Numerous reports on neurocognitive functioning deficits in individuals at clinical high risk (CHR) and first-episode psychosis (FEP) patients suggest particular deficits in executive functioning (EF). However, to date, most of the studies have administered a single or a few EF tests to participants, and few investigations have examined the different components of EF to identify specific subdomains of relative strength and weakness. Method: Forty CHR subjects, 85 FEP patients, and 85 healthy controls (HCs) were assessed with a neuropsychological battery to elucidate the profiles of EF in the subdomains of shift, attention, fluency, and planning. Results: In the subdomains of shift, attention, and fluency, CHR individuals and FEP patients showed deficits compared to HC. The post hoc analysis revealed that CHR individuals had comparable attention shifting and phonemic fluency compared to FEP. CHR showed intermediate deficits between FEP and HCs in spatial working memory and semantic fluency, and the largest effect size was observed in semantic fluency both for CHR and FEP. Conclusion: Overall, the findings of this study, in addition to providing detailed profiles of EF in prodromal and early psychosis patients, highlight the informative value of the specific subdomains of semantic fluency and spatial working memory.

What accounts for poor functioning in people with schizophrenia: a re-evaluation of the contributions of neurocognitive v. attitudinal and motivational factors

BACKGROUND

Neurocognitive deficits are often seen as core features of schizophrenia, and as primary determinants of poor functioning. Yet, our clinical observations suggest that individuals who score within the impaired range on standardized tests can reliably perform better in complex real-world situations, especially when performance is embedded within a positive socio-affective context.

METHODS

We analyzed literature on the influence of non-neurocognitive factors on test performance in order to clarify their contributions.

RESULTS

We identified seven non-neurocognitive factors that significantly contribute to neurocognitive test performance: avolition, dysfunctional attitudes, effort, stress, negative emotions, asociality, and disorganized symptoms. We then proposed an alternative model based on dysfunctional (e.g. defeatist) attitudes and their consequences for motivation and sustained task engagement. We demonstrated that these factors account for substantial variance in negative symptoms, neurocognitive test performance, and functional outcomes. We then demonstrated that recovery-oriented cognitive therapy - which is derived from this alternative model and primarily targets dysfunctional beliefs - has been successful in the treatment of low functioning individuals with schizophrenia.

CONCLUSION

The contributions of neurocognitive impairments to poor real-world functioning in people with schizophrenia may be overstated in the literature, and may even be limited relative to non-neurocognitive factors. We offer suggestions for further research to more precisely quantify the contributions of attitudinal/motivation v. neurocognitive factors in schizophrenia.

Comparing cognitive clusters across first- and multiple-episode of psychosis

Cognitive impairments in psychotic disorders (PD) present heterogeneously across patients. Between 2 and 5 clusters have been identified in previous studies with first-episode (FEP) and multiple-episodes of psychosis (MEP) patients suggesting different profiles of impairment. Past findings suggest there are differences between FEP and MEP patients regarding severity and number of affected cognitive domains. Heterogeneity of cognitive deficits in PD has perhaps hindered our understanding of their course. The present study compared non-affective FEP and MEP patients to assess whether illness chronicity could influence cognitive impairment profiles. We analyzed cognitive data, collected with the Cogstate Schizophrenia Battery, of FEP and MEP patients using cluster analysis. We compared clustering methods to obtain a more robust solution. For FEP patients, data were collected at their entry to a specialized clinic; the MEP group consisted of in- and outpatients. Results suggested cognitive heterogeneity was similar in FEP and MEP samples, although in different proportions. Three clusters were identified as the most stable solution and comprised groups of patients with either 1- no cognitive impairment (over-representation of FEP), 2- generalized deficits (over-representation of MEP), or 3- intermediate impairments. These findings encourage early interventions adapted to the profile of impairment.

Correlates of neurocognitive functions in individuals at ultra-high risk for psychosis - A 6-month follow-up study

Cognitive deficits are evident at the prodromal phase of psychosis. It has been noted that brain-derived neurotrophic factor (BDNF) is correlated with cognition in both preclinical and clinical studies. However, to our knowledge, no study has evaluated blood BDNF levels and their association with cognitive impairment in individuals at ultra-high risk for psychosis (UHR). We included 13 individuals at UHR and 30 healthy controls (HC) matched by sex, age, and educational level. Plasma BDNF levels were measured at baseline and 6 months. Neurocognitive functions (executive functions, speed of processing, verbal learning and memory, working memory) were examined at 6 months. Regression analyses were conducted to examine the relationship between BDNF levels and cognitive performance. BDNF levels were lower in UHR group than in HC group both at baseline and at 6 months (P = 0.001, and P = 0.007, respectively). There were no associations between plasma BDNF levels and all of the cognitive domains in both groups. Our findings showed that peripheral BDNF levels were not related to cognitive deficits in UHR and HC groups while the lower BDNF level in the former persisted up to 6 months. Further research is needed in a large sample.

Neurocognitive dysfunction in subjects at clinical high risk for psychosis: A meta-analysis

Findings of neurocognitive dysfunction in subjects at Clinical High Risk for Psychosis (CHR-P) have been controversial. This meta-analysis systematically examined studies of neurocognitive functions using the MATRICS Consensus Cognitive Battery (MCCB) in CHR-P. An independent literature search of both English and Chinese databases was conducted by two reviewers. Standardized mean difference (SMD) was calculated using a random effects model to evaluate the effect size of the meta-analytic results. Six case-control studies (n = 396) comparing neurocognitive functions between CHR-P subjects (n = 197) and healthy controls (n = 199) using the MCCB were identified; 4 (66.7%) studies were rated as "high quality". Compared to healthy controls, CHR-P subjects showed impairment with large effect size in overall cognition (n = 128, SMD = -1.00, 95%CI: -1.38, -0.63, P < 0.00001; I² = 2%), processing speed (SMD = -1.21) and attention/vigilance (SMD = -0.83), and with medium effect size in working memory (SMD = -0.76), reasoning and problem solving (SMD = -0.71), visual (SMD = -0.68) and verbal learning (SMD = -0.67). No significant difference between CHR-P subjects and controls was found regarding social cognition (SMD = -0.33, 95%CI: -0.76, 0.10, P = 0.14; I² = 70%) with small effect size. Apart from social cognition, CHR-P subjects performed worse than healthy control in all MCCB cognitive domains, particularly in processing speed, attention/vigilance and working memory.

Treatment with levetiracetam improves cognition in a ketamine rat model of schizophrenia

Imbalance in neural excitation and inhibition is associated with behavioral dysfunction in individuals with schizophrenia and at risk for this illness. We examined whether targeting increased neural activity with the antiepileptic agent, levetiracetam, would benefit memory performance in a preclinical model of schizophrenia that has been shown to exhibit hyperactivity in the hippocampus. Adult rats exposed to ketamine subchronically during late adolescence showed impaired hippocampal-dependent memory performance. Treatment with levetiracetam dose-dependently improved memory performance of the ketamine-exposed rats. In contrast, the antipsychotic medication risperidone was not effective in this assessment. Levetiracetam remained effective when administered concurrently with risperidone, supporting potential viability of adjunctive therapy with levetiracetam to treat cognitive deficits in schizophrenia patients under concurrent antipsychotic therapy. In addition to its pro-cognitive effect, levetiracetam was also effective in attenuating amphetamine-induced augmentation of locomotor activity, compatible with the need for therapeutic treatment of positive symptoms in schizophrenia.

From the psychosis prodrome to the first-episode of psychosis: No evidence of a cognitive decline

Cognitive deficits have an important role in the neurodevelopment of schizophrenia and other psychotic disorders. However, there is a continuing debate as to whether cognitive impairments in the psychosis prodrome are stable predictors of eventual psychosis or undergo a decline due to the onset of psychosis. In the present study, to determine how cognition changes as illness emerges, we examined baseline neurocognitive performance in a large sample of helping-seeking youth ranging in clinical state from low-risk for psychosis through individuals at clinical high-risk (CHR) for illness to early first-episode patients (EFEP). At baseline, the MATRICS Cognitive Consensus battery was administered to 322 individuals (205 CHRs, 28 EFEPs, and 89 help-seeking controls, HSC) that were part of the larger Early Detection, Intervention and Prevention of Psychosis Program study. CHR individuals were further divided into those who did (CHR-T; n = 12, 6.8%) and did not (CHR-NT, n = 163) convert to psychosis over follow-up (Mean = 99.20 weeks, SD = 21.54). ANCOVAs revealed that there were significant overall group differences (CHR, EFEP, HSC) in processing speed, verbal learning, and overall neurocognition, relative to healthy controls (CNTL). In addition, the CHR-NTs performed similarly to the HSC group, with mild to moderate cognitive deficits relative to the CTRL group. The CHR-Ts mirrored the EFEP group, with large deficits in processing speed, working memory, attention/vigilance, and verbal learning (>1 SD below CNTLs). Interestingly, only verbal learning impairments predicted transition to psychosis, when adjusting for age, education, symptoms, antipsychotic medication, and neurocognitive performance in the other domains. Our findings suggest that large neurocognitive deficits are present prior to illness onset and represent vulnerability markers for psychosis. The results of this study further reinforce that verbal learning should be specifically targeted for preventive intervention for psychosis.

Buspirone Counteracts MK-801-Induced Schizophrenia-Like Phenotypes through Dopamine D3 Receptor Blockade

Background: Several efforts have been made to develop effective antipsychotic drugs. Currently, available antipsychotics are effective on positive symptoms, less on negative symptoms, but not on cognitive impairment, a clinically relevant dimension of schizophrenia. Drug repurposing offers great advantages over the long-lasting, risky and expensive, de novo drug discovery strategy. To our knowledge, the possible antipsychotic properties of buspirone, an azapirone anxiolytic drug marketed in 1986 as serotonin 5-HT_1A receptor (5-HT_1AR) partial agonist, have not been extensively investigated despite its intriguing pharmacodynamic profile, which includes dopamine D₃ (D₃R) and D₄ receptor (D₄R) antagonist activity. Multiple lines of evidence point to D₃R as a valid therapeutic target for the treatment of several neuropsychiatric disorders including schizophrenia. In the present study, we tested the hypothesis that buspirone, behaving as dopamine D₃R antagonist, may have antipsychotic-like activity.

Materials and Methods: Effects of acute administration of buspirone was assessed on a wide-range of schizophrenia-relevant abnormalities induced by a single administration of the non-competitive NMDAR antagonist MK-801, in both wild-type mice (WT) and D₃R-null mutant mice (D₃R^-/-).

Results: Buspirone (3 mg⋅kg^-1, i.p.) was devoid of cataleptogenic activity in itself, but resulted effective in counteracting disruption of prepulse inhibition (PPI), hyperlocomotion and deficit of temporal order recognition memory (TOR) induced by MK-801 (0.1 mg⋅kg^-1, i.p.) in WT mice. Conversely, in D₃R^-/- mice, buspirone was ineffective in preventing MK-801-induced TOR deficit and it was only partially effective in blocking MK-801-stimulated hyperlocomotion.

Conclusion: Taken together, these results indicate, for the first time, that buspirone, might be a potential therapeutic medication for the treatment of schizophrenia. In particular, buspirone, through its D₃R antagonist activity, may be a useful tool for improving the treatment of cognitive deficits in schizophrenia that still represents an unmet need of this disease.

The Korean Version of the Schizophrenia Cognition Rating Scale: Reliability and Validity

OBJECTIVE

This study's aim was to develop and standardize a Korean version (SCoRS-K) of the Schizophrenia Cognition Rating Scale (SCoRS), which is used to evaluate the degree of cognitive dysfunction affecting the everyday functioning of people with schizophrenia.

METHODS

Eighty-four schizophrenia patients with stable symptoms who were receiving outpatient treatment and rehabilitation therapy, and 29 demographically matched non-patient controls, participated in the study. Demographic data were collected, and clinical symptoms, cognitive function, and social function were evaluated to verify SCoRS-K's reliability and validity. Clinical symptoms were evaluated using the Positive and Negative Syndrome Scale and the Clinical Global Impression-Schizophrenia Scale. Cognitive function was evaluated using a short form of the Korean Wechsler Adult Intelligence Scale and the Wisconsin Card Sorting Test (WCST). Social function was evaluated using the Social and Occupational Functioning Assessment Scale, the Schizophrenia Quality of Life Scale, and the Social Functioning Scale.

RESULTS

Data analysis demonstrated SCoRS-K's statistically significant reliability and validity. SCoRS-K has high internal consistency (Cronbach's alpha; patient 0.941, informant 0.905, interviewer 0.964); test-retest reliability [patient 0.428 (p=0.003), informant 0.502 (p<0.001), interviewer 0.602 (p<0.001); and global rating 0.642 (p<0.001)]. The mean scores of subjects were significantly higher than those of the controls (p<0.001), demonstrating SCoRS-K's discriminant validity. Significant correlations between the total scores and global rating score of SCoRS-K and those of the scales and tests listed above (except WCST) support SCoRS-K's concurrent validity.

CONCLUSION

SCoRS-K is a useful instrument for evaluating the degree of cognitive dysfunction in Korean schizophrenia patients.

Neurocognitive performance, psychopathology and social functioning in individuals at high risk for schizophrenia or psychotic bipolar disorder

INTRODUCTION

Although cognitive deficits are consistent endophenotypes of schizophrenia and bipolar disorder, findings in psychotic bipolar disorder (BDP) are inconsistent. In this study we compared adult unaffected first-degree relatives of schizophrenia and BDP patients on cognition, psychopathology, social functioning and quality of life.

METHODS

Sixty-six unaffected first-degree relatives of schizophrenia patients (SUnR), 36 unaffected first-degree relatives of BDP patients (BDPUnR) and 102 controls participated in the study. Between-group differences were examined and Discriminant Function Analysis (DFA) predicted group membership.

RESULTS

Visual memory, control inhibition, working memory, cognitive flexibility and abstract reasoning were linearly impaired in the relatives' groups. Poorer verbal fluency and processing speed were evident only in the SUnR group. The SUnR group had higher depressive and somatization symptoms while the BDPUnR group had higher anxiety and lower social functioning compared with the controls. Individuals with superior cognition were more likely to be classified as controls; those with higher social functioning, prolonged processing speed and lower anxiety were more likely to be classified as SUnR.

LIMITATIONS

The relatives' sample is quite heterogeneous; the effects of genetic or environmental risk-factors were not examined.

CONCLUSIONS

Cognitive functions mediated by a fronto-parietal network, show linear impairments in unaffected relatives of BDP and schizophrenia patients; processing speed and verbal fluency impairments were evident only in schizophrenia relatives. Self-perceived symptomatology and social functioning also differ between schizophrenia and BDP relatives. The continuum seen in patients in several indices was also seen in the cognitive impairments in unaffected relatives of schizophrenia and BDP patients.

Predictive value of premorbid IQ, negative symptoms, and age for cognitive and social functions in Japanese patients with schizophrenia: A study using the Japanese version of the Brief Assessment of Cognition in Schizophrenia

Enduring cognitive impairment in patients with schizophrenia represents a global health burden. The Japanese-language version of the Brief Assessment of Cognition in Schizophrenia (BACS) and the Japanese Adult Reading Test were administered to 288 patients with chronic schizophrenia and 308 unrelated healthy control subjects. The Japanese version of self-reported Social Functioning Scale (SFS) was administered to a subpopulation of 157 patients with schizophrenia. In patients with schizophrenia, premorbid IQ and age were significantly related to most of the BACS subdomains, composite score, and intra-individual variability of BACS subdomains, whereas negative symptoms were significantly related to all BACS indices. Dosages of the first-generation antipsychotics had a significant negative impact on Tower of London task and intra-individual variability of BACS subdomains. The relationship of symbol coding with age was significantly lower in patients than in healthy control subjects. Multiple regression analysis revealed that negative symptoms were significantly negatively related to the total SFS scale, whereas better performance of token motor task was associated with higher total SFS. The present study revealed the role of premorbid IQ, age, and negative symptoms in predicting cognitive performance, and the significant correlation of negative symptoms and token motor task with social function in patients with schizophrenia.

Impaired hippocampal-dependent memory and reduced parvalbumin-positive interneurons in a ketamine mouse model of schizophrenia

The hippocampus of patients with schizophrenia displays aberrant excess neuronal activity which affects cognitive function. Animal models of the illness have recapitulated the overactivity in the hippocampus, with a corresponding regionally localized reduction of inhibitory interneurons, consistent with that observed in patients. To better understand whether cognitive function is similarly affected in these models of hippocampal overactivity, we tested a ketamine mouse model of schizophrenia for cognitive performance in hippocampal- and medial prefrontal cortex (mPFC)-dependent tasks. We found that adult mice exposed to ketamine during adolescence were impaired on a trace fear conditioning protocol that relies on the integrity of the hippocampus. Conversely, the performance of the mice was normal on a delayed response task that is sensitive to mPFC damage. We confirmed that ketamine-exposed mice had reduced parvalbumin-positive interneurons in the hippocampus, specifically in the CA1, but not in the mPFC in keeping with the behavioral findings. These results strengthened the utility of the ketamine model for preclinical investigations of hippocampal overactivity in schizophrenia.

Anomalous self-experiences and their relationship with symptoms, neuro-cognition, and functioning in at-risk adolescents and young adults

Empirical and theoretical studies support the notion that anomalous self-experience (ASE) may constitute a phenotypic aspect of vulnerability to schizophrenia, but there are no studies examining the relationship of ASE with other clinical risk factors in a sample of ultra-high risk (UHR) subjects. The aim of the present study was to explore the relationship between ASE, prodromal symptoms, neurocognition, and global functioning in a sample of 45 UHR adolescents and young adults (age range 15-25years) at first contact with Public Mental Health Services. Prodromal symptoms and global functioning were assessed through the SIPS interview. ASE was evaluated through the Examination of Anomalous Self-Experience (EASE); for neurocognition, we utilized a battery of tests examining seven cognitive domains as recommended by the Measurement And Treatment Research to Improve Cognition in Schizophrenia. In the UHR group, higher levels in two domains of the EASE (stream of consciousness and self-awareness) were found in comparison with help-seeking subjects. Correlational analysis corrected for possible confounding variables showed a strong association (p>0.001) between higher EASE scores and global functioning. A principal factor analysis with Varimax rotation yielded a two-factor solution, jointly accounting for 70.58% of the total variance in the UHR sample. The first factor was comprised of SOPS domains, while the second was comprised of EASE-total, EASE-10, and GAF variables. Our findings provide support for the notion that disorders of self-experience are present early in schizophrenia and are related to global functioning. As such, they may constitute a potential marker of risk supplementing the UHR approach.

White matter microstructure in ultra-high risk and first episode schizophrenia: A prospective study

There is increasing evidence of white matter (WM) pathology in schizophrenia, but its role at the very early stage of the disorder remains unclear. In an exploration of WM microstructure in ultra-high risk (UHR) subjects and first episode schizophrenia (FES), 34 FES, 27 UHR and 26 healthy control (HC) subjects underwent a magnetic resonance imaging (MRI) tract based spatial statistics (TBSS) investigation. Whole brain fractional anisotropy (FA), mean diffusivity (MD), radial (RD) and axial diffusivity (AD) values were extracted. UHR subjects who later developed psychosis showed lower FA compared with HC in the corpus callosum (CC), the left superior and inferior longitudinal fasciculus, the left inferior fronto-occipital fasciculs (IFO), and the forceps; RD was significantly higher in the CC, the forceps, the anterior thalamic radiation bilaterally, and the cingulum bundle. FES, compared to HC, showed a significant FA reduction of the CC, the superior and inferior longitudinal fasciculi bilaterally, the IFO bilaterally, the corona radiate bilaterally, and the forceps; while RD was found to be significantly increased in the left superior longitudinal fasciculus. UHR who later developed psychosis had WM abnormalities affecting brain pathways that are crucial for intra- and inter-hemispheric connections.

Social Cognition in Individuals at Ultra-High Risk for Psychosis: A Meta-Analysis

Objective

Treatment in the ultra-high risk stage for a psychotic episode is critical to the course of symptoms. Markers for the development of psychosis have been studied, to optimize the detection of people at risk of psychosis. One possible marker for the transition to psychosis is social cognition. To estimate effect sizes for social cognition based on a quantitative integration of the published evidence, we conducted a meta-analysis of social cognitive performance in people at ultra high risk (UHR).

Methods

A literature search (1970-July 2015) was performed in PubMed, PsychINFO, Medline, Embase, and ISI Web of Science, using the search terms ‘social cognition’, ‘theory of mind’, ‘emotion recognition’, ‘attributional style’, ‘social knowledge’, ‘social perception’, ‘empathy’, ‘at risk mental state’, ‘clinical high risk’, ‘psychosis prodrome’, and ‘ultra high risk’. The pooled effect size (Cohen’s D) and the effect sizes for each domain of social cognition were calculated. A random effects model with 95% confidence intervals was used.

Results

Seventeen studies were included in the analysis. The overall significant effect was of medium magnitude (d = 0.52, 95% Cl = 0.38–0.65). No moderator effects were found for age, gender and sample size. Sub-analyses demonstrated that individuals in the UHR phase show significant moderate deficits in affect recognition and affect discrimination in faces as well as in voices and in verbal Theory of Mind (TOM). Due to an insufficient amount of studies, we did not calculate an effect size for attributional bias and social perception/ knowledge. A majority of studies did not find a correlation between social cognition deficits and transition to psychosis, which may suggest that social cognition in general is not a useful marker for the development of psychosis. However some studies suggest the possible predictive value of verbal TOM and the recognition of specific emotions in faces for the transition into psychosis. More research is needed on these subjects.

Conclusion

The published literature indicates consistent general impairments in social cognition in people in the UHR phase, but only very specific impairments seem to predict transition to psychosis.

Effects of glutamate positive modulators on cognitive deficits in schizophrenia: a systematic review and meta-analysis of double-blind randomized controlled trials

Hypofunction of N-methyl-d-aspartate (NMDA) receptors has been proposed to have an important role in the cognitive impairments observed in schizophrenia. Although glutamate modulators may be effective in reversing such difficult-to-treat conditions, the results of individual studies thus far have been inconsistent. We conducted a systematic review and meta-analysis to examine whether glutamate positive modulators have beneficial effects on cognitive functions in patients with schizophrenia. A literature search was conducted to identify double-blind randomized placebo-controlled trials in schizophrenia or related disorders, using Embase, Medline, and PsycINFO (last search: February 2015). The effects of glutamate positive modulators on cognitive deficits were evaluated for overall cognitive function and eight cognitive domains by calculating standardized mean differences (SMDs) between active drugs and placebo added to antipsychotics. Seventeen studies (N=1391) were included. Glutamate positive modulators were not superior to placebo in terms of overall cognitive function (SMD=0.08, 95% confidence interval=-0.06 to 0.23) (11 studies, n=858) nor each of eight cognitive domains (SMDs=-0.03 to 0.11) (n=367-940) in this population. Subgroup analyses by diagnosis (schizophrenia only studies), concomitant antipsychotics, or pathway of drugs to enhance the glutamatergic neurotransmission (glycine allosteric site of NMDA receptors or α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors) suggested no procognitive effect of glutamate positive modulators. Further, no effect was found in individual compounds on cognition. In conclusion, glutamate positive modulators may not be effective in reversing overall cognitive impairments in patients with schizophrenia as adjunctive therapies.

Attention-deficit/hyperactivity disorder, methylphenidate use and the risk of developing schizophrenia spectrum disorders: A nationwide population-based study in Taiwan

This study estimated the risk of developing psychotic disorders by comparing children with ADHD to non-ADHD controls, and to examine whether methylphenidate (MPH) treatment influences the risks of psychotic disorders. A nationwide cohort of patients who were newly diagnosed with ADHD (n=73,049) and age- and gender-matched controls (n=73,049) were selected from Taiwan's National Health Insurance database from January 2000 to December 2011. All participants were observed until December 31, 2011. Cox regression models were used to estimate the effects of ADHD diagnosis and MPH use on subsequent outcomes. Having a diagnosis of any psychotic disorder and of schizophrenia were set as two different outcomes and were analyzed separately. Compared to the control group, the ADHD group showed significantly increased risk of developing any psychotic disorder (adjusted hazard ratio [aHR], 5.20; 95% confidence interval [CI], 4.30-6.30) and schizophrenia (aHR, 4.65; 95% CI, 3.59-6.04). Compared to ADHD patients without psychosis, patients with ADHD who developed psychosis had significantly older age at first diagnosis of ADHD (9.4±3.3years vs. 10.6±4.0years). Among patients with ADHD, MPH use significantly increased the risk of developing any psychotic disorder (aHR, 1.20; 95% CI, 1.04-1.40), but did not increase the risk of developing schizophrenia (aHR, 1.16; 95% CI, 0.94-1.42). The results indicated that previous diagnoses of ADHD are a powerful indicator of developing psychotic disorders. Nevertheless, the specific mechanisms of the relationships between ADHD, MPH use and psychotic disorders need further elucidation in future clinical studies.

Metacognition-augmented cognitive remediation training reduces jumping to conclusions and overconfidence but not neurocognitive deficits in psychosis

The majority of patients with schizophrenia display neurocognitive deficits (e.g., memory impairment) as well as inflated cognitive biases (e.g., jumping to conclusions). Both cognitive domains are implicated in the pathogenesis of the disorder and are known to compromise functional outcome. At present, there is a dearth of effective treatment options. A total of 90 patients with schizophrenia were recruited online (a diagnosis of schizophrenia had been confirmed in a large subgroup during a previous hospital admission). Subsequent to a baseline assessment encompassing psychopathology, self-reported cognition as well as objective memory and reasoning tests, patients were randomized to one of three conditions: standard cognitive remediation (mybraintraining), metacognition-augmented cognition remediation (CR) condition (variant of mybraintraining which encouraged patients to reduce speed of decision-making and attenuate response confidence when participants made high-confidence judgements and hasty incorrect decisions) and a waitlist control group. Patients were retested after 6 weeks and again 3 months after the second assessment. Groups did not differ on psychopathology and neurocognitive parameters at any timepoint. However, at follow-up the metacognitive-augmented CR group displayed a significant reduction on jumping to conclusions and overconfidence. Treatment adherence correlated with a reduction of depression; gains in the training exercises from the standard mybraintraining condition were correlated with improved objective memory performance. The study suggests that metacognition-augmented CR may ameliorate cognitive biases but not neurocognition. The study ties in well with prior research showing that neurocognitive dysfunctions are rather resistant to change; the failure to detect significant improvement of CR or metacognition-augmented CR on psychopathology and neurocognition over time may partly be attributed to a number of methodological limitations of our study (low psychopathology and chronicity of participants, low “dosage,” narrow range of tests, self-report psychopathology scales).