Performance on a contour integration task as a function of contour shape in schizophrenia and controls

Contour Integration (CI) is the ability to integrate elemental features into objects and is a basic visual process essential for object perception and recognition, and for functioning in visual environments. It is now well documented that people with schizophrenia (SZ), in addition to having cognitive impairments, also have several visual perceptual deficits, including in CI. Here, we retrospectively characterize the performance of both SZ and neurotypical individuals (NT) on a series of contour shapes, made up of Gabor elements, that varied in terms of closure and curvature. Participants in both groups performed a CI training task that included 7 different families of shapes (Lines, Ellipse, Blobs, Squiggles, Spiral, Circle and Letters) for up to 40 sessions. Two parameters were manipulated in the training task: Orientation Jitter (OJ, i.e., orientation deviations of individual Gabor elements from ideal for each shape) and Inducer Number (IN, i.e., number of Gabor elements defining the shape). Results show that both OJ and IN thresholds significantly differed between the groups, with higher (OJ) and lower (IN) thresholds observed in the controls. Furthermore, we found significant effects as a function of the contour shapes, with differences between groups emerging with contours that were considered more complex, e.g., due to having a higher degree of curvature (Blobs, Spiral, Letters). These data can inform future work that aims to characterize visual integration impairments in schizophrenia.

Association between adverse childhood experiences and suicidal behavior in schizophrenia spectrum disorders: A systematic review and meta-analysis

Assessing and managing suicide behaviors is highly relevant to individuals with schizophrenia spectrum disorders. Our study aims to assess the association between adverse childhood experiences and suicidal behaviors in individuals with schizophrenia spectrum disorders. We included observational studies comparing the probability of suicide behaviors in adults with schizophrenia spectrum disorders exposed and unexposed to adverse childhood experiences. Odds ratio estimates were obtained by pooling data using a random-effects pairwise meta-analysis. Standardized criteria were used to assess the strength of the association of the pooled estimate. We found 21 eligible studies reporting outcomes for 6257 individuals from 11 countries. The primary outcome revealed an association between any suicidal behavior and adverse childhood experiences, which resulted "highly suggestive" according to validated Umbrella Criteria. Similarly, a positive association was confirmed for suicidal ideation and suicide attempt and for any subtype of adverse childhood experience. This meta-analysis showed that exposure to adverse childhood experiences strongly increases the probability of suicide behaviors in people with schizophrenia spectrum disorders.

Computerized cognitive and social cognition training in schizophrenia for impulsive aggression

BACKGROUND

Schizophrenia is associated with an elevated risk for impulsive aggression for which there are few psychosocial treatment options. Neurocognitive and social cognitive deficits have been associated with aggression with social cognitive deficits seemingly a more proximal contributor. The current study examined the effects of combining cognitive and social cognition treatment on impulsive aggression among inpatients with chronic schizophrenia and schizoaffective disorder and a history of aggression compared to cognitive remediation treatment alone.

METHODS

The two-center study randomized 130 participants to receive 36 sessions of either a combination of cognitive remediation and social cognition treatment or cognitive remediation plus a computer-based control. Participants had at least one aggressive incident within the past year or a Life History of Aggression (LHA) score of 5 or more. Participants completed measures of neurocognition, social cognition, symptom severity, and aggression at baseline and endpoint.

RESULTS

Study participants were mostly male (84.5 %), had a mean age 34.9 years, and 11.5 years of education. Both Cognitive Remediation Training (CRT) plus Social Cognition Training (SCT) and CRT plus control groups were associated with significant reductions in aggression measures with no group differences except on a block of the Taylor Aggression Paradigm (TAP), a behavioral task of aggression which favored the CRT plus SCT group. Both groups showed significant improvements in neurocognition and social cognition measures with CRT plus SCT being associated with greater improvements.

CONCLUSION

CRT proved to be an effective non-pharmacological treatment in reducing impulsive aggression in schizophrenia inpatient participants with a history of aggressive episodes. The addition of social cognitive training did not enhance this anti-aggression treatment effect but did augment the CRT effect on cognitive functions, on emotion recognition and on mentalizing capacity of our participants.

Five negative symptom domains are differentially associated with resting state amplitude of low frequency fluctuations in Schizophrenia

This study examined associations between resting-state amplitude of low frequency fluctuations (ALFF) and negative symptoms represented by total scores, second-order dimension (motivation and pleasure, expressivity), and first-order domain (anhedonia, avolition, asociality, alogia, blunted affect) factor scores in schizophrenia (n = 57). Total negative symptom scores showed positive associations with ALFF in temporal and frontal brain regions. Negative symptom domain scores showed predominantly stronger associations with regional ALFF compared to total scores, suggesting domain scores may better map to neural signatures than total scores. Improving our understanding of the neuropathology underlying negative symptoms may aid in addressing this unmet therapeutic need in schizophrenia.

Latent structure of cognitive tests is invariant in men and women with schizophrenia

Studies comparing the cognitive functioning of men and women with schizophrenia have produced conflicting results which could arise from sex-based differences in the latent structure of cognitive abilities. The current study used multigroup confirmatory factor analysis to examine invariance in latent structure of cognitive abilities to between men and women with schizophrenia. Confirmatory factor analysis of an initial neurocognitive assessment (men n = 612, women n = 201) and cross-validation using second assessment (men n = 549, women n = 198) demonstrated that a bifactor seven-factor model fit the data best for both men and women. Invariance analyses further indicated this model was invariant across men and women at both assessments. Group comparisons indicated women had significantly higher scores for Semantic Memory, Verbal Memory, and General Cognitive factors, whereas men exhibited better performance on the Vigilance factor. Results indicate that cognition in SZ is characterized by both a general cognitive factor and specific domains for both men and women. Invariance analysis provides evidence that cognitive differences between men and women do not result from sex-based differences in the latent structure of cognitive abilities. Current results also indicate small but statistically significant neurocognitive differences between men and women with schizophrenia.

Two Factors, Five Factors, or Both? External Validation Studies of Negative Symptom Dimensions in Schizophrenia

OBJECTIVES

Negative symptom studies frequently use single composite scores as indicators of symptom severity and as primary endpoints in clinical trials. Factor analytic and external validation studies do not support this practice but rather suggest a multidimensional construct. The current study used structural equation modeling (SEM) to compare competing dimensional models of negative symptoms to determine the number of latent dimensions that best capture variance in biological, psychological, and clinical variables known to have associations with negative symptoms.

METHODS

Three independent studies (total n = 632) compared unidimensional, two-factor, five-factor, and hierarchical conceptualizations of negative symptoms in relation to cognition, psychopathology, and community functioning (Study 1); trait emotional experience and defeatist performance beliefs (Study 2); and glutamate and gamma-aminobutyric acid levels in the anterior cingulate cortex quantified using proton magnetic resonance spectroscopy (Study 3).

RESULTS

SEM favored the five-factor and hierarchical models over the unidimensional and two-factor models regardless of the negative symptom measure or external validator. The five dimensions-anhedonia, asociality, avolition, blunted affect, and alogia-proved vital either as stand-alone domains or as first-order domains influenced by second-order dimensions-motivation and pleasure and emotional expression. The two broader dimensions sometimes masked important associations unique to the five narrower domains. Avolition, anhedonia, and blunted affect showed the most domain-specific associations with external variables across study samples.

CONCLUSIONS

Five domains and a hierarchical model reflect the optimal conceptualization of negative symptoms in relation to external variables. Clinical trials should consider using the two dimensions as primary endpoints and the five domains as secondary endpoints.

ENIGMA + COINSTAC: Improving Findability, Accessibility, Interoperability, and Re-usability

The FAIR principles, as applied to clinical and neuroimaging data, reflect the goal of making research products Findable, Accessible, Interoperable, and Reusable. The use of the Collaborative Informatics and Neuroimaging Suite Toolkit for Anonymized Computation (COINSTAC) platform in the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) consortium combines the technological approach of decentralized analyses with the sociological approach of sharing data. In addition, ENIGMA + COINSTAC provides a platform to facilitate the use of machine-actionable data objects. We first present how ENIGMA and COINSTAC support the FAIR principles, and then showcase their integration with a decentralized meta-analysis of sex differences in negative symptom severity in schizophrenia, and finally present ongoing activities and plans to advance FAIR principles in ENIGMA + COINSTAC. ENIGMA and COINSTAC currently represent efforts toward improved Access, Interoperability, and Reusability. We highlight additional improvements needed in these areas, as well as future connections to other resources for expanded Findability.

A Meta-Analysis of Brain-Derived Neurotrophic Factor Effects on Brain Volume in Schizophrenia: Genotype and Serum Levels

AIM

The Val66Met single-nucleotide polymorphism (SNP) on the BDNF gene has established pleiotropic effects on schizophrenia incidence and morphologic alterations in the illness. The effects of brain-derived neurotrophic factor (BDNF) on brain volume measurements are however mixed seeming to be less established for most brain regions. The current meta-analytic review examined (1) the association of the Val66Met SNP and brain volume alterations in schizophrenia by comparing Met allele carriers to Val/Val homozygotes and (2) the association of serum BDNF with brain volume measurements.

METHOD

Studies included in the meta-analyses were identified through an electronic search of PubMed and PsycInfo (via EBSCO) for English language publications from January 2000 through December 2017. Included studies had conducted a genotyping procedure of Val66Met or obtained assays of serum BDNF and obtained brain volume data in patients with psychotic disorders. Nonhuman studies were excluded.

RESULTS

Study 1 which included 52 comparisons of Met carriers and Val/Val homozygotes found evidence of lower right and left hippocampal volumes among Met allele carriers with schizophrenia. Frontal measurements, while also lower among Met carriers, did not achieve statistical significance. Study 2 which included 7 examinations of the correlation between serum BDNF and brain volume found significant associations between serum BDNF levels and right and left hippocampal volume with lower BDNF corresponding to lower volumes.

DISCUSSION

The meta-analyses provided evidence of associations between brain volume alterations in schizophrenia and variations on the Val66Met SNP and serum BDNF. Given the limited number of studies, it remains unclear if BDNF effects are global or regionally specific.

A-96 Stability of ImPACT’s Latent Structure from Baseline to Post Concussion Assessment

Objective

ImPACT is commonly used for sport-concussion management. Baseline and post-concussion tests serve as within-athlete comparisons for return-to-play decision-making. Previous literature has questioned whether ImPACT’s five composites accurately represent the internal structure of its cognitive scores. A recent alternative four-factor structure has strong confirmatory evidence for baseline scores (Maietta et al., doi:10.1037/pas0001014). The present study examined the stability of these constructs post-concussion.

Method

The current study utilized a case-matched design (age, sex, sport category) to select a sample of 3560 high school athletes’ baseline (n = 1780) and post-concussion (n = 1780) assessments. Multi-group CFA of first-order, hierarchical, and bifactor models was conducted to assess measurement invariance (configural, metric, scalar, and residual invariance) between baseline and post-concussion samples. Change in comparative fit indices was interpreted as the primary indicator of model invariance.

Results

ImPACT’s five composite structure, as well as the hierarchical and bifactor models, exhibited inadequate fit to the baseline and post-concussion data. The four-factor model demonstrated superior fit in the baseline sample and good fit in the post-concussion sample. The four-factor structure demonstrated invariance across injury status (baseline to post-concussion).

Conclusion

Given that ImPACT’s scores are used for return-to-play decision-making, it is important that they are psychometrically sound. Recent literature suggests that ImPACT’s five composites are not an adequate representation of the cognitive constructs. Findings support validity of the four-factor structure despite injury status, suggesting these cognitive constructs are assessable at both pre- and post-concussion. Additional research is needed to determine implications of these findings for tracking cognitive change following sport-related concussion and making return-to-play decisions.

Confirmatory factor analysis of imPACT cognitive tests in high school athletes

ImPACT is the most commonly utilized computerized neurocognitive assessment for the clinical management of sport concussion. The cognitive composite scores that ImPACT currently reports include Verbal Memory, Visual Memory, Visual Motor Speed, Reaction Time, and Impulse Control. However, exploratory factor analytic studies report that two or more factors may better represent ImPACT's latent structure, suggesting that the current cognitive composites may not adequately represent the cognitive constructs ImPACT assesses. The latent structure of ImPACT cognitive baseline scores was examined using exploratory (EFA) and confirmatory factor analysis (CFA) of valid baseline ImPACT scores for 36,091 high school athletes. These athletes were randomly divided into two samples. The first sample was a calibration sample used for EFA and the second sample was a cross-validation sample used for CFA to estimate the best model identified in the calibration phase, along with other models that were reported in the literature or based on theoretical considerations, including hierarchical and bifactor models. EFA identified a first-order four-factor solution consisting of Visual Memory, Visual Reaction Time, Verbal Memory, and Working Memory constructs. CFA indicated that this four-factor model provided superior fit for the data, while the current five-composite structure of ImPACT provided a poor fit for the data. The latent constructs identified in this study using CFA do not map well onto the composite scores that are currently used to interpret ImPACT performance. Future research should investigate whether interpretation of ImPACT based on the constructs identified here will be more useful for clinical decision making than current approaches. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Bifactor model of cognition in schizophrenia: Evidence for general and specific abilities

BACKGROUND

Despite extensive study of cognition in schizophrenia, it remains unclear as to whether cognitive deficits and their latent structure are best characterized as reflecting a generalized deficit, specific deficits, or some combination of general and specific constructs.

METHOD

To clarify latent structure of cognitive abilities, confirmatory factor analysis was used to examine the latent structure of cognitive data collected for the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) for Schizophrenia study. Baseline assessment data (n = 813) were randomly divided into calibration (n = 413) and cross-validation samples (n = 400). To examine whether generalized or specific deficit models provided better explanation of the data, we estimated first-order, hierarchical, and bifactor models.

RESULTS

A bifactor model with seven specific factors and one general factor provided the best fit to the data for both the calibration and cross-validation samples.

CONCLUSIONS

These findings lend support for a replicable bifactor model of cognition in schizophrenia, characterized by both a general cognitive factor and specific domains. This suggests that cognitive deficits in schizophrenia might be best understood by separate general and specific contributions.

Validation of the traditional script Chinese version of the brief negative symptom scale

Negative symptoms are a core feature of schizophrenia and account for much of the long-term morbidity and poor functional outcome of people with schizophrenia. The Brief Negative Symptom Scale (BNSS) was developed to address the main limitations of the existing scales for the assessment of negative symptoms. The BNSS has been translated into Italian, Spanish, German, Turkish and simplified Chinese versions with excellent psychometric properties. In this study, a Chinese (traditional script) version of the Brief Negative Symptom Scale (C-BNSS) was developed and validated to facilitate future research on the Chinese population in Hong Kong. Psychometric properties were examined in 149 individuals with schizophrenia. The C-BNSS showed excellent internal consistency (α = 0.96), high inter-rater reliability (intra-class correlation = 0.98), and high test-retest reliability (Spearman's r = 0.96). Convergent validity was supported by high correlations between C-BNSS total score and subscales with the Scale for Assessment of Negative Symptoms (SANS), Negative Symptom subscale of the Positive and Negative Syndrome Scale (PANSS), and Global Assessment of Functioning (GAF) score. Discriminant validity was supported by low correlations between the C-BNSS total score and the PANSS positive subscale, Calgary Depression Scale, and Simpson-Angus Scale for extrapyramidal symptoms. The C-BNSS showed a five- factor structure on Confirmatory Factor Analysis (CFA), confirming findings of previous studies. Findings indicate that the C-BNSS demonstrates excellent psychometric properties, which are comparable to the original English version. It is a promising instrument for use in clinical trials as well as in clinical practice.

The Latent Structure of Negative Symptoms in Individuals With Attenuated Psychosis Syndrome and Early Psychosis: Support for the 5 Consensus Domains

Negative symptoms are prevalent in the prodromal and first-episode phases of psychosis and highly predictive of poor clinical outcomes (eg, liability for conversion and functioning). However, the latent structure of negative symptoms is unclear in the early phases of illness. Determining the latent structure of negative symptoms in early psychosis (EP) is of critical importance for early identification, prevention, and treatment efforts. In the current study, confirmatory factor analysis was used to evaluate latent structure in relation to 4 theoretically derived models: 1. a 1-factor model, 2. a 2-factor model with expression (EXP) and motivation and pleasure (MAP) factors, 3. a 5-factor model with separate factors for the 5 National Institute of Mental Health (NIMH) consensus development conference domains (blunted affect, alogia, anhedonia, avolition, and asociality), and 4. a hierarchical model with 2 second-order factors reflecting EXP and MAP, as well as 5 first-order factors reflecting the 5 consensus domains. Participants included 164 individuals at clinical high risk (CHR) who met the criteria for a prodromal syndrome and 377 EP patients who were rated on the Brief Negative Symptom Scale. Results indicated that the 1- and 2-factor models provided poor fit for the data. The 5-factor and hierarchical models provided excellent fit, with the 5-factor model outperforming the hierarchical model. These findings suggest that similar to the chronic phase of schizophrenia, the latent structure of negative symptom is best conceptualized in relation to the 5 consensus domains in the CHR and EP populations. Implications for early identification, prevention, and treatment are discussed.

The latent structure of depressive symptoms across clinical high risk and chronic phases of psychotic illness

Depressive symptoms are highly prevalent in psychotic populations and result in significant functional impairment. Limited knowledge of whether depressive symptoms are invariant across stages of illness curtails our ability to understand how these relate to illness progression. Clarifying the latent structure of depressive symptoms across stages of illness progression would aid etiological conceptualizations and preventive models. In the present study, one-factor (including all items) and two-factor (depression/hopelessness and guilt/self-depreciation) solutions were specified through confirmatory factor analysis (CFA). Measurement invariance analyses were undertaken across schizophrenia (SCZ; n = 312) and clinical high-risk (CHR; n = 175) groups to estimate whether the same construct is being measured across groups. Clinical correlates of the factors were examined. Results indicated that CHR individuals had a greater proportion of mood disorder diagnoses. Metric invariance held for the one-factor solution, and scalar invariance held for the two-factor solution. Notably, negative symptoms did not correlate with depressive symptoms in the SCZ group, though strong correlations were observed in CHR individuals. Positive symptoms were comparably associated with depressive symptoms in both groups. Results suggest depressive symptoms are more prevalent in CHR individuals. Targeting these symptoms may aid future efforts to identify risk of conversion. Further, some depressive symptoms may be systematically more endorsed in CHR individuals. Separating into depression/hopelessness and guilt/self-depreciation scores may aid comparability across stages of illness progression, though this issue deserves careful attention and future study.

Sleep health of healthcare workers in Kano, Nigeria

BACKGROUND

The relevance of sleep in the life of a human being cannot be overemphasized in terms of physical and mental well-being. Among several factors that can affect the sleep health of an individual occupation have been found to play a prominent role. The literature is still scanty with regard to sleep studies in our environment.

AIM

This study aims to assess the sleep health of tertiary healthcare workers in Kano Nigeria and find, if any, its determining or related factors.

MATERIAL AND METHODS

This study was cross-sectional questionnaire-based survey and involved all consenting staff members of Aminu Kano Teaching Hospital, Kano, Nigeria. The Pittsburgh Sleep Quality Index Questionnaire was used to assess the sleep health of the participants.

RESULTS

The participants' ages ranged from 18 to 65 years and have a mean age of 38.94 ± 8.07 years. There were 119 (74.4%) males and 41 (25.4%) females with a M:F ratio of 3:1 (χ2 = 19.415; P = 0.000). Among the 155 participants who completed all the aspects of the Pittsburgh Sleep Quality Index questionnaires, the overall sleep quality of the study population was found to be significantly poor [good sleepers = 71 (45.8%), poor sleepers = 84 (54.2%), χ2 = 116.4; P = 0.000]. Considering the various occupational groups working in the hospital, poor sleep was commonest among the nurses 35 (42.7%). Furthermore, among the nurses, poor sleep was significantly commoner in those on shift work 27 (77.1%) than those not on shift work 8 (22.9%); χ2 = 36.2; P = 0.000. Multivariate logistic regression analysis showed that age, sex, and duration in service were not significant predictors of poor sleep quality among the participants [odds ratio (OR) = 1.013, 95% confidence interest (CI) = 0.948-1.084, P = 0.698; OR = 0.691, 95% CI = 0.293-1.631, P = 0.399; and OR = 0.993, 95% CI = 0.932-1.058 P = 0.840, respectively).

CONCLUSIONS

Our study found that a significant proportion of healthcare workers and particularly nurses had poor sleep quality. Also, age, sex, and duration in service were not significant predictors of poor sleep quality among the participants.

Cross-cultural Validation of the 5-Factor Structure of Negative Symptoms in Schizophrenia

OBJECTIVE

Negative symptoms are currently viewed as having a 2-dimensional structure, with factors reflecting diminished expression (EXP) and motivation and pleasure (MAP). However, several factor-analytic studies suggest that the consensus around a 2-dimensional model is premature. The current study investigated and cross-culturally validated the factorial structure of BNSS-rated negative symptoms across a range of cultures and languages.

METHOD

Participants included individuals diagnosed with a psychotic disorder who had been rated on the Brief Negative Symptom Scale (BNSS) from 5 cross-cultural samples, with a total N = 1691. First, exploratory factor analysis was used to extract up to 6 factors from the data. Next, confirmatory factor analysis evaluated the fit of 5 models: (1) a 1-factor model, 2) a 2-factor model with factors of MAP and EXP, 3) a 3-factor model with inner world, external, and alogia factors; 4) a 5-factor model with separate factors for blunted affect, alogia, anhedonia, avolition, and asociality, and 5) a hierarchical model with 2 second-order factors reflecting EXP and MAP, as well as 5 first-order factors reflecting the 5 aforementioned domains.

RESULTS

Models with 4 factors or less were mediocre fits to the data. The 5-factor, 6-factor, and the hierarchical second-order 5-factor models provided excellent fit with an edge to the 5-factor model. The 5-factor structure demonstrated invariance across study samples.

CONCLUSIONS

Findings support the validity of the 5-factor structure of BNSS-rated negative symptoms across diverse cultures and languages. These findings have important implications for the diagnosis, assessment, and treatment of negative symptoms.

The Latent Structure of Negative Symptoms in Schizophrenia

IMPORTANCE

Negative symptoms are associated with a range of poor clinical outcomes, and currently available treatments generally do not produce a clinically meaningful response. Limited treatment progress may be owing in part to poor clarity regarding latent structure. Prior studies have inferred latent structure using exploratory factor analysis, which has led to the conclusion that there are 2 dimensions reflecting motivation and pleasure (MAP) and diminished expressivity (EXP) factors. However, whether these conclusions are statistically justified remains unclear because exploratory factor analysis does not test latent structure. Confirmatory factor analysis (CFA) is needed to test competing models regarding the latent structure of a construct.

OBJECTIVE

To evaluate the fit of 4 models of the latent structure of negative symptoms in schizophrenia using CFA.

DESIGN, SETTING, AND PARTICIPANTS

Three cross-sectional studies were conducted on outpatients with schizophrenia who were rated on the 3 most conceptually contemporary measures: Scale for the Assessment of Negative Symptoms (SANS), Brief Negative Symptom Scale (BNSS), and Clinical Assessment Interview for Negative Symptoms (CAINS). Confirmatory factor analysis evaluated the following 4 models: (1) a 1-factor model; (2) a 2-factor model with EXP and MAP factors; (3) a 5-factor model with separate factors for the 5 domains of the National Institute of Mental Health consensus development conference (blunted affect, alogia, anhedonia, avolition, and asociality); and (4) a hierarchical model with 2 second-order factors reflecting EXP and MAP and 5 first-order factors reflecting the 5 consensus domains.

MAIN OUTCOMES AND MEASURES

Outcomes included CFA model fit statistics derived from symptom severity scores on the SANS, BNSS, and CAINS.

RESULTS

The study population included 860 outpatients with schizophrenia (68.0% male; mean [SD] age, 43.0 [11.4] years). Confirmatory factor analysis was conducted on each scale, including 268 patients for the SANS, 192 for the BNSS, and 400 for the CAINS. The 1- and 2-factor models provided poor fit for the SANS, BNSS, and CAINS as indicated by comparative fit indexes (CFIs) and Tucker Lewis indexes (TLIs) less than 0.950, RMSEAs that exceeded the 0.080 threshold, and WRMRs greater than 1.00. The 5-factor and hierarchical models provided excellent fit, with the 5-factor model being more parsimonious. The CFIs and TLIs met the 0.95 threshold and the 1.00 threshold for both factor models with all 3 measures. Interestingly, the RMSEAs for the 5-factor model and the hierarchical model fell under the 0.08 threshold for the BNSS and the CAINS but not the SANS.

CONCLUSIONS AND RELEVANCE

These findings suggest that the recent trend toward conceptualizing the latent structure of negative symptoms as 2 distinct dimensions does not adequately capture the complexity of the construct. The latent structure of negative symptoms is best conceptualized in relation to the 5 consensus domains. Implications for identifying pathophysiological mechanisms and targeted treatments are discussed.

Childhood Physical and Sexual Abuse Predicts Suicide Risk in a Large Cohort of Veterans

Objective

To examine whether childhood physical and sexual abuse is a significant predictor of suicide risk in veterans.

Methods

This study was a retrospective chart review of 4,709 patients admitted to a psychiatric ward (August 2004 through July 2014) at the Atlanta Veterans Affairs Medical Center (VAMC). Sociodemographic and clinical data and history of childhood (aged ≤ 18 years) physical and sexual abuse were obtained from the patients' electronic health records. Suicide risk data of patients who attempted and completed suicide were obtained from the Atlanta VAMC suicide high-risk team. Binary logistic regressions with maximum likelihood estimation method were used to examine the association of demographic (age, sex, marital status, race, service) and clinical (psychiatric diagnoses, number of hospital admissions, and length of stay) variables and childhood physical and sexual abuse and type with suicide behavior.

Results

The combination of childhood physical and sexual abuse, number of admissions to a psychiatric inpatient unit, and major depressive disorder (MDD) were the best predictors of enhanced suicide risk (P < .001). This combination accounted for 9.9% variance in suicide risk and correctly classified 83% of cases into respective suicide versus nonsuicide risk groups. Additional significant predictors were bipolar disorder (P < .001) and cocaine use disorder (P = .02). Surprisingly, diagnosis of schizophrenia predicted a reduced risk.

Conclusions

To our knowledge, this study is the first to shed light on the interaction of childhood physical and sexual abuse and suicide risk in a large cohort of veterans. In the final model, childhood physical and sexual abuse, number of psychiatric admissions, and MDD were the best predictors of increased suicide risk. Schizophrenia was a protective factor in this veteran cohort.

The brief negative symptom scale (BNSS): Sensitivity to treatment effects

The Brief Negative Symptom Scale (BNSS) grew out of a recommendation by the NIMH-sponsored Consensus Development Conference on Negative Symptoms that a scale based on contemporary concepts be developed. We assessed sensitivity to change of the BNSS in a trial of MIN-101, which showed efficacy for negative symptoms (PANSS pentagonal model) at daily doses of 32 and 64mg/day. Using mixed-effects model for repeated measures, we examined change in BNSS total score and in the BNSS factors of anhedonia/avolition/asociality (AAA), and expressivity (EXP). Compared to placebo, the 64mg group (N=83) showed a significant decrease in BNSS total score (effect size d [ES] 0.56, p<0.01) and both factor scores (AAA ES=0.48, EXP ES=0.46, p<0.02 for both). Patients in the trial had minimal depression and positive symptom scores; covarying for disorganization, positive symptoms, or anxiety/depression did not cause a meaningful change in the significance of the BNSS total or factor scores in this group. The 32mg group (N=78) did not differ significantly from placebo (N=83) on BNSS total score (ES=0.33, p<0.09), AAA (ES=0.25, p<0.20) or EXP (ES=0.30, p<0.12) scores. These results demonstrate the BNSS is sensitive to change.

Complement component 3a receptor deficiency attenuates chronic stress-induced monocyte infiltration and depressive-like behavior

Major depressive disorder (MDD) is one of the most common and debilitating neuropsychiatric illnesses. Accumulating evidence suggests a potential role of the immune system in the pathophysiology of MDD. The complement system represents one of the major effector mechanisms of the innate immune system, and plays a critical role in inflammation. However, the role of complement components in MDD is not well understood. Here, we found significant increase in component 3 (C3) expression in the prefrontal cortex (PFC) of depressed suicide subjects. We tested the role of altered C3 expression in mouse model of depression and found that increased C3 expression in PFC as a result of chronic stress causes depressive-like behavior. Conversely, mice lacking C3 were resilient to stress-induced depressive-like behavior. Moreover, selective overexpression of C3 in PFC was sufficient to cause depressive-like behavior in mice. We found that C3a (activated product of C3) receptor, C3aR+ monocytes were infiltrated into PFC following chronic stress. However, C3aR knockout mice displayed significantly reduced monocyte recruitment into PFC and reduced levels of the proinflammatory cytokine IL-1β in PFC after chronic stress. In addition, C3aR knockout mice did not exhibit chronic stress-induced behavior despair. Similarly, chronic stress-induced increases in C3aR+ monocytes and IL-1β in PFC, and depressive-like behavior were attenuated by myeloid cell depletion. These postmortem and preclinical studies identify C3aR signaling as a key factor in MDD pathophysiology.

Schizophrenia heterogeneity revisited: Clinical, cognitive, and psychosocial correlates of statistically-derived negative symptoms subgroups

Traditional efforts to delineate the clinical heterogeneity of schizophrenia have been unsuccessful because of the absence of a valid, stable, and meaningful subtyping scheme. A clinically-informed nosology supported by multivariate statistical classification methods may provide a better approach for classifying schizophrenia. The goals of the current study were to 1) use multivariate classification methods to validate a clinical subtyping scheme based on the profile of negative symptoms; and 2) following validation to contrast the statistically-derived subgroups to ascertain distinguishing demographic, clinical, cognitive, and functional characteristics. In the current study, 706 people with schizophrenia completed measures of positive and negative symptoms, premorbid adjustment, cognition, and psychosocial functioning. Latent class analysis served to identify the number of negative symptom subgroups in schizophrenia. Next, statistical classification methods-Bayes Theorem and the Base Rate Classification Technique-were used to assign participants into the identified subgroups. Subgroups were compared on external validation variables not used in the classification process via logistic regression and discriminant function analysis. Latent class analysis supported a three-class model of schizophrenia that included deficit, persistent, and transient negative symptom subgroups. Posthoc comparisons showed that demographic characteristics, positive symptoms, premorbid adjustment, and cognitive profiles can distinguish the schizophrenia subgroups with moderate accuracy. The deficit subgroup had the greatest impairments in psychosocial functioning and quality of life variables. Findings suggest that schizophrenia encapsulates qualitatively distinct negative symptom subgroups that differ in their demographic, symptomatic, neuropsychological, and functional profiles. Schizophrenia heterogeneity reflects a combination of non-arbitrary subgroups and severity-based differences in negative symptoms.

International efforts at implementing and advancing the recovery model

For almost a century the medical model has been the overarching framework for mental healthcare but since the 1980s it has been challenged by a consumer/survivor movement. Central to this revolution is the recovery model, which suggests that mental illness is only one of many facets of the life of an individual with mental illness, and that a full, meaningful life is possible despite illness (Anthony, 1993). The medical model emphasises the role of symptomatic improvements and functional status, and considers recovery as an ‘outcome’ or ‘end state’, at which point symptoms are remitted and community functioning is restored. In contrast, the recovery model underscores hope, empowerment, the self-management of illness and some aspects of community functioning, such as social support and role functioning, which operate in a non-linear fashion throughout the recovery journey.

Altered Expression of Endoplasmic Reticulum Stress-Related Genes in the Middle Frontal Cortex of Subjects with Autism Spectrum Disorder

The endoplasmic reticulum (ER) is an important organelle responsible for the folding and sorting of proteins. Disturbances in ER homeostasis can trigger a cellular response known as the unfolded protein response, leading to accumulation of unfolded or misfolded proteins in the ER lumen called ER stress. A number of recent studies suggest that mutations in autism spectrum disorder (ASD)-susceptible synaptic genes induce ER stress. However, it is not known whether ER stress-related genes are altered in the brain of ASD subjects. In the present study, we investigated the mRNA expression of ER stress-related genes (ATF4, ATF6, PERK, XBP1, sXBP1, CHOP, and IRE1) in the postmortem middle frontal gyrus of ASD and control subjects. RT-PCR analysis showed significant increases in the mRNA levels of ATF4, ATF6, PERK, XBP1, CHOP, and IRE1 in the middle frontal gyrus of ASD subjects. In addition, we found a significant positive association of mRNA levels of ER stress genes with the diagnostic score for stereotyped behavior in ASD subjects. These results, for the first time, provide the evidence of the dysregulation of ER stress genes in the brain of subjects with ASD.

Complement C3 Expression Is Decreased in Autism Spectrum Disorder Subjects and Contributes to Behavioral Deficits in Rodents

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with hallmark symptoms including social deficits, communication deficits and repetitive behaviors. Accumulating evidence suggests a potential role of the immune system in the pathophysiology of ASD. The complement system represents one of the major effector mechanisms of the innate immune system, and regulates inflammation, and orchestrates defense against pathogens. However, the role of CNS complement system in ASD is not well understood. In the present study, we found a significant increase in C2, C5, and MASP1, but a decrease in C1q, C3, and C4 mRNA levels in the middle frontal gyrus of ASD subjects compared to controls. Significant decreases in the mRNA levels of 2 key proinflammatory cytokines, IL-17 and IL-23 were observed in ASD subjects. Our study further demonstrated a strong association of complement genes with IL-17 and IL-23, suggesting a possible role of the complement system in immune dysregulation in ASD. We observed significant associations between complement components and abnormality of development scores in subjects with ASD. In rodents, C3 knockdown in the prefrontal cortex induced social interaction deficits and repetitive behavior in mice. Together, these studies suggest a potential role of C3 in the pathophysiology of ASD.

Transglutaminase 2 overexpression induces depressive-like behavior and impaired TrkB signaling in mice

Serotonin (5-hydroxytryptamine, 5-HT) and brain-derived neurotrophic factor (BDNF) are two signaling molecules that have important regulatory roles in the development and plasticity of neural circuits that are known to be altered in depression. However, the mechanism by which 5-HT regulates BDNF signaling is unknown. In the present study, we found that 5-HT treatment increases BDNF receptor, TrkB (tropomyosin related kinase B), levels in mouse primary cortical neurons via a Rac1 (RAS-related C3 botulinum toxin substrate 1)-dependent mechanism. Significant increases in the levels of type-2 transglutaminase (TG2, which is implicated in transamidation of 5-HT to Rac1) are observed in the mouse prefrontal cortex (PFC) following chronic exposure to stress. We also found that TG2 levels are increased in the post-mortem PFC of depressed suicide subjects relative to matched controls. Moreover, in mice, neuronal overexpression of TG2 resulted in the atrophy of neurons and reduced levels of TrkB in the PFC as well as a depressive-like phenotype. Overexpression of TG2 in mouse cortical neurons reduced TrkB levels as a result of impaired endocytosis of TrkB. TG2 inhibition by either a viral particle or pharmacological approach attenuated behavioral deficits caused by chronic unpredictable stress. Moreover, the overexpression of TrkB in the mouse PFC ameliorated the depressive-like phenotype of TG2-overexpressed mice. Taken together, these post-mortem and preclinical findings identify TG2 as a critical mediator of the altered TrkB expression and depressive-like behaviors associated with chronic exposure to stress and suggest that TG2 may represent a novel therapeutic target in depression.

An examination of neurocognition and symptoms as predictors of post-hospital community tenure in treatment resistant schizophrenia

Neurocognition and psychopathology are robust predictors of community functioning and relapse/rehospitalization in schizophrenia. Existing studies are however limited because they have ignored the most chronic, treatment-resistant patients. Moreover, the prediction of functional outcomes has yet to be extended to the duration of community tenure, an indicator of the capacity of chronically-hospitalized patients to gain traction in the community. The current study examined neurocognition and symptom severity at discharge as potential predictors of community tenure in chronically-hospitalized treatment-resistant patients. The study recruited 90 people with treatment-resistant schizophrenia who received services on an inpatient unit. Participants completed measures of psychopathology and neurocognition prior to discharge. Following discharge, participants were tracked at current residences six months and one year post-discharge to assess community tenure. The percentage of individuals who continued to live in the community at 12-month follow-up was 51%. Severe negative symptoms but not neurocognitive impairment or positive symptoms was a significant predictor of shorter post-hospital community tenure. Of the negative symptoms domain, anhedonia-asociality proved to be the most relevant predictor of community tenure in the sample. The capacity to elicit goal-directed behaviors in response to anticipated physical and social rewards may be an important treatment target for sustaining community tenure.

Latent variable mixture modeling in psychiatric research--a review and application

Latent variable mixture modeling represents a flexible approach to investigating population heterogeneity by sorting cases into latent but non-arbitrary subgroups that are more homogeneous. The purpose of this selective review is to provide a non-technical introduction to mixture modeling in a cross-sectional context. Latent class analysis is used to classify individuals into homogeneous subgroups (latent classes). Factor mixture modeling represents a newer approach that represents a fusion of latent class analysis and factor analysis. Factor mixture models are adaptable to representing categorical and dimensional states of affairs. This article provides an overview of latent variable mixture models and illustrates the application of these methods by applying them to the study of the latent structure of psychotic experiences. The flexibility of latent variable mixture models makes them adaptable to the study of heterogeneity in complex psychiatric and psychological phenomena. They also allow researchers to address research questions that directly compare the viability of dimensional, categorical and hybrid conceptions of constructs.

Predictors of Long-Term Change in Adult Cognitive Performance: Systematic Review and Data from the Northern Finland Birth Cohort 1966

OBJECTIVE

Several social life events and challenges have an impact on cognitive development. Our goal was to analyze the predictors of change in cognitive performance in early midlife in a general population sample. Additionally, systematic literature review was performed.

METHOD

The study sample was drawn from the Northern Finland Birth Cohort 1966 at the ages of 34 and 43 years. Primary school performance, sociodemographic factors and body mass index (BMI) were used to predict change in cognitive performance measured by the California Verbal Learning Test, Visual Object Learning Test, and Abstraction Inhibition and Working Memory task. Analyses were weighted by gender and education, and p-values were corrected for multiple comparisons using Benjamini-Hochberg procedure (B-H).

RESULTS

Male gender predicted decrease in episodic memory. Poor school marks of practical subjects, having no children, and increase in BMI were associated with decrease in episodic memory, though non-significantly after B-H. Better school marks, and higher occupational class were associated with preserved performance in visual object learning. Higher vocational education predicted preserved performance in visual object learning test, though non-significantly after B-H. Likewise, having children predicted decreased performance in executive functioning but non-significantly after B-H.

CONCLUSIONS

Adolescent cognitive ability, change in BMI and several sociodemographic factors appear to predict cognitive changes in early midlife. The key advantage of present study is the exploration of possible predictors of change in cognitive performance among general population in the early midlife, a developmental period that has been earlier overlooked.

Neurocognition as a predictor of outcome in schizophrenia in the Northern Finland Birth Cohort 1966

The purpose of this study was to study neurocognitive performance as a predictor of outcomes in midlife schizophrenia. There is a lack of studies with unselected samples and a long follow-up. The study is based on the prospective, unselected population-based Northern Finland Birth Cohort 1966. The study includes 43 individuals with schizophrenia and 73 controls, whose neurocognitive performance was assessed twice, at 34 and 43 years. At both time points we used identical neurocognitive tests to assess verbal and visual memory and executive functions. Our main aim was to analyse neurocognitive performance at 34 years as a predictor of clinical, vocational and global outcomes at 43 years. Additionally, the analysis addressed cross-sectional associations between cognitive performance and clinical, vocational and global measures at 43 years. The assessment of outcomes was performed in the schizophrenia group only. In the longitudinal analysis poorer visual memory predicted poorer vocational outcome and poorer long-term verbal memory predicted poorer global outcome. In the cross-sectional analysis poorer visual memory and lower composite score of neurocognition were associated with poorer global outcome. No individual neurocognitive test or the composite score of these predicted remission. These data indicate that neurocognition, especially memory function, is an important determinant of long-term functional outcome in midlife schizophrenia.

A randomized study of cognitive remediation for forensic and mental health patients with schizophrenia

Cognitive remediation has proven efficacy for improving neurocognition in people with schizophrenia. The current study evaluated the benefits of cognitive remediation on neurocognition, functioning, psychotic symptoms, and aggression in a sample of forensic and mental health patients. Care recipients with schizophrenia or schizoaffective disorder (N = 78) receiving services in the forensic and mental health units of a state hospital were randomized to participate in cognitive remediation versus computer games control activities. Participants' neurocognition, functional capacity, experiential recovery, psychotic symptoms, and aggression incidents were assessed at baseline and posttreatment. Cognitive remediation was associated with improvements in several neurocognitive domains and circumscribed domains of functional capacity. People assigned to cognitive remediation experiences greater reductions in negative symptoms, agitation/excitement, and verbal and physical aggression. In addition to improving neurocognition in long-term hospitalized forensic and mental health patients, cognitive remediation may enhance efforts at reducing negative symptoms, emotion dysregulation, and aggression incidents. Forensic settings may represent a new frontier for the clinical dissemination of cognitive remediation.

Are Negative Symptoms Dimensional or Categorical? Detection and Validation of Deficit Schizophrenia With Taxometric and Latent Variable Mixture Models

Studies have supported the validity of the deficit form of schizophrenia (ie, people with primary and enduring negative symptoms). A test of whether that group is a true taxon-that is, a distinct, discontinuous group-has yet to be conducted and the underlying structure of negative symptoms as categorical or dimensional remains undetermined. The present study examined the latent structure of negative and deficit symptoms to determine if a nonarbitrary boundary distinguishes deficit from nondeficit forms of schizophrenia (ie, whether these symptoms reflect a continuous or categorical variable). Schedule for the Deficit Syndrome ratings of 789 individuals with a psychotic disorder were submitted to taxometric and latent variable mixture analyses to test categorical vs dimensional hypotheses of negative symptoms and deficit schizophrenia. Analytic models favored a taxonic structure of negative symptoms and the validity of the deficit/nondeficit classification scheme. Taxometric classification outperformed clinician-based deficit/nondeficit classification in its association with summer birth, male sex, premorbid adjustment, neurocognition, and psychosocial functioning. Within taxon and complement classes, severity scores remained significant predictors of premorbid adjustment, neurocognition, and psychosocial functioning. Thus, although a categorical approach is validated, a hybrid categorical-dimensional conceptualization of negative symptoms also has validity for the prediction of external variables.

The professional experiences of peer specialists in the Georgia Mental Health Consumer Network

There has been an increase in the number of peer-led services within the mental health care system. There however remains little information about the experiences of peers serving in such helping roles. This study explored the professional experiences of peer specialists including the basic roles, benefits, and potential challenges of the peer specialist role. Peer specialists (N = 84) completed a battery of surveys and questionnaires. Qualitative analysis of participants' responses indicated that peer specialists face difficulties such as poor compensation, limited employment opportunities, work stress, emotional stress in helping others, and maintaining personal wellness. Quantitative analyses revealed that recovery attitudes may confer clinical and psychosocial benefits for peer specialists and employment may contribute to hope, empowerment, social engagement, and competence. Peer specialists would benefit from resources and supports aimed at their continued training and supervision. Fostering the vocational advancement of peer specialists could potentially enhance their experiential recovery and community functioning.

Brain-derived neurotrophic factor (BDNF) and neurocognitive deficits in people with schizophrenia: a meta-analysis

Studies suggest that the BDNF Val66Met (rs6265) polymorphism is associated with the incidence of schizophrenia and neurocognitive functioning. These associations appear to be however somewhat mixed. We conducted two separate meta-analyses to investigate (1) the association between the Val66Met polymorphism and neurocognition in people with schizophrenia and (2) the association between peripheral expression of BDNF and neurocognitive phenotypes. For the first aim, we identified 12 studies and 67 comparisons of Met allele carriers and Val homozygotes. These comparisons included 1890 people with schizophrenia (men=1465, women=553), of whom 972 were Met allele carriers and 918 were Val homozygotes. For the second aim, we identified five studies and 25 correlations of peripheral BDNF and neurocognitive scores. The meta-analysis for the second aim included 414 people with schizophrenia (men=292, women=170). First, we found non-significant difference between the genotype groups on most neurocognitive domains. Second, correlations between peripheral BDNF and neurocognitive phenotypes were minimal but we obtained significant effects for the reasoning and problem-solving domains; thus, higher levels of BDNF expression corresponded to better performance on reasoning/problem-solving tasks. The meta-analyses did not robustly establish an association between BDNF Val66Met polymorphism and neurocognition in schizophrenia.

Dysregulation of estrogen receptor beta (ERβ), aromatase (CYP19A1), and ER co-activators in the middle frontal gyrus of autism spectrum disorder subjects

BACKGROUND

Autism spectrum disorders (ASD) are much more common in males than in females. Molecular alterations within the estrogen receptor (ER) signaling pathway may contribute to the sex difference in ASD, but the extent of such abnormalities in the brain is not known.

METHODS

Postmortem middle frontal gyrus tissues (13 ASD and 13 control subjects) were used. The protein levels were examined by western blotting. The gene expression was determined by qRT-PCR.

RESULTS

Gene expression analysis identified a 35% decrease in ERβ mRNA expression in the middle frontal gyrus of ASD subjects. In addition, a 38% reduction in aromatase (CYP19A1) mRNA expression was observed in ASD subjects. We also found significant decreases in ER co-activators that included a 34% decrease in SRC-1, a 77% decrease in CBP, and a 52% decrease in P/CAF mRNA levels in ASD subjects relative to controls. There were no differences in the mRNA levels of TIF-2, AIB-1 (ER co-activators), ER co-repressors (SMRT and nCoR) and ERα in the middle frontal gyrus of ASD subjects as compared to controls. We observed significant correlations between ERβ, CYP19A1, and co-activators in the study subjects. Immunoblot analysis further confirmed the changes in ERβ and aromatase at the protein level in the control and ASD subjects.

CONCLUSIONS

These results, for the first time, provide the evidence of the dysregulation of ERβ and co-factors in the brain of subjects with ASD.

Ubiquitin-proteasome dependent degradation of GABAAα1 in autism spectrum disorder

BACKGROUND

Although the neurobiological basis of autism spectrum disorder (ASD) is not fully understood, recent studies have indicated the potential role of GABAA receptors in the pathophysiology of ASD. GABAA receptors play a crucial role in various neurodevelopmental processes and adult neuroplasticity. However, the mechanism(s) of regulation of GABAA receptors in ASD remains poorly understood.

METHODS

Postmortem middle frontal gyrus tissues (13 ASD and 13 control subjects) were used. In vitro studies were performed in primary cortical neurons at days in vitro (DIV) 14. The protein levels were examined by western blotting. Immunofluorescence studies were employed for cellular localization. The gene expression was determined by RT-PCR array and qRT-PCR.

RESULTS

A significant decrease in GABAAα1 protein, but not mRNA levels was found in the middle frontal gyrus of ASD subjects indicating a post-translational regulation of GABAA receptors in ASD. At the cellular level, treatment with proteasomal inhibitor, MG132, or lactacystin significantly increased GABAAα1 protein levels and Lys48-linked polyubiquitination of GABAAα1, but reduced proteasome activity in mouse primary cortical neurons (DIV 14 from E16 embryos). Moreover, treatment with betulinic acid, a proteasome activator significantly decreased GABAAα1 protein levels in cortical neurons indicating the role of polyubiquitination of GABAAα1 proteins with their subsequent proteasomal degradation in cortical neurons. Ubiquitination specific RT-PCR array followed by western blot analysis revealed a significant increase in SYVN1, an endoplasmic reticulum (ER)-associated degradation (ERAD) E3 ubiquitin ligase in the middle frontal gyrus of ASD subjects. In addition, the inhibition of proteasomal activity by MG132 increased the expression of GABAAα1 in the ER. The siRNA knockdown of SYVN1 significantly increased GABAAα1 protein levels in cortical neurons. Moreover, reduced association between SYVN1 and GABAAα1 was found in the middle frontal gyrus of ASD subjects.

CONCLUSIONS

SYVN1 plays a critical role as an E3 ligase in the ubiquitin proteasome system (UPS)-mediated GABAAα1 degradation. Thus, inhibition of the ubiquitin-proteasome-mediated GABAAα1 degradation may be an important mechanism for preventing GABAAα1 turnover to maintain GABAAα1 levels and GABA signaling in ASD.

Psychopharmacological treatment of neurocognitive deficits in people with schizophrenia: a review of old and new targets

Neurocognitive impairments significantly contribute to disability and the overall clinical picture in schizophrenia spectrum disorders. There has therefore been a concerted effort, guided by the discovery of neurotransmitter and synaptic systems in the central nervous system, to develop and test compounds that may ameliorate neurocognitive deficits. The current article summarizes the results of efforts to test neurocognitive-enhancing agents in schizophrenia. Overall, existing clinical trials provide little reason to be enthusiastic about the benefits of psychopharmacological agents at enhancing neurocognition in schizophrenia-a state of affairs that may reflect the inadequacy of single neurotransmitter or receptor models. The etiologic and phenomenological complexity of neurocognitive deficits in schizophrenia may be better served by psychopharmacological agents that (i) target neurotransmitter systems proximal in the causal chain to neurocognitive deficits; (ii) enhance distal survival processes in the central nervous system-neurogenesis, neuronal growth, synaptogenesis, and connectivity; and (iii) counteract the negative effects of aberrant neurodevelopment in schizophrenia, such as neuroinflammation and oxidative stress. Future efforts to develop psychopharmacological agents for neurocognitive impairment in schizophrenia should reflect the knowledge of its complex etiology by addressing aberrations along its causal chain. Clinical trials may benefit methodologically from (i) an appreciation of the phenomenological heterogeneity of neurocognitive deficits in schizophrenia; (ii) a characterization of the predictors of treatment response; and (iii) a recognition of issues of sample size, statistical power, treatment duration, and dosing.