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1.
Vision Res ; 219: 108394, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38579407

RESUMO

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.


Assuntos
Percepção de Forma , Esquizofrenia , Humanos , Percepção de Forma/fisiologia , Esquizofrenia/fisiopatologia , Adulto , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Limiar Sensorial/fisiologia , Estimulação Luminosa/métodos , Estudos de Casos e Controles , Reconhecimento Visual de Modelos/fisiologia , Adulto Jovem
2.
Schizophr Res Cogn ; 37: 100309, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38550527

RESUMO

Schizophrenia and bipolar disorder are associated with cognitive deficits that contribute significantly to disability. However, traditional in-lab cognitive assessments are time-consuming and not optimized for remote administration. Recent advancements in smartphone technology enable momentary cognitive assessments in a real-world context. This brief report reviews recent research in momentary cognitive assessments in individuals with schizophrenia and bipolar disorder through reviewing mobile platforms and cognitive assessments studied. A total of 14 experimental articles were reviewed, focusing on cognitive domains including visual working memory, processing speed, executive function, verbal fluency, verbal memory, social cognition, and typing patterns. The review highlights the feasibility of remote cognitive assessment with smartphones, and provides a layout of domains studied in this context, but illustrates a low volume of current research, the need for additional studies, and the potential for innovations like digital phenotyping.

3.
Psychiatry Res ; 329: 115488, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37769371

RESUMO

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.


Assuntos
Experiências Adversas da Infância , Esquizofrenia , Adulto , Humanos , Ideação Suicida , Tentativa de Suicídio , Probabilidade
4.
Psychiatry Res Neuroimaging ; 329: 111597, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36680843

RESUMO

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.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Anedonia , Encéfalo/diagnóstico por imagem , Transtornos do Humor , Motivação
6.
Schizophr Res ; 256: 117-125, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36424289

RESUMO

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.


Assuntos
Remediação Cognitiva , Transtornos Psicóticos , Esquizofrenia , Humanos , Masculino , Adulto , Feminino , Esquizofrenia/complicações , Esquizofrenia/terapia , Cognição Social , Transtornos Psicóticos/complicações , Transtornos Psicóticos/terapia , Transtornos Psicóticos/psicologia , Agressão , Resultado do Tratamento , Cognição
7.
Schizophr Res ; 250: 127-133, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36403294

RESUMO

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.


Assuntos
Esquizofrenia , Masculino , Feminino , Humanos , Testes Neuropsicológicos , Análise Fatorial , Cognição , Memória
10.
Schizophr Bull ; 48(3): 620-630, 2022 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-35020936

RESUMO

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.


Assuntos
Apatia , Esquizofrenia , Anedonia , Humanos , Transtornos do Humor , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico
11.
Neuroinformatics ; 20(1): 261-275, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34846691

RESUMO

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.


Assuntos
Neuroimagem , Feminino , Humanos , Masculino , Neuroimagem/métodos
12.
Psychol Assess ; 33(8): 746-755, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33983785

RESUMO

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).


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Testes Neuropsicológicos , Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Análise Fatorial , Humanos , Reprodutibilidade dos Testes , Instituições Acadêmicas
13.
Mol Psychiatry ; 26(7): 3043-3059, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33833372

RESUMO

Chronic stress is a major risk factor in the pathophysiology of many neuropsychiatric disorders. Further, chronic stress conditions can promote neuroinflammation and inflammatory responses in both humans and animal models. Type I interferons (IFN-I) are critical mediators of the inflammatory response in the periphery and responsible for the altered mood and behavior. However, the underlying mechanisms are not well understood. In the present study, we investigated the role of IFN-I signaling in chronic stress-induced changes in neuroinflammation and behavior. Using the chronic restraint stress model, we found that chronic stress induces a significant increase in serum IFNß levels in mice, and systemic blockade of IFN-I signaling attenuated chronic stress-induced infiltration of macrophages into prefrontal cortex and behavioral abnormalities. Furthermore, complement component 3 (C3) mediates systemic IFNß-induced changes in neuroinflammation and behavior. Also, we found significant increases in the mRNA expression levels of IFN-I stimulated genes in the prefrontal cortex of depressed suicide subjects and significant correlation with C3 and inflammatory markers. Together, these findings from animal and human postmortem brain studies identify a crucial role of C3 in IFN-I-mediated changes in neuroinflammation and behavior under chronic stress conditions.


Assuntos
Complemento C3 , Interferon Tipo I , Doenças Neuroinflamatórias , Estresse Psicológico , Animais , Camundongos , Camundongos Endogâmicos C57BL , Doenças Neuroinflamatórias/imunologia
14.
Neuropsychobiology ; 80(5): 411-424, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33706323

RESUMO

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.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Esquizofrenia , Encéfalo/diagnóstico por imagem , Fator Neurotrófico Derivado do Encéfalo/genética , Genótipo , Hipocampo , Humanos , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética
15.
J Psychiatr Res ; 136: 132-139, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33588227

RESUMO

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.


Assuntos
Transtornos Cognitivos , Esquizofrenia , Cognição , Transtornos Cognitivos/etiologia , Análise Fatorial , Humanos , Esquizofrenia/complicações , Esquizofrenia/tratamento farmacológico , Resultado do Tratamento
16.
Brain Sci ; 12(1)2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35053815

RESUMO

Over the past century, advancements in psychiatric treatments have freed countless individuals from the burden of life-long, incapacitating mental illness. These treatments have largely been discovered by chance. Theory has driven advancement in the natural sciences and other branches of medicine, but psychiatry remains a field in its "infancy". The targets for healing in psychiatry lie within the realm of the mind's subjective experience and thought, which we cannot yet describe in terms of their biological underpinnings in the brain. Our technology is sufficiently advanced to study brain neurons and their interactions on an electrophysiological and molecular level, but we cannot say how these form a single feeling or thought. While psychiatry waits for its "Copernican Revolution", we continue the work in developing theories and associated experiments based on our existing diagnostic systems, for example, the Diagnostic and Statistical Manual of Mental Disorders (DSM), International Classification of Diseases (ICD), or the more newly introduced Research Domain Criteria (RDoC) framework. Understanding the subjective reality of the mind in biological terms would doubtless lead to huge advances in psychiatry, as well as to ethical dilemmas, from which we are spared for the time being.

17.
Asian J Psychiatr ; 55: 102522, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33360707

RESUMO

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.


Assuntos
Reprodutibilidade dos Testes , China , Hong Kong , Humanos , Itália , Escalas de Graduação Psiquiátrica , Psicometria
18.
Schizophr Bull ; 47(2): 386-394, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32909606

RESUMO

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.


Assuntos
Sintomas Afetivos/fisiopatologia , Anedonia/fisiologia , Afasia/fisiopatologia , Motivação/fisiologia , Psicometria/estatística & dados numéricos , Transtornos Psicóticos/fisiopatologia , Comportamento Social , Adolescente , Adulto , Sintomas Afetivos/etiologia , Afasia/etiologia , Consenso , Análise Fatorial , Feminino , Humanos , Masculino , Modelos Estatísticos , Testes Neuropsicológicos , Transtornos Psicóticos/complicações , Síndrome , Adulto Jovem
20.
Focus (Am Psychiatr Publ) ; 18(4): 436-439, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33343256
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