Component mechanisms of executive function in schizophrenia and their contribution to functional outcomes.

OBJECTIVE: In schizophrenia, scores reflecting deficits in different cognitive processes are strongly correlated, making it difficult to establish a solid relationship between different cognitive mechanisms and other features of this disorder. The objective of this study was to explore whether three frequently postulated executive functions (updating, shifting, and inhibition) could be compared between groups and considered independently in terms of their respective roles in functional outcome. METHODS: This study relied on confirmatory factor analysis of schizophrenia patients (n=141) and healthy controls (n=119). The main analyses examined the degree to which three executive functions (updating, set-shifting, and inhibition) could be separated in schizophrenia and compared this model among groups. Structural equation modeling analysis was also performed to examine the extent to which executive function components contribute to functional outcome in schizophrenia. RESULTS: Multiple-group confirmatory factor analysis with unconstrained model parameters indicated that the full three-factor model may fit the data in both groups (χ2 = 61.48, degrees of freedom = 34, p < 0.001, comparative fit index = 0.95; standardized root mean square residual = 0.037; root mean square error of approximation = 0.04; Akaike's information criteria = 169.49; normed fit index = 0.90), although there was also a good data fit for the patient group with a two-factor model. In the patient group, structural equation modeling suggested that shifting and (principally) updating were associated with the general measure of functional outcome (regression path coefficients: 0.34, p < 0.005; 0.39, p < 0.005, respectively), although when combined the mechanisms fail to contribute. CONCLUSION: This data suggests that the factor structure may be similar but not identical between groups, and both updating and shifting may play an important role in functional outcome in schizophrenia.

Eye Movements and Cognitive Strategy in a Fluid Intelligence Test: Item Type Analysis.

Eye movements help to infer the cognitive strategy that a person uses in fluid intelligence tests. However, intelligence tests demand different relations/rules tokens to be solved, such as rule direction, which is the continuation, variation or overlay of geometric figures in the matrix of the intelligence test. The aim of this study was to understand whether eye movements could predict the outcome of an intelligence test and in the rule item groups. Furthermore, we sought to identify which measure is best for predicting intelligence test scores and to understand if the rule item groups use the same strategy. Accordingly, 34 adults completed a computerized intelligence test with an eye-tracking device. The toggling rate, that is, the number of toggles on each test item equalized by the item latency explained 45% of the variance of the test scores and a significant amount of the rule tokens item groups. The regression analyses also indicated toggling rate as the best measure for predicting the score and that all the rule tokens seem to respect the same strategy. No correlation or difference were found between baseline pupil size and fluid intelligence. Wiener Matrizen-Test 2 was demonstrated to be a good instrument for the purpose of this study. Finally, the implications of these findings for an understanding of cognition are discussed.

Theory of mind complex task: validity based on relationships with external variables / Tarefa complexa de teoria da mente: validade baseada nas relações com variáveis externas / Tarea compleja de la teoría de la mente: validez basada en relaciones con variables externas

Most research on Theory of Mind (ToM) focuses on preschool years, with few studies targeting later years, especially in the national context. This study aimed to investigate evidence of the validity of a Theory of Mind Complex Task from the relationship with the external variables: age, type of school, and vocabulary. Ninety-eight children, aged between 6 and 9, from private and public schools participated. Results showed age and school effect, with better performance of children from private schools. There was a positive, significant, and moderate magnitude correlation with vocabulary. This study provides the first sources of evidence of task validity, indicating that age and type of school were relevant variables for ToM performance, and therefore should be considered in the elaboration of future norms.

A maior parte das pesquisas sobre a teoria da mente (ToM) concentra-se nos anos pré-escolares, sendo poucos os estudos direcionados aos anos posteriores, principalmente em contexto nacional. O objetivo deste estudo foi investigar evidências de validade de uma tarefa complexa de ToM a partir da relação com variáveis externas: idade, tipo de escola e vocabulário. Participaram 98 crianças, entre 6 e 9 anos de idade, de escolas privadas e públicas. Os resultados obtidos mostraram efeito de idade e de escola, com melhor desempenho das crianças de escolas privadas. Houve correlação positiva, significativa e de magnitude moderada com vocabulário. Este estudo disponibiliza as primeiras fontes de evidências de validade da tarefa, indicando que idade e tipo de escola se mostraram variáveis relevantes para o desempenho em ToM, as quais, por isso, devem ser consideradas na elaboração de normas futuras.

Las investigaciones sobre la teoría de la mente (ToM) se centra en los años preescolares, especialmente en el contexto nacional. El objetivo de este estudio fue investigar la evidencia de la validez de una tarea compleja de la ToM a partir de la relación con variables externas: edad, tipo de escuela y vocabulario. Participaron 98 niños, de edades comprendidas entre 6 y 9 años, de escuelas privadas y públicas. Los resultados mostraron efecto de la edad y escolar, con un mejor desempeño de los niños de escuelas privadas. Hubo una correlación de magnitud moderada, positiva y significativa con el vocabulario. Este estudio proporciona las primeras fuentes de evidencia de la validez de la tarea, indicando que la edad y el tipo de escuela son variables relevantes para el desempeño de la ToM y, por lo tanto, deberían considerarse en la elaboración de normas futuras.

Word loss trajectory in autism spectrum disorder: analysis of home videos / Perda de palavras no transtorno do espectro autista: análise de vídeos caseiros / Pérdida del vocabulario en el trastorno del espectro autista: análisis de videos caseros

The regression of previously acquired skills has been highlighted as a potential early indicator of Autism Spectrum Disorder (ASD). The aims of the study were to validate parental reports regarding the occurrence of word loss and to investigate the characteristics of the words and other skills in a child aged 42 months with ASD over a 10-month period. It is a longitudinal and exploratory case study using systematic observation. Ten home videos showing the child's behavior between 13 and 23 months of age were analyzed according to the home video observation protocol and PROTEA-R. A total of 171 episodes involving the investigated behaviors were identified, which included the use of 51 words (the majority being nouns). Word loss and loss of other skills (play and social abilities) were observed. Word loss was the first or primary motive for parental concern, reinforcing that this phenomenon constitutes a potential early indicator of ASD.

A regressão de habilidades previamente adquiridas tem sido destacada como um potencial indicador precoce do Transtorno do Espectro Autista (TEA). Os objetivos do estudo de caso longitudinal e exploratório, utilizando observação sistemática foram validar os relatos dos pais sobre a perda de palavras, investigar suas características e outras habilidades em uma criança de 42 meses com TEA ao longo de um período de 10 meses. Foram analisados dez vídeos mostrando o comportamento da criança entre 13 e 23 meses de idade de acordo com um protocolo de observação de vídeos caseiros e do PROTEA-R. Analisamos 171 episódios envolvendo os comportamentos investigados, incluindo o uso de 51 palavras (a maioria substantivos). Observamos perda de palavras e perda de outras habilidades (de brincar e habilidades sociais). A perda de palavras foi o primeiro ou principal motivo de preocupação dos pais, reforçando que esse fenômeno constitui um indicador precoce potencial de TEA.

La regresión de habilidades previamente adquiridas es destacada como un potencial indicador precoz del Trastorno del Espectro del Autismo (TEA). Los objetivos del estudio de caso longitudinal y exploratorio, utilizando observación sistemática, fueron validar relatos de los padres sobre pérdida de vocabulario, investigar sus características y otras habilidades en un niño de 42 meses con TEA en un período de 10 meses. Se analizaron diez vídeos mostrando la conducta del niño entre 13 y 23 meses de edad de acuerdo con un protocolo de observación de vídeos caseros y el PROTEA-R. Analizamos 171 episodios que involucra los comportamientos investigados, incluyendo el uso de 51 palabras (la mayoría de ellos sustantivos). Observamos pérdida de vocabulario y pérdida de otras habilidades (jugar y habilidades sociales). La pérdida de vocabulario fue el primer o principal motivo de preocupación de los padres, reforzando que ese fenómeno constituye un indicador precoz potencial de TEA.

Component mechanisms of executive function in schizophrenia and their contribution to functional outcomes

Objective: In schizophrenia, scores reflecting deficits in different cognitive processes are strongly correlated, making it difficult to establish a solid relationship between different cognitive mechanisms and other features of this disorder. The objective of this study was to explore whether three frequently postulated executive functions (updating, shifting, and inhibition) could be compared between groups and considered independently in terms of their respective roles in functional outcome. Methods: This study relied on confirmatory factor analysis of schizophrenia patients (n=141) and healthy controls (n=119). The main analyses examined the degree to which three executive functions (updating, set-shifting, and inhibition) could be separated in schizophrenia and compared this model among groups. Structural equation modeling analysis was also performed to examine the extent to which executive function components contribute to functional outcome in schizophrenia. Results: Multiple-group confirmatory factor analysis with unconstrained model parameters indicated that the full three-factor model may fit the data in both groups (χ2 = 61.48, degrees of freedom = 34, p < 0.001, comparative fit index = 0.95; standardized root mean square residual = 0.037; root mean square error of approximation = 0.04; Akaike's information criteria = 169.49; normed fit index = 0.90), although there was also a good data fit for the patient group with a two-factor model. In the patient group, structural equation modeling suggested that shifting and (principally) updating were associated with the general measure of functional outcome (regression path coefficients: 0.34, p < 0.005; 0.39, p < 0.005, respectively), although when combined the mechanisms fail to contribute. Conclusion: This data suggests that the factor structure may be similar but not identical between groups, and both updating and shifting may play an important role in functional outcome in schizophrenia.

Investigation of cognition in schizophrenia: psychometric properties of instruments for assessing working memory updating / Investigação da cognição na esquizofrenia: propriedades psicométricas de instrumentos para avaliação de atualização da memória de trabalho

Objective This study describes the development of two updating measures of working memory (WM): Letter Updating Test (LUT) and Word Updating Test (WUT). Methods In stage 1, items were created and the instruments were assessed by experts and laymen. In stage 2, tests were given to 15 patients with schizophrenia and 15 paired controls. All were able to understand and respond to the instruments. In stage 3, 141 patients with schizophrenia and 119 healthy controls aged 18 to 60 took part; they were assessed on WM, processing speed (PS) and functional outcome. Results The results showed adequate rates of internal consistency for both measures developed, for both the total sample and each group separately, as well as evidence of convergent validity, discriminant validity and sensitivity to differentiate performance among the groups. Principal component analysis yielded two components, one for updating tests and other for PS measures, indicating factorial validity. Positive and significant, yet low, correlations were found with functionality measures. Conclusion These results provide adequate psychometric parameters for the measures developed, applicable to cognitive research settings in schizophrenia.

Objetivo O estudo descreve o desenvolvimento de duas medidas de atualização da memória de trabalho (MT): Teste de Atualização de Letras (TAL) e Teste de Atualização de Palavras (TAP). Métodos Na etapa 1 foram criados itens e os instrumentos foram analisados por experts e leigos. Na etapa 2, os testes foram aplicados em 15 pacientes com esquizofrenia e 15 controles pareados. Todos foram capazes de compreender e responder aos instrumentos. Na etapa 3, participaram 141 pacientes com esquizofrenia e 119 controles saudáveis com idades entre 18 e 60 anos, avaliados em MT, velocidade de processamento (VP) e funcionalidade. Resultados Os resultados revelaram bons índices de consistência interna para ambas as medidas desenvolvidas, tanto para a amostra total como para cada grupo separadamente, bem como evidências de validade convergente com medidas de MT, validade discriminante com medidas de VP e sensibilidade para discriminar o desempenho entre os grupos. Análise de componentes principais revelou que os testes de atualização apresentaram altas cargas e um fator separado das medidas de VP. Relações positivas, significativas, porém baixas, foram encontradas com medidas de funcionalidade. Conclusão Esses resultados fornecem bons parâmetros psicométricos para as medidas desenvolvidas, aplicáveis em contextos de pesquisa cognitiva da esquizofrenia.

Novas possibilidades na avaliação neuropsicológica dos transtornos invasivos do desenvolvimento: análise dos movimentos oculares / New possibilities on neuropsychological assessment in pervasive developmental disorders: analyses of eye movements

O presente trabalho teve por objetivo utilizar o rastreamento ocular como parte da avaliação neuropsicológica em crianças e jovens com TID. Foram avaliadas 10 crianças e jovens com diagnóstico clínico de TID, idade média 11,9 (DP=3,22). Todas as crianças foram pareadas por idade e sexo com um grupo controle. Avaliou-se a inteligência com o WISC III e o rastreamento ocular com Tarefa de Sacada Preditiva (SP) e Tarefa de Anti-Sacada (AS). Encontraram-se diferenças significativas para acertos, erros e latência para Tarefa SP; e erros seguidos de acerto para Tarefa AS. Resultados indicam falta de regulação da atenção voluntária, dificuldade em inibir um comportamento e direcioná-lo ao objetivo proposto na tarefa, alteração no planejamento de ação e dificuldade para iniciação de resposta no grupo TID. Todas as alterações encontradas corroboram dados da literatura. Conclui-se que a avaliação dos movimentos oculares contribui para a avaliação neuropsicológica, assim como para intervenções eficazes nos TID.

The objective of the present study is to use eye tracking in neuropsychological assessment of PDD children and adolescents. Ten clinically diagnosed PDD children and adolescents, mean age 11,9 (SD=3,22), were assessed. All children were pared by age and gender with a control group. The WISC III was used to assess intelligence and the eye movements parameters were assessed with Predictive Saccade Task (SP) and Anti-Saccade Task (AS). Significant differences between groups were found in the eye tracking tasks accuracy, errors and latency in the SP Task; and errors followed by correct responses in the AS Task. Results show lack on voluntary attention regulation, response inhibition, planning, and response initiation on the PDD group. All the differences corroborate previous literature. In conclusion, the assessment of eye movements in PDD children contributes to neuropsychological assessment, as well as to development of efficient interventions.