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1.
Brain ; 146(1): 167-181, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36574957

RESUMO

Fluid intelligence is arguably the defining feature of human cognition. Yet the nature of its relationship with the brain remains a contentious topic. Influential proposals drawing primarily on functional imaging data have implicated 'multiple demand' frontoparietal and more widely distributed cortical networks, but extant lesion-deficit studies with greater causal power are almost all small, methodologically constrained, and inconclusive. The task demands large samples of patients, comprehensive investigation of performance, fine-grained anatomical mapping, and robust lesion-deficit inference, yet to be brought to bear on it. We assessed 165 healthy controls and 227 frontal or non-frontal patients with unilateral brain lesions on the best-established test of fluid intelligence, Raven's Advanced Progressive Matrices, employing an array of lesion-deficit inferential models responsive to the potentially distributed nature of fluid intelligence. Non-parametric Bayesian stochastic block models were used to reveal the community structure of lesion deficit networks, disentangling functional from confounding pathological distributed effects. Impaired performance was confined to patients with frontal lesions [F(2,387) = 18.491; P < 0.001; frontal worse than non-frontal and healthy participants P < 0.01, P <0.001], more marked on the right than left [F(4,385) = 12.237; P < 0.001; right worse than left and healthy participants P < 0.01, P < 0.001]. Patients with non-frontal lesions were indistinguishable from controls and showed no modulation by laterality. Neither the presence nor the extent of multiple demand network involvement affected performance. Both conventional network-based statistics and non-parametric Bayesian stochastic block modelling heavily implicated the right frontal lobe. Crucially, this localization was confirmed on explicitly disentangling functional from pathology-driven effects within a layered stochastic block model, prominently highlighting a right frontal network involving middle and inferior frontal gyrus, pre- and post-central gyri, with a weak contribution from right superior parietal lobule. Similar results were obtained with standard lesion-deficit analyses. Our study represents the first large-scale investigation of the distributed neural substrates of fluid intelligence in the focally injured brain. Combining novel graph-based lesion-deficit mapping with detailed investigation of cognitive performance in a large sample of patients provides crucial information about the neural basis of intelligence. Our findings indicate that a set of predominantly right frontal regions, rather than a more widely distributed network, is critical to the high-level functions involved in fluid intelligence. Further they suggest that Raven's Advanced Progressive Matrices is a useful clinical index of fluid intelligence and a sensitive marker of right frontal lobe dysfunction.


Assuntos
Encéfalo , Inteligência , Humanos , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Cognição , Córtex Pré-Frontal , Lobo Frontal/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética , Testes Neuropsicológicos
2.
Neuropsychol Rehabil ; 28(2): 208-222, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29108479

RESUMO

Impaired time perception is considered to be a relatively unusual and poorly understood consequence of brain injury. This paper presents a case study of altered time perception in JB, a 50-year-old woman who in 2011 had a small thalamic stroke affecting the right anteromedian region. We report on her subjective experience and present results from studies of retrospective timing (i.e., estimating how much time has passed and the clock time) and prospective timing (i.e., producing and reproducing intervals). The results showed that relative to neurologically healthy and brain-injured controls, JB had impaired retrospective timing and impaired prospective time reproduction. However, her prospective time production did not differ significantly from either of the control groups. We interpret this to mean that JB's essential timing functions are intact, and that rather, her time perception impairment stems from a problem in anterograde memory for time intervals. Further, we argue that unlike other cognitive domains, time perception alteration is neither anticipated nor evaluated in most patients, yet these impairments can have a remarkably serious impact on daily life. We encourage further investigation of this topic.


Assuntos
Infarto Encefálico/psicologia , Acidente Vascular Cerebral/psicologia , Tálamo/patologia , Percepção do Tempo , Infarto Encefálico/complicações , Infarto Encefálico/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/patologia , Tálamo/diagnóstico por imagem
3.
BMC Psychiatry ; 17(1): 217, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28606061

RESUMO

BACKGROUND: In preparation for a randomized controlled trial, a pilot study was conducted to investigate the feasibility, acceptability and effectiveness of a psychotherapy group based on metacognitive-oriented social skills training (MOSST). METHODS: Twelve outpatients with schizophrenia were offered 16 group-sessions of MOSST. Effect sizes were calculated for changes from baseline to treatment end for both psychosocial functioning and metacognitive abilities measured by the Personal and Social Performance Scale (PSP) and the Metacognition Assessment Scale-Abbreviated (MAS-A) respectively. RESULTS AND DISCUSSION: Ten patients finished the full treatment protocol and nonsignificant moderate effect sizes were obtained on PSP and MAS-A scores. To date, this is the first study in Spain to suggest that outpatients with schizophrenia will accept metacognitive therapy for social skills training and evidence improvements in psychosocial functioning and metacognition. CONCLUSION: Despite limitations inherent in a pilot study, including a small sample size and the absence of a control group, sufficient evidence of effectiveness was found to warrant further investigation. TRIAL REGISTRATION: ISRCTN10917911 . Retrospectively registered 30 November 2016.


Assuntos
Metacognição , Esquizofrenia/terapia , Habilidades Sociais , Adulto , Protocolos Clínicos , Feminino , Humanos , Masculino , Pacientes Ambulatoriais , Projetos Piloto , Psicologia do Esquizofrênico , Espanha
4.
J Neuropsychol ; 17(2): 417-429, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36808478

RESUMO

Raven's Advanced Progressive Matrices (APM) Set I is a validated and brief test of fluid intelligence, ideal for use in busy clinical settings. However, there is a dearth of normative data allowing an accurate interpretation of APM scores. To address this, we present normative data from across the adult lifespan (18-89 years) for the APM Set I. Data are presented in five age cohorts (total N = 352), including two older adult cohorts (65-79 years and 80-89 years), which allows age-standardized assessment. We also present data from a validated measure of premorbid intellectual ability, which was absent from previous standardizations of longer forms of the APM. In line with previous findings, a striking age-related decline was noted, beginning relatively early in adulthood and most marked amongst lower-scoring individuals. Older adults did not demonstrate difficulty with specific test items or make an increased proportion of specific errors. Sex was not a significant predictor of performance. The data set is of particular use in the neuropsychological assessment of older adults, given the known susceptibility of fluid intelligence to both the effects of normal ageing and acquired brain injury in older age. The results are discussed in light of theories of neurological ageing.


Assuntos
Inteligência , Longevidade , Humanos , Idoso , Testes de Inteligência , Envelhecimento , Cognição
5.
Brain Commun ; 5(6): fcad318, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38046096

RESUMO

Though phonemic fluency tasks are traditionally indexed by the number of correct responses, the underlying disorder may shape the specific choice of words-both correct and erroneous. We report the first comprehensive qualitative analysis of incorrect and correct words generated on the phonemic ('S') fluency test, in a large sample of patients (n = 239) with focal, unilateral frontal or posterior lesions and healthy controls (n = 136). We conducted detailed qualitative analyses of the single words generated in the phonemic fluency task using categorical descriptions for different types of errors, low-frequency words and clustering/switching. We further analysed patients' and healthy controls' entire sequences of words by employing stochastic block modelling of Generative Pretrained Transformer 3-based deep language representations. We conducted predictive modelling to investigate whether deep language representations of word sequences improved the accuracy of detecting the presence of frontal lesions using the phonemic fluency test. Our qualitative analyses of the single words generated revealed several novel findings. For the different types of errors analysed, we found a non-lateralized frontal effect for profanities, left frontal effects for proper nouns and permutations and a left posterior effect for perseverations. For correct words, we found a left frontal effect for low-frequency words. Our novel large language model-based approach found five distinct communities whose varied word selection patterns reflected characteristic demographic and clinical features. Predictive modelling showed that a model based on Generative Pretrained Transformer 3-derived word sequence representations predicted the presence of frontal lesions with greater fidelity than models of native features. Our study reveals a characteristic pattern of phonemic fluency responses produced by patients with frontal lesions. These findings demonstrate the significant inferential and diagnostic value of characterizing qualitative features of phonemic fluency performance with large language models and stochastic block modelling.

6.
Brain Commun ; 3(4): fcab232, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34693285

RESUMO

The voluntary generation of non-overlearned responses is usually assessed with phonemic fluency. Like most frontal tasks, it draws upon different complex processes and systems whose precise nature is still incompletely understood. Many claimed aspects regarding the pattern of phonemic fluency performance and its underlying anatomy remain controversial. Major limitations of past investigations include small sample size, scant analysis of phonemic output and methodologically insufficient lesion analysis approaches. We investigated a large number of patients with focal unilateral right or left frontal (n = 110) or posterior (n = 100) or subcortical (n = 65) lesions imaged with magnetic resonance or computed tomography and compared their performance on the number of overall responses, words produced over time, extremely infrequent/unknown words and inappropriate words generated. We also employed, for the first time parcel-based lesion-symptom mapping, tract-wise statistical analysis as well as Bayesian multi-variate analysis based on meta-analytically defined functional region of interest, including their interactions. We found that left frontal damage was associated with greater impairment than right frontal or posterior damage on overall fluency performance, suggesting that phonemic fluency shows specificity to frontal lesions. We also found that subcorticals, similar to frontals, performed significantly worse than posteriors on overall performance suggesting that subcortical regions are also involved. However, only frontal effects were found for words produced over time, extremely infrequent/unknown and inappropriate words. Parcel-based lesion-symptom mapping analysis found that worse fluency performance was associated with damage to the posterior segment of the left frontal middle and superior gyrus, the left dorsal anterior cingulate gyrus and caudate nucleus. Tract-wise statistical analysis revealed that disconnections of left frontal tracts are critical. Bayesian multi-variate models of lesions and disconnectome maps implicated left middle and inferior frontal and left dorsomedial frontal regions. Our study suggests that a set of well localized left frontal areas together with subcortical regions and several left frontal tracts are critical for word generation. We speculate that a left lateralized network exists. It involves medial, frontal regions supporting the process of 'energization', which sustains activation for the duration of the task and middle and inferior frontal regions concerned with 'selection', required due to the competition produced by associated stored words, respectively. The methodology adopted represents a promising and empirically robust approach in furthering our understanding of the neurocognitive architecture underpinning executive processes.

7.
Schizophr Bull ; 44(6): 1235-1244, 2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-29267940

RESUMO

A pilot study of the effects of metacognition-oriented social skills training (MOSST) on social functioning in patients with schizophrenia spectrum disorders (SSDs) reported promising results. The main purpose of the current trial was to compare the effectiveness and potential benefits of MOSST vs conventional social skills training (SST). Single-blind randomized controlled trial with 2 groups of patients aged 18-65 with SSDs on partial hospitalization. Participants were randomly assigned (1:1) to receive 16 group sessions with MOSST or conventional SST, both in addition to standard care, over 4 months, with a 6-month follow-up. Psychosocial functioning, metacognition, and symptom outcomes were measured by blind assessors. Statistical analyses used mixed models to estimate treatment effects in each postrandomization time point. Thirty-six patients were randomly assigned to the MOSST group and 33 patients to the conventional SST group. Between-group differences were significant in favor of MOSST on Social and Occupational Functioning Assessment Scale (SOFAS) and Personal and Social Performance Scale (PSP) total scores at post-treatment and follow-up. Concerning PSP subscales, there were significant between-group differences in favor of MOSST at follow-up on socially useful activities, personal and social relationships, and disturbing and aggressive behaviors. Metacognition only improved following MOSST group. For people with SDDs, MOSST appears to have short- and long-term beneficial effects on social functioning and symptoms. Further studies are required to replicate the current results in other samples.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Remediação Cognitiva/métodos , Relações Interpessoais , Metacognição/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Esquizofrenia/terapia , Habilidades Sociais , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Adulto Jovem
9.
Front Psychol ; 6: 465, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25954224

RESUMO

The aim of this study was to analyse the psychometric properties of the Spanish NEO Five Factor Inventory-Revised (NEO-FFI-R) using Rasch analyses, in order to test its rating scale functioning, the reliability of scores, internal structure, and differential item functioning (DIF) by gender in a psychiatric sample. The NEO-FFI-R responses of 433 Spanish adults (154 males) with an anxiety disorder as primary diagnosis were analysed using the Rasch model for rating scales. Two intermediate categories of response ('neutral' and 'agree') malfunctioned in the Neuroticism and Conscientiousness scales. In addition, model reliabilities were lower than expected in Agreeableness and Neuroticism, and the item fit values indicated each scale had items that did not achieve moderate to high discrimination on its dimension, particularly in the Agreeableness scale. Concerning unidimensionality, the five NEO-FFI-R scales showed large first components of unexplained variance. Finally, DIF by gender was detected in many items. The results suggest that the scores of the Spanish NEO-FFI-R are unreliable in psychiatric samples and cannot be generalized between males and females, especially in the Openness, Conscientiousness, and Agreeableness scales. Future directions for testing and refinement should be developed before the NEO-FFI-R can be used reliably in clinical samples.

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