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Brain Lang ; 191: 9-16, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30731324


The left anterior negativity (LAN) is an ERP component that has been often associated with morphosyntactic processing, but recent reports have questioned whether the LAN effect, in fact, exists. The present project examined whether the LAN effect, observed in the grand average response to local agreement violations, is the result of the overlap between two different ERP effects (N400, P600) at the level of subjects (n = 80), items (n = 120), or trials (n = 6160). By-subject, by-item, and by-trial analyses of the ERP effect between 300 and 500 ms showed a LAN for 55% of the participants, 46% of the items, and 49% of the trials. Many examples of the biphasic LAN-P600 response were observed. Mixed-linear models showed that the LAN effect size was not reduced after accounting for subject variability. The present results suggest that there are cases where the grand average LAN effect represents the brain responses of individual participants, items, and trials.

Encéfalo/fisiologia , Eletroencefalografia/normas , Potenciais Evocados , Linguagem , Adulto , Artefatos , Variação Biológica Individual , Compreensão , Eletroencefalografia/métodos , Feminino , Humanos , Masculino
Neurosci Biobehav Rev ; 51: 31-47, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25614131


Learning a second language (L2) can be crucial in the present globalized society. However, reaching the level of L1 performance of native speakers is still a challenge for many. Distinct factors could account for the persistent gap observed between natives' and non-natives' syntactic abilities: L1-L2 differences, AoA, proficiency, L2 immersion duration, L2 training duration. Although different theoretical approaches described the role of these several factors, not all studies using on-line measures have investigated them comprehensively and consistently. The present work reviews available ERP studies on L2 syntactic analysis in order to establish the relative weight of each factor on the time course of L2 processing. Logistic regression analyses were performed on the presence or absence of ERP effects reported in response to L2 syntactic violations, including all the influential factors as categorical independent variables. The results showed that immersion duration has an influence on the ERP correlates linked to early mechanisms of syntactic processing, while the global proficiency level has an impact on the ERP correlates related to late, language-monitoring activity.

Encéfalo/fisiologia , Potenciais Evocados , Linguística , Multilinguismo , Humanos
Child Neuropsychol ; 21(5): 693-715, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25270117


Dravet syndrome (DS) is an epilepsy of infantile onset, usually related to a mutation in gene sodium channel alpha 1 subunit, that leads to different typological seizures before the first year of life. Although most research has focused on the clinical description of the syndrome, some recent studies have focused on its impact on cognitive development, identifying both motor disorders and visual-processing deficits as basic factors affected in adults and children with DS. In this article, we designed a cross-sectional study to examine the cognitive phenotype of children affected by DS from a neurodevelopmental perspective. We report measures for both basic (auditory perception, visual and phonological processing, motor coordination) and higher order cognitive processes (verbal production, categorization, and executive function) in two age groups of DS children (M = 8.8 and M = 14.1) and control children of the same chronological age. Results showed an important cognitive delay in DS children with respect to controls in both basic and higher order cognitive abilities, with a better general outcome in tasks that required processing visual material (visual memory and categorization) than in tasks involving verbal material. In addition, performance of DS children in certain basic tasks (visual memory) correlated with performance on complex ones (categorization). These findings encourage promoting an early identification of not only clinical but also cognitive features in DS children from very early stages of development in order to optimize their neurodevelopmental outcome.

Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/psicologia , Cognição/fisiologia , Epilepsias Mioclônicas/fisiopatologia , Epilepsias Mioclônicas/psicologia , Adulto , Percepção Auditiva/fisiologia , Estudos de Casos e Controles , Criança , Desenvolvimento Infantil , Transtornos Cognitivos/etiologia , Estudos Transversais , Síndrome de Down , Epilepsias Mioclônicas/complicações , Função Executiva , Feminino , Humanos , Masculino , Memória , Testes Neuropsicológicos , Convulsões
Epilepsy Res ; 108(8): 1326-34, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25048308


The aim of this study was to identify differential global and local brain structural patterns in Dravet Syndrome (DS) patients as compared with a control subject group, using brain morphometry techniques which provide a quantitative whole-brain structural analysis that allows for specific patterns to be generalized across series of individuals. Nine patients with the diagnosis of DS that tested positive for mutation in the SCN1A gene and nine well-matched healthy controls were investigated using voxel brain morphometry (VBM), cortical thickness and cortical gyrification measurements. Global volume reductions of gray matter (GM) and white matter (WM) were related to DS. Local volume reductions corresponding to several white matter regions in brainstem, cerebellum, corpus callosum, corticospinal tracts and association fibers (left inferior fronto-occipital fasciculus and left uncinate fasciculus) were also found. Furthermore, DS showed a reduced cortical folding in the right precentral gyrus. The present findings describe DS-related brain structure abnormalities probably linked to the expression of the SCN1A mutation.

Encéfalo/patologia , Epilepsias Mioclônicas/diagnóstico , Imagem por Ressonância Magnética/métodos , Adolescente , Criança , Epilepsias Mioclônicas/genética , Feminino , Humanos , Masculino , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Tamanho do Órgão , Adulto Jovem
Front Psychol ; 2: 219, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21960979


Cognitive control involves not only the ability to manage competing task demands, but also the ability to adapt task performance during learning. This study investigated how violation-, response-, and feedback-related electrophysiological (EEG) activity changes over time during language learning. Twenty-two Dutch learners of German classified short prepositional phrases presented serially as text. The phrases were initially presented without feedback during a pre-test phase, and then with feedback in a training phase on two separate days spaced 1 week apart. The stimuli included grammatically correct phrases, as well as grammatical violations of gender and declension. Without feedback, participants' classification was near chance and did not improve over trials. During training with feedback, behavioral classification improved and violation responses appeared to both types of violation in the form of a P600. Feedback-related negative and positive components were also present from the first day of training. The results show changes in the electrophysiological responses in concert with improving behavioral discrimination, suggesting that the activity is related to grammar learning.