ABSTRACT
Objective: To test the feasibility and to present preliminary results of a neuroimaging protocol to evaluate adolescent depression in a middle-income setting. Methods: We assessed psychotropic medication-free adolescents (age range 14-16 years) with a diagnosis of major depressive disorder (MDD). Participants underwent a comprehensive clinical evaluation and both structural and functional magnetic resonance imaging (fMRI). In this pilot study, a preliminary single-group analysis of resting-state fMRI (rs-fMRI) data was performed, with a focus on the default mode network (DMN), cognitive control network (CCN), and salience network (SN). Results: The sample included 29 adolescents with MDD (mean age 16.01, SD 0.78) who completed the protocol. Only two participants were excluded due to MRI quality issues (head movement), and were not included in the analyses. The scans showed significant connectivity between the medial prefrontal cortex and posterior cingulate cortex (DMN), the ACC and anterior insula (SN), and the lateral prefrontal cortex and dorsal parietal cortex (CCN). Conclusion: We demonstrated the feasibility of implementing a complex neuroimaging protocol in a middle-income country. Further, our preliminary rs-fMRI data revealed patterns of resting-state connectivity consistent with prior research performed in adolescents from high-income countries.
Subject(s)
Humans , Male , Adolescent , Magnetic Resonance Imaging/methods , Depressive Disorder, Major/diagnostic imaging , Neuroimaging/methods , Quality Control , Socioeconomic Factors , Brazil , Cerebral Cortex/diagnostic imaging , Feasibility Studies , Surveys and Questionnaires , Reproducibility of Results , Depressive Disorder, Major/physiopathology , Neural Pathways , Neuropsychological TestsABSTRACT
PURPOSE: To identify brain dominance for language functions with DLT and correlate these results with those obtained from fMRI in patients suffering from intractable temporal lobe epilepsy. METHOD: This study reports on 13 patients who underwent pre-surgical epileptic evaluation between April and October 2004 at the Epilepsy Surgery Program, Hospital Sao Lucas, PUCRS. In DLT, dominance was assessed through a consonant-vowel task, whereas in fMRI patients performed a verb generation task. RESULTS: Our results identified a correlation between the fMRI lateralization index and the DLT ear predominance index and reply difference index (r=0.6, p=0.02; Pearson Correlation Coefficient), showing positive correlation between results obtained from fMRI and DLT. CONCLUSION: DLT was found to significantly correlate with fMRI. These findings indicate that DLT (a non-invasive procedure) could be a useful tool to evaluate language brain dominance in pre-surgical epileptic patients as it is cheaper to perform than fMRI.
OBJETIVO: Identificar a dominância cerebral para funções de linguagem através do teste de escuta dicótica (TED) e correlacionar com os resultados de ressonância magnética funcional (RMf) em pacientes com epilepsia refratária de lobo temporal. MÉTODO: Foram estudados 13 pacientes com epilepsia refratária de lobo temporal, que realizaram avaliações pré-cirúrgicas no período de abril a outubro de 2004 no Programa de Cirurgia de Epilepsia do Hospital São Lucas da PUCRS. Realizada investigação da dominância hemisférica para linguagem através do TED Consoante-Vogal e da RMf pela geração de verbos. RESULTADOS: Verificou-se a existência de correlação entre os índices de lateralidade (RMf) e os índices de predomínio de orelha e de diferença de resposta (TED) (r=0,6, p=0,02). CONCLUSÃO: Existe correlação entre os resultados obtidos através da RMf (índice de lateralidade) e do TED (índice de predomínio de orelha e índice de diferença de resposta) em pacientes com epilepsia refratária de lobo temporal.
Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Epilepsy, Temporal Lobe/physiopathology , Functional Laterality/physiology , Language , Dichotic Listening Tests , Diffusion Magnetic Resonance ImagingABSTRACT
OBJETIVO: Identificar as regiões cerebrais responsáveis pelas funções de linguagem através de Ressonância Magnética funcional (RMf) em pacientes com epilepsia refratária de lobo temporal. METODOLOGIA: Foi realizada RMf utilizando-se o paradigma de geração de verbos. Os pacientes ouviam palavras concretas e eram orientados a pensar na sua finalidade, sem verbalizar (ex: faca-cortar). Utilizou-se o cálculo de índice de lateralidade (IL) e a verificação do grau de ativação das áreas classicamente envolvidas na linguagem. RESULTADOS E CONCLUSÕES: Constatou-se que 92,3 por cento dos pacientes investigados apresentaram linguagem em hemisfério esquerdo, e 7,7 por cento, linguagem mista. Observou-se que existe maior freqüência de pacientes com ativação nas regiões de Broca esquerda, Córtex Pré-motor esquerdo, área de Wernicke esquerda e Córtex Auditivo esquerdo.
PURPOSE: The purpose of this study was to identify the brain regions for language functions with the functional Magnetic Resonance Image (fMRI) in patients suffering from intractable temporal lobe epilepsy. METHODS: During fMRI, patients performed a verb-generation task. They heard concrete words through headphones and were asked to think of their utility (e.g. pencil - to write), without verbalizing or making any facial or tongue movements, keeping silent and with eyes shut. A laterality index (LI) was calculated and we verify the brain regions activities for language. RESULTS AND CONCLUSIONS: Our results identified that that 92.3 percent of the patients analyzed by fMRI presented left hemisphere language and 7.7 percent presented mixed language representation. It was observed more patients with activation in left Broca area, left pré-motor cortex, left Wernicke area and left hearing cortex.