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OBJECTIVE: The cingulate gyrus is implicated in the neurobiology of addiction, such as chronic cocaine consumption. Early life stress (ELS) is an important moderator of cocaine use disorder (CUD). Therefore, we investigated the effect of CUD on cingulate cortical thickness and tested whether a history of ELS could influence the effects of CUD. METHODS: Participants aged 18-50 years (78 with CUD due to crack cocaine consumption and 53 healthy controls) underwent magnetic resonance imaging and the cingulate thickness (rostral anterior, caudal anterior, posterior, and isthmus regions) was analysed. The clinical assessment comprised the Childhood Trauma Questionnaire (CTQ) and the Addiction Severity Index. Group comparisons adjusting by sex, age, and education were performed. Mediation models were generated where lifetime cocaine use, CTQ score, and cortical thickness corresponded to the independent variable, intermediary variable, and outcome, respectively. RESULTS: Group comparisons revealed significant differences in six out of eight cingulate cortices, showing lower thickness in the CUD group. Furthermore, years of regular cocaine use was the variable most associated with cingulate thickness. Negative correlations were found between CTQ scores and the isthmus cingulate (right hemisphere), as well as with the rostral anterior cingulate (left hemisphere). In the mediation analysis, we observed a significant negative direct effect of lifetime cocaine use on the isthmus cingulate and an indirect effect of cocaine use mediated by CTQ score. CONCLUSION: Our findings suggest that a history of ELS could aggravate the negative effects of chronic cocaine use on the cingulate gyrus, particularly in the right isthmus cingulate cortex.
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INTRODUÇÃO: O teste de fluência verbal fonológica é uma tarefa neuropsicológica amplamente utilizada em estudos de neuroimagem funcional que analisam os circuitos neurais relevantes para a produção de linguagem. A maioria dos estudos que utilizam a RMf para analisar as áreas cerebrais de maior ativação durante a tarefa de fluência verbal é realizado na língua inglesa. Embora estudos anteriores tenham demonstrado que dependendo da língua falada possa ocorrer diferença de desempenho na tarefa de fluência verbal, ainda não está claro se esta diferença leva a mudanças do padrão de ativação cerebral. Há indícios na literatura que a ativação cerebral regional durante a tarefa de fluência verbal pode variar com o aumento de dificuldade da tarefa, sendo o cíngulo anterior a área cerebral que parece estar envolvida no processo de adaptação ao grau de dificuldade da tarefa. Estudos com sujeitos saudáveis demonstram também a influência de variáveis demográficas, como idade, escolaridade, gênero e classificação socioeconômica no desempenho na produção de palavras, com alguns estudos reportando maior ativação cortical nos homens em comparação às mulheres. OBJETIVOS: Avaliar os efeitos da variação do grau de dificuldade da tarefa de fluência verbal utilizando a técnica de ressonância magnética funcional. Analisar se há correlação entre os dados demográficos e o desempenho na tarefa de fluência verbal. Comparar o padrão de ativação cerebral entre os gêneros. MÉTODOS: Foram incluídos 21 voluntários saudáveis (12 homens), destros e falantes do português do Brasil como primeira língua. Foram colhidos dados sociodemográficos, neuropsicológicos e de desempenho dos voluntários. Comparamos os achados adquiridos através da técnica de ressonância magnética funcional durante a produção de palavras iniciadas com letras classificadas anteriormente como fáceis e difíceis para produzir palavras na língua portuguesa. As imagens foram adquiridas em aparelho de ressonância...
INTRODUCTION: Phonological verbal fluency is a neuropsychological test used in numerous functional neuro imaging studies to allow the assessment of the neural circuits relevant to language production. The majority of studies that use functional magnetic resonance imaging (fMRI) to analyze the cerebral areas with greater activation during the verbal fluency task have been carried out in English. Although there is evidence that the verbal fluency performance varies as a function of the spoken language, it is unclear if this difference is associated with differences in cerebral activation patterns. Added to that, there is neuroimaging evidence that patterns of regional cerebral activation during VF task may vary with task demand. In particular, the anterior cingulate cortex seems critical to the adaptation process to the level of difficult. Studies of healthy individuals have demonstrated the influence of demographic variables, such as age, level of education, gender and socio-economic status, on word production performance, and some authors have shown greater cortical activation in men than in women. OBJECTIVES: To use the fMRI technique to evaluate the effect of varying levels of difficult of verbal fluency task on the brain activation patterns in healthy subjects. To analyze whether there is a significant correlation between demographic variables and verbal fluency performance. To compare cerebral activation patterns between genders. METHODS: We recruited 21 (12 men) right-handed healthy volunteers, having Portuguese as their first language. Demographic, neuropsychological and behavioral data were collected. We compared fMRI data acquired during production of words beginning with letters classified as easy or hard for word production in Portuguese. Images were acquired in 1,5 T magnet through a clustered image acquisition sequence that allowed overt verbal responses to be made in the absence of scanner noise. Data were analyzed through XBAM software...