Funções executivas, metacognição, regulação emocional e neuromodulação em adultos com e sem depressão

Abstract

The objective of this thesis was to evaluate the correlation and prediction between components of executive functions (inhibitory control and cognitive flexibility), metacognition of thoughts and feelings, and emotional regulation in typical adults. Additionally, the present study aimed to evaluate the effects of transcranial direct current stimulation (tDCS) on the main dependent variables of the study, in adults with major depression. The thesis is divided into three empirical studies. The first article described the construction of the Metacognition of Thoughts and Feelings Scale (EMETAPS) and analyzed the validity evidence based on content and internal structure. Participants were 419 adults with typical development, aged between 18 and 60 years. The scale items were constructed based on the Knowledge of Cognition and Regulation of Cognition constructs. According to the judges' analysis, factor analysis and internal consistency results, the EMETAPS proved to be adequate for evaluating the metacognition of thoughts and feelings in typical adults. Study 2 had the general objective of evaluating the correlation and prediction between executive functions, metacognition and emotional regulation in typical adults. 245 adults aged between 18 and 55 answered the Five Digits Test – FDT, the EMETAPS and the Emotion Regulation Questionnaire (ERQ). The results showed that there was no correlation between executive functions and metacognition. On the other hand, results revealed that subcomponents of executive functions and metacognition correlated with different emotion regulation strategies. Study 3 examined the effects of tDCS on the dorsolateral prefrontal cortex (DLPFC) on executive functions, metacognition of thoughts and feelings, and emotion regulation in adults with major depression. Eighteen adults between 18 and 40 years old participated, who underwent 10 sessions of active tDCS (n = 10) or sham tDCS (n = 8) for two weeks. The severity of depression symptoms, executive functions, metacognition, and emotion regulation strategies of participants were assessed at baseline, posttest, and 3-month follow-up after the intervention. Overall, it was possible to observe that active tDCS did not have a greater effect on the variables compared to the SHAM intervention. New research is needed that seeks to assess the underlying mechanisms of emotion regulation, as well as to find the best tDCS intervention protocols capable of promoting a significant improvement in cognitive functions and in emotion regulation strategies in adults with major depression.