https://docs.google.com/spreadsheets/d/1jUrBFxUs57HBCj-y0NkID1kzdnsLPpr9/edit#gid=788062431 Mild cognitive impairment (MCI) refers to the transition state between the cognitive changes of normal aging and early dementia, but it does not notably interfere with activities of daily living. MCI is believed to be a prodromal stage of dementia that causes severe cognitive dysfunction, so its identification for early intervention is considered an important therapeutic strategy. In this context, non-pharmacological interventions, such as Transcranial Direct Current Stimulation (tDCS), which uses direct electrical currents to stimulate specific parts of the brain, have been used to clinically improve these patients. Biochemical processes have been linked to the pathogenesis of MCI and dementia, including chronic inflammation, dysregulation of membrane lipids, disruption of neurotransmitter pathways, and mutations in specific genes. Therefore, the general objective of this study is to evaluate the inflammatory and gene expression profile of patients with MCI, responders and non-responders to tDCS. This is a randomized, double-blind, sham-controlled clinical trial (ClinicalTrials.org: NCT04934423). Neuropsychological tests and a sociodemographic and clinical questionnaire will be used to assess and characterize the subjects. Participants captured by the Laboratory of Studies in Aging and Neurosciences of the Federal University of Paraíba will be divided into 02 groups, each with 25 patients, totaling 50 volunteers: Active – participants who will receive real anodic current; Sham – participants who will receive simulated stimulation. Participants enrolled by eligibility criteria will be randomly allocated in a simple 1:1 ratio. The equipment parameters will be customized by Computational Modeling with the help of the Non-Invasive Brain Stimulation Simulation Program and the measurement of the head circumference. The electroencephalogram and the evaluation of polymorphisms of the genes Alpha synuclein and Neuroregulin, as well as the inflammatory mediators IL-6, Il-10 and TNF-α, will be considered as possible predictors of response. The project was evaluated by the Research Ethics Committee of the Federal University of Paraíba, obtaining the following CAAE registration: 40675220.0.0000.5188. It is expected to find improvements in the scores of general cognition and memory tests after the intervention protocol of neurostimulation with an individual dose in the group that will receive the active current, compared to the simulated neurostimulation group. As well as finding differences in the Inflammatory and Genetic profiles of those responders and non-responders to Neurostimulation.