Gamma tACS to Improve Cognitive Function in Mild Cognitive Impairment

Mild cognitive impairment (MCI) is a decline in memory and thinking that exceeds normal aging but does not substantially disrupt daily life, and it raises the risk of developing dementia. Effective treatments for its cognitive difficulties are few. This study tests whether transcranial alternating current stimulation (tACS), a non-invasive method that delivers a weak oscillating electrical current through scalp electrodes, can improve thinking and memory in older women with MCI. The current oscillates at 80 Hz, a frequency in the gamma range, because gamma brain rhythms support memory and attention and are disrupted in MCI. Thirty older women with MCI are randomly assigned to receive either active 80 Hz tACS or sham (placebo) stimulation. Participants and the person delivering the stimulation do not know the group assignment. Both groups complete the same cognitive tests before and after the sessions, measuring overall cognitive status, planning, visuospatial working memory, and reaction speed. The aim is to determine whether active 80 Hz tACS improves cognitive performance more than sham stimulation.

Inclusion Criteria: * Female, aged 60 to 75 years * Diagnosis of mild cognitive impairment (MCI) established by a psychiatrist and documented in the patient's medical record * Montreal Cognitive Assessment (MoCA) score between 16 and 22 * Written informed consent to participate in the study * No history of Parkinson's disease, stroke, epilepsy, schizophrenia, or congenital olfactory and gustatory disorders Exclusion Criteria: * Inability to tolerate the adverse effects of the stimulation * Unwillingness to continue the sessions * Absence from more than three intervention sessions