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.
Mild cognitive impairment (MCI) is a decline in memory and thinking skills that is greater than expected for a person's age but not severe enough to interfere substantially with daily life. Older adults with MCI are at increased risk of developing dementia, and there are currently few effective treatments for the cognitive difficulties it causes. This study tests whether a form of non-invasive brain stimulation called transcranial alternating current stimulation (tACS) can improve thinking and memory in older women with MCI. tACS delivers a weak electrical current that oscillates at a set frequency through electrodes placed on the scalp. In this study the current oscillates at 80 Hz, a frequency in the gamma range, because gamma brain rhythms are involved in memory and attention and are known to be disrupted in MCI and Alzheimer's disease. Thirty older women with MCI are randomly assigned to one of two groups. One group receives active 80 Hz tACS and the other receives sham (placebo) stimulation, in which the device is set up identically but no meaningful current is delivered. Participants and the person delivering the stimulation do not know which group each participant is in. Both groups complete the same set of cognitive tests before and after the stimulation sessions. The tests measure overall cognitive status, planning ability, visuospatial working memory, and reaction speed. The aim is to determine whether active 80 Hz tACS improves cognitive performance more than sham stimulation in this population.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
DOUBLE
Enrollment
30
Transcranial electrical stimulation (tES) is a non-invasive neuromodulation technique that applies low-intensity electrical currents to the scalp to modulate brain activity. It targets specific brain regions to influence neuronal excitability, connectivity, and plasticity, offering potential therapeutic benefits for neurological and psychiatric conditions. tES is portable, cost-effective, and generally well-tolerated, with minimal side effects such as mild tingling or itching at the stimulation site.
Department of Psychology, University of Mohaghegh Ardabili
Ardabil, Iran
Overall cognitive status
The Montreal Cognitive Assessment (MoCA) is a validated screening measure of global cognitive status, scored from 0 to 30, with higher scores indicating better cognition. Change from baseline to the post-intervention assessment is compared between the active 80 Hz tACS and sham groups.
Time frame: Baseline (pre-intervention), week 2 (immediately after the intervention)
Planning and problem-solving - Performance accuracy and reaction time
The Tower of London is a computerized task that assesses executive function, specifically planning and problem-solving. Higher scores indicate better planning ability. Change from baseline to the post-intervention assessment is compared between the active 80 Hz tACS and sham groups.
Time frame: Baseline (pre-intervention), week 2 (immediately after the intervention)
Spatial working memory - Performance accuracy and reaction time
The Corsi Block-Tapping Test is a computerized task that assesses visuospatial short-term and working memory. Participants reproduce sequences of illuminated blocks of increasing length. Higher scores indicate greater visuospatial working memory capacity. Change from baseline to the post-intervention assessment is compared between the active 80 Hz tACS and sham groups.
Time frame: Baseline (pre-intervention), week 2 (immediately after the intervention)
Cognitive Reaction time
The simple reaction time task is a computerized measure of psychomotor speed. Participants respond as quickly as possible to a stimulus that appears at unpredictable intervals. Shorter reaction times, measured in milliseconds, indicate faster psychomotor speed. Change from baseline to the post-intervention assessment is compared between the active 80 Hz tACS and sham groups
Time frame: Baseline (pre-intervention), week 2 (immediately after the intervention)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.