Effect of Transcranial Alternating Current Stimulation(tACS) for Early Alzheimer's Disease

This study is testing whether transcranial alternating current stimulation (tACS) — a gentle, non-invasive brain stimulation technique using a mild electrical current applied to the scalp — can improve memory and thinking in patients with early Alzheimer's disease or related conditions who are already taking standard medication. **You may be eligible if...** - You have been diagnosed with early Alzheimer's disease or a related cognitive condition - Your cognitive test scores fall in the mild impairment to early dementia range (MMSE score 10–27) - You have been taking a cholinesterase inhibitor medication (like donepezil) for at least 3 months - Any other psychiatric medications you take have been at a stable dose for at least 3 months **You may NOT be eligible if...** - Your dementia is at a more advanced stage (CDR score above 2) - You have a history of severe psychiatric illness, seizures, or unexplained loss of consciousness - You have a pacemaker, deep brain stimulator, or medication pump implanted in your body - You have had a stroke or other neurological brain disease - You have had a substance abuse problem in the past 6 months Talk to your doctor to see if this trial is right for you.