Multiparameter Optimized tES for Memory in Aging

Inclusion Criteria: * 50 - 85 y.o. * Endorse good health with no history of mental or physical illness * Willingness to adhere to the study schedule and assessments * Able to read consent document and provide informed consent. * English is a first or primary fluent language. Exclusion Criteria: * Any current psychiatric diagnosis or current Clinical Global Impression ratings of psychiatric illness \> 1 * Neurodevelopmental disorders, history of Central Nervous System (CNS) disease, concussion, overnight hospitalization, or other neurologic sequela, tumors, seizures, meningitis, encephalitis, or abnormal CT or MRI of the brain * Any psychotropic medication is taken within 5 half-lives of procedure time * Any head trauma resulting in loss of consciousness * Visual impairment (except the use of glasses) * Inability to complete cognitive testing * Active participation or plan for enrollment in another evidence-based clinical trial affecting the psychosocial function * Repeated abuse or dependence upon drugs (excluding nicotine and caffeine) or taking medications including stimulants, modafinil, thyroid medication, or steroids * Implanted devices/ferrous metal of any kind * History of seizure or epilepsy, currently taking medications that lower seizure thresholds * Claustrophobia or other conditions that would prevent the MRI assessment. * Pregnancy (or suspected/possible pregnancy or plan to become pregnant in the short term). * Urine Pregnancy Test: If the subject is a woman …