tVNS During Motor Training in Older Adults

The goal of this study is to learn about the effect of applying transcutaneous vagus nerve stimulation (tVNS) during motor training on motor learning in older adults. The main question it aims to answer is whether applying tVNS after successful motor trials (post-success tVNS) will facilitate the rate of motor learning. Participants will be randomly assigned to tVNS or sham group and receive tVNS or sham, respectively, at the outer ear during finger control training sessions. Finger control performance will be tested before and after the training sessions without outer ear stimulation.

Inclusion Criteria: * 65-84 years old across all races, genders, and ethnicities. * Physically and cognitively healthy Exclusion Criteria: * Younger than 65 years old or older than 84 years old * Current or history of cardiac disease * Have an implanted device such as a neurostimulator or cochlear implant * Current or history of tympanic membrane perforation * Have a musculoskeletal issue that prevents hand function (e.g., arthritis) * Have a vision problem not corrected by glasses or contact lenses * Uncorrected auditory impairments * Had a stroke or lesion (including tumor) in the brain * Had a head injury or brain surgery * Suffer from frequent or severe headaches * Had a fainting spell or syncope * Have any metal in the head such as shrapnel, surgical clips, or fragments from welding or metal work * Have any implanted device such as cardiac pacemakers, medical pumps, or intracardiac lines * Had any brain-related conditions (i.e. multiple sclerosis, Parkinson, Alzheimer) * Had any illness that caused brain injury (i.e. meningitis, aneurysm, brain tumor) * Had any head trauma that was associated with a loss of consciousness or diagnosed as a concussion * Being treated for any psychiatric condition (i.e. depression, anxiety, PTSD, schizophrenia) * Suspected of pregnancy * Pregnant * Cognitive status issues as confirmed with the Mini-Mental State Exam (MMSE \