Effects of taVNS on Fibromyalgia Pain

Inclusion Criteria: 1. Older than 18 years old. 2. Diagnosis of FM pain according to the American College of Rheumatology (ACR) 2010 criteria (existing pain for more than six months with an average of at least 3 on a 0-10 VAS scale). 3. must have the ability to feel sensation by Von-Frey fiber on the forearm. 4. Able to provide informed consent to participate in the study. Exclusion Criteria: 1. Subjects who have unstable medical conditions (e.g., uncontrolled diabetes, uncompensated cardiac issues, heart failure, or chronic obstructive pulmonary disease) or who have functional deficits, as self-reported. 2. history of substance abuse within the past six months as self-reported (if the subject reports a history of substance abuse, we will confirm using the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) criteria). 3. Presence of implanted cranial electronic medical devices (e.g., cochlear implants). 4. pregnancy (as the safety of taVNS in the pregnant population (and children) has not been assessed (though the risk is non-significant), we will exclude pregnant women (and children). Women of child-bearing potential will be required to take a urine pregnancy test during the screening process and every two weeks of stimulation).