Effect of Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) on Plasma Insulin Levels

The vagus or vagal nerve is a nerve that sends signals from the brain to other parts of the body to control involuntary functionm, including stomach function, and it is important to the regulation of insulin, C-peptide, and glucose levels. The purpose of this study is to evaluate whether electrically stimulating the nerve around the external ear will also stimulate the internal vagus nerve and influence the levels of insulin, C-peptide, and glucose. If it does, investigators hope that this will help innovate treatment of patients with nausea, vomiting, and disordered stomach function, and patients with diabetes.