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.

Inclusion Criteria: * Healthy Volunteers * Aged 18-70 * Willing to have ECG electrodes placed on their neck and chest areas. * Willing to have electrodes placed in the external ear. * Willing to have an indwelling catheter placed to avoid multiple sticks for blood draw. Exclusion Criteria: * Unable to provide consent. * Diabetes diagnosis per patient report * Having known allergies to adhesive on electrode pads or bandages * Having gastric motility issues as determined by the PI or clinical coordinator. * Taking any medications that may affect gastric motility or cardiac variability, i.e. alpha or beta blockers for hypertension. * Pregnant females * Those unwilling to have the taVNS device placed in their ear. * Those unwilling to consent to a blood draw. * Prisoners