Nervous System Responses to Gastrointestinal Challenges

Eligibility Details: Inclusion Criteria 1. Male or female. 2. Age 20-49 years old. 3. Healthy volunteer or established diagnosis of idiopathic gastroparesis as per AGA (American Gastroenterology Association) guidelines. 4. Participant is capable of giving informed consent. 5. Gastroparesis patients must be on stable doses of medications for gastroparesis for preceding 4 weeks prior to enrollment (including cholinergics, anti-cholinergics, dopamine and serotonin receptor agonists/antagonists, motility agents, neuromodulators, herbals). Exclusion criteria. 1. Diagnosis of systemic autonomic nerve dysfunction (i.e. POTS, CAN). 2. Surgical-related gastroparesis 3. Extrinsic myopathy or neuropathy causing gastroparesis. 4. Use of narcotic pain medications in the preceding 2 weeks of study enrollment. 5. Patients with enteric feeding tubes or requiring parenteral nutrition. 6. Patients with severe disease flare requiring hospitalization or frequent emergency room visits (last within 3 months or less of enrollment). 7. Untreated significant depression or suicidal thoughts. 8. Pregnant or breast-feeding women. 9. History of gastric pacemaker implantation. 10. Patients with prior gastric surgery, including fundoplication, partial/total gastrectomy, pyloroplasty, or gastric bypass. 11. Patients with implantable electronic devices. 12. Dairy, wheat, or egg allergy/intolerance. 13. Allergy to commercial clinical adhesive for EKG stickers. 14. Non-English speaker and/or hearing impaired (as participants need to follow English verbal commands and cues for the experiment).