Non-invasive Markers of Esophageal Function in Adults

The investigator proposes to study electrical activity reflective of esophageal motility in adults noninvasively by the use of multichannel electroesophagogram (EESG) and magnetoesophagogram (MESG) recordings.

Inclusion Criteria: * Adults ≥ 18 years of age who are undergoing HRM for routine standard of care evaluation for esophageal motility. * Normal control participants (ages ≥ 18 years) who have no known gastrointestinal complications. Exclusion Criteria: * Those with claustrophobia who cannot lie still under the SQUID for the length of time required * Due to interference with signal acquisition, subjects with contraindication to undergoing an MRI scan as noted in the MRI Safety checklist by Vanderbilt University Medical Center (such as with heart pacemakers, metal implants, or metal chips or clips) will not undergo SQUID, but can still be eligible to do cutaneous EESG. * Morbid obesity (these patients are potentially unable to lie under the current generation of SQUID devices) * Patients with a history of cardiac arrhythmias or taking anticoagulants will be excluded