This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. HYPOTHESIS(ES): 1) Gastric electrical activity (GEA) propagates in the smooth muscle syncytium of the stomach in regular spatiotemporal patterns. 2) Internal gastric electrical patterns in normal tissue produce regular external gastric magnetic field patterns. 3) Gastric electrical patterns in normal humans produce regular spatiotemporal patterns in multichannel external magnetic field recordings. 4) Gastric dysrhythmias resulting from mechanical uncoupling of the gastric syncytium produce irregular spatiotemporal patterns in recordings of both internal serosal potentials and external magnetic fields. 5) Autonomic disorders known to cause gastric dysrhythmias result in abnormal gastric magnetic field spatiotemporal patterns. 6) Patients w/diabetic gastroparesis exhibit abonormal postprandial gastric magnetic field patterns compared to normal volunteers. SPECIFIC AIMS: 1) Characterize magnetic patterns of GEA in normal human volunteers. 2) Characterize the effect of autonomic disorders on gastric magnetic field patterns. 3) Characterize the magnetic signature of diabetic gastroparesis.