Body Surface Gastric Mapping to Evaluate Patients With Upper Gastrointestinal Symptoms and Controls

This is an analytical validation observational cohort study is designed to provide evidence of: safety and reliability of Body Surface Gastric Mapping using the Gastric Alimetry System (GAS), normal reference values, and correlation of metrics with patient symptoms among healthy adults and patients diagnosed with upper abdominal motility disorders. GAS is intended to record, store, view and process gastric myoelectrical activity. This is a proprietary system consisting of multiple electrodes arranged on an array that is placed precisely over the stomach, a reader to collect the electrode measurements and a smart tablet application to track patient reported symptoms. Participants meeting inclusion and exclusion criteria will continue fasting for 30 minutes after the Gastric Alimetry System has been applied and begun measuring, eat a standard study meal within 10 minutes and remain quietly seated, reclining, for 4 hours as the GAS continues to collect data. The array is removed and the abdomen is examined for evidence of skin effects.

Inclusion Criteria: Healthy Population: * Adults aged 18 years and over * Able to understand the risks/benefits of the study * Able to give written informed consent * No active gastrointestinal symptoms or pathology * Resides in the Calgary, Alberta area Patient Population: * Adults aged 18 years and over * BMI \> 35 * Able to understand the risks/benefits of the study * Able to give written informed consent * Patients meeting Rome IV Criteria for functional dyspepsia, or a nausea and vomiting disorder * Patients with gastroparesis defined on a standardized gastric scintigraphy study * Resides in the Calgary, Alberta area Exclusion Criteria: Healthy Population: * Under 18 years of age * BMI \> 35 * Taking medications known to affect GI motility or the mid-gut axis (eg antidepressants, anti-anxiety medication, prokinetics, opiates) * Metabolic, neurogenic, or endocrine disorders known to cause gastrointestinal dysmotility (eg. Multiple Sclerosis, Parkinson's disease, hypothyroidism) * Known current GI infection (includes H. pylori when being actively treated) * Known current inflammatory bowel disease * Known current GI malignancy * Known GI functional or motility disorders * Previous gastroduodenal surgery * GI functional or motility disorders * Pregnant women * Open abdominal wounds or abdominal skin not intact (eg rash, abrasions, weeping tissue) * Fragile skin evidence by high susceptibility to skin tears or skin that bruises and breaks easily * Allergy to adhesives * History of allergy or intolerance to ingredients in the meal (nutrient drink, Ensure or similar and Clif bar or similar) * No vulnerable groups such as; prisoners, individuals with known cognitive impairment, or institutionalised individuals be involved * Regular cannabis use * Diagnosed with, or suspected to have life-threatening conditions that could result in immediate danger Patient Population: * Under 18 years of age * BMI \> 35 * Metabolic, neurogenic, or endocrine disorders known to cause gastrointestinal dysmotility (eg. Multiple Sclerosis, Parkinson's disease, hypothyroidism) * Known current GI infection (includes H. pylori when being actively treated) * Known current inflammatory bowel disease * Known current GI malignancy * Previous gastroduodenal surgery * Open abdominal wounds or abdominal skin not intact (eg rash, abrasions, weeping tissue) * Fragile skin evidence by high susceptibility to skin tears or skin that bruises and breaks easily * Allergy to adhesives * Pregnant women * History of allergy or intolerance to ingredients in the meal (nutrient drink, Ensure or similar and Clif bar or similar) * No vulnerable groups such as; prisoners, individuals with known cognitive impairment, or institutionalised individuals be involved * Regular cannabis use except in the case of CHS * Diagnosed with, or suspected to have life-threatening conditions that could result in immediate danger * Inability to remain in a relaxed reclined position for the test duration