Fig. 1.

A: schematic representation of the event-related experimental paradigm from the phase I studies. Two functional magnetic resonance imaging (fMRI) scans of single-trial swallows were performed before and after esophageal acid perfusion. B: schematic representation of the event-related experimental paradigm from the phase II studies. Two fMRI scans of single-trial swallows were performed before and after esophageal acid perfusion. Various esophageal acid perfusion scenarios were used to simulate physiological reflux events.