Using an experimental paradigm this investigation explored whether exposure to psychological stress would produce a significant increase in acid-reflux episodes or modify subjective perceptions of gastro-oesophageal reflux (GOR) symptoms. Forty-two patients presenting with heartburn and acid regurgitation underwent 24-h oesophageal pH monitoring. During the last 90 min of this monitoring period, 21 patients received a psychological stressor, while the remaining participants were randomly assigned to a no-stress control condition. State anxiety and subjective GOR symptom ratings were obtained 1 min pretest, 1 min posttest, and 40 min posttest. Cortisol samples were collected at 10-min intervals. The stressor induced a significant increase in cortisol and state anxiety; however, this was not associated with any increase in reflux. Instead, the experimental group reported a dissociation between objectively measured reflux episodes and subjective symptom ratings. A similar pattern was established for participants who reported greater state anxiety, produced larger cortisol responses, or exhibited certain stress-related personality characteristics. The perception of symptoms in the absence of increased reflux when one is stressed may account for low response rates to traditional treatments. This highlights a need to bridge the gap between psychosomatic research and clinical practice to develop more successful GOR therapies.