Cognitive inhibition of human gastric acid output--studies using telemetric measurements.

In study I subjects had two sessions--one to examine the effects of reading and another to study the effects of relaxation exercises. An incomplete crossover design was used. Subjects (N = 13) decreased mean acid output by 32.2% while reading and 2.5% after relaxation exercises (N = 14). In study II, six subjects each had one session to examine the effects on acid output of a difficult maze-solving task. Mean acid output during maze-solving decreased 52.6% relative to the control period. The results of these two studies suggest that the degree of cognitive involvement is an important factor in the decrease of acid output. A modification of the Heidelberg telemetry equipment was described. It permitted a continuous measure of gastric acid output, was relatively nonaversive to subjects, and minimized the risk of cephalic or gastric phase effects of acid secretion due to the measuring technique. It is recommended as a valuable adjunct for studies designed to change gastric acidity.