Radiological observations of stomach changes accompanying the threat of an injection, and further data on the normal variation of peristaltic rate.

Abstract

1. The interval between peristaltic contractions was recorded for 61 people during a single period of several minutes. These records are combined with a previous series of 17 cases, and the data for the whole of 78 cases are presented. The mean interval for this sample was found to be 20·5 sec. with a standard deviation of 2·59 sec. 2. Forty-six people were subjected to a threat of an injection lasting 1–2 min. during the observation and recording of peristalsis. In about 50 per cent. of these a change in peristalsis occurred during the period of threat. The change consisted either in a cessation of peristalsis for from 69 sec. to over 250 sec. (9 persons), or in the peristalsis becoming much shallower (14 persons). 3. These changes are compared to those that were previously observed to follow an unexpected gun-shot. The proportion of people showing any change is not different in the two groups, but the proportion in whom cessation of peristalsis occurred is greater following the gun-shot stimulus. The pe...