Electrogastrogram

Electrogastrogram (short EGG ) denotes an electrophysiological measurement procedures for gastrointestinal motility. The myoelectric gastric activity is measured by skin electrodes.

For the measurement, an electrode is attached to the stomach, which measure the movements of the stomach muscles. This action currents of the stomach muscles can then be graphed and interpreted. The method operates on the same principle as an electrocardiogram (ECG). The muscular contraction of the stomach is highly dependent on the current emotional states, so the EGG method is an interesting psychosomatic measuring instrument to associate certain emotional states experienced a physical correlate, or vice versa.

The discovery of the EGG

WC Alvarez led in 1922 by the first electrical studies of the stomach. In one subject with extremely thin abdominal wall he put the electrodes on and registered an electrical signal having a frequency of approximately 1/20 Hz, that is, of three cycles per minute ( cycles per minute = cpm) had. In this subject, he could directly watch the contraction of the stomach at the same frequency in addition to the electrical signal. The sinusoidal waves of electrogastrogram gram correlated with the visible gastric contraction. From the observation of Alvarez concluded that the electrical signal measured gastric origin.

The discovery came for 20 years until 1953, largely forgotten.