Cortico-visceral interrelationships during periodic activity of the stomach

In chronic experiments on five dogs with stomach fistulas and bipolar electrodes (6-8 pairs) symmetrically implanted in the cranial bones we recorded simultaneously the activity of the stomach balloonographically and the electroencephalogram using the Nikhon Koden encephalograph with automatic analysis of the frequency spectrum within five ranges: 2-4, 4-8, 8-12, 12-20, and 20-30 oscill/sec. The correlation between the frequency spectrum of the EEG and the phases of periodic activity (PA) cycles of the stomach in the form of a regular shift in the predominance of fast (during contraction periods) or slow (during resting periods) components and its changes under the influence of atropine and food stimulants have been described. The EEG complexes typical of periods of contraction or resting are regarded as cortical correlates of the PA under conditions of good adaptation of the animals to the experimental situation. The changes in the correlation under conditions of actions used indicate a firmer association between the PA EEG correlates with other components of the PA rather than with the motor function of the stomach.