[Correlation between electroencephalogram rhythms and periodic gastric motility in fasting dogs]

The correlation between the frequency EEG spectrum and cycle phases of the gastric periodic motility was studied in the day and evening time in chronic experiments on 2 fasting dogs with chronic stomach fistulas and 8 pairs of silver bipolar electrodes implanted into the cranial bones. Consistent changes were observed in the correlation of rapid and slow EEG components according to each type of the periodic motility, the wave portion with a frequency of 2--8 Hz in the total electrical brain activity being minimum and that with a frequency of 20--30 Hz being maximum in the contraction phases. In the phases of the stomach rest, the correlations were reverse. The total portion of the waves with frequencies of 8--12 and 12--20 Hz changed insignificantly during each cycle. The time course of changes in the frequency EEG spectrum was also studied within each cycle phase. Preliminary verification of a possible role of the interoceptive signals from the contracted stomach in the mechanism of the correlation observed provided negative results.