Increase In Mean Amplitude Research Articles

Deprivation and drug effects on prepyriform cortex electrical activity in rats

Abstract Food deprivation in rats was accompanied by increased mean amplitude of prepyriform cortex electrical activity. Virtually all of the effect was observed in the first 23 hr. Observations at deprivation periods of 47 hr showed no further increments in amplitude. Deprivation-associated increments in electrical activity were observed across several different behaviors. The frequency of high amplitude bursts characteristic of the prepyriform region was not affected by deprivation nor did burst frequency vary in the different behaviors. Administration of Benzedrine to food-deprived rats produced a marked diminution in average electrical amplitude and tended to depress the frequency of high amplitude bursts. The animals in this condition ceased working to obtain food but continued to exhibit exploratory behavior resembling that found during food deprivation. Light doses of barbiturate, on the other hand, increased the average electrical amplitude at the same time rendering the animal inactive. Motivational effects on brain electrical activity do not appear to parallel drug-induced effects, although behavior is similar in the two situations.