The interaction between extinctive and supraliminal inhibition

Summary

Interaction between extinctive and supraliminal inhibition was studied on dogs by the method of conditioned salivary reflexes. In extinction of a conditioned reflex to an excessively strong stimulus, there occurs an overstraining of the subliminal inhibition, the sequence of which is: predominance of excitation; disinhibition of the extinction process; and irradiation of excitation to the motor area of the cerebral cortex. The conditioned reflexes in response to stimuli of different strength are arranged by the rate of extinction in the following order: Conditioned reflexes to stimuli of moderate strength are the first to be extinguished; the next are those in response to weak conditioned stimuli, and the last, to excessively strong stimuli. Extinction of conditioned reflexes (Phase 1-the rise of the curve of salivary secretion) was most pronounced in extinction of the reflex to the weak stimulus (light), less pronounced in extinction of the reflex to the moderately strong stimuli (metronome, buzzer, 50-db tone), and very weak or even absent in extinction of the reflex to the excessively strong stimulus (122-db tone).