Or, more appropriately, Differential Inhibition

A more complex form of internal inhibition, which was described in Pavlov's fifth lecture. In Pavlov's words:

"A positive conditioned stimulus is firmly established in a dog by means of the usual repetitions with reinforcement. A new stimulus is now occasionally added, and whenever the combination is applied, which may be at intervals sometimes extending to hours or days, it is never accompanied by the unconditioned stimulus. In this way, the combination is gradually rendered ineffective, so that the conditioned stimulus, when applied in combination with the additional stimulus loses its positive effect, although when applied singly and with constant reinforcement it retains its full powers."

Pavlov explained that the term that emerged for this second type of internal inhibition, "Conditioned Inhibition," was a misnomer that simply came about as the experiments progressed. He also explained that, once the distinctions had become clear, his preference would be the more descriptive ("appropriate") term: "differential inhibition."