On the other hand, a person may feel an itch although there is no public collateral stimulus, or a person may have pain without any public accompaniment.
A way in which the verbal community brings verbal behavior under the control of private stimuli that has the following features:
A private stimulus
A collateral public stimulus
Reinforcement for a given response contingent upon the presence of the public stimulus
The type of private stimulus
Whether or not there is any causal relationship between the public and private stimulus (they need only be correlated)