Students sometimes ask what the difference between an establishing operation and a discriminative stimulus is.
These are both very important concepts in behavior modification and it is important to fully understand the differences. What might initially be a source of confusion is that both establishing operations and discriminative stimuli are antecedents (A) to a behavior (B). He are some informal definitions of the two.
Establishing operations work by changing the reinforcement properties of a reinforcer. If a reinforcer is made to be more reinforcing, the consequence will be more desirable which should have a greater effect on eliciting the target behavior. Establishing operations for reinforcers make us want something more that we might have.
Discriminative stimuli work by telling us what behaviors will get reinforced or punished. In this way discriminative stimuli control our behavior and tell us what to do or how to act. When we reliably and predictably change our behavior in the presence of a discriminative stimulus we are said to be under stimulus control.