A therapist treating an individual with a conversion disorder works to reduce pleasurable outcomes associated with being sick, while increasing pleasurable outcomes associated with being well. This technique is called:

Reinforcement.

Explanation:

Reinforcement plays a significant role in the learning process of an individual as evident from the process of operant conditioning. As described by the psychologist B. F. Skinner, reinforcement increases the likelihood of a particular behavior. Four forms of reinforcement exist that includes constructive, negative, punishment, and extinction.