Operant Conditioning: a behavior/reward system intervention developed by B.F. Skinner in response to the Classical Conditioning intervention previously put forward by Ivan Pavlov.
OC works by rewarding behavior positively so that such behavior continues to be repeated. The idea is that the motivation involved in the trade process will cement itself strongly enough to connect the expected behavior to something positive. The opposite would be to provide negative reinforcement (punishment, consequences) to try to decrease or extinguish a behavior altogether.
A 1964 study by Frank Hewett "Teaching Reading to an Autistic Boy through Operant Conditioning" published in The Reading Teacher is still used today as a benchmark in the field of education, since it is one of the first and most systematic demonstrations on the use of OC in an autistic child. The gist of the study basically acknowledges that the process of presenting the reward prior to the activity is what instantly triggers the attention of a child that is otherwise out of synch from his or her own environment.
When the reward is introduced, natural curiosity and motivation is most likely to attach the child instantly to a focal point, even if it is the reward itself. The negotiation time when the teacher explains the process of obtaining the reward is golden: the task must be verbalized with clarity using action words, going straight to the point. Action words are less abstract than adjectives, so it makes sense to go to the point and kindly point out the task: "Paint me a picture, please?" "Do you want a reward if you finish?" and as soon as the behavior is complete, reward the student.
For a period of about one week the teacher can decide the rate at which the reward will be given. Granted, the child must show signs of improvement in manipulating the task. Once the task is manipulated and repeated in different scenarios there is no need to reward constantly. Yet, notice how the dynamics during trade time instantly made the child interact with his or her environment, even if just for a limited period of time.
Therefore, OC is an excellent intervention to use with children suffering from autism because it pulls out of them an instant connection caused by motivation. The motivating factor will, in itself, serve as a sustained affective stimulus that may aid the child remain in contact with the environment, until the task is complete and the expected reward is given. The chances of repeating the behavior are much higher this way.