Positive Reinforcement Training for Eugene

Positive Reinforcement Training (PRT) is part of operant learning and is used in many different settings to teach performance of several different kinds of behaviors. The underlying process is that the student learns to associate a behavior with a positive reinforcement which is a reward. The reinforcement is food and the sound is called a bridge. The bridge signals that food is coming. The student first learns the association with the sound together with the food, so the sound alone becomes a positive reinforcement. If you’ve ever heard of Pavlov’s dog salivating to the ring of a bell, this is the same thing; classical conditioning.

Timing is Everything in Positive Reinforcement Training

The reinforcement has to occur at the exact time that the behavior occurs. It’s easier for the trainer to whistle than to get the food out. A moment’s delay could mean that the exact behavior is not reinforced. The student hears the bridge when she performs the behavior thus the behavior is reinforced and should increase. The behaviors are simple, such as tolerating a hand close by or more complex actions like presenting an arm. A student learns simple behaviors in a progression to complex behaviors. Tolerating a hand nearby is a precursor to a hand with a syringe. A hand with a syringe is a precursor to a syringe touching the skin. The progressions continue until it is an injection. It has great application for compliance with medical procedures.

In the first video sequence with Eugene (above), Margaret is pairing the sound of the whistle with delivery of food. This is where Eugene learns the whistle is a reward, since it signals the delivery of food. In the next segment he is rewarded for staying still while Margaret holds her hand close to Eugue. In the final segment Eugene is rewarded for staying still while Margaret holds a syringe close to Eugene.

Eugene Is a Model Student

To receive an injection Eugene has to tolerate a syringe touching him. He also has to be in the correct position. This was another behavior that Margaret began shaping. We created an alley and Eugene was reinforced for standing in it.\

This sequence shows Eugene in the alley with his side toward the fencing.

This is a big step for Eugene, usually he sits with his chest and face oriented toward the front of the enclosure. As the training progressed the alley became more narrow and Eugene came closer to the front of the enclosure. By the end of the week he was flush against the fencing. This is the position we need for him to receive the injection.

Eugene has been a star student with his Positive Reinforcement Training. He had several sessions per day while Margaret was here. His urinary problems have been up and down this week and causing varying levels of pain. On the less-pain-days he played “the game” eagerly. But on the more-pain-days he didn’t play as much.  Of course, we gave him a break as he indicated he had had enough. None of the residents are forced to comply. They are never separated from each other, and they are not deprived of food to comply. If they walk away from the session, we invite them to come back once or twice, and after that we end the training and continue with our usual interaction. Margaret intensely trained three of Eugene’s caregivers and she has passed the training onto them. They will continue to shape his behaviors.

Unfortunately, there is a downside to Positive Reinforcement Training as it is used to shape behaviors in less favourable situations. For example, this is how dolphins are trained to perform in shows. At Fauna we feel it is important that PRT not replace the myriad interactions that occur, such as grooming, chase, coloring, or looking through a magazine. We have evidence that both types of interactions, with PRT or without PRT, are equally interesting to the chimpanzees.