 Conditioned reinforcers. Conditioned reinforcers are stimuli that have acquired their reinforcing properties by pairing the neutral stimulus or a neutral stimulus with another stimulus that is reinforcing. For example, the clicker training stuff from Karen Pryor. We could pair that sound with food. Treat. Treat. And that will eventually produce that sound as being a reinforcer. We would then call it a conditioned reinforcer simply because we had to develop that reinforcer. It was not natural.