If behaviors are not increasing, there may be problems with the reinforcers you are offering.  Here are some common problems.

Satiation: The child has had more than enough. It is best to stop before this happens. A good idea is to control the length of the session using a timer, or by counting out a certain number of reinforcers ahead of time and stopping when they are done

Boredom: Have a variety of reinforcers available: Reinforcers can change. One day the child might do anything for a popsicle and the next day they detest popsicles. It’s always a good idea to have an array of possible reinforcers. Letting the child choose avoids the manipulation – where they are purposely misbehaving or not performing to see if you have something better.

Timing delays: there will be a slight time delay between the tag and the delivery of the primary reinforcer. This is desirable because it makes the tag become the salient marker of the behavior. However if the delay is too long and some behavior consistently happens in between, then that inbetween behavior will be reinforced. For example: after the tag, the child could get excited and start kicking her feet. If the treat comes during the kicking, the kicking will be reinforced by the treat instead of her earlier action. You cannot withhold the treat, since you did tag. So give the treat and then re-evaulate to try to give the treat faster or be closer to the child with the treat. In this specific example you could teach the child to put her feet on a target and tag/treat to practice the sequence with still feet. This is something to watch for to avoid teaching something that then needs to be untaught. You may even have to shape the waiting for the treat if it is an ongoing problem.

Superstitious behaviors can occur when the child thinks that the reinforcer is contingent on one behavior, when really it is contingent on something else. For example, the child is looking at a toy and reaching for it at the same time. You are tagging for the looking, but she thinks you are tagging for the reaching. Sometimes you can inadvertently teach a superstitious behavior by tagging one thing while something else is going on, or by delivering the reinforcer in such a way as to reinforce a behavior you didn’t intend. We don’t have time today to go into this in detail. I just wanted to bring it up as something to be aware of.

If you see that desired behaviors are not increasing, and you think you may have a problem with reinforcement, here is a checklist that will help you sort that out.