David Premack was a professor of psychology at the University of Pennsylvania. In 1959 he published, a theory of reinforcement, later known as “Premack’s Principle.” The theory, which is widely used in behavior therapy, suggests that if a person wants to do a certain activity, they will do a less desired activity to do the preferred activity. In Applied Behavior Analysis, this is often referred to as First/Then because those are the terms typically used. It has also been called Grandma’s Rule because a Grandma might say, “First, eat your vegetables. Then, you can have dessert.” When used correctly, this strategy can improve behavior across multiple settings.
How to Use the Premack Principle
1. Pick an activity that often leads to problem behavior.
For example, if transitioning your child into the bath causes meltdowns or aggressive behaviors, this might be a good behavior to target using the Premack Principle.
2. Pair the less desired activity with a highly desired activity.
For example, if your child enjoys a story before bedtime, use reading a story as the reinforcement for taking a bath.
3. Use consistent, clear, and concise language.
For example, rather than say, “We can read a story after you take your bath.” Say, “First bath, then story.”
4. If they are able, have your child repeat the phrase back to you.
This ensures they have a clear understanding of the expectation.
5. Consider using a visual aid such as a First/Then board to help reinforce the expectation.
This means using a sheet of paper or cardstock, type or write the word “First” on the left side of the page, draw a line down the middle, and type or write the word “Then” on the right side of the page. Use images from a website such as Boardmaker, or print images from photos of the activities you are using for Premack Principle.
6. Praise your child for compliance!
Praise is often the best form of reinforcement. When you give your child praise, the likelihood of them repeating the desired behavior will increase.
Our Family’s Experience
My 5 1/2-year-old son is on the autism spectrum, and we have used the Premack Principle successfully for years, starting when he was only two years old. At that time, he resisted getting his diaper changed. I made a First/Then board with a picture of him getting his diaper changed under the word First and a picture of my cell phone under the word Then, since he loved looking at photos and videos of himself on my phone. I would show him the First/Then board, and verbalize the expectation, before each diaper change. Eventually, he realized that the quicker his diaper was changed, the quicker he’d gain access to seeing the photos and videos. As he got older, we transitioned using the Premack from diaper changes to toilet-training. “First use the potty, then you can use the iPad for x-number of minutes.
At first your child may resist or try to negotiate doing the preferred activity first, but if you are consistent, they will eventually understand the preferred activity comes second.
This easy-to-implement strategy can make huge impacts in helping your child overcome some of their challenging behaviors across almost any setting and might even get them to eat their broccoli!
Children do well if they can. If they can’t, we as adults need to figure out what’s getting in the way and help. – Dr. Ross Greene, The Explosive Child
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