Schedules of Reinforcement: When to Use Positive and Negative Reinforcement

We’ve already had an introduction to B.F. Skinner’s operant conditioning theory (see Understanding Reinforcement vs. Punishment), so now it’s time to delve deeper and discuss schedules of reinforcement.  Here we’ll continue to focus on parenting techniques derived from operant conditioning theory (i.e., positive and negative reinforcement) and develop an understanding of how choosing when to use these techniques makes a huge difference in your child’s response.

Disclaimer: These tips get a bit technical.  I suggest skimming them over but not getting too caught up in the terminology.  A take-home point at the bottom that parents of young children not sleeping through the night will find particularly useful.  

There are two categories for reinforcement schedules.  First, a continuous schedule of reinforcement means that every instance of a particular behavior is reinforced.  For example, every time your child eats their veggies at dinner, they get dessert.

Second, a partial schedule of reinforcement means that the behavior is only reinforced some of the time.  In this example, sometimes your child eats their veggies and then gets dessert, but other times no dessert is offered despite eating their veggies.

Which reinforcement schedule is better?  Researching his pigeons and rats, B.F. Skinner discovered what he dubbed the partial reinforcement extinction effect, wherein behaviors that are only partially reinforced (i.e., not every time the behavior occurs) are longer lasting, and less prone to extinction, as he called it.  That’s a relief from a parental perspective because you don’t have to reinforce every single desired behavior to get your children to behave well.  For example, according to this theory, if your child gets dessert every night and you stop that reward, they’ll quickly stop eating their veggies.  In contrast, if you only sometimes give your child dessert and then stop, they’ll continue eating their veggies for a while longer.

Things get a little more complicated when you consider that there are different types of partial reinforcement schedules - four different styles of intermittent (as opposed to continuous) reinforcement.  These four subcategories for partial reinforcement schedules are ratio, interval, fixed, and variable.  If the schedule is developed based on the frequency of a behavior, it is called a ratio schedule.  If a schedule is developed based on the amount of time that has elapsed, it is called an interval schedule. 

Bear with me; these concepts will be critical later when I review sleep training techniques like the Ferber method and the cry it out method.  It’s about to get a little tricky because particular combinations of these subcategories have utility.  We will need a chart to wrap our heads around these concepts.

In a fixed-ratio schedule, your child’s behavior is reinforced after a fixed number of times, like a factory worker who gets paid $10 for every 100 toothpaste caps he puts on a tub of toothpaste.  For children, this might mean that they get a treat every 5 times they eat their veggies.

In a variable-ratio schedule, the number of times a child has to exhibit the behavior to get the reinforcer varies randomly, as with slot machines.  So, if your child eats their veggies today, they get a treat, but they won’t get another treat until they eat their veggies 6 times, and after that, it will be 3 veggie eatings to earn a treat, and so on.

There are still two subcategories to cover.  First, in a fixed-interval schedule, the behavior must be exhibited after a specified amount of time has elapsed before the reinforcer is given.  For example, a student who has a spelling test every Friday engages in the behavior of studying and is rewarded with a good test grade, but only on Fridays.  Studying during the week might help them on Friday, but they only get the reward on Friday.  Back to the dessert example, if your child eats their veggies on Friday, they get dessert, and it’s not dependent on whether they ate their veggies the rest of the week.

In a variable-interval schedule, a varying amount of time must pass between rewarded behaviors, as in pop quizzes.  For a young child, this might mean dessert is offered tonight, again in a week, two days later, and then the next day again.  In this dessert example, the difference between variable-ratio and variable-interval schedules is subtle - the difference is how the reward timing is defined - by the accumulated number of behaviors or by the amount of time that must pass before the one critical behavior that earns the dessert.

Which partial reinforcement schedule is the best?  It depends on what behavior you are trying to change and what you know about your child’s emotional stability and understanding of delayed gratification.  There are some well-researched phenomena to help guide your reward distribution.  Ratio schedules (both fixed or variable) are most likely to increase the frequency of a behavior – the more the child cleans up, the more likely they are to get the treat.  Compared to variable-ratio schedules, in fixed-ratio schedules, you tend to see more of a lull in the desired behavior immediately after the reinforcer is given because the child knows how many times they have to do the desired behavior before earning the next treat.  In fixed-interval schedules (like the spelling test), you tend to see long periods without the desired behavior (studying) and then a surge of behavior before the end of the interval (the test).  Variable-interval schedules tend to result in consistent patterns of behavior where you study regularly just in case there’s a pop quiz tomorrow.  

From a parental perspective, implement a ratio schedule if you want to see change fast.  If you want to train your child to be consistent in their behavior, variable schedules, whether ratio or interval, are better than fixed schedules – keep them on their toes!  Variable schedules are also harder to extinguish, meaning your child will keep up the good behavior for a longer time than with fixed schedules, even if you remove the reinforcer.  

If you’re a psychology nut like me, this is fascinating, though a little tricky to wrap your head around.  So don’t worry if you got lost in the details of this lesson.  This is probably the most complicated of all my psychology-based tips.  The parenting applications are numerous, but the most helpful knowledge is this: Reward your children at fixed intervals or fast change; reward them intermittently (like a slot machine) to promote consistent behavior. 

The main reason I’m covering these details is to provide the background needed when I discuss sleep training your child using a cry it out method.  Knowing about the partial reinforcement extinction effect, you now understand that intermittently checking in on your child at night during sleep training is a form of partial reinforcement.  By checking in on your child, you’re reinforcing their crying behavior and making it harder for them to extinguish that behavior and learn to self-soothe at night.  You can speed up sleep training by restraining yourself from checking in on your child.  

Operant conditioning is part of the Consequences category in my 5 C’s parenting framework (see The 5 C’s to Amazing Parenting).  To find more posts in this category, use the category search menu on the right of the screen.  Keep up the good work on your amazing parenting journey!

P.S. For a step-by-step guide to sleep training your infant or toddler, be sure to check out my Masterclass: Sleep Training.  It provides all the information you need to know to feel confident about your plan to sleep-train your child and to set yourself up for success by making preparations to help the process go as smoothly as possible.  You and your little one will be getting a full n sleep soon with these valuable tips!

You’ll also want to check out my Treasures - Sleep Training page for a select group of products designed to simplify the sleep training process for parents and children.