Kinds of reinforcers, Part 3

Revised on 12/22/14

I suggest reading this post after you read the two posts called Kinds of reinforcers, Part 1 and Kinds of reinforcers, Part 2.

On p. 3 Malott tells us that a reinforcer is a stimulus that increases the frequency of a response it follows. Then on p. 4 he tells us that in order for a reinforcer to actually reinforce a particular response that it follows, the reinforcer must be delivered quickly. He says that one second or less is considered immediate reinforcement and up to 60 seconds is considered delayed reinforcement. So here are two more kinds of reinforcers – those that are delivered immediately following a behavior and those that are delayed.

So what about reinforcers that are neither immediate nor delayed? Can’t a reinforcer be delivered more than 60 seconds after a behavior occurs and still reinforce that behavior? Don’t we see this all the time? Suppose I say “Do me this favor and I’ll give you five bucks tomorrow.” Doesn’t the $5 reinforce the behavior of your doing the favor? No. Not according to what Malott says on p. 4.

Does that mean that the $5 is not a reinforcer? No, it doesn’t mean that. Go back to the definition of Reinforcer on p. 3. It’s a stimulus that increases the frequency of a response it follows. There’s nothing in that definition about following the response quickly. If the target behavior (that is, the behavior we’re focused on right now) is your doing me a favor, then if you do it and tomorrow I give you $5, AND (this is very important) you do favors for me more often in the future when I ask you to, then the $5 functions as a reinforcer.

Getting confused? Then read this very carefully or else you’ll get even more confused. A stimulus is a reinforcer if a behavior increases in frequency as a result of being followed by that stimulus, whether the stimulus followed the behavior quickly or not. But if the stimulus DOES follow the behavior quickly (preferably within 1 second, but at most within 60 seconds), then it DIRECTLY reinforces that particular behavior. If the stimulus follows the behavior by more than 60 seconds, and yet the frequency of the behavior still increases, then that stimulus is still a reinforcer, according to the definition. But it doesn’t DIRECTLY reinforce that particular behavior. Instead it INDIRECTLY reinforces the behavior. We’ll learn more about direct and indirect reinforcement in later chapters (like in Ch. 22).

This leads us to another very important principle, which is that behaviors increase in frequency ONLY when they’re quickly followed by delivery of a reinforcer. So if that’s true, you’re thinking, then how come a behavior that’s followed by a reinforcer more than 60 seconds later (maybe even as much as 15 minutes, a day, 2 months, ...) will still increase in frequency? It’s because in between that behavior and the delivery of that reinforcer, there must have been some other stimulus that quickly and directly reinforced the behavior. That’s the answer to the mystery. But it presents us with another mystery, which is “What is that other stimulus that quickly and directly reinforces the behavior?” Stay tuned.