A lot of families call me to help them when intermittent reinforcement methods are not working. This study may shed light on the situation.
One of the useful principles discovered by behavioral psychologists is that intermittent reinforcement increases resistance to extinction. The word intermittent means not every time. Intermittent reinforcement contrasts with continuous reinforcement. Under conditions of continuous reinforcement, the organism is reinforced every time it makes the required response.
What effects do continuous and intermittent reinforcement have upon speed of extinction? Why?
For example, under continuous reinforcement, every time the rat hits the bar, it receives a food pellet. Under intermittent reinforcement, the rat might be required to hit the bar 50 times to get the pellet, or the rat might be reinforced only once every five minutes, or the rat might be reinforced only when you are in the room, or in accordance with some other pattern, but not every time. Any pattern of reinforcement other than continuous reinforcement is a form of intermittent reinforcement.
Extinction, as you recall, is a process of eliminating a behavior by stopping the delivery of reinforcers responsible for maintaining the behavior. Intermittent reinforcement makes extinction slower or harder to accomplish. The reason is that intermittent reinforcement makes an extinction period harder for animals to discriminate.
During an extinction period, a behavior is never reinforced. If the response has been continually reinforced in the past, the animal will quickly notice this; it will discriminate the extinction period. It will stop responding soon. By contrast, if a response is intermittently reinforced, then the animal grows accustomed to periods of no reinforcement. If an experimenter tries to extinguish the behavior by cutting off all reinforcement, the animal is less likely to notice that extinction is taking place, or more likely to persist with the behavior in the expectation that reinforcement may resume again as it has in the past. The result is that animals with a history of intermittent reinforcement do not stop a behavior as quickly as animals with a history of continuous reinforcement. Instead, they show resistance to extinction.
How might this knowledge be important for parents?
The fact that intermittent reinforcement produces persistence or resistance to extinction is an important insight for parents. Parents try to discourage a child from throwing tantrums, but some parents tire under the onslaught of the child’s rage and “cave in” by reinforcing the child. In effect, they are putting the child on an intermittent reinforcement schedule. This makes the tantrums harder to stop in the future. The child will show resistance to extinction, having learned in the past that persistence pays off. Experts on parenting advise parents never to reinforce a tantrum. For example, if a child misbehaves in a store, yelling and screaming in an attempt to get a piece of candy or other desired item, the parent should simply remove the child from the store. To resist the tantrum for a while, then break down and reinforce the child, makes the behavior more persistent in the future.
Extinction-Induced Resurgence (the “extinction burst”)
During an extinction period, animals usually show a great variety of behaviors. The animal appears to test variations of behavior to see if anything will make the reinforcers start again. Epstein (1985) called this “extinction-induced resurgence.” Others call it an extinction burst.
What is extinction-induced resurgence? How is it useful to animal trainers? How was it shown by some dolphins?
Extinction-induced resurgence is a handy phenomenon for animal trainers. If they want animals to learn new tricks, instead of repeating old ones, they put the animals temporarily on an extinction schedule (stop delivering reinforcers). This results in an increase in the activity level and variability of behavior. Then the trainer can pick out a new behavior to be reinforced.
In 1992 two trained porpoises escaped from an enclosure and swam out to sea. A few weeks later they turned up in a waterway next to a golf course, performing tricks for amazed golfers. The porpoises had been trained to perform tricks for fish, but by escaping they put themselves on an extinction schedule (except for catching their own fish). Their behavior at the golf course was lively and variable…and it worked. Before long some golfers bought a load of fresh fish, and the porpoises were feasting.
Porpoises are social animals that often make eye contact before and after a trick. Attention is a powerful reinforcer for most social animals-including humans. Suppose you were on a golf course by the ocean, and you saw a porpoise close to the shore, doing what appeared to be a show trick (such as swimming on its tail, with its head high out of the water) while looking you straight in the eye. Wouldn’t you feel the urge to go buy some fish?
In short, it was not just the porpoises that were being reinforced! This brings to mind the old cartoon in which a rat is sitting in a cage telling another rat, “Boy, have I got that human trained…every time I hit this bar, the human gives me a food pellet.” Humans think they are training the animals, but the animals are just as surely training the humans.