Practice to Inhibit a Behavior
Inhibition by the Frontal Lobes
You have an auditory short-term store that can probably retain about seven digits. In other words, if someone says six or seven digits to you, even quickly, you can probably repeat them back correctly. This auditory short-term store seems to be completely perceptual. However, if you want to say a particular word, the act of saying that word uses your auditory short-term store, even if you do not say the word out loud but instead just mouth it. Similarly, if you have to write a digit, that uses the visual short-term store normally used to remember what you have seen (Frick, 1985).
The theory, probably correct, is that you must have an image of what you want to accomplish before you can accomplish it.
The question is, what if you want to inhibit an action. Do you also need a image of what you are trying to inhibit? The auditory and visual short-term stores are in the back part of the brain; the front of the brain is well-accepted to be involved in inhibiting behavior.
One theory of why practicing a tic or stutter can eliminate the stutter is simply that it gives the frontal lobes the information it needs to inhibit the behavior.
Suppose you are having trouble going to sleep, and you think you are bothered by some noise, such as a water faucet dripping. People can go to sleep in the middle of a war, and people living in Manhatten regularly fall asleep. So it is unlikely that the noise was the problem. But you think it is the problem.
Then it does become a problem. You will try to ignore the noise. You think that's a good strategy. But it won't work. Counter-intuitively, your best strategy is probably to pay attention to the noise. As Dr. Levine notes, all research suggests that it is impossible to pay attention to a repetitive boring stimulus for any length of time.
This perhaps has the same explanation as for tics and stuttering. Someplace in the brain inhibits attention to unimportant noises. Perhaps this part of the brain needs a good representation of that noise.
One line of psychological research is asking subjects to not to think a particular thought. This of course tends to be ineffective. Of course, if I ask you not to think about a white polar bear, you are more likely to think about a white polar bear than if I did not ask you. Research often finds that if I ask you not to think about something, that in a way you are more likely to think about it than if you are allowed to think about it. There is a discussion of this here
The practical point is that the person with tics might try not to think about the tic, making things worse; the person who stutters is likely to try not to think about stuttering, making things worse. There is also a general point that when it comes to controlling thoughts, intention does not always work.
The primary experimental investigation of the use of practice to inhibit a behavior is on bruxism
, which is grinding your teeth at night. It doesn't seem to work. Ironically, there is research showing that people cannot, when they are awake, properly imitate the actual movements they use when they gring their teeth at night. Also, it is not clear that the parts of the brain needed to inhibit the teeth-grinding are functional during sleep.
Therefore, the failure of practice to inhibit bruxism does not seem to call into question its use in inhibiting tics or stuttering.
According to the theories of our culture, when you practice your golf swing, you are supposed to practice the correct swing and only the correct swing
. You would never practice slicing the ball, for example. However, the underlying assumption is that your golf swing is a habit, not a skill. This assumption is probably wrong. And as a skill, it doesn't hurt you to practice your slice, and it might (and in fact probably will) improve your skill to practice that.
This probably had nothing to do with inhibiting stuttering and tics. But it illustrates a more general point, that the theories of our culture are not correct.
The technical term is "negative practice". While the outcome is positive, it is in the opposite direction from the usual effect of practice. Fred's innovation is "contingent negative pracice", because it occurs after the behavior occurs.
Contingent negative practice has been used to completely eliminate pica, which is the ingestion of inedible objects (ref.). Negative practice was used to reduce shouting in a severely brain-injured patient (ref.).
The use of negative practice has been used in clinical therapy to treate a variety of problems. See this website for a discussion. Dr. Levine has successfully used this approach to treat a variety of problems.
In a 1932 book, Knight Dunlap discussed the role of negative practice in treating stuttering. It is not clear from this reference
. How effective it was. There are two very useful points to take from his discussion.
First, Dunlap stresses the importance of the stuttering that is practice being like the stuttering that that patient actually does. He claims that it is very difficult to teach the stutterer to stutter voluntarily in the same way that he/she stutters involuntarily. This points to the strong advantage of using contingent negative practice. When the practice follows the stuttering and imitates it, that maximizes the chance that the practice will be the same as the involuntary stuttering. Dunlap apparently did not use contingent negative practice.
Second, Dunlap stresses that the behavior the subject is practicing is not the same as the involuntary stuttering. First, it is a voluntary behavior. For Dunlap, the goal is to make an involuntary behavior voluntary, so that it can be controlled. Second, Dunlap says the "affective and ideational" components are different. "Affect" means that the stutterers emotional state is different. The involuntary stuttering is associated with anxiety, which probably increases the stuttering; the voluntary action is not supposed to be associated with anxiety. I think "ideational" refers to the sensory image producing the behavior, as discussed at the start of this essay.