Of course, the next time that Bobby cleans up his room, his parents should provide positive reinforcement only if he cleans it up a little better than before. Now he's got to put the goldfish back in the bowl and pick up all the half-eaten Twinkies before he gets any positive reinforcement. In this way, his parents shape his behavior, modifying it toward the ultimate objective of a sanitary room free of exobiological growth.
Let's suppose Bobby hasn't responded to positive reinforcement. His room is still so dirty that even a seasoned hazardous materials specialist won't go near it. His parents may elect to use punishment as a means of shaping Bobby's recalcitrant behavior. Punishment comes in many forms (spankings, pleasure restrictions, etc.). In Bobby's case, his parents might express their disapproval or use a threat as a means of punishment, thereby shaping his behavior. They may say, "Bobby, we're unhappy with this behavior, and the devil is gonna get you for not cleaning your room." Hopefully, Bobby won't say, "The devil? Get me? Why? I'm doing what he wants."
Of course, at the first sign that Bobby is beginning to clean up his room, his parents would be wise to reduce the punishment or at least begin using positive reinforcement in its place.
The same principles can be applied to students in the cockpit. Suppose you want a student to develop the habit of leveling off within 50 feet of an assigned altitude. Start by requesting a level-off at some altitude. The first time he levels off, regardless of how far off the assigned altitude he is, give him some positive reinforcement. Say, "Billy, that's good. Another 800 feet and you'd have nailed it."
The next time Billy levels off, provide the positive reinforcement only if he's closer than 800 feet to the assigned value. If he missed the mark, you might find it useful to say something like, "Billy, if the airplane isn't at its assigned altitude, it will be very difficult to operate in the traffic pattern, which is a necessary part of learning how to land."
Withholding positive reinforcement or overemphasizing the critical importance of a particular behavior is a form of negative reinforcement. Billy may feel slight anxiety at not receiving an attaboy or at hearing that he may not be able to learn landings until his skill improves. Keep in mind that negative reinforcement isn't punishment; it's the avoidance of punishment. Thus, when Billy performs the proper behavior, the negative feeling (anxiety in this instance) diminishes.
Of course, in extreme situations, a student sometimes doesn't respond to either positive or negative reinforcement. Punishment then becomes an acceptable alternative.
For instance, suppose a student insists on rushing the preflight inspection. As punishment, you might cancel the flight and spend the entire lesson reviewing the perils of hastily examining the airplane. While I'm not a big fan of punishment, it does have its place, especially for students who treat important aviation activities in a cavalier manner.
The secret to behavior modification is to apply the positive or negative reinforcer (or the punishment) immediately after the behavior occurred. Don't wait for three weeks to pass before you say, "By the way, Billy, great job on holding altitude three weeks ago." Positive reinforcement applied too late loses its context and has little value in shaping a student's behavior.
Once the behavior is established, you don't need to constantly reinforce it. For example, if you've reinforced the behavior of rudder coordination, then provide positive reinforcement for that behavior every fourth, fifth, or tenth time that it's performed correctly. This is called a schedule of reinforcement, and it ensures that the desired behavior doesn't diminish with time. You'll have to judge for yourself how often to schedule the reinforcement necessary to maintain the desired behavior.
Finally, remember that reinforcement and punishment are relative. One person may like attaboys, while another may not respond to them. If you know your student, you'll know the type of reinforcer that works best for him.
Whatever you do, don't get too creative with your choice of positive reinforcement. I knew one instructor who gave his students M as a means of reinforcing the desired behavior. Of course, M won't work with less stellar students-they'll spend way too much time trying to peel them.
