Operant conditioning: principles and applications

¶ … B.F. Skinner is often associated with behavioral psychology, it is Edward Thorndike who set the stage for field. Thorndike's Law of Effect (1901) that successful behaviors tend to be repeated and unsuccessful ones do not set the stage for modern theorists along with the work of Pavlov (1927). Thus we now know that reinforcement always increases the probability that a behavior will occur or be repeated (Skinner, 1953). Positive reinforcement involves providing a stimulus to increase behavior, most often through of the use of a reward like food or praise, whereas negative reinforcement typically involves the removal of an aversive stimulus, such as a noise or pain, to increase the probability that a behavior will occur or be repeated (Skinner, 1953). Negative reinforcement is often confused with punishment but the two techniques perform completely different functions. Whereas reinforcement, positive or negative, always increases the chance that the behavior preceding it will be repeated, punishment always decreases the probability that the behavior preceding its implementation will occur, not increase as in negative reinforcement (Skinner, 1953). Positive punishment, or punishment by application, involves the application of an aversive stimulus to decrease future behaviors from occurring, whereas negative punishment (punishment by removal) involves the removal of some positive stimulus or event with the intent of decreasing the reoccurrence of future behaviors (Skinner, 1953).

Most of us are not behavioral psychologists yet we apply these techniques quite often in our daily routines, especially when dealing with children. For instance, I recently had the pleasure of having to babysit my little five-year-old nephew, Edward (he hates to be called Ed). Edward is quite a mischievous little son of a gun and does not like to sit still. He is a whirlwind of activity. During our time together I needed Edward to sit still and watch the television for about an hour while I ironed some clothes in the other room. Edward was not thrilled about this, and it was very difficult to keep him sitting still. He was running all over the house, knocking things over, making noise, etc. I had a box of mini ice-cream sandwiches in the freezer, so I devised a plan. I put a clock on the top of the television and told Edward that if he would sit still every 10 minutes I would give him an ice cream sandwich. I told him where the hand on the clock would have to be before he could get the first one and he sat there like a little angel. Once the hand reached its position he yelled to me, I brought him a sandwich and he ate it. I showed him where the hand on the clock had to be for the next one and went back to ironing. This worked well for about 40 minutes, which was all the time I needed. One of the problems with reinforcements like this is that they lose their reinforcing value very quickly (after three or four sandwiches Edward was no longer excited about having the next one) but this positive reinforcement exercise to keep Edward in place served its purpose.

My mother is an expert at the use of negative reinforcement, and she knows very little about the difference between reinforcement and punishment. Every Wednesday is trash day at our home, and most people put their trash out on Tuesday evening. My mother is a stickler for getting things done early; my father, well he is much more laid back. If he were to put the trash by the curb just as the garbage man was pulling up in front of our place at 7:00 AM that is fine with him. Not so with my mother. Every Tuesday afternoon it started: "Are you going to get the trash out by morning dear?" she would ask first. "You remember that time in July of 1999 when you forgot to put the trash out and it stank up the garage all week? Boy I hope we don't have to deal with that smell again." Dad would try and watch television and ignore her. Looking out the window Mom would say "Well I see that the Wilsons already have their garbage out, good for them, they don't wait until the last minute." This nagging would continue until finally Dad would get up and put the trash out at the curb. Interestingly he has not missed a trash pickup since July of 1999.

The use of punishment is a bit more controversial than reinforcement, especially with children. Some behaviorists maintain that using punishment to discipline children is not as effective as the use of reinforcement because it is cruel and children can often simply learn to avoid the punishment but still engage in the forbidden behavior. However, punishment can be very effective if it is immediate, inescapable, reasonably intense, and the connection is made between punishment and the behavior one desires to decrease (Millera, Fergusona, & Simpsona, 1998). For example, how many adults will stick the fingers into an electrical wall outlet? If you do that once in your lifetime the chances of you ever intentionally doing it again are slim to none. When I was younger I was fooling around in the basement and broke one of the overhead incandescent light bulbs. Rather than risk being lectured by my father I decided to clean it up myself and replace it (negative reinforcement). When attempting to unscrew the broken bulb I forgot to shut the switch off. SHOCK! That was years ago and I have never forgotten it. You can be darn sure that I make sure that I turn the power off every time I change a bulb now. Thus, the shock eliminated my behavior of sticking my hand in a live circuit, and this is effective positive punishment. When there are dire consequences to a behavior, punishment by application can be very effective and justified, such as spanking or physically restraining a child when he/she attempts to stick his/her finger in a wall outlet, put their hands on a stove top, etc.