To recap, Thorndike had observed the learning that took place when a cat tried to escape one of his “puzzle boxes.” According to Thorndike, the cats learned to escape by repeating actions that produced desirable outcomes and by eliminating behaviors that produced what he called “annoying” outcomes, or outcomes featuring either no useful effects or negative effects (1913, p. 50). Consequently, the law of effect states that a behavior will be “stamped into” an organism’s repertoire depending on the consequences of the behavior (Thorndike, 1913, p. 129).
The association between a behavior and its consequences is called operant or instrumental conditioning. In this type of learning, organisms operate on their environment, and their behavior is often instrumental in producing an outcome. B. F. Skinner extended Thorndike’s findings using an apparatus that bears his name—the Skinner box, a modified cage containing levers or buttons that can be pressed or pecked by animals (see Figure 8.7).
The Skinner Box.
A specially adapted cage called a Skinner box, after behaviorist B. F. Skinner, allows researchers to investigate the results of reinforcement and punishment on the likelihood that the rat will press the bar.
Operant conditioning differs from classical conditioning along several dimensions. By definition, classical conditioning is based on an association between two stimuli, whereas operant conditioning occurs when a behavior is associated with its consequences. Classical conditioning generally works best with relatively involuntary behaviors, such as fear or salivation, whereas operant conditioning involves voluntary behaviors, like walking to class or waving to a friend.
8-4aTypes of Consequences
As we all know from experience, some types of consequences increase behaviors, while others decrease behaviors. Skinner divided consequences into four classes: positive reinforcement, negative reinforcement, positive punishment, and negative punishment. Both types of reinforcement increase their associated behaviors, whereas both types of punishment decrease associated behaviors (see Table 8.2).
Types of Consequences
Add stimulus to environment
Remove stimulus from environment
We all have unique sets of effective reinforcers and punishers. You might think that getting an A in a course is reinforcing, making all those extra hours spent studying worthwhile, but top grades may be less meaningful to the student sitting next to you, who came to college for the social life. A parent might spank a child, believing that spanking is an effective form of punishment, only to find that the child’s unwanted behavior is becoming more rather than less frequent. For some children, the reward of getting the parent’s attention overrides the discomfort of the spanking part of the interaction. In other words, the identity of a reinforcer or punisher is defined by its effects on behavior, not by some intrinsic quality of the consequence. The only accurate way to determine the impact of a consequence is to check your results. If you think you’re reinforcing or punishing a behavior but the frequency of the behavior is not changing in the direction you expect, try something else.
By definition, a positive reinforcement increases the frequency of its associated behavior by providing a desired outcome. Again, each person has a menu of effective reinforcements. In a common application of operant conditioning, children with autism spectrum disorder are taught language, with candy serving as the positive reinforcement. Benjamin Lahey tells of his experience trying to teach a child with autism spectrum disorder to say the syllable “ba” to obtain an M&M candy (Lahey, 1995). After 4 hours without progress, Lahey turned to the child’s mother in frustration, asking her what she thought might be the problem. The mother calmly replied that her son didn’t like M&Ms. Lahey switched to the child’s preferred treat, chopped carrots, and the child quickly began saying “ba.” Chopped carrots are probably not the first reinforcer you would try with a 4-year-old boy, but in this case, they made all the difference