It also contains a device to record the animal’s responses (Figure 8.5). A Skinner box (operant chamber) is a structure that is big enough to fit a rodent or bird and that contains a bar or key that the organism can press or peck to release food or water. Skinner created specially designed environments known as operant chambers (usually called Skinner boxes) to systematically study learning. Skinner (1904-1990) expanded on Thorndike’s ideas to develop a more complete set of principles to explain operant conditioning. The influential behavioural psychologist B. Thorndike described the learning that follows reinforcement in terms of the law of effect. When Thorndike placed his cats in a puzzle box, he found that they learned to engage in the important escape behaviour faster after each trial. Unsuccessful responses, which produce unpleasant experiences, are “stamped out” and subsequently occur less frequently. Observing these changes in the cats’ behaviour led Thorndike to develop his law of effect, the principle that responses that create a typically pleasant outcome in a particular situation are more likely to occur again in a similar situation, whereas responses that produce a typically unpleasant outcome are less likely to occur again in the situation (Thorndike, 1911). The essence of the law of effect is that successful responses, because they are pleasurable, are “stamped in” by experience and thus occur more frequently. The next time the cat was constrained within the box, it attempted fewer of the ineffective responses before carrying out the successful escape, and after several trials the cat learned to almost immediately make the correct response. But eventually, and accidentally, they pressed the lever that opened the door and exited to their prize, a scrap of fish. At first the cats scratched, bit, and swatted haphazardly, without any idea of how to get out. In his research Thorndike (1898) observed cats who had been placed in a “puzzle box” from which they tried to escape (“Video Clip: Thorndike’s Puzzle Box”). Thorndike (1874-1949) was the first scientist to systematically study operant conditioning. How Reinforcement and Punishment Influence Behaviour: The Research of Thorndike and Skinner In operant conditioning the organism learns from the consequences of its own actions. Operant conditioning occurs when a dog rolls over on command because it has been praised for doing so in the past, when a schoolroom bully threatens his classmates because doing so allows him to get his way, and when a child gets good grades because her parents threaten to punish her if she doesn’t. Operant conditioning, on the other hand, is learning that occurs based on the consequences of behaviour and can involve the learning of new actions. The organism does not learn something new but rather begins to perform an existing behaviour in the presence of a new signal. In classical conditioning the organism learns to associate new stimuli with natural biological responses such as salivation or fear.
0 Comments
Leave a Reply. |