Chapter SummaryClassical Conditioning
Although learning by association had been discussed for centuries, it remained for Ivan Pavlov to capture the phenomenon in his classic experiments on conditioning. Pavlov’s Experiments Pavlov repeatedly presented a neutral stimulus (such as a tone) just before an unconditioned stimulus (UCS, food) that triggered an unconditioned response (UCR, salivation). After several repetitions, the tone alone (now the conditioned stimulus, CS) triggered a conditioned response (CR, salivation). Further experiments on acquisition revealed that classical conditioning was usually greatest when the CS was presented just before the UCS, thus preparing the organism for what was coming. Other experiments explored the phenomena of acquisition, extinction, spontaneous recovery, generalization, and discrimination. Pavlov’s work laid a foundation for John B. Watson’s emerging belief that psychology, to be an objective science, should study only overt behavior, without considering unobservable mental activity. Watson called this position behaviorism. Extending Pavlov’s Understanding The behaviorists’ optimism that learning principles would generalize from one response to another and from one species to another has been tempered. Conditioning principles, we now know, are cognitively influenced and biologically constrained. In classical conditioning, animals learn when to "expect" an unconditioned stimulus. Moreover, animals are biologically predisposed to learn associations between, say, a peculiar taste and a drink that will make them sick, which they will then avoid. They don’t, however, learn to avoid a sickening drink announced by a noise. Pavlov’s Legacy Pavlov taught us that principles of learning apply across species that significant psychological phenomena can be studied objectively, and that conditioning principles have important practical applications. Operant Conditioning Through operant conditioning, organisms learn to produce behaviors that are followed by reinforcing stimuli and to suppress behaviors that are followed by punishing stimuli. Skinner’s Experiments Skinner showed that when placed in an operant chamber, rats or pigeons can be shaped to display successively closer approximations of a desired behavior. Researchers have also studied the effects of primary and secondary reinforcers, and of immediate and delayed reinforcers. Partial reinforcement schedules (fixed-ratio, variable-ratio, fixed-interval, and variable-interval) produce slower acquisition of the target behavior than does continuous reinforcement, but they also create more resistance to extinction. Punishment is most effective when it is strong, immediate, and consistent. However, it can have undesirable side effects. Extending Skinner’s Understanding Skinner’s emphasis on external control of behavior made him both influential and controversial. Many psychologists criticized Skinner (as they did Pavlov) for underestimating the importance of cognitive and biological constraints. For example, research on latent learning and motivation, both intrinsic and extrinsic, further indicates the importance of cognition in learning. Skinner’s Legacy Skinner’s ideas that operant principles should be used to influence people were extremely controversial. Critics felt he ignored personal freedoms and sought to control people. Today, his techniques are applied in schools, sports, workplaces, and homes. Shaping behavior by reinforcing successes is effective. Learning by Observation Another important type of learning, especially among humans, is what Albert Bandura and others call observational learning. In experiments, children tend to imitate what a model both does and says, whether the behavior is social or antisocial. Such experiments have stimulated research on social modeling in the home, within peer groups, and in the media. Children are especially likely to imitate those they perceive to be like them, successful, or admirable. Key TermsLearning - a relatively permanent change in an organism's behavior due to experience.
Associative Learning - learning that certain events occur together. The events may be two stimuli (as in classical conditioning) or a response and its consequences (as in operant conditioning). Behaviorism - the view that psychology (1) should be an objective science that (2) studies behavior without reference to mental processes. Most research psychologists today agree with (1) but not with (2). Classical Conditioning - a type of learning in which an organism comes to associate stimuli. A neutral stimulus that signals an unconditioned stimulus (US) begins to produce a response that anticipates and prepares for the unconditioned stimulus. Also called Pavlovian or respondent conditioning. Unconditioned Response - in classical conditioning, the unlearned, naturally occurring response to the unconditioned stimulus (US), such as salivation when food is in the mouth. Unconditioned Stimulus - in classical conditioning, a stimulus that unconditionally—naturally and automatically—triggers a response. Conditioned Response - in classical conditioning, the learned response to a previously neutral (but now conditioned) stimulus (CS). Conditioned Stimulus - in classical conditioning, an originally irrelevant stimulus that, after association with an unconditioned stimulus, comes to trigger a conditioned response. Acquisition - The initial stage in classical conditioning; the phase associating a neutral stimulus with an unconditioned stimulus so that the neutral stimulus comes to elicit a conditioned response. In operant conditioning, the strengthening of a reinforced response. Extinction - the diminishing of a conditioned response; occurs in classical conditioning when an unconditioned stimulus (US) does not follow a conditioned stimulus (CS); occurs in operant conditioning when a response is no longer reinforced. Spontaneous Recovery - the reappearance, after a pause, of an extinguished conditioned response. Generalization - the tendency, once a response has been conditioned, for stimuli similar to the conditioned stimulus to elicit similar responses. Discrimination - in classical conditioning, the learned ability to distinguish between a conditioned stimulus and stimuli that do not signal an unconditioned stimulus. Operant Conditioning - a type of learning in which behavior is strengthened if followed by a reinforcer or diminished if followed by a punisher. Respondent Behavior - behavior that occurs as an automatic response to some stimulus; Skinner's term for behavior learned through classical conditioning. Operant Behavior - behavior that operates on the environment, producing consequences. Skinner Box - Named for its developer, B.F. Skinner, a box that contains a responding mechanism and a device capable of delivering a consequence to an animal in the box whenever it makes the desired response. Shaping - an operant conditioning procedure in which reinforcers guide behavior toward closer and closer approximations of the desired behavior. Reinforcer - in operant conditioning, any event that strengthens the behavior it follows. Positive Reinforcement - increasing behaviors by presenting positive stimuli, such as food. A positive reinforcer is any stimulus that, when presented after a response, strengthens the response. Primary Reinforcer - an innately reinforcing stimulus, such as one that satisfies a biological need. Conditioned Reinforcer - A stimulus that gains its reinforcing power through its association with a primary reinforcer; also known as secondary reinforcer. Continuous Reinforcement - reinforcing the desired response every time it occurs. Partial Reinforcement - reinforcing a response only part of the time; results in slower acquisition of a response but much greater resistance to extinction than does continuous reinforcement. Fixed-Ratio Schedule - in operant conditioning, a reinforcement schedule that reinforces a response only after a specified number of responses. Variable-Ratio Schedule - in operant conditioning, a schedule of reinforcement that reinforces a response after an unpredictable number of responses. Fixed Interval Schedule - In operant conditioning, a reinforcement schedule that reinforces a response only after a specified time has elapsed. Variable Interval Schedule - in operant conditioning, a schedule of reinforcement that reinforces a response at unpredictable time intervals. Punishment - an event that decreases the behavior that it follows. Cognitive Map - a mental representation of the layout of one's environment. For example, after exploring a maze, rats act as if they have learned a cognitive map of it. Latent Learning - learning that occurs but is not apparent until there is an incentive to demonstrate it. Over-justification Effect - The effect of promising a reward for doing what one already likes to do. Observational Learning - learning by observing others. Modeling - the process of observing and imitating a specific behavior. Prosocial Behavior - positive, constructive, helpful behavior. The opposite of antisocial behavior. Law of Effect - Thorndike's principle that behaviors followed by favorable consequences become more likely, and that behaviors followed by unfavorable consequences become less likely. Intrinsic Motivation - A desire to perform a behavior for its own sake. Extrinsic Motivation - A desire to perform a behavior due to promised rewards or threats of punishment. Mirror Neurons - frontal lobe neurons that fire when performing certain actions or when observing another doing so. The brain's mirroring of another's action may enable imitation, language learning, and empathy. Negative Reinforcement - increasing the strength of a given response by removing or preventing a painful stimulus when the response occurs. |
People To KnowAlbert Bandura: believed that aggression is learned through a process called behavior modeling. He believed that individuals do not actually inherit violent tendencies, but they modeled them after three principles (Bandura, 1976: p.204).
Ivan Pavlov: a Russian scientist most famous for describing the psychological phenomenon referred to as a "conditioned response". B. F. Skinner: believed that the best way to understand behavior is to look at the causes of an action and its consequences. He called this approach operant conditioning. Psych Sim 5 ActivitiesChartsTricky Spots
In classical conditioning, the reinforcement comes BEFORE the actual action and is just an association between two things. In operant conditioning, the reinforcement comes AFTER the action and the action is made in order to get the thing that comes after it.
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