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Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 74 74 PSYCHOLOGY that infant to learn and develop normal intelligence. If the infant had no sense of touch or smell or balance, then learning would be next to impossible. Learning is a more or less permanent change in behavior, or a behavioral tendency, as a result of . Answer: experience. Classical Conditioning: Responding to Signals Imagine that you are reading a menu in a restaurant and your mouth begins to water. Is this an example of classical conditioning? Yes, it is. You were not born with a tendency to salivate when looking at a menu. This is behavior acquired through experience, and, consequently, a kind of learning. Salivating to words on paper is a conditioned reflex. Classical conditioning was the first kind of learning to be studied experimentally. The pioneer researcher into classical conditioning was Ivan Pavlov (1849–1936), a Russian physiologist. Classical conditioning is characterized by the capacity of a previously neutral stimulus to elicit a reflex. If a dog is trained to salivate each time that it hears a tone of a specific frequency, then the tone is the previously neutral stimulus and the act of salivating is the reflex. Pavlov achieved his results primarily with a number of dogs that were trained to patiently cooperate with the researcher while being restrained in harnesses in the laboratory. There are four basic terms, all closely related, that you need to learn as the foundation stones of your understanding of classical conditioning. These are (1) the unconditioned stimulus, (2) the conditioned stimulus, (3) the unconditioned reflex, and (4) the conditioned reflex. The unconditioned stimulus is a stimulus that has an inborn power to elicit a reflex. Food in the mouth is such a stimulus. The physiology of the body is such that when salivary glands are stimulated by food, saliva will flow. (a) Classical conditioning is characterized by the capacity of a elicit a reflex. (b) The unconditioned stimulus is a stimulus that has an reflex. stimulus to power to elicit a Answers: (a) previously neutral; (b) inborn. The conditioned stimulus is created by the learning process. It acquires a power that is sometimes (not always) similar to that of the unconditioned stimulus. If a tone precedes food in the mouth a number of times, then the tone may Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 75 Learning: Understanding Acquired Behavior 75 acquire the power to elicit saliva. If a dog salivates when it hears a tone, then the tone is a conditioned stimulus. It can be argued that the dog has associated the tone with food and that the tone has become a signal conveying the meaning that food is coming soon. Indeed, this is one of the important meanings that Pavlov gave to classical conditioning. He thought of conditioned stimuli as signals. The unconditioned reflex is an inborn response pattern. A dog has an inborn tendency to salivate when food is placed in its mouth. Salivating under these conditions is an unconditioned reflex. The word response is sometimes used in place of the word reflex. This usage, although common, is somewhat imprecise. A response to a stimulus is a behavior pattern that suggests a higher level of organization and complexity than that associated with a reflex. Salivating when reading a menu’s description of a hamburger is a reflex. Ordering the item and asking that the meat be well done is a response. A conditioned reflex is a learned response pattern. If a dog salivates to a tone, then the elicited flow of saliva is a conditioned reflex. (a) What stimulus acquires a power that is sometimes (not always) similar to the unconditioned stimulus? (b) The unconditioned reflex is an response pattern. (c) A response to stimulus is a behavior pattern that suggests a higher level of and than that associated with a reflex. Answers: (a) The conditioned stimulus; (b) inborn; (c) organization; complexity. Several important features of classical conditioning should be noted. First, the word conditioning implies a kind of learning that does not require reflection and reasoning. The learning takes place primarily through a process of association. Infants are capable of classical conditioning. If a baby’s mouth begins to make sucking motions when a milk bottle is in view, then the sucking motions are conditioned reflexes. Second, as indicated above, classical conditioning is not limited to dogs and animals. Although Pavlov used dogs as research subjects, the results of his research can be generalized to human beings. Third, conditioned reflexes are involuntary. They are outside of the conscious control of the subject. There are various behavioral patterns associated with classical conditioning. Three of these are extinction, stimulus generalization, and discrimination. Extinction takes place when the conditioned stimulus is presented a number of times without the unconditioned stimulus. If a conditioned dog is presented with a tone, it will salivate. However, if the tone is presented without food a sufficient number of times, the tone will cease to elicit the conditioned reflex. The dog has, Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 76 76 PSYCHOLOGY in effect, unlearned the conditioned reflex. Extinction should not be confused with forgetting. Extinction is an active process that is designed to eliminate a conditioned reflex. The process of actively extinguishing a conditioned reflex is taken advantage of in desensitization therapy (see chapter 15). (a) The word conditioning implies a kind of learning that does not require and . (b) Outside of the conscious control of the subject, conditioned reflexes are said to be . (c) What phenomenon appears when the conditioned stimulus is presented a number of times without the unconditioned stimulus? Answers: (a) reflection; reasoning; (b) involuntary; (c) Extinction. Stimulus generalization occurs when a stimulus that is similar to an original conditioned stimulus elicits a conditioned reflex. For example, let’s say that a dog is trained to salivate to a pitch that is the equivalent of middle C on the piano. If a pitch the equivalent of D, a note that is close to C, is sounded, the dog will also salivate. As the pitch goes higher, there may be some salivation. If the pitch gets high enough, salivation will stop. This is discrimination, the subject’s ability to tell the difference between an original conditioned stimulus and other stimuli. In a classical experiment, Rosalie Raynor, an assistant to John B. Watson, trained a child to be afraid of a white rat. In subsequent testing, the child, known in the research literature as Little Albert, showed fear reactions (conditioned reflexes) when he saw a different white rat, a Santa Claus mask (with white fur), or a rolled-up white terrycloth dishtowel. This research provides an example of stimulus generalization in a human being. (a) What phenomenon occurs when a stimulus that is similar to an original conditioned stimulus elicits a conditioned reflex? (b) A subject’s ability to tell the difference between an original conditioned stimulus and other stimuli is called . Answers: (a) Stimulus generalization; (b) discrimination. Trial-and-Error Learning: Taking a Rocky Road It is instructive to note that one of the most popular books on writing ever published is called Trial and Error by the novelist Jack Woodford. It sold many copies Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 77 Learning: Understanding Acquired Behavior 77 over a number of years, and communicated to would-be authors that the only way to learn to write was by taking the rocky road of learning by making one’s own mistakes. The first kind of learning to be studied experimentally in the United States was trial-and-error learning. Edward L. Thorndike (1874–1949) first studied maze learning in baby chickens (with the assistance and approval of William James). Later he studied the escape behavior of cats from puzzle boxes. The cats had to learn to pull a string that released a latch connected to a door. The cats learned to pull the string, but only very gradually. They showed no sudden burst of insight or comprehension. Thorndike concluded that the learning was a robotlike process controlled primarily by its outcomes. If a specific behavior helped a cat to escape, that behavior was retained by the cat. Thorndike called this process stamping in, meaning that an action that is useful is impressed upon the nervous system. What stamps in a response, according to Thorndike, is satisfaction. The cat that escapes from a puzzle box is rewarded with food. Thorndike called the tendency to retain what is learned because satisfactory results are obtained the law of effect. Thorndike’s law of effect is the forerunner of what today is usually known as the process of reinforcement (see the next section). (a) If a specific behavior helps a cat to escape from a puzzle box, this behavior is retained by the cat. Thorndike called this process . (b) Thorndike’s law of effect is the forerunner of what today is usually known as the process of . Answers: (a) stamping in; (b) reinforcement. Operant Conditioning: How Behavior Is Shaped by Its Own Consequences Operant behavior is characterized by actions that have consequences. Flick a light switch and the consequence is illumination. Saw on a piece of wood and the consequence is two shorter pieces of wood. Tell a joke and the consequence is (sometimes) the laughter of others. Work hard at a job all week and the consequence is a paycheck. In each of these cases the specified action “operates” on the environment, changes it in some way. It was B. F. Skinner (1904–1990) who applied the term operant to the kind of behaviors described above. He saw that operant behavior is both acquired and shaped by experience. Consequently, he identified it as a kind of learning. In addition, he also categorized it as a form of conditioning because he believed that such concepts as consciousness and thinking are not necessary to explain much (perhaps most) operant behavior. Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 78 78 PSYCHOLOGY Skinner, long associated with Harvard, invented a device called the operant conditioning apparatus; its informal name is the Skinner box. Think of the apparatus as something like a candy machine for animals such as rats and pigeons. A rat, for example, learns that it can obtain a pellet of food when it presses a lever. If the pellet appears each time the lever is pressed, the rate of lever pressing will increase. Lever pressing is operant behavior (or simply an operant.) The pellet is a reinforcer. A reinforcer is a stimulus that has the effect of increasing the frequency of a given category of behavior (in this case, lever pressing). (a) Operant behavior is characterized by actions that have (b) The formal term for a Skinner box is the . . Answers: (a) consequences; (b) operant conditioning apparatus. The concept of reinforcement plays a big part in Skinner’s way of looking at behavior. Consequently, it is important to expand on the concept. Note in the above definition that a reinforcer is understood in terms of its actual effects. It is to be distinguished from a reward. A reward is perceived as valuable to the individual giving the reward, but it may not be valued by the receiving organism. In the case of a reinforcer, it is a reinforcer only if it has some sort of payoff value to the receiving organism. By definition, a reinforcer has an impact on operant behavior. Its function is always to increase the frequency of a class of operant behaviors. One important way to categorize reinforcers is to refer to them as positive and negative. A positive reinforcer has value for the organism. Food when you are hungry, water when you are thirsty, and money when you’re strapped for cash all provide examples of positive reinforcers. (a) The function of a reinforcer is always to ant behaviors. (b) A the frequency of a class of oper- has value for the organism. Answers: (a) increase; (b) positive reinforcer. A negative reinforcer has no value for the organism. It does injury or is noxious in some way. A hot room, an offensive person, and a dangerous situation all provide examples of negative reinforcers. The organism tends to either escape from or avoid such reinforcers. The operant behavior takes the subject away from the reinforcer. Turning on the air conditioner when a room is hot provides an example of operant behavior designed to escape from a negative reinforcer. Note that the effect of the negative reinforcer on behavior is still to increase the frequency of a class of operants. You are more likely to turn on an air conditioner tomorrow if you have obtained relief by doing so today. Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 79 Learning: Understanding Acquired Behavior 79 It is also important to note that a negative reinforcer is not punishment. In the case of punishment, an operant is followed by an adverse stimulus. For example, a child sasses a parent and then gets slapped. Getting slapped comes after the child’s behavior. In the case of a negative reinforcer, the adverse stimulus is first in time. Then the operant behavior of escape or avoidance follows. (a) Operant behavior takes a subject from a negative reinforcer. (b) In the case of punishment, an operant is by an adverse stimulus. Answers: (a) away; (b) followed. Another important way to classify reinforcers is to designate them as having either a primary or a secondary quality. A primary reinforcer has intrinsic value for the organism. No learning is required for the worth of the reinforcer to exist. Food when you are hungry and water when you are thirsty are not only positive reinforcers, as indicated above, they are also primary reinforcers. A secondary reinforcer has acquired value for the organism. Learning is required. Money when you’re strapped for cash is a positive reinforcer, as indicated above, but it is a secondary one. You have to learn that cash has value. An infant does not value cash, but does value milk. A medal, a diploma, and a trophy all provide examples of secondary reinforcers. (a) A has intrinsic value for an organism. (b) A has acquired value for an organism. Answers: (a) primary reinforcer; (b) secondary reinforcer. One of the important phenomena associated with operant conditioning is extinction. Earlier, we discussed how extinction takes place when the conditioned stimulus is presented a number of times without the unconditioned stimulus. Extinction also takes place when the frequency of a category of operant responses declines. If, using the operant conditioning apparatus, reinforcement is withheld from a rat, then lever pressing for food will decline and eventually diminish to nearly zero. The organism has learned to give up a given operant because it no longer brings the reinforcer. Both animal and human research on extinction suggest that it is a better way to “break” bad habits than is punishment. If a way can be found to eliminate the reinforcer (or reinforcers) linked to a behavior pattern, the behavior is likely to be given up. Punishment tends to temporarily suppress the appearance of an operant, but extinction has not necessarily taken place. Consequently, the unwanted operant has “gone underground,” and may in time surface as an unpleasant surprise. Also, punishment is frustrating to organisms and tends to make them more aggressive. Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 80 80 PSYCHOLOGY (a) Extinction takes place when the frequency of a category of operant responses . (b) Punishment is frustrating to organisms and tends to make them more . Answers: (a) declines; (b) aggressive. Another important phenomenon associated with operant conditioning is the partial reinforcement effect, the tendency of operant behavior acquired under conditions of partial reinforcement to possess greater resistance to extinction than behavior acquired under conditions of continuous reinforcement. Let’s say that rat 1 is reinforced every time it presses a lever; this rat is receiving continuous reinforcement. Rat 2 is reinforced every other time it presses a lever; this rat is receiving partial reinforcement. Both rats will eventually acquire the lever-pressing response. Now assume that reinforcement is withheld for both rats. The rat that will, in most cases, display greater resistance to extinction is rat 2. Skinner was surprised by this result. If reinforcement is a kind of strengthening of a habit, then rat 1, receiving more reinforcement, should have the more well-established habit. And it should demonstrate greater resistance to extinction than rat 2. Nonetheless, the partial reinforcement effect is a reality, and Skinner became interested in it. He and his coworkers used many schedules of reinforcement to study the partial reinforcement effect. In general, it holds for both animals and human beings that there is indeed a partial reinforcement effect. Random reinforcement is determined by chance, and is, consequently, unpredictable. If behavior is acquired with random reinforcement, it exaggerates the partial reinforcement effect. Skinner was fond of pointing out that random payoffs are associated with gambling. This explains to some extent why a well-established gambling habit is hard to break. (a) Operant behavior acquired under conditions of partial reinforcment tends to possess greater resistance to than behavior acquired under conditions of continuous reinforcement. (b) What kind of reinforcement is determined by chance? Answers: (a) extinction; (b) Random reinforcement. Assume that an instrumental conditioning apparatus contains a light bulb. When the light is on, pressing the lever pays off. When the light is off, pressing the lever fails to bring forth a reinforcer. Under these conditions, a trained experimental animal will tend to display a high rate of lever pressing when the light is on and ignore the lever when the light is off. The light is called a discriminative stimulus, meaning a stimulus that allows the organism to tell the difference between a situation that is potentially reinforcing and one that is not. Cues used to train animals, such as whistles and hand signals, are discriminative stimuli. Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 81 Learning: Understanding Acquired Behavior 81 Skinner notes that discriminative stimuli control human behavior, too. A factory whistle communicating to workers that it’s time for lunch, a bell’s ring for a prizefighter, a school bell’s ring for a child, and a traffic light for a driver are all discriminative stimuli. Stimuli can be more subtle than these examples. A lover’s facial expression or tone of voice may communicate a readiness or lack of readiness to respond to amorous advances. Skinner asserts that in real life both discriminative stimuli and reinforcers automatically control much of our behavior. A stimulus that allows the organism to tell the difference between a situation that is potentially reinforcing and one that is not is called a . Answer: discriminative stimulus. Consciousness and Learning: What It Means to Have an Insight Although classical and operant conditioning play a large part in both animal and human learning, it is generally recognized by behavioral scientists that these two related processes give an insufficient account of the learning process, particularly in human beings. Consequently, it is important to identify at least four additional aspects of learning. These are (1) observational learning, (2) latent learning, (3) insight learning, and (4) learning to learn. Observational learning takes place when an individual acquires behavior by watching the behavior of a second individual. Albert Bandura, a principal researcher associated with observational learning, identified important features of this particular process. The second individual is a model, and either intentionally or unintentionally demonstrates behavior. If the observer identifies with the model and gains imaginary satisfaction from the model’s behavior, then this is vicarious reinforcement. Vicarious reinforcement is characterized by imagined gratification. Psychologically, it acts as a substitute for the real thing. Let’s say that Jonathan admires a particular tennis star. When the star wins an important tournament, Jonathan is ecstatic. This emotional state is a vicarious reinforcer. It should be noted that the concept of watching a model is very general. Reading a mystery novel and identifying with the detective is a kind of observational behavior. The thrills associated with the hero’s adventures are vicarious thrills. (a) What kind of learning takes place when an individual acquires behavior by watching the behavior of a second individual? (b) A either intentionally or unintentionally demonstrates behavior. Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 82 82 PSYCHOLOGY (c) is characterized by imagined gratification. Answers: (a) Observational learning; (b) model; (c) Vicarious reinforcement. Social learning theory, associated with Bandura’s research, states that much of our behavior in reference to other people is acquired through observational learning. Let’s say that Carol is a fifteen-year-old high school student. She is on the fringe of a group of adolescent females who admire a charismatic eighteenyear-old named Dominique. Dominique smokes, uses obscenities, and brags about her sexual exploits. Carol observes Dominique and obtains a lot of vicarious reinforcement from Dominique’s behavior. If Carol begins to imitate Dominique’s behavior, then social learning has taken place. Both prosocial behavior and antisocial behavior can be acquired through observational learning. Prosocial behavior is behavior that contributes to the long-run goals of a traditional reference group such as the family or the population of the nation (see chapter 16). If an individual admires one or both parents, then the parents may be taken as role models. Many adolescents and young adults acquire attitudes and personal habits that resemble those of their parents. If one is patriotic and ready to defend one’s nation during time of war, it is quite likely that the individual is taking important historical figures such as presidents and generals as role models. Antisocial behavior is behavior that has an adverse impact on the long-run goals of a traditional reference group. From the point of view of Carol’s parents, if Carol begins to act like Dominique, then Carol’s behavior is antisocial. (a) What theory states that much of our behavior in reference to other people is acquired through observational learning? (b) is behavior that contributes to the long-run goals of a traditional reference group. (c) is behavior that has an adverse impact on the long-run goals of a traditional reference group. Answers: (a) Social learning theory; (b) Prosocial behavior; (c) Antisocial behavior. Latent learning is a second kind of learning in which consciousness appears to play a large role. Pioneer research on latent learning is associated with experiments conducted by the University of California psychologist Edward C. Tolman and his associates. Let’s say that a rat is allowed to explore a maze without reinforcement. It seems to wander through the maze without any particular pattern of behavior. It is probably responding to its own curiosity drive, but no particular learning appears to be taking place. Let’s say that after ten such opportunities, reinforcement in the form of food in a goal box is introduced. The rat, Brun_0471443956_4p_06_r1.qxd 6/27/02 1:45 PM Page 83 Learning: Understanding Acquired Behavior 83 if it is typical, will quickly learn to run the maze with very few errors. Its learning curve is highly accelerated compared to that of a rat that has not had an earlier opportunity to explore the maze. This is because the first rat was actually learning while it was exploring. The function of reinforcement in this case is to act as an incentive, a stimulus that elicits and brings forth whatever learning the organism has acquired. Note that the learning was actually acquired when the rat was exploring. Therefore learning was taking place without reinforcement. Such learning is called latent learning, meaning learning that is dormant and waiting to be activated. Let’s say that Keith is an adolescent male. For years his mother has forced him, with no particular reinforcement, to make his bed and hang up his clothes neatly. But Keith has, from his mother’s point of view, been a slow learner. He does both tasks poorly. He enlists in the army shortly after his eighteenth birthday. In basic training he makes his bed and hangs up his clothes neatly. He has been told that he will obtain his first weekend pass only if he performs various tasks properly. The fact that Keith shows a very rapid learning curve under these conditions provides an example of latent learning. He was learning under his mother’s influence, but he wasn’t motivated to bring the learning forth. The process of latent learning calls attention to the learning-performance distinction. Learning is an underlying process. In the case of latent learning it is temporarily hidden. Performance is the way in which learning is displayed in action. Only performance can actually be observed and directly measured. (a) is learning that is dormant and waiting to be activated. (b) is the way in which learning is displayed in action. Answers: (a) Latent learning; (b) Performance. Insight learning is a third kind of learning in which consciousness appears to play a major role. Groundbreaking research on insight learning was conducted by Wolfgang Köhler, one of the principal Gestalt psychologists. One of Köhler’s principal subjects was an ape named Sultan. Sultan was presented with two short handles that could be assembled to make one long tool, a kind of rake. An orange was placed outside of Sultan’s cage and it was beyond the reach of either handle. Sultan spent quite a bit of time using the handles in useless ways. He seemed to be making no progress on the problem. Then one day Sultan seemed to have a burst of understanding. He clicked together the handles and raked in the orange. Köhler called this burst of understanding an insight, and defined it as a sudden reorganization of a perceptual field. Originally, Sultan’s perceptual field contained two useless handles. With insight, Sultan’s perceptual field contained a long rake. The conscious mental process that brings a subject to an insight is called insight learning.