Outline LEARNING What is Learning? Theories of Learning Classical conditioning Applying classical conditioning to every day life Operant conditioning Observational, Cognitive, Social learning What is Learning? Learning is the most commonly used word. In common language learning means it is a skill, e.g. learning of linguistic skill, musical skill, reading skill etc. In Psychology, the definition of Learning is much broader. In Psychology, any systematic change of behavior, which is relatively permanent and which occurs as a result of practice or experience is known as learning process. Notice the key points in the above definition. 1. It is a systematic change of behavior. That means any sudden change of behavior cannot be considered learning. For example, an individual who has learned to interact with others suddenly has stopped to interact with others, because his personality has changed after having a head trauma and as a result his personality has changed due to trauma. This change of behavior has occurred not due to any systematic practice or experience. This change in behavior has occurred suddenly due to brain trauma 2. The change of behavior is relatively permanent. If you learned a skill today and not able to remember tomorrow is not learning. For example you learned some musical tune today and you are able to sing that tune for months, which is called learning of a musical tune. If you learn that tune and forget tomorrow is not considered learning. 3. That is why, the role of practice and experience is very important for learning. Change of behavior due to change of physical maturity is not considered learning. Although learning is a permanent change of behavior, it can be unlearned or suppressed. The word learning is utilized in any branch of Psychology A developmental Psychologist uses the learning concept in terms of Language, motor development. The clinical Psychologist utilizes the word to study how previous learning affects present behavior. Social Psychologist utilizes learning concept to study attitudes, prejudice, and social behavior. Theories of learning There are different types of theories which explain the learning process. The textbook emphasizes Behaviorist approach to explain learning as observable changes in behavior. One of the contributions of behaviorist approach is that the principles of learning which apply on animals same principles apply on human behavior. With this approach behaviorists started their experiments on animals and they applied the principles generated in those researches on human beings also. Conditioning: It is a form of learning process in which a connection is acquired between a stimulus and a response. This chapter focuses on 2 types of learning theories. 1. Conditioning Theories 2. Observational learning Theory
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Conditioning Theories What is conditioning? Conditioning is an association or connection between two events or two stimuli. When learning occurs due to connection between two stimuli or events is considered as learning as a result of conditioning. In another words this type of learning is associative learning. According to behaviorists, there are two types of conditioning. 1. Classical conditioning 2. Operant Conditioning Classical conditioning The scientist who formulated this theory was Ivan Pavlov, a Russian Physiologist (1849-1936). He accidentally discovered this theory while conducting experiments on a dog to measure saliva secretion in digestive process. He attached a device to dogs salivary glands to collect saliva and measure the output. The dog started to secret saliva at the sight of food, which is a normal reflex response, an innate, biological process. As the experiment continued, the experimenter discovered that the dog started to salivate to non food objects, e.g. sight of the person who brought the food plate, the sound of the door closing. The normal reflex which was supposed to be connected to food became connected to substitute objects, sight of the person delivering the food or the sound of the door closing. This type of reaction was not normal and Pavlov wanted to know why the response is directed to the substitute stimulus before the response to occur to food. Pavlov concluded that this type of response directed to the substitute stimulus has occurred due to the repeated connection of neutral stimulus occurring with the natural stimulus. Pavlov used the word Conditioning to explain this process. The term conditioning indicates this process of new connection to substitute object. This conditioning process has been acquired by the dog in the process of repeating the experiment. The definition of Classical conditioning Classical conditioning is a type of learning that occurs when a Neutral Stimulus (NS) becomes paired (associated) with the Unconditional stimulus (US) to elicit a Conditional Response (CR). There are 5 basic components in this definition. Unconditional Stimulus (UCS) Unconditional Response (UCR) Neutral Stimulus (NS) Conditional Stimulus (CS) Conditional Response. (CR) The above mentioned components are explained in the Pavlovs experiment, as follows. Before Conditioning: The dog was presented with the food. A bell rang before the food was presented to the dog. This process was repeated several times in the experiment. The dog secretes saliva to Food (UCS) (Normal Reflex, UCR) A sound of bell (NS) appears, before the food presented each time. In the repeated trials of the experiment, the bell (NS) and food (UCS) is paired repeatedly. After the repetition of trials (Conditioning):
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The sound of the bell evokes the saliva secretion even before the food is presented. This is a new connection which dog has learned, which is secretion of saliva to Bell instead of food. The acquisition of this new connection is known as conditioning. After this conditioning process has occurred the bell is referred as Conditioned stimulus (CS) and the secretion of saliva is Conditioned response (CR). In the conditioning process to occur, the timing and the sequence of the pair of Bell and food is important. Following are the steps involved in Classical conditioning which must occur: Acquisition To acquire the connection between UCS (food) and CS (bell), need to be paired together and this needs to be repeated. The connection develops mechanically, without having any awareness that the connection is being developed. For the connection to develop two factors must be there. 1. Contiguity 2. Contingency Contiguity: The NS (the bell) needs to be paired with the UCS (the food) very closely in time, maybe fraction of second. If the bell rings 20 or 30 minutes before the UCS is presented, the connection does not develop or conditioning does not occur. Contingency: The NS (the bell) must occur, before the food (UCS). The bell should be an indicator that the food is coming. Principles of Classical conditioning 1. Stimulus generalization and Discrimination Generalization: The stimulus (CS) which evokes CR, any stimulus similar to the original stimulus (CS) evokes the similar response (CR), is called stimulus generalization. Example: Sound (CS) Crying (CR) High pitch sound Crying response (CR) Low Pitch sound Crying response (CR) Discrimination: When the response occurs only for a specific type of stimulus. Example; when high pitch and low pitch sound was paired, the subject develops connection to only high pitch sound and responds to that and does not develop connection to low pitch sound and does not respond to low pitch sound is an example of Discrimination. Extinction According to Classical Conditioning Theory, conditioning process is relatively permanent as long as UCS (FOOD) and CS (BELL) continue to be present together. Extinction process occurs when UCS is discontinued to be paired with CS. Example: The dog stopped salivating when food was not presented any longer with the bell. So, the extinction process as defined in your textbook is, Gradual weakening of suppression of a previously conditioned response. One important question arises, whether this weakening means that the Conditioned response is unlearned. The answer is conditioned Response is not unlearned. It comes back when the UCS is reintroduced. This time, actually conditioning occurs faster. Spontaneous Recovery: Even if the Extinction occurs, after several hours of extinction process, the conditioned response reappears.
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Pavlov discovered that the dog started to salivate when the bell ring appeared. Classical Conditioning in Humans The development of emotion through classical conditioning in humans can be explained by an experiment conducted by J.B. Watson. Watson conducted an experiment on 11 month old infant, Albert. He would play with a white rat in the lab, and enjoyed playing with the rat. Each time he approached the rat; there will be a loud noise. The infant, Albert, would fearfully cry (UCR) to the sound of the noise (UCS).
Before conditioning: Rat Noise Crying (NS) (UCS) (UCR) After 7 trials conditioning occurred. The infant cried to the sight of the rat. So after conditioning: A new connection developed. That is The rat crying response (CS) (CR) So, little Albert developed fearful emotional reaction to white rat, after conditioning. Albert enjoyed playing with the rat before conditioning. Criticisms of the above experiment 1. The experimenters are obligated to maintain ethical guidelines in any experimental process. This experiment has been criticized on ethical basis. Inducing emotional reaction of fear in a child is unethical. In this fear was induced in an infant. 2. The experiment did not provide an objective measurement of crying behavior. The infants fear was evaluated in subjective terms. Merits of the theory This theory also explains that by changing the relationship of conditioned stimulus and conditioned response the conditioned response can be unlearned or weakened. This process of unlearning is called Counterconditioning. This theoretical finding helped treatment of many irrational fear, phobia. Systematic Desensitization is a method of therapy which is used to provide treatment of Anxiety disorders. The patient is asked to tell the most anxiety provoking aspects of anxiety and the least anxiety related situation. The patient is asked first to learn how to relax by contracting and relax the muscles. Once the patient is able to relax, he is asked to imagine first the least anxious aspect of his problem and is asked to relax. Once he is able to relax reaching a certain point, then gradually he is asked to move upto the next level of anxious aspects of his problem and continues with relaxation in order of hierarchy. This process continues, until the patient is able to relax the highest level of anxiety provoking situation. Therapists have used this technique of Systematic Desensitization successfully to treat phobias, irrational fears of heights or animals. Application of Classical conditioning theory in everyday life. Advertisers, film producers, musicians have borrowed the idea form classical conditioning and have used the technique. For example Advertisers use their Company logo next to the product and add an attractive model. The attractive model is the conditioned stimulus which helps the individual to associate or conditioned to the
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product. Researchers have indicated that many abnormal behaviors, such as irrational fear of height or fear of spider, are all examples of conditioned responses. The therapists using behavior modification techniques focus on weakening of the conditioned responses of irrational fear and help them develop healthy connections of emotional reactions. The classical conditioning technique has been used successfully in medical technique. For example in California, a medical program was conducted in which, to treat alcoholic patients, a medicine emetic was given to the patients. This medicine produced nausea. Right before the patients became nauseated, they were given their favorite alcohol to gargle. In Classical conditioning terms, the smell and taste was the NS. The nausea was UCR, to EMETIC, the UCS. Some patients found this technique to be successful in the treatment of alcohol addiction. Development of prejudice is another example of classical conditioning, which occurs as a result of social learning. (Operant Conditioning is presented in next folder)
OPERANT CONDITIONING Operant conditioning is a second theory of learning, which is different from classical conditioning. There are 2 major differences between these two types of theories. 1. According to Operant conditioning theory an individual learns a behavior (operant), because it brings consequences. A behavior is strengthened because it is reinforced by repeated consequences. A behavior is weakened by punishment and is not repeated. Whereas according to Classical conditioning it is the connection which strengthens the behavior and not the consequences. 2. The behavior learned in Operant conditioning is Voluntary. Why it is so? Because the learned behavior stops appearing if the consequences stop coming. So, the behavior is repeated voluntarily to receive consequences. Just in contrast the behavior in Classical conditioning, involuntary, or passive reflex response. The historical contribution to this theory Edward Thorndike (1874-1949) B. F. Skinner (1904-1990) Thorndikes experiment: He examined the influence of consequences which influenced voluntary behavior. To examine the effect of consequences, Thorndike created a puzzle box and placed a cat inside it. There was a rope connected to the cage. The door of the puzzle box could open, if the rope could be pulled. The cat while roaming around, inside the cage, accidentally pulled the rope, the door opened and the cat could come out of the cage and got food to eat. The cat initially learned to pull the rope through trial and error. Each successful trial to be able to open the door and to get food (consequences), modified cats behavior. Cats behavior became more purposeful (to open the door and receive food), and less random. The cat soon learned to open the door immediately, when placed in the puzzle box. So, the behavior cats became voluntary. Based upon the above mentioned experiment, Thorndike formulated the LAW OF EFFECT. The law of effect states that the probability of an action being repeated is strengthened if it is followed by a
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pleasant, satisfying or positive consequence. the behavior followed by the negative outcomes are weakened In short, rewarded behavior is more likely to reoccur. B. F. Skinners Experiment. B. F. Skinner was a strict behaviorist. He modified Thorndikes theory of Operant conditioning. Since, Skinner was a strict behaviorist; he avoided the concepts; pleasant, satisfying or desirable. According to him, these words or concepts indicate learners internal mental processes which you cannot observe directly or measure them. Skinner argued that instead of considering learners internal world, the focus should be on learners outer world. He considered that learners external world in terms of environmental stimuli and response should be emphasized. The external stimuli and responses can be observed and measured directly. So, Skinner emphasized The Reinforcement, which increases the likelihood of an increase of a behavior, and the Punishment which decreases the likelihood of learned behavior to occur. Skinner also emphasized that Reinforcement and Punishment is effective only if they occur after the behavior has taken place, and not before. That means the reinforcement strengthening a behavior is contingent upon the behavior to occur first. Skinner also emphasized that, the likelihood of a behavior to occur only if the organism desires the behavior and not because the experimenter wants the behavior to occur. So, the behavior learned is a voluntary behavior. Skinners experiment. Skinner conducted his experiments on pigeons or rats, placing them in an apparatus, known as Skinners box. Skinner trained the rat to press lever to receive food pellet. The food pellet was the reinforcement and pressing of the lever was the behavior. Skinner recorded the number of responses the rat needed to learn to press the lever. Principles of Operant Conditioning Skinner was strictly a behaviorist. He explained learning in terms of Strengthening of behavior. He used the key term Reinforcement as instrumental to strengthen behavior. He also explained weakening of responses including positive and negative punishment. Reinforcement as instrumental to strengthening of response. What is reinforcement? Reinforcement is anything that strengthens a response and makes it more likely to reoccur. The reinforcement is classified into 2 categories. 1 Positive Reinforcement 2. Negative Reinforcement Positive Reinforcement: When any stimulus is added or presented, it strengthens the response and likelihood of reoccurring of the response increases. For example: The student puts effort to study (RESPONSE), which brings him good grade (Reinforcement). As the student continues to receive good grades (addition of reinforcement), the student continues to work hard to study. So, the study response is strengthened due to the addition of Positive Reinforcement. Negative Reinforcement: When taking away of a stimulus or removing of a stimulus strengthens the response and the likelihood of reoccurring of the response increases. For example: The individual runs away (Response) form fire (stimulus). Running away from fire allows the individual to avoid painful burns (Negative reinforcement). So, the removal of fire or painful burns is the
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negative reinforcement to strengthen running away behavior. Difference between Negative Reinforcement and Punishment. The meaning of these 2 words apparently seem similar. There is a significant difference between these two words. The positive reinforcement or Negative reinforcement strengthens a Response, Whereas, Punishment weakens a response, and makes it less likely to occur. Example of punishment: A child is misbehaving in the class. The child is punished by standing in front of Principals office. This punishment may weaken the misbehavior in the class. Punishment is used to weaken undesirable behavior. The punishment is most effective when it occurs immediately and consistently. Schedules of Reinforcement This indicates the time interval between Response and delivery of reinforcement. This also indicates the rate or frequency of reinforcement occurring. There are different types of schedules of reinforcement, which lead to different effect on the process of learning. The 2 major types of schedule, based upon time interval are: 1. Continuous Reinforcement 2. Partial reinforcement Continuous Reinforcement The reinforcement is delivered for each correct response. Partial Reinforcement The behavior is reinforces occasionally. Every response is not rewarded The continuous Reinforcement is effective for faster learning but this is not efficient way to strengthen behavior, because in real life each unit of behavior is not reinforced. To maintain a persistent behavior, partial schedule is effective because the person does not know when the reinforcement is going to be delivered, so the person keeps trying. So, once the learning occurs, to maintain the learned behavior, partial reinforcement should be introduced. There are 4 types of Partial Reinforcement. 1. Fixed Ratio. The reinforcement is delivered after a fixed Number of responses. For example, food could be delivered after every 5th correct response. 2. Variable Ratio. There is no fixed ratio. The delivery of reinforcement is unpredictable. Food could be delivered sometimes after 5th correct response, sometimes 7th correct response, and again after 5th response. 3. Fixed Interval. The reinforcement is delivered after a fixed time interval. For example, the food could be delivered after every 15 minutes. 4. Variable Interval. The reinforcement is delivered after a certain time interval, but the time interval is not fixed or predictable. The food could be delivered sometimes in 5 minutes, sometimes in 15 minutes and again in 7 minutes. It is difficult to determine which type of reinforcement is most effective in learning a behavior. The effective influence of types of reinforcement depends upon the type of behavior being learned. Some types of behavior are learned faster with fixed interval; on the other hand, some are more efficiently learned with Variable interval. (Observational Social Learning in next folder) Observational, Cognitive and Social Learning OBSERVATIONAL LEARNING Besides classical and operant conditioning and latent learning process, there is another type of learning process known as Observational learning theory. According to this theory, we learn through OBSERVATION and imitations of others.
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One of the famous experiments to demonstrate this concept came from work of Albert Bandura, 1997) In his experiment, he let one group of children watch televised adults kicking an inflated toy Bobo doll. Later children were allowed to play with same doll in same room Children, who saw live aggressive models, became aggressive with the doll as compared to those children who did not watch the aggressive modeling behavior. According to Bandura 4 separate processes were required for observational learning. 1. Attention: Organisms have to pay attention to learn. 2. Retention: We need to retain what is being paid attention to 3. Motor reproduction: Whatever is learned needs to be reproduced and or repeated. 4. Reinforcement: When we imitate or observe the model, we also want to see whether the model was reinforced. Only then we value the model and observe the model. Application of Social Learning in Everyday Life. We learn about violence, fashion, toys through observing, through TV media. Video Games The research has shown that children become violent playing aggressive games, because they interact with the models, identify with the aggression. Neuroscience and Learning Learning is relatively Permanent change in behavior and mental process, as a result of practice or experience. That means, some type of neurological changes do occur. Every new learning changes the neural connections and synaptic connections. An experiment conducted in 1960 confirmed this belief. Two groups of rats were used. One group of rats was placed in enriched environment, with lots of color and stimulations. Another group of rats were placed in deprived environment, with only food and water but no additional stimulation. After keeping those rats for days, the structure of the brain of the rats changed. The rats raised in enriched environment had more developed Cortex, more branches of dendrites, more developed synapses. Researches have also indicated that human brain also changes according to the environmental influences. So, there is effect of neurological process and the environment in human learning. More enriched the environment; the learning process is more enhanced, because of the neurological changes that occur in the enriched environment. Cognitive factors in Learning Insight So far, we have learned theories of learning, which primarily emphasized Stimulus and Response connection (SR connection). There are other groups of Psychologists who believe this type of connection seems to be very mechanical. They believe that complex learning process is not so mechanical. They believe that, in addition to stimulus response connection, learning is affected by variety of other factors. According to those Psychologists, an individuals thinking, perception also affect learning. S O R theory Stimulus-organism-Response Theory Classic research of Wolfgang Kohler. He used Chimpanzees and Apes to demonstrate the problem solving behavior. He placed banana outside the cage, and left a stick near the cage. The chimpanzee was facing the problem to reach the banana, which is a desirable food for him. To solve this problem, instead of trying different methods through trial and error, the chimpanzee sat down and thought about the situation for a while. Suddenly the chimp would develop sudden insight (a flash of insight). The chimp would jump up, grab the stick and maneuver the banana inside. In another experiment, Kohlers favorite chimp Sultan was placed in a cage. Banana was placed farther away, and 2 sticks were placed inside the cage. The chimp initially lost interest in the bananas and started to play with these sticks. Suddenly the sticks interlocked, and became a bigger stick, which created a
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sudden insight of pulling the banana inside. This sudden flash of insight is known as Aha Experience. Kohler theorized this type of learning as Insight Learning. According to this theory, some mental process occurred in between Banana and retrieving of the banana. Banana (stimulus) Retrieving banana ( Response) (Insight In this above formulation, the insight is the mental process (to understand the problem and come up with the solution), which occurred between stimulus and response. So, according to Insight learning theory, trial and error process is not required to learn. It requires thinking, setting aside previous experiences and assumptions. This thinking leads to sudden insight or understanding of the situation, which leads to that Aha experience and helps solve the problem. Tolmans study of Purposive behavior and LATENT LEARNING Edward C Tolman (18981956), also emphasized Cognitive learning process. He did not believe that Trial and Error and reward is the only factor in learning. He believed that, apparently it looks like the animals in the cages or maze box are demonstrating trial and error response, or random behavior but actually with the help of those random behavior, they are developing a cognitive map in their brain to solve the problem. According to Tolman every behavior is purposeful and goal directed. Following is the experiment which confirmed his viewpoint. He used 3 groups of rats, in a maze box. 1. The first group of rats received no food after aimlessly wandering in the maze to reach the goal. 2. The second group received food immediately after reaching the goal. 3. The third group received the food only after 11th day of success, and not each time they succeeded to reach the goal. The experiment demonstrated that the second groups learning of maze was fastest and the third group was next. However, when the third group started to receive food the performance improved and matched the level of performance which received food on a regular basis. According to Tolman, this proved that the third group was developing the cognitive map of the maze, even if, initially they did not receive the food. The performance accelerated when they started to receive the food, because now they had a reason to learn faster. The reason of acceleration was food reward. The performance accelerated because they already had the cognitive map built when they were roaming in the maze. This type of hidden learning is known as LATENT Learning and indicates a cognitive process. Cultural Influences on Learning If we consider Classical Learning theory, Operant conditioning theory or Cognitive theory it appears that the learning is an universal process. That means that any part of the world or any culture the factors influencing learning process is the same. It does not matter whether we are learning in America or Asia the process of learning is the same. Most Psychologists agree with this assumption. However, the type of learning theory affecting the degree and nature of learning is affected by the cultural influences. For example experimental findings in 2005, indicated that learning of Mexican American students is influenced by observational learning, whereas European American students are influenced by direct instructions. The content of learning is also influenced by culture. For example children growing up in Desert will learn the roots leading to water finding locations or tracking the animals in the desert, whereas children in America do not need to develop animal tracking behavior or finding water well, because there is no need for this and is not practiced in urban towns of America. Children in Bali by age 6 become skilled dancers whereas Norwegian children become skilled skaters at that age.
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