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DEPARTMENT OF BEHAVIOURAL SCIENCES B.SC (HUMAN BIOLOGY) TEACHING PROGRAM FOUNDATION OF BEHAVIOURAL SCIENCES COURSE CODE: SMS 154 LEARNING THEORIES • Learning is a field of study in which the behaviorists have traditionally dominated. • The school of behaviorism rose to a large extent as a protest group against what they perceived as excessive emphasis on the unconscious by the Structuralists and the functionalists. LEARNING THEORIES – CONT’D • The behaviorists insisted that psychology study only observable, measurable behaviour, without reference to unobservable mental processes. • Even within their ranks, there are divisions; we have the methodological behaviorists who maintain that psychology should study only the events that they can measure and observe – in other words stimulus and response. • Mental processes to them may well exist, but may not be included in their science; or if they include them, they cautiously inferred from behaviour. LEARNING THEORIES – CONT’D • The radical behaviorists on the contrary do not want to have anything to do with mental processes. B. F Skinner (1990) argued, when you say, “ I intend to…” you really mean “ I am about to…” • That was a good way of saying that any statements alluding to intensions should be converted into a description of behaviour. DEFINING LEARNING LEARNING ? NON PSYCHOLOGICAL • Learning is acquiring new knowledge, behaviors, skills, values, preferences or understanding, – may involve synthesizing different types of information. • The ability to learn is possessed by humans, animals and some machines (artificial intelligence). LEARNING? • Human learning may occur as part of – education, – personal development, or – training. – It may be goal-oriented and may be aided by motivation. • The study of how learning occurs is part of neuropsychology, educational psychology, learning theory, and pedagogy. CONSCIOUS/ UNCONSCIOUS? • Learning may occur consciously or without conscious awareness. HOW EARLY? • There is evidence for human behavioral learning prenatally, in which habituation has been observed as early as 32 weeks into gestation, • That’s an indication that the central nervous system is sufficiently developed and primed for learning and memory to occur very early on in development. TYPES OF LEARNING SIMPLE AND COMPLEX TYPES OF LEARNING • SIMPLE NON – ASSOCIATIVE – Habituation – Sensitization • ASSOCIATIVE – Operant – Classical • IMPRINTING • OBSERVATIONAL / IMITATIONAL/ VICARIOUS/ L/ MODELING COMPLEX TYPES OF LEARNING • More complex forms of learning include higher- level learning involving – – – – – memory Comprehension & language, concepts, and motor skills. and other information - rich mental processes. • In this lecture we shall be concerned with a more basic form of learning (non associative & associative). LEARNING THEORIES – CONT’D • In everyday usage/ everyday sense, learning often refers to formal methods of acquiring new knowledge or skills, such as learning in the classroom or learning to play an instrument. • It is common to think of learning as something that takes place in school, but much of human learning occurs outside the classroom, and people continue to learn throughout their lives. LEARNING THEORIES – CONT’D • Even before they enter school, young children learn to walk, to talk, and to use their hands to manipulate toys, food, and other objects. • They use all of their senses to learn about the sights, sounds, tastes, and smells in their environments. • They learn how to interact with their parents, siblings, friends, and other people important to their world. When they enter school, children learn basic academic subjects such as reading, writing, and mathematics. LEARNING THEORIES – CONT’D • They also continue to learn a great deal outside the classroom. They learn which behaviors are likely to be rewarded and which are likely to be punished. • They learn social skills for interacting with other children. • After they finish school, people must learn to adapt to the many major changes that affect their lives, such as getting married, raising children, and finding and keeping a job.. LEARNING THEORIES – CONT’D • Because learning continues throughout our lives and affects almost everything we do, the study of learning is important in many different fields. • Teachers need to understand the best ways to educate children. Psychologists, Optometrists, social workers, criminologists, Doctors and other humanservice workers need to understand how certain experiences change people’s behaviors. • Employers, politicians, and advertisers make use of the principles of learning to influence the behavior of workers, voters, and consumers. LEARNING THEORIES – CONT’D • what is learning? – Psychological? DEFINING LEARNING • Definition of learning – very difficult. – Subjects with language capabilities could inform the researcher by way of verbal communication – What happens when they cannot communicate? • E.g. in animals, newborns, children (trustworthy) etc. • Only way is to deduce from changes in performance / behaviour. – This is overt, objective – Also unseen/ covert behavior. • FIRST WORD – changes in performance or “changes in behaviour”. • Most importantly; changes in potential behaviour. DEFINING LEARNING • So Psychologists may create various situations conducive to learning and measure a subject’s performance in each. • In each of these the situation should be carefully controlled. Why? – Several factors temporarily affect performance. Examples; • Fatigue* • Emotions and motivation • Health and – These effects are mostly temporal but in learning we need a more permanent change (s) DEFINING LEARNING • Some permanent changes can occur as a result of MATURATION. E.g. walking, lifting certain weight, is it learning? – This does not qualify because it is not a result of prior experience (Capable because of growth). – When you were young, you could not do certain things but when you matured physically, they became easier to do – So some form of EXPERIENCE is necessary DEFINING LEARNING • To distinguish learning from physically based factors, such as maturation or illness, • learning can be designated as a change in performance/ performance potential that result from experience. IMPORTANT WORDS • EXPERIENCE • Relatively permanent • Changes in behaviour/ potential behaviour – E.g Curfew in Tamale – Experiences here @ SMS – acquiring changes in your behaviour/ acquiring potential behavior to be able to treat patients in near future. • Any single, all embracing definition? DEFINITION OF LEARNING • Various definitions. For e g. Coon (1992)*** defines learning as “any relatively permanent change in behavior that can be attributed to experience” p. 189. • Notice that this definition excludes temporary changes caused by motivation, fatigue, maturation, disease/injury, drugs and so forth” • Morris and Maesto (1999) define it as “a process by which experience or practice results in a relatively permanent change in behavior or potential behaviour, p 166. LEARNING DEFINITION – CONT’D • NB: potential behaviour from Morris & Maesto • Hockenbury and Hockenbury (2001) see learning as a process that produces a relatively enduring change in behaviour or knowledge as a result of an individual’s experience, p 163. • Kassin (2001; 174) referred to learning as a relatively permanent change in knowledge or behaviour that comes about as a result of experience. KEYWORDS • • • Relatively Permanent Change Experience and Behaviour/Potential behaviour – It implies that all sorts of events/experience could result in changes in behavior but not all would be regarded as relatively permanent. – Some of these include fatigue, maturation (an automatic biological unfolding of development in an organism as a function of passage of time), drugs or injury HOW OF LEARNING • The definitions say nothing about HOW learning actually takes place. • There are different kinds of learning • How we learn, to a large extent depend in large part on what we are learning. LEARNING THEORIES – CONT’D • Learning is closely related to memory, which is the storage of information in the brain. – Psychologists who study memory are interested in how the brain stores knowledge, where this storage takes place, and how the brain later retrieves knowledge when we need it. • In contrast, psychologists who study learning are more interested in behavior and how behavior changes as a result of a person’s experiences. LEARNING THEORIES – CONT’D • There are many forms of learning, ranging from simple to complex. (More complex forms of learning include learning languages, concepts, and motor skills). • Simple forms of learning involve a single stimulus (e.g.. habituation). – A stimulus is anything perceptible to the senses, such as a sight, sound, smell, touch, or taste. SIMPLE LEARNING NON - ASSOCIATIVE I. II. HABITUATION & SENSITIZATION TYPES OF LEARNING • One of the simplest kind of the learning is acquiring the knowledge that things in the environment exist and differ from one another. • We accomplish this by examining new stimuli with our senses (Curiosity & exploration). • Unfamiliar, intense, or unexpected stimulus tends to produce an ORIENTING REFLEX – A response that involves a whole chain of activities • • • • Looking Listening Touching & Sniffing – Designed to find out what the new stimulus is about. – What happens when we repeatedly encounter the same stimuli? ORIENTING REFLEX •The orienting response disappears The unfamiliar becomes a commonplace •Psychologists say HABITUATION has occurred. (Habituated to that stimulus) HABITUATION • In psychology, habituation is an example of non-associative learning in which there is a progressive diminution of behavioral response probability with repetitive stimulus. • THUS, there’s a tendency to become familiar with a stimulus after repeated exposure to it. • An animal first responds to a stimulus, but if it is neither rewarding nor harmful the animal reduces subsequent responses. • A common example of habituation occurs in the orienting response, in which a person’s attention is captured by a loud or sudden stimulus. HABITUATION • For example, a person who moves to a house on a busy street may initially be distracted (an orienting response) every time a loud vehicle drives by. • After living in the house for some time, however, the person will no longer be distracted by the street noise – • the person becomes habituated to it and the orienting response disappears LEARNING THEORIES – CONT’D • Despite its simplicity, habituation is a very useful type of learning. – Because our environments are full of sights and sounds, we would waste a tremendous amount of time and energy if we paid attention to every stimulus each time we encountered it. – Habituation allows us to ignore repetitive, unimportant stimuli. Habituation occurs in nearly all organisms, from human beings to animals with very simple nervous systems. • Even some one-celled organisms will habituate to a light, sound, or chemical stimulus that is presented repeatedly. HABITUATION - EXPERIMENT • Friedman (1972) demonstrated this by an experiment? – He showed newborn babies a picture of checkerboard patterns. – Each time, the baby looks at it for nearly the full minute it is visible. – This is carried out for six presentations, what happens after this? – Then, on the seventh and eight presentations, the baby looks for only half a minute before turning away. • What happens that the infant now looks for it for half instead of a full minute after the sixth presentation??? HABITUATION - EXPERIMENT – Has the child grown sleepy/ having trouble paying attention? – Has the infant learned the check - board pattern and become bored with it? • That is an example of orienting reflex followed by habituation in the infant's response to the checkerboard pattern. – At 1st the baby was very interested in the picture, but after a while she began to look away. • We behave the same way many times each day, – e.g peculiar rattling noise in your car? • Likely to pay attention. As time goes by, you don’t notice the noise – not because it has stopped. • Why – habituation. What’s the importance?? HABITUATION • When habituation occurs to a stimulus – we must have learned something about it. – In the case of the car noise, we might have learned that this particular sound exists but doesn’t seem to indicate/ constitute any serous problem. • Simple organisms may become habituated. Humans are no exceptions – You buy a newly released CD • After a while u don’t notice it , why? SENSITIZATION • Sensitization, another simple form of learning, is the increase that occurs in an organism’s responsiveness to stimuli following an especially intense or irritating stimulus. – For example, a sea snail that receives a strong electric shock will afterward withdraw its gill more strongly than usual in response to a simple touch. – If your electric iron gives you a shock what happens to your response/ sensitivity to electric irons? – Depending on the intensity and duration of the original stimulus, the period of increased responsiveness can last from several seconds to several days. ASSOCIATIVE LEARNING LEARNING THEORIES ASSOCITIVE L. (CONDITIONING) & SOCIAL LEARNING Consider the following – how do you explain them? • • • Situation I Susie enjoys opening the door whenever the doorbell goes .One evening; she answered the doorbell and at the door was Julie who had dressed up in a costume like a monster. Susie got so terrified that she nearly passed out when she started screaming and run back to lock herself up in her room upstairs. Later she got terrified whenever the doorbell rung. • Scenario II – Kofi is a cancer patient receiving treatment at the KATH Cancer center. – Before each Chemotherapy session, he is given a bowl of ice cream. The chemotherapy makes Kofi Nauseated. Now just seeing the bowl of ice makes him feel nauseated…ANSWER? Consider the following – how do you explain them? • Question!! • Scenario IV • Why do most advertisers use • Subsequently Esther well known peoples such as kicked the machine footballers, actors, singers anytime it delayed in etc. dispensing the drink? – Abedi Pele loves…. Since Gabriel admired – Michael Powell …Guinness Esther so much, he the power. adopted her behaviour to – Bob Santo??? obtain drinks from • Esther & Gabriel scenario delaying vending • In her anger, Esther kicked machines. the machine while Gabriel was still observing. – Explanation?? ANSWER??? LEARNING THEORIES OVERVIEW – LEARNING THEORIES • INTRODUCTION & DEFINITIONS • SIMPLE FORMS OF LEARNING – Habituation – Sensitization • CLASSICAL CONDITIONING… Ivan Pavlov – Pavlov’s experiment – Principles of classical conditioning • • • • Acquisition, Extinction, Generalization & Discrimination – Applications of classical/ Pavlovian principles PIX. OF IVAN PATROVICH PAVLOV OVERVIEW – LEARNING THEORIES • OPERANT CONDITIONING...E. L. Thorndike/ Skinner – Thorndike's experiment & Laws of effect – B.F Skinner’s research – Principles of Operant Conditioning • • • • • • Reinforcement Schedules of Reinforcement Punishment Shaping Extinction Generalization & Discrimination – Applications of operant/ Skinnerian conditioning PIX. OF SKINNER / THORNDIKE OVERVIEW – LEARNING THEORIES • OBSERVATIONAL/ VICARIOUS LEARNING/ MODELING… Albert Bandura – Bandura’s Experiment – Bandura’s theory of Imitation\ – Factor’s affecting imitation – Does TV have influence on behaviour acquisition PIX. OF ALBERT BANDURA LEARNING THEORIES CLASSICAL CONDITIONING DEFINING – key words • CLASSICAL – name Ivan Pavlov gave to the type of learning he heuristically discovered • CONDITIONING – Refers to the fact that the learner is “conditioned”; meaning the learner forms an association, usually between a stimulus and a response or between two stimuli. LEARNING THEORIES – CONT’D • Classical conditioning is a type of learning in which an animal’s natural response to one object or sensory stimulus transfers to another stimulus (formerly neutral). – This illustration shows how a dog can learn to salivate to the sound of a tuning fork, • This was an experiment first carried out in the early 1900s by Russian physiologist Ivan Pavlov. – For conditioning to occur, the pairing of the food with the tuning fork (step 3 in the illustration) must be repeated many times, so that the dog eventually learns to associate the two events. L. THEORIES – Pavlov’s experiment • . CLASSICAL LEARNING • PAVLOV'S VIDEOS\Pavlov's Dogs Get Conditioned3.flv Is this cl.conditioning? • PAVLOV'S VIDEOS\Psych 120 Classical Conditioning.flv CLASSICAL • Ivan Petrovich Pavlov • Russian physiologist Ivan Pavlov discovered a major type of learning, classical conditioning; • Heuristic discovery while conducting experiments on digestion in the early 1900s. He devoted the rest of his life to discovering the underlying principles of classical conditioning L. THEORIES – Pavlov’s experiment L. THEORIES – Pavlov’s experiment • Pavlov was studying how saliva aids the digestive process. – He would give a dog some food and measure the amount of saliva the dog produced while it ate the meal. • After the dog had gone through this procedure a few times, however, it would begin to salivate before receiving any food. – Pavlov reasoned that some new stimulus, such as the experimenter in his white coat, had become associated with the food and produced the response of salivation in the dog. – Pavlov spent the rest of his life studying this basic type of associative learning, which is now called classical conditioning or Pavlovian conditioning. L. THEORIES – Pavlov’s experiment • • Consider the following – how do you explain them? Situation I Susie enjoys opening the door whenever the doorbell goes .One evening; she answered the doorbell and at the door was Julie who had dressed up in a costume like a monster. Susie got so terrified that she nearly passed out when she screaming and running back to lock herself up in her room upstairs. Later she got terrified whenever the doorbell rung. • Scenario II – Kofi is a cancer patient receiving treatment at the KATH Cancer center. Before each Chemotherapy session, he is given a bowl of ice cream. The chemotherapy makes Kofi Nauseated. Now just seeing the bowl of ice makes him feel nauseated. – ANSWER? SOLUTION USING CLASSICAL LEARNING THEORY • PARADIGM II PARADIGM I • Before conditioning – Doorbell No fear in Susie • NS – Monster costume fear • UCS UCR • During Conditioning (Pairing) – Doorbell + Julie’s Monster costume (UCS) Fear in Susie (UCR) • After Conditioning (Pairing) – Doorbell alone fear in Susie • CS CR • Before conditioning – Bowl of ice No Nausea • NS – Chemotherapy Nausea • UCS UCR During Conditioning (Pairing) – Bowl of ice + Chemotherapy (UCS) Makes Kofi nauseated (UCR) After Conditioning (Pairing) – Bowl of ice alone (CS) Makes Kofi feel nauseated (CR) Principles of Classical Conditioning • Following his initial discovery, Pavlov spent more than three decades studying the processes underlying classical conditioning. • He and his associates identified four main processes: – acquisition, – extinction, – generalization, and – discrimination. – CONSTIGUITY (READ PLEASE) AQCUISITION – CONT’D • The acquisition phase is the initial learning of the conditioned response - for example, the dog learning to salivate at the sound of the bell. • Several factors influence the acquisition of CRs. Among them are; – The sequence of CS – UCS presentation, – The intensity of the UCS and – The number of times the CS and UCS are paired AQCUISITION – CONT’D AQCUISITION – CONT’D • SEQUENCE OF CS – UCS PRESENTATION – Influence the strength of the conditioning. – Up to this point we have simply indicated that that the CS should precede the US. (Imprecise). – Rather several sequences for CS – UCS presentation are possible. • Trace conditioning • Delayed conditioning • Simultaneous conditioning • Backward conditioning AQCUISITION – CONT’D • TRACE CONDITIONING • Cs comes on and goes be4 the UCS is presented • Here the UCS is associated with a memory trace of the CS, not with the CS itself. • This produces weaker conditioning, but not as weak as simultaneous or backward conditioning. AQCUISITION – CONT’D • DELAYED CONDITIONING • Comes and stays on, and then the UCS is presented so that they occur together for some time • The presentation of UCS is delayed for a specific interval after the CS has been presented • Researchers found that delayed conditioning for a short interval produces a strong conditioning, whereas longer delays between the CS & UCS produce weak conditioning. • Example, they found 450miliseconds is the optimal interval for conditioning the eyelid closure reflex. (One millisecond = 1/1000 of a second) AQCUISITION – CONT’D • SIMULTANEOUS CONDITIONING • CS comes on exactly the same time as the US. • Example a sound of a metronome and the food powder would be presented to the dog simultaneously • This type results in a weak conditioning. AQCUISITION – CONT’D • BACKWARD CONDITIONING • CS comes on after the UCS. • Example the dog is given food powder and thereafter hear the sound of the metronome • Results in a very weak, if any conditioning at all. AQCUISITION – CONT’D • Conditioning occurs most quickly when the conditioned stimulus (the bell) precedes the unconditioned stimulus (the food) by about half a second. • Conditioning takes longer and the response is weaker when there is a long delay between the presentation of the CS and the UCS • If the conditioned stimulus follows the unconditioned stimulus—for example, if the dog receives the food before the bell is rung — conditioning seldom occurs. AQCUISITION – CONT’D • STRENGTH OF CONDT • The stronger the UCS , the stronger the conditioning – (Holloway & Domjan, 1993) • When Pavlov gave his dogs a small amount of meat powder, they did not salivate as much as he gave them a large amount of meat powder. – Stronger USCs elicit stronger URs; – Weaker UCSs produce weaker URs. • NUMBER OF (CS- UCS) PAIRINGS • The more the CS and the UCS are paired together, the stronger the CR becomes. – If you have eaten at an exceptionally fine restaurant several times, your CRs to the sight of the restaurant and its menu will be stronger than would be if you had eaten there only once. Always True?? *** EXTINTION & SPONTANEOUS RECOVERY • Once learned, a conditioned response is not necessarily permanent. • The term extinction is used to describe the gradual weakening leading to eventual disappearance of the conditioned response by repeatedly presenting the conditioned stimulus (bell) without the unconditioned stimulus (food). • If a dog has learned to salivate at the sound of a bell, an experimenter can gradually extinguish the dog’s response by repeatedly ringing the bell without presenting food afterward. • Does it mean that the dog has forgotten what its learnt? EXTINTION AND S. RECOVERY– cont’d • Extinction does not mean, however, that the dog has simply unlearned or forgotten the association between the bell and the food. – After extinction, if the experimenter lets a few hours pass and then rings the bell again, the dog will usually salivate at the sound of the bell once again. • SPONTANEOUS RECOVERY – The reappearance of an extinguished response after some time has passed is called spontaneous recovery. Graph STIMULUS GENERALIZATION • After an animal has learned a conditioned response to one stimulus, it may also respond to similar stimuli without further training. – If a child is bitten by a large black dog, the child may fear not only that dog, but other large dogs. – If your lecturer slaps you and you see someone who resembles him….? • This phenomenon is called generalization. –* STIMULUS DISCRIMINATION • The opposite of generalization is discrimination, – In this, an individual learns to produce a conditioned response to one stimulus but not to the other stimulus that is similar. – For example, a child may show a fear response to freely roaming dogs, but may show no fear when a dog is on a leash or confined to a pen. » How do we apply these principles to human? ** APPLICATION OF CLASSICAL PRINCIPLES • In an infamous 1921 experiment, John B. Watson and his research assistant Rosalie Rayner conditioned a baby named little Albert (11 month old baby) to fear a small white rat. – How did this happen? – by pairing the sight of the rat with a loud noise. • it showed for the first time that humans can learn to fear seemingly unimportant stimuli when the stimuli are associated with unpleasant experiences. APPLICATION – CONT’D • The experiment also suggested that classical conditioning accounts for some cases of phobias, – Phobia is an irrational or excessive fears of specific objects or situations. • Psychologists now know that classical conditioning explains many emotional responses such as – happiness, – excitement, – anger, and – Anxiety, that people have to specific stimuli. APPLICATION – CONT’D • For example, a child who experiences excitement on a roller coaster may learn to feel excited just at the sight of a roller coaster. • For an adult who finds a letter from a close friend in the mailbox, – the mere sight of the return address on the envelope may elicit feelings of joy and warmth. APPLICATION – CONT’D • Psychologists use classical conditioning procedures to treat phobias and other unwanted behaviors, such as alcoholism and addictions. – In one treatment for alcoholism, patients drink an alcoholic beverage and then ingest a drug that produces nausea. – Eventually they feel nauseous at the sight or smell of alcohol and stops drinking it. – AVERSIVE THERAPY (READ) • To treat phobias of specific objects, • the therapist gradually and repeatedly presents the feared object to the patient while the patient relaxes. • Through extinction, the patient loses his or her fear of the object. • The effectiveness of these therapies varies depending on the individual and on the problem behavior APPLICATION – Contemporary views • Modern research has also shown that conditioning does not always require a close pairing of the two stimuli (…beyond scope) • In taste-aversion learning, people can develop disgust for a specific food if they become sick after eating it, even if the illness begins several hours after eating. • Most associations take repeated experiences to develop. However, one pairing with a strong autonomic arousal can sometimes be enough to develop a conditioned response APPLICATION - SUMMARY • Anxiety disorders benefit greatly from the following classical strategies; – – – – – EXTINCTION, COUNTER CONDITIONING, BIOFEEDBACK, FLOODING & SYSTEMATIC DESENSITIZATION. • EXTINCTION – Extinction happens once the CS ceases to be associated with the US and therefore the conditioned response gets extincted / eliminated. – In Pavlov’s experiment, when the bell no longer signaled food, the dog eventually stopped salivating to the bell. – In the hospital setting, the use of anti- nausea drugs by cancer patients in preparation for hospital attendance will stop the association of hospital with nausea and eventually eliminates the conditioned nausea response. APPLICATION - SUMMARY • COUNTER CONDITIONING – In Counter conditioning, we substitute a negative conditioned response with a positive or nonharmful one. – For example full relaxation is a response, which opposes the arousal of the autonomic nervous system and can be used to eliminate conditioned fear or anxiety responses. Relaxation takes time to learn though • FLOODING – Usually used for treatment of phobias. Here the individual is forcibly exposed to the situation or object they fear until the fear response has completely subsides. We need great caution (Distressing) • BIOFEEDBACK – This involves the use of certain machine which has sensors which pick up autonomic activity such as moisture or temperature change, or muscular tension. – This is fed back as a continuous but variable audible signal (like a metal detector) to the individual. – This feedback can enable the individual to bring what is normally an autonomic reflex under voluntary control. – Thus, the electrical activity of muscle contraction are converted into audible signals – As the individual relaxes, the signal changes. Once completed relaxation is achieved, the signal disappears altogether. APPLICATION - SUMMARY • BIOFEEDBACK – This involves the use of certain machine which has sensors which pick up autonomic activity such as moisture or temperature change, or muscular tension. – This is fed back as a continuous but variable audible signal (like a metal detector) to the individual. – This feedback can enable the individual to bring what is normally an autonomic reflex under voluntary control. – Thus, the electrical activity of muscle contraction are converted into audible signals – As the individual relaxes, the signal changes. Once completed relaxation is achieved, the signal disappears altogether. APPLICATION - SUMMARY • SYSTEMATIC DESENSITIZATION (Wolpe, 1958) • This is a gentler approach to the treatment for anxieties and phobias. • People are first taught relaxation technique to counter their normal autonomic stress response. • They draw up a hierarchy of anxiety provoking events • They then learn to apply the relaxation technique in a hierarchical series of graded situations from imagining a mild fear- producing situation to imagining a more severe fear- producing situation, to looking at pictures or films, to approaching the actual situation, then to actual exposure. • At each stage, the individual must demonstrate control through relaxation before proceeding to the next stage. APPLYING CLASSICAL COND. • It is now known that human could come to fer objects or places because they happened to be associated with aversive experiences – Irrational fears and other anxiety disorders – Recent research also found relationships between classical conditioning and immune system. • All autonomic responses (those involving arousal of ANS) are capable of conditioning by this type of association. – Asthma, which is often caused by the constriction of the bronchus in response to allergen. • If a child has allergic reaction to cat fur, it is possible that the child may eventually only have to see a cat in a distance to develop an asthmatic attack. • Sometimes these types of responses may be generalized to pictures of cats or even other animals APPLYING CLASSICAL COND. • Another example of conditioned reflex response is that of nausea felt by cancer patients during the cause of drug treatment and radiotherapy. – Some eventually experience nausea as they approach the hospital, or even when they just think about it. – In other words, anything associated with the hospital is a conditioned stimulus and nausea becomes a conditioned response. • Finally, the principle of classical conditioning can account for fear of doctors, hospital staff/ medical equipment. – Example, a child who has received a painful injection may later show fer of anyone with white coat or any clinical situation. – The mother and staff may be unaware of the reason for this and feel that the child is behaving irritationally. – Have in taken notice of the fact that as a measure of punishment, parents use injection to check certain undesirable behaviours. APPLYING CLASSICAL COND. • TREATMENT OF ENURESIS – Here bell and pad (like mat) are in use – The bell is attached to the pad and is set to sounds as soon as soon as the first drop of urine touches the mat. – Upon repeated exposures the individual learns to wake up to urinate. LEARNING THEORIES OPERANT CONDITIONING DEFINING OPERANT/ SKINNERIAN/ INSTRUMENTAL CONDITIONING • The type of learning in which behaviors are emitted (in the presence of specific stimuli) to earn reward or avoid punishment • A form of learning in which the consequences of behaviour produce changes in the probability of behavior's occurrence… Why operant? – Operant; describes the organism’s behaviour – behaviour operates on the environment and the environment in turn operate on behaviour. – One essential element in operant conditioning is emitted behaviour and this makes it different from classical conditioning – Thus, unlike classical conditioning in which a response is automatically triggered by some stimulus, (food triggers salivation) response is spontaneous in operant, (voluntarily studying Behavioral Science to gain marks) OPERANT CONDITIONING – cont’d – Voluntary spontaneous actions are called Operant behaviors because they “OPERATE ON THE ENVIRONMENT” – Operant conditioning is usually better than classical at explaining VOLUNTARY behaviour • Unlike classical conditioning, operant conditioning requires action on the part of the learner. • Its not like classical conditioning, in which the conditioned and unconditioned stimuli are presented regardless of what the learner does. • Operant conditioning requires action on the part of the learner. – A boy will not get his snack unless he first cleans up his room. OPERANT CONDITIONING- cont’d • Edward Lee Thorndike was one of the earliest American psychologists to scientifically study animal behaviour. – Pioneer in studying this kind of learning which involved making a certain response because of the consequences it brought. (NAME: Operant/ Instrumental Conditioning). – Around the turn of the century, while Pavlov was busy with his dogs, Thorndike (1898) was using a simple wooden box cage “Puzzle box”*** to study how cats learn. Procedure with hungry cats (next slide for pix) THORDIKES PUZZLE BOX THORNDIKE RESULTS: – Indicated that in the beginning it took the cats quite a while to discover how to open the door. – On each trial it took them less time, until eventually they could escape from the box in almost no time at all. THORDIKES PUZZLE BOX – cont’d • DESCRIPTION – He found that the first time an animal entered the puzzle box, it usually took a long time to make the response required to open the door. – Eventually, however, it would make the appropriate response by accident and receive its reward: escape and food. – As Thorndike placed the same animal in the puzzle box again and again, it would make the correct response more and more quickly. Soon it would take the animal just a few seconds to earn its reward. OPERANT CONDITIONING – cont’d • A second essential element in operant conditioning is the consequence of a behaviour. – Thorndike's cats gained freedom and a piece of fish for escaping from the puzzle boxes. – Your dogs may receive food for sitting on command – A child may receive praise; a chance to ride the bike or a chance to watch TV for helping in the kitchen • Consequences like these increase the likelihood that a behaviour will be repeated are called REINFORCERS • In contrast, consequences that decrease the chances that a behaviour will be repeated are called PUNISHERS LAW OF EFFECT/ PRINCIPLES OF REINFORCEMENT • Thorndike summarized the influence of consequences in his LAW OF EFFECT as follows; – Behavior that brings about a satisfying effect (reinforcement) is apt to be performed again whereas – A behavior that brings a negative effect (punishment) is apt to be suppressed • Another name for law of effect is PRINCIPLES OF REINFORCEMENT by contemporary Psychologists. – Sometimes its difficult to tell whether a particular consequence will be reinforcing or punishing. Why? • Candy/ toffees might be reinforcing to all children. • Some may not like it, so for them it will not be rewarding. • Some children whom candy is initially reinforcing may eat too much of it, until it becomes neutral to them or even punishing. – We must therefore be careful when identifying consequences as reinforcers or punishers (Remember functional analysis) SUMMARY – LAW OF EFFECT • Behaviors that are followed by pleasant consequences will be strengthened, and will be more likely to occur in the future. • Conversely, behaviors that are followed by unpleasant consequences will be weakened, and will be less likely to be repeated in the future. OPERANT CONDITIONING- cont’d • If we were to judge by taste, then consumers of Guinness will consume less but that is not the case, why? – Obtain some reward – Social learning ( desire to be like Michael Powell) – Social influence (acceptance) OPERANT CONDITIONING- cont’d – For example, if a mother starts giving a boy his favorite snack every day that he cleans up his room, before long the boy may spend some time each day cleaning his room in anticipation of the snack. – In this example, the boy’s room-cleaning behavior increases because it is followed by a reward or reinforcer. – The next influential Scholar? SKINNER’S RESEARCH INTRO TO SKINNER • PAVLOV'S VIDEOS\B.F. SKINNER A FRESH APPRAISAL.flv 2 TERMS USED • CONTINGENCY – The probability that one event will follow the other – CONTIGUITY • Refers to the temporal relationship between the CS and US • The most important factor in constiguity is the timing SKINNER’S RESEARCH • Skinner Box • American psychologist B. F. Skinner designed an apparatus, now called a Skinner box, that allowed him to formulate important principles of animal learning. • An animal (rat, pigeon etc) placed inside the box is rewarded with a small bit of food each time it makes the desired response, such as pressing a lever or pecking a disc/key. – A device outside the box records the animal’s responses. SKINNER’S RESEARCH – (2) the box delivered only a • Like Thorndike’s puzzle box, small amount of food for each the Skinner box was a barren response, so that many chamber in which an animal reinforcers could be delivered in could earn food by making a single test session; and simple responses, such as – (3) the operant response pressing a lever or a circular required very little effort, so an response key animal could make hundreds or thousands of responses per • The Skinner box differed from hour. the puzzle box in three main • Because of these changes, ways: Skinner could collect much more – (1) upon making the desired data, and he could observe how response, the animal changing the pattern of food received food but did not delivery affected the speed and escape from the chamber; pattern of an animal’s behavior. PIGEON TAUGHT TO READ • PAVLOV'S VIDEOS\Operant conditioning.flv Skinners’ Pigeons playing table tennis • BF Skinner Foundation - Pigeon Ping Pong Clip.flv SKINNER’S RESEARCH • Skinner became famous not just for his research with animals, but also for his controversial claim that the principles of learning he discovered using the Skinner box also applied to the behavior of people in everyday life. – Skinner acknowledged that many factors influence human behavior, including heredity, basic types of learning such as classical conditioning, and complex learned behaviors such as language. – he however maintained that rewards and punishments control the great majority of human behaviors, and that the principles of operant conditioning can explain these behaviors. PRINCIPLES OF OPERANT CONDITIONING • Main principles to be considered are – reinforcement, – punishment, – shaping, – extinction, – discrimination, and – generalization. • REINFORCEMENT • Means “to strengthen” • Is a consequence that increases the probability that a behaviour will occur…Halonen and Santrock (1999:163) • Or simply any process/ event that strengthens a particular behavior—that is, increases the chances that the behavior will occur again. PRINCIPLES OF OPERANT CONDITIONING • • TWO TYPES OF REINFORCEMENT – POSITIVE, & NEGATIVE REINFORCEMENTS Positive Reinforcement, – • positive reinforcement, is a method of strengthening behavior by following it with a pleasant stimulus. Thus, a behavior is strengthened because a pleasant/ pleasurable stimulus followed it. • In experiments by Thorndike and Skinner; bar pressing and pecking behaviors are followed by food pellets which are positive • In human, positive reinforcers include basic items such as food, drink, sex, and physical comfort. • Other positive reinforcers include material possessions, money, friendship, love, praise, attention, and success in one’s career. !!PRINCIPLES OF OPERANT CONDITIONING • Negative reinforcement is a method of • Depending on the strengthening a behavior by following it circumstances, positive with the removal or omission of an reinforcement can strengthen unpleasant stimulus. either desirable or undesirable • There are two types of negative reinforcement: behaviors. – Escape and – Children may work hard at home – Avoidance –ve reinforcements or at school because of the praise they receive from parents • In escape (already present), performing and teachers for good a particular behavior leads to the performance. removal of an unpleasant stimulus. – For example, if a person with a – However, they may also disrupt headache tries a new pain reliever a class, or start smoking because and the headache quickly these behaviors lead to disappears, this person will probably attention and approval from use the medication again the next their peers. time a headache occur PRINCIPLES OF OPERANT CONDITIONING • Another e.g. for escape is that your father nags at you until you get tired/furious & you clean the garage. – Your (garage cleaning) response removes the unpleasant stimulus (nagging) – Torture works the same way… some lawyers or interrogators use it a lot – Medical Students learn in order to avoid failure or learn in order to obtain distinction… how do you classify the statement?? • In Avoidance (not present yet), people perform a behavior to avoid unpleasant consequences. – For example, drivers may take side streets to avoid congested intersections, – citizens may pay their taxes to avoid fines and penalties, – and students may do their homework to avoid detention. ADDITIONAL ILLUSTRATIONS – Reinforcements (+ve & -ve) • +ve reinforcement – BEHAVIOUR • Dress well – CONSEQUENCE • Compliments from loved ones/ friends – FUTURE BEHAVIOUR • -ve reinforcement – BEHAVIOUR • Taking Paracetamol • Paying taxes – CONSEQUENCE • Pain removed • Avoiding finds/ prosecution • Dressing behaviour increases – FUTURE BEHAVIOUR • Para taking behaviour increases • Tax paying increases How do you distinguish between Reinforcement and Punishment? Before then, what is Punishment? PRINCIPLES OF OPERANT CONDITIONING • Punishment – Is any event whose presence decreases the likelihood that ongoing behaviour will recur. – Or any event which when made contingent on a behaviour decreases the likelihood that that behaviour will recur. • there are two kinds of punishment, positive and negative. • Positive punishment involves reducing a behavior by delivering an unpleasant stimulus if the behavior occurs. – Parents use positive punishment when they spank, scold, or shout at children for bad behavior. • Societies use positive punishment when they fine or imprison people who break the law. (rules in the universities !!) • Negative punishment, also called omission, – involves reducing a behavior by removing a pleasant stimulus if the behavior occurs. – Parents’ tactics of grounding teenagers or taking away various privileges because of bad behavior are examples of negative punishment. – Is punishment an effective means of controlling behaviour? PRINCIPLES OF OPERANT CONDITIONING • Experiments have shown that, • Punishment may eliminate when used properly, desirable behaviors along with punishment can be a powerful undesirable ones. and effective method for – For example, a child who is scolded reducing behavior. for making an error in the classroom may not raise his or her hand again. • There are however some • May sometimes only minimize it and disadvantages; not eliminate it (e.g. Drivers & – become angry, aggressive, or highway police patrols). have other negative emotional • For these and other reasons, many reactions. psychologists recommend that – Does not teach the right punishment be used to control behaviour behavior only when there is no – May have some negative realistic alternative. physical problems (hurt) DISTINCTION BETWEEN REINFORMENT AND PUNISHMENT • REINFORCEMENT – Whether positive or negative results in an increase in behaviour. – For human, money, grades, hugs, kisses, praise and pat on the back are good examples. – Even an electric shock could be reinforcer. • Olds and Milners, 1954; Wise 1996 and Rolls, 1999 used MILD ELECTRICAL stimulation to in certain “ Pleasure centers” of the brain, • some of the animals chose to apply electric shock although they were very hungry • PUNISHMENT – Whether negative or positive results in decrease in behaviour • Negative reinforcement is also known as ESCAPE LEARNING OR AVOIDANCE LEARNING, because the responses lead to escape from or avoidance of some unpleasant events. LIVER PRESSING IN RAT • PAVLOV'S VIDEOS\Conditioned suppression of a rat's lever pressing.flv PRINCIPLES CONT’D; …SHAPING • Shaping is a reinforcement technique that is used to teach animals or people behaviors that they have never performed before. – The method (Successive approximation) is used whereby the teacher begins by reinforcing a response the learner can perform easily, and then gradually requires more and more difficult responses – For example, to teach a rat to press a lever that is over its head, the trainer can first reward any upward head movement, then an upward movement of at least one inch, then two inches, and so on, until the rat reaches the lever. – Skinner used it to teach pigeons to play pin- pong • Psychologists have used shaping to teach children with severe mental retardation – to speak by first rewarding any sounds they make, and then gradually requiring sounds that more and more closely resemble the words of the teacher. • Animal trainers use shaping to teach – elephants to stand on one leg, – tigers to balance on a ball, & – killer whales and dolphins to jump through hoops/play football etc. PRINCIPLES CONT’D; …SHAPING SHAPING & CHAINING • CHAINING BEHAVIOUR – To produce more complex sequence of behaviour, Psychologists use a procedure called chaining. The process is similar to shaping • what does the trainer do? – First, the animal learns the final behaviour for some reinforcements; then it learns the next- to- last behaviour, which is reinforced by the opportunity to perform the final behaviour. And so on. – A simplified example of response chaining is provided by Barnabus, a rat trained by psychologists Pierrel and Sherman, (1963) at Brown university. • By carefully working from the last response to the first, Barnabus was trained to make an ever-longer chain of responses to obtain a single food pellet. • When in top form, Barnabus was able to – – – – – – – – – – – climb a spiral staircase, cross a narrow bridge, climb a ladder, pull a toy car with chain, get into the car, pedal it to a second staircase, climb the staircase, wriggle through a tube, climb onto an elevator and descend to a platform, press a lever to receive a food pellet, and…start all over. SUPERSTITIOUS BEHAVIOUR • Reinforcement affects not only the last response we are interested in, but also other responses occurring shortly before. • This helps account for learning of many human superstitions. – If a golfer taps her club on the ground three times and then hits an unusually fine shot, the success of the shot reinforces not the correct swing but also the three taps. – It happens in other sporting activities as well. – If Kotoko/ Hearts went for Juju and they won, they are likely to go for another one before a crucial encounter in which they wish to win • During operant training, animals often develop similar unnecessary responses. – If a rat scratches its ear just before its bar press, it may continue to scratch its ear before ensuring bar press. • In this case, the bar press is all that is needed to produce food, but the animal may continue to “superstitiously” scratch its ear each time, as if this were also necessary. STIMULUS GENERALIZATION, DISCRIMINATION & EXTINCTION SAME AS IN CLASSICAL CONDITIONING … PLEASE READ !!! APPLICATION OF OPERANT CONDITIONING • Operant conditioning techniques have practical applications in many areas of human life. – Parents who understand the basic principles of operant conditioning can reinforce their children’s appropriate behaviors and punish inappropriate ones, and they can use generalization and discrimination techniques to teach which behaviors are appropriate in particular situations. – In the classroom, many teachers reinforce good academic performance with small rewards or privileges. – Companies have used it to improve attendance, productivity, and job safety among their employees. APPLICATION OF OPERANT CONDITIONING • Behavior therapists use shaping techniques to teach basic job skills to adults with mental retardation. – Therapists use reinforcement techniques to teach self-care skills to people with severe mental illnesses, such as schizophrenia, – and use punishment and extinction to reduce aggressive and antisocial behaviors by these individuals. • Psychologists also use operant conditioning techniques to treat drug addictions, stuttering, sexual disorders, marital problems, impulsive spending, eating disorders, and many other behavioral problems APPLICATION OF OPERANT CONDITIONING • USE OF OPERANT CONDITIONING IN PSYCHIATRIC HOSPITAL • Token Economy is the name if a common form of contingency contracting used in Psychiatric hospital. In Token economy the resident patients who perform desired activities earn plastic chips that can later be exchanged for some tangible benefit. It could also be used by psychotherapists to reinforce their clients. APPLICATION OF OPERANT CONDITIONING • Behavior Modification, psychological methods for treating maladjustment and for changing observable behavior patterns. • A landmark event for behavior modification took place when Pavlov's conditioning principles were extended to humans. – !!! In 1920 the American psychologists John B. Watson and Rosalie Rayner reported an experimental study in which an 11-month-old baby who had previously played with a white laboratory rat was conditioned to be fearful of the rat by associating a loud noise with the animal, a process known as pairing. !!!CLASSICAL APPLICATION OF OPERANT CONDITIONING • The psychologist Mary Cover Jones later performed experiments designed to reduce already established fears in children. • She found two methods particularly effective: – (1) associating a feared object with a different stimulus capable of arousing a positive reaction, and – (2) placing the child who feared a certain object with other children who did not. • This method is in use today by lots and lots of therapists where the child is reinforced after performing the desired response APPLICATION OF LEARNING THEORIES • Aversion therapy is used to break disabling bad habits. – An aversive stimulus, such as an electric shock, is given together with the “bad habit,” such as an alcoholic drink. – Repeated pairings result in changing the values of such stimuli from positive attraction to repulsion… operant APPLICATION OF OPERANT CONDITIONING • Applied behavior analysis is used to develop educational and treatment techniques for individuals people in need • Example of these individuals may include – retarded or disturbed children in a school or residential setting, – or adults in a psychiatric hospital or rehabilitation center. • Five essential steps must be considered: – (1) deciding what the individual can do to ameliorate the problem; – (2) devising a program to weaken undesirable behavior and strengthen desirable substitute behavior; – (3) carrying out the treatment program according to behavioral principles; – (4) keeping careful and objective records; and – (5) altering the program if progress can thereby be improved. ASSIGNMENTS • Compare classical and operant conditionings • Summarize the Cognitive views/ interpretations of Learning theories • SCHEDULES OF REINFORCEMENTS COMPARISON OF CLASSICAL & OPERANT CONDITIONING CLASSICAL CONDITION OPERANT CONDITION 1.Nature of Response Involuntary, reflex Spontaneous Voluntary 2. Reinforcement Occurs before response Occurs after response (conditioned stimulus pared (Response is followed by with UCS) reinforcing stimulus or events. 3. Role of Learner Passive (Response is elicited Occurs after response by US) (active response is followed by reinforcing stimulus or events. 4. Nature of Leaning Neutral stimulus becomes a C. Probability of making a S through association with an response is altered by UCS. consequence at follows it. ADDITIONAL INFORMATION OF REINFORCEMENT SCHEDULES OF REINFORMENTS SCHEDULES OF REINFORCEMENTS • Continuous reinforcement = a schedule of reinforcement in which every occurrence of a particular response is reinforced. • Partial Reinforcement = a situation in which the occurrence of response is sometimes followed by a reinforcement. • Skinner (1956) – Found that specific preset arrangements of partial reinforcement produced different patterns and rates of responding. – Together, these different reinforcement arrangements are called SCHEDULES OF REINFORCEMENT (is the delivery of reinforcer according to a preset pattern based on the number of responses or the time interval between responses). • There are four types of schedules – – – – FIXED RATIO VARIABLE RATION FIXED – INTERVAL SCHEDULE VARIABLE INTERVAL SCHEDULES OF REINFORCEMENTS • FIXED RATIO (FR). – Reinforcement occurs after a fixed number of responses • Example – Rat on 25 – to – 1 fixed ratio abbreviated FR 25) may have to press the bar 25 times in order to receive one food pellet. – Shaping is needed first; i. e the cat may have to be put on FR – 2, FR – 4 etc before FR – 25. • EVERYDAY LIFE example – Work for which you are paid for producing a specific number of items; – Paid ¢100 for producing a number of items (blocks, ice water etc) • VARIABLE – RATIO – Occurs when after an average number of responses, which varies from trial to trial. • Examples – A rat on a variable ratio – 20 schedule (VR – 20) would be reinforced after an average of 20 responses; presses 25 at first and 15 bar presses later before being reinforced. – Number of trials are unpredictable but over time repeated trials, the ratio of responses to reinforcers work out to predetermined averages. VARIABLE RATIO – CONT’D • This V – R – S produces high steady rates of responding with hardly any pauses b/n trials of after reinforcement. • Why do VRS produce such persistence responses? – One explanation is that although its impossible to predict which response will result in reinforcement; the more responses that are made the greater the likelihood of reinforcement. – The combination of the two factors can make some behaviors, such as gambling “ addictive” for some people. – Everyday example; toss of a dice, purchase of lottery ticket. The more u gamble, the more the opportunity. SCHEDULES OF REINFORCEMENTS – F I S. produces a pattern of • FIXED – INTERVAL (F.I) (interval responding in which the number of responses tend to increase as the time for the next reinforcer draws near. means reinforcement depends on passage of time instead of number of responses) – Reinforcement is delivered for the 1st response emitted after the preset time interval has elapsed. – A rat put on two – minute fixed interval schedule (FI – 2 min.) would receive no food pellet for any bar presses made during the first two minutes, whether it presses the bar twice or 100 times. – But the first bar press after the 2nd – minute interval has elapsed would be reinforced. • A rat on F. I – 10 minute schedule may go for several minutes without pressing the bar. As the 10th minute draws near it starts the bar pressing behavior vigorously. • DAILY LIFE EXAMPLE – If your lecturer organizes a quiz/ test every month ending, most students would wait a while and start to learn at the end of the month. – After test studying behavior drops. SCHEDULES OF REINFORCEMENTS • VARIABLE INTERVAL – Reinforcement occurs for the first response emitted after an average amount of time has elapsed, but the interval varies from trial to trial. – Length of time that must pass before reinforcement is delivered is unpredictable, but over a series of trials, it works out to be a predetermined average. – A rat on a V – I 30 seconds schedule might be reinforced on trial for the first bar press after only 20 seconds have elapsed, for the first bar press, – 1st after 50 seconds have elapsed on trial 2, and for the first bar press after 30 seconds have elapsed on trial 3. • This works out to an average of one reinforcement every 30 seconds. • Generally, the unpredictable nature tends to produce, moderate but steady rates of responding esp. when the average is relatively short. • Another e.g; trying to call a friend from GT to Space or vice versa – you try periodically but impossible to predict. SCHEDULES OF REINFORCEMENTS