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Learning and Conditioning Chapter 7 Copyright © 2010 Pearson Education Canada 7-1 Chapter Outline • Classical Conditioning • Classical Conditioning in Real Life • Operant Conditioning • Principles of Operant Conditioning • Operant Conditioning in Real Life • Learning and the Mind Copyright © 2010 Pearson Education Canada 7-2 -2 Basics of Learning • Learning: A relatively permanent change in behaviour (or behavioural potential) due to experience • Behaviourism: Approach that emphasizes the study of observable behaviour and the role of the environment as a determinant of behaviour • Conditioning: Basic kind of learning that involves associations between environmental stimuli and the organism’s responses Copyright © 2010 Pearson Education Canada 7-3 Classical Conditioning • Pavlov’s works with salivation in dogs led to discovery of learning principles • Classical conditioning: process by which a previously neutral stimulus acquires the capacity to elicit a response through association with a stimulus that already elicits a similar or related response Copyright © 2010 Pearson Education Canada 7-4 New Reflexes from Old • Unconditioned stimulus (US) – A stimulus that elicits a reflexive response in the absence of learning (e.g., food) • Unconditioned response (UR) – Reflexive response elicited by a stimulus in the absence of learning (e.g., salivation) Copyright © 2010 Pearson Education Canada 7-5 New Reflexes from Old • Neutral stimulus – Stimulus that does not yet produce a response – Regularly paired with unconditioned stimulus – Neutral stimulus becomes “conditioned” to elicit a response Copyright © 2010 Pearson Education Canada 7-6 New Reflexes from Old • Conditioned stimulus (CS) – An initially neutral stimulus that comes to elicit a conditioned response after being associated with an unconditioned stimulus (e.g., food bowl) • Conditioned response (CR) – A response that is elicited by a conditioned stimulus; occurs after the CS is associated with the US (e.g., salivation) Copyright © 2010 Pearson Education Canada 7-7 Principles of Classical Conditioning • Extinction – The weakening & eventual disappearance of a learned response – Occurs when the CS is no longer paired with the US – May experience spontaneous recovery of response after extinction Copyright © 2010 Pearson Education Canada 7-8 Principles of Classical Conditioning • Higher-order conditioning – A procedure in which a neutral stimulus becomes a conditioned stimulus through association with an already established conditioned stimulus Copyright © 2010 Pearson Education Canada 7-9 Principles of Classical Conditioning • Stimulus generalization – Tendency to respond to a stimulus that resembles one involved in original conditioning – Occurs when a stimulus that resembles the CS elicits the CR • Stimulus discrimination – Tendency to respond differently to two or more similar stimuli – Occurs when a stimulus similar to the CS fails to evoke the CR Copyright © 2010 Pearson Education Canada 7-10 What is Actually Learned? • Classical conditioning is most effective when stimulus to be conditioned precede the unconditioned stimulus • Conditioned stimulus becomes a signal for the unconditioned stimulus • To become a CS, a neutral stimulus must reliably signal or predict the US (Rescorla) Copyright © 2010 Pearson Education Canada 7-11 Classical Conditioning in Real Life • Learning to Like: – Classical conditioning involved in our positive emotional responses to objects, people, symbols, events, & places Copyright © 2010 Pearson Education Canada 7-12 Classical Conditioning in Real Life • Learning to Fear: – May learn to fear any stimulus that is paired with something that elicits pain, surprise, or embarrassment – Humans come biologically “prepared” to learn certain fears faster than others (evolutionary basis) • E.g., snakes, spiders, heights – Phobias: an exaggerated unrealistic fear of a specific situation, activity, or object Copyright © 2010 Pearson Education Canada 7-13 The Case of Little Albert • Classic Watson & Raynor (1920) experiment • Conditioned “Little Albert” to be afraid of white rats by pairing the neutral stimulus (rats) with an unconditioned stimulus (loud noises) • Days later, fear had also generalized to other furry objects Copyright © 2010 Pearson Education Canada 7-14 The Case of Peter • Jones (1924) and Watson demonstrated that fears can also be unlearned (e.g., Peter’s fear of rabbits) • Counterconditioning: process of pairing a conditioned stimulus with a stimulus that elicits a response that is incompatible with an unwanted conditioned response Copyright © 2010 Pearson Education Canada 7-15 Classical Conditioning in Real Life • Accounting for Taste: – Classical conditioning can explain how we learn to like & dislike many foods and odours – Researchers have taught animals to dislike foods/odours by pairing them with drugs that cause nausea or other unpleasant symptoms • E.g., Seligman & dislike of Béarnaise sauce • E.g., the “Garcia effect” & biological preparedness Copyright © 2010 Pearson Education Canada 7-16 Classical Conditioning in Real Life • Reacting to Medical Treatments: – Stimuli associated with drug treatments that produce nausea can become conditioned stimuli • E.g., chemotherapy treatments for cancer patients – Placebos may help to reduce pain & anxiety without side effects Copyright © 2010 Pearson Education Canada 7-17 Operant Conditioning • Operant conditioning – The process by which a response becomes more likely to occur or less so, depending on its consequences – Organism’s response operates or produces effects on the environment which influence whether response will occur again – Principles of Thorndike and B.F. Skinner Copyright © 2010 Pearson Education Canada 7-18 Consequences of Behaviour • Skinner argued that a response (“operant”) can lead to three types of consequences: 1. A neutral consequence neither increases or decreases the probability that the response will recur 2. Reinforcement strengthens the response or makes it more likely to recur 3. Punishment weakens the response or makes it less likely to recur Copyright © 2010 Pearson Education Canada 7-19 Reinforcement & Punishment • Reinforcement: the process by which a stimulus or event strengthens or increases the probability of the response that it follows • Punishment: the process by which a stimulus or event weakens or reduces the probability of the response that it follows Copyright © 2010 Pearson Education Canada 7-20 Primary & Secondary Consequences • Primary reinforcer – Stimulus that is inherently reinforcing, typically satisfying a physiological need (e.g., food) • Secondary reinforcer – Stimulus that has acquired reinforcing properties through association with other reinforcers • Primary punisher – Stimulus that in inherently punishing (e.g., electric shock) • Secondary punisher – Stimulus that has acquired punishing properties through association with other punishers Copyright © 2010 Pearson Education Canada 7-21 Reinforcement • Positive reinforcement – When a response is followed by the presentation or increase in intensity of a reinforcing stimulus; response becomes more likely to occur • Negative reinforcement – When a response is followed by the removal, delay, or decrease in intensity of an unpleasant stimulus; response becomes more likely to occur Copyright © 2010 Pearson Education Canada 7-22 Punishment • Positive punishment – When a response is followed by the presentation or increase in intensity of an unpleasant stimulus; response becomes less likely to occur • Negative punishment – When a response is followed by the removal, delay, or decrease in intensity of a pleasant stimulus; response becomes less likely to occur Copyright © 2010 Pearson Education Canada 7-23 Positive & Negative Consequences • Reinforcement: • Punishment: Copyright © 2010 Pearson Education Canada 7-24 Principles of Operant Conditioning • Paradigms often used a Skinner box – A cage equipped with a device that delivers food into a dish when an animal makes a desired response Copyright © 2010 Pearson Education Canada 7-25 Extinction • Extinction – The weakening and eventual disappearance of a learned response – Occurs when a response is no longer followed by a reinforcer – Spontaneous recovery of responses also may occur in operant conditioning Copyright © 2010 Pearson Education Canada 7-26 Generalization & Discrimination • Stimulus generalization – Tendency for a response that has been reinforced (or punished) in the presence of one stimulus to occur (or be suppressed) in the presence of another similar stimuli • Stimulus discrimination – Tendency of a response to occur in the presence of one stimulus but not in the presence of other, similar stimuli that differ from it on some dimension – May involve a discriminative stimulus Copyright © 2010 Pearson Education Canada 7-27 Schedules of Reinforcement • Continuous schedule of reinforcement – A schedule where a particular response is always reinforced • Intermittent (partial) schedule of reinforcement – A schedule in which a particular response in sometimes but not always reinforced – Can be fixed or variable, and involve the number of responses (ratio) or interval between responses Copyright © 2010 Pearson Education Canada 7-28 Shaping • When behaviours are not likely to occur spontaneously, may use shaping to teach to others (e.g., animals & children) • Shaping – An operant conditioning procedure in which successive approximations of a desired response are reinforced – Successive approximations: behaviours that are ordered in terms of increasing similarity or closeness to the desired response Copyright © 2010 Pearson Education Canada 7-29 Biological Limits on Learning • Principles of learning limited by genetic dispositions & physical characteristics • Instinctive drift – During operant learning, the tendency for an organism to revert to instinctive behaviour • E.g., animal training Copyright © 2010 Pearson Education Canada 7-30 Operant Conditioning in Real Life • Behaviour modification – The application of operant conditioning techniques to teach new responses or to reduce or eliminate maladaptive or problematic behaviour – Also called applied behaviour analysis • E.g., teaching tasks to mentally challenged adults • E.g., seat belt program in Quebec Copyright © 2010 Pearson Education Canada 7-31 The Pros of Punishment • Punishment can be effective when applied correctly: – Punishment most effective when it occurs immediately after the undesirable behaviour • E.g., radar versus photo radar tickets – The consistency of punishment is more important than the severity of punishment Copyright © 2010 Pearson Education Canada 7-32 The Cons of Punishment 1. People often administer punishment inappropriately 2. The recipient of punishment often responds with anxiety, fear, or rage 3. The effectiveness of punishment is often temporary and depends on the presence of the punisher 4. Most misbehaviour is hard to punish immediately 5. Punishment conveys little information 6. An action intended to punish may instead be reinforcing because it bring attention Copyright © 2010 Pearson Education Canada 7-33 Intrinsic & Extrinsic Rewards • Rewards may not work as planned as they can be misused, and may backfire – Extrinsic reinforcers: reinforcers that are not inherently related to the activity being reinforced – Intrinsic reinforcers: reinforcers that are inherently related to the activity being reinforced • Sometimes people become too reliant on extrinsic reinforcement and stop experiencing pleasure of doing something for its own sake Copyright © 2010 Pearson Education Canada 7-34 Learning and the Mind • Theorists argued that behaviour can be explained by specifying the behavioural ABC’s A. Antecedents (events preceding behaviour) B. Behaviour C. Consequences • But is behaviour more than just the ABC’s? Copyright © 2010 Pearson Education Canada 7-35 Latent Learning • Latent learning – A form of learning that is not immediately expressed in an overt response • Tolman & Honzik’s (1930) experiments with rats – Occurs without obvious reinforcement Copyright © 2010 Pearson Education Canada 7-36 Social Cognitive Theories • Social-cognitive theories – Theories that emphasize how behaviour is learned and maintained through observation and imitation of others, positive consequences, and cognitive processes such as plans, expectations, and beliefs – Learning is more than just standard conditioning procedures Copyright © 2010 Pearson Education Canada 7-37 Observational Learning • Observational learning – Process in which an individual learns new responses by observing the behaviour of another (a model) rather than through experience – E.g., Bandura’s bobo doll experiments Copyright © 2010 Pearson Education Canada 7-38 The Case of Media Violence • Does media violence make people behave more aggressively? – Meta-analyses show that the greater the exposure to violence in movies/TV, the stronger the likelihood of behaving aggressively – But some researchers argue that most people who view violence don’t become aggressive – Children & adults who are already aggressive are more drawn to violent media & more affected by them Copyright © 2010 Pearson Education Canada 7-39 Social-Cognitive View on Aggression • Social-cognitive theorists would say that there is a relationship between media violence & aggression – Repeated acts of aggression model behaviour; provide people with scripts; promote permissive beliefs about aggression; desensitization – BUT ... perceptions, interpretations, and personality dispositions intervene in determining our responses Copyright © 2010 Pearson Education Canada 7-40 End of Chapter 7 Copyright © 2010 Pearson Education Canada 7-41 -41