Learning • • • • Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Definition of Learning Learning is “any relatively permanent change in behavior brought about through experience.” – Conditioning: • The acquisition of specific patterns of behavior in the presence of well-defined stimuli. Two Types of Conditioning • Classical (C.C.): – a response naturally elicited by one stimulus comes to be elicited by a different, formerly neutral stimulus • Operant (O.C.): – behaviors are emitted (in the presence of specific stimuli) to earn rewards or avoid punishments Learning • • • • Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Pavlov It all starts with a REFLEX It all starts with a REFLEX Automatic It all starts with a REFLEX Unconscious It all starts with a REFLEX Involuntary It all starts with a REFLEX Inborn REFLEX Causes Stimulus Response REFLEX Leads to Stimulus Response REFLEX Elicits Stimulus Response REFLEX Causes Stimulus Puff of air to the eye Response Blink REFLEX Causes Stimulus Light in the eye Response Pupillary Constriction REFLEX Causes Stimulus Pain Response Withdrawal REFLEX Causes Stimulus Meat Powder in mouth Response Salivation REFLEX Causes Stimulus Electric Shock Response Fear REFLEX Unconditioned Stimulus Unconditioned Response REFLEX UCS UCR Click ?? Some stimuli do nothing Click Some stimuli do nothing Footsteps Some stimuli do nothing Metronome Some stimuli do nothing Rabbit Some stimuli do nothing Hiss Some stimuli do nothing Neutral Stimulus Some stimuli do nothing NS Learning involves repeated pairing Learning involves repeated pairing UCS UCR Learning involves repeated pairing NS + UCS UCR After repeated pairing NS + CS UCS UCR CR After repeated pairing CS CR After repeated pairing CS CR Learning involves repeated pairing NS Hiss + UCS Puff UCR Blink After repeated pairing NS Hiss + CS UCS Hiss Puff CR UCR Blink After repeated pairing CS Hiss CR Blink After repeated pairing CS Hiss CR Blink REFLEX Causes Some stimuli do nothing Learning involves repeated pairing Learning involves repeated pairing Learning involves repeated pairing After repeated pairing After repeated pairing After repeated pairing After repeated pairing the organism has formed an association between the once neutral stimulus and the unconditioned stimulus. An example QuickTime™ and a MPEG-4 Video decompressor are needed to see this picture. It all begins with a REFLEX Learning Classical Conditioning Reflexes A relatively simple, automatic, stimulus-response sequence that is mediated by the CNS • Unconditioned stimulus (UCS). – Elicits a response in the absence of learning. • Unconditioned response (UCR). – The reflexive response to a stimulus in the absence of learning. UCS UCR • No learning here. Organism is born with this reflex Operant Conditioning Ecological Learning Observational Learning New Reflexes from Old Learning Classical Conditioning • A neutral stimulus is then regularly paired with an unconditioned stimulus. Operant Conditioning Ecological Learning Observational Learning New Reflexes from Old • Conditioned stimulus (CS). – • An initially neutral stimulus that comes to elicit a conditioned response after being paired with an unconditioned stimulus. Conditioned response (CR). – – – A response that is elicited by the conditioned stimulus. Occurs after the CS is associated with the US. Identical to the US Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Classical Conditioning Diagram Learning Classical Conditioning Operant Conditioning Ecological Learning Reflex Observational Learning NS + UCS UCR (BELL) (PUFF) (BLINK) CS CR (BELL) (BLINK) Classical Conditioning Learning Classical Conditioning Operant Conditioning Prior to conditioning UCS (food powder in mouth) UCR (salivation) Neutral stimulus (tone) Neutral stimulus CS (tone) CR (salivation) Conditioning UCS (food powder) After conditioning CS (tone) CR (salivation) Ecological Learning Observational Learning In Watson’s Little Albert study, the conditioned response was 1. Salivation 2. Nausea 3. Fear 0% 1 0% 2 0% 3 10 In Pavlov’s original experiments, the neutral stimulus was the 1. Sound of the footsteps 2. Taste of the meat powder 3. Sight of the white lab coat 0% 1 0% 2 0% 3 10 In Pavlov’s original experiments, the conditioned stimulus was the 1. Sound of the footsteps 2. Taste of the meat powder 3. Sight of the white lab coat 0% 1 0% 2 0% 3 10 When you first went to the dentist as a child, you heard the highpitched whine of the drill, and had no reaction. After you’ve had your first filling, the drill causes a nervous reaction - cold hands, increased heart rate and blood-pressure, etc. The drill became the 1. Conditioned Stimulus 2. Unconditioned stimulus 3. Conditioned Response 0% 1 0% 2 0% 3 10 From the last question, the anxiety is the 1. Neutral Stimulus 2. Conditioned Stimulus 3. Conditioned Response 0% 1 0% 2 0% 3 10 The neutral stimulus was the 1. Sight of the dentist 2. Sound of the drill 3. Anxiety 0% 1 0% 2 0% 3 10 Although you’ve never been afraid of flying, the last time you flew the plane went into a nosedive for nearly a minute. Now when you fly, you get extremely nervous. In this example, flying is the 1. Conditioned response 2. Conditioned stimulus 3. Unconditioned response 0% 1 0% 2 0% 3 10 From the previous example, what is the unconditioned response? 1. The sight of the airplane 2. Salivating 3. Fear 0% 1 0% 2 0% 3 10 Basic Rules of Conditioning Learning Classical Conditioning • The more association trials, the better the conditioning • CS and US must be closely linked in time • Physically intense stimuli are conditioned more easily • Some responses are more easily conditioned than others Operant Conditioning Ecological Learning Observational Learning Contingency Learning Classical Conditioning Contingency Operant Conditioning Ecological Learning Observational Learning Classical Conditioning Learning Classical Conditioning Extinction – Operant Conditioning Ecological Learning Observational Learning Weakening of a conditioned association in the absence of an unconditioned stimulus or reinforcer Spontaneous recovery – Reappearance of an extinguished conditioned response after a time delay Acquisition, Extinction, and Spontaneous Recovery Learning Classical Conditioning Spontaneous Recovery Operant Conditioning Ecological Learning Observational Learning Classical Conditioning Learning Classical Conditioning Operant Conditioning Ecological Learning • Higher order conditioning • Stimulus generalization • Discrimination learning Observational Learning Higher-Order Conditioning Learning Classical Conditioning • A neutral stimulus can become a conditioned stimulus (CS) by being paired with an existing conditioned stimulus (CS). Higher-Order Cond. Operant Conditioning Ecological Learning Observational Learning Stimulus Generalization Learning Classical Conditioning • Occurs when a new stimulus that resembles the conditioned stimulus, elicits the conditioned response. Stimulus Generalization Operant Conditioning Ecological Learning Observational Learning Stimulus Discrimination Learning Classical Conditioning • The tendency to respond differently to two or more similar stimuli. • In classical conditioning, it occurs when a stimulus similar to the condition stimulus (CS) fails to evoke a conditioned response (CR). Discrimination Operant Conditioning Ecological Learning Observational Learning Real-Life Examples Learning Classical Conditioning • • • • • • Drug overdoses Smoking: environmental cues Systematic desensitization Advertising: sex appeal Taste aversion Conditioning and the immune system Examples Operant Conditioning Ecological Learning Observational Learning Abnormal Behavior and CC Learning Classical Conditioning Operant Conditioning Ecological Learning NS + UCS UCR (Dog) (Pain from Bite) CS CR (Dog) (Fear) (Fear) Observational Learning Learning • • • • Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Operant Conditioning Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning The consequences that follow a behavior make that behavior more or less likely to occur in the future. •Make behavior more likely – Reinforcement •Make behavior less likely - Punishment Operant Conditioning Learning Classical Conditioning Operant Conditioning Ecological Learning •Operant behaviors are different from the responses involved in classical conditioning –They are voluntarily emitted –Those involved in classical conditioning are elicited by stimuli. Observational Learning ALL reinforcers increase the likelihood that a response will become more frequent Reinforcement Learning Classical Conditioning • What is a reinforcer? – Definition: a reinforcer is any stimulus which, when delivered to a subject, increases the probability that a subject will emit the most recent response. • Primary reinforcers, e.g., food • Secondary reinforcers, e.g., praise – One can only know if a stimulus is a reinforcer based on the increased probability of occurrence of a subject’s behavior Operant Conditioning Ecological Learning Observational Learning Reinforcement Learning Classical Conditioning Positive reinforcers – Operant Conditioning Ecological Learning Observational Learning Stimulus, contingent on a particular behavior, that increases the probability of that response happening again Negative reinforcers – Removal of an unpleasant stimulus, contingent on a particular behavior, that increases the probability of that response happening again Examples of Consequences Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Positive Negative Behavior Reinforcement Give food for correct response Remove shock for correct response Increases Punishment Give shock for incorrect response Remove food for incorrect reponse Decreases Reinforcement Learning Primary reinforcers – Reinforcers, such as food and sex, that have an innate basis because of their biological value to an organism Secondary reinforcers – Stimuli, such as money or tokens, that acquire their reinforcing power by their learned association with primary reinforcers (also called conditioned reinforcers) Classical Conditioning Classical Conditioning Operant Conditioning Ecological Operant Conditioning Learning Observational Learning Ecological Learning Observational Learning Schedules of Reinforcement Learning Classical Conditioning Operant Conditioning Continuous reinforcement – Reinforcement schedule in which all correct responses are reinforced Partial reinforcement – Reinforcement schedule in which some, but not all, correct responses are reinforced (also called intermittent reinforcement) Ecological Learning Observational Learning Schedules of Reinforcement Learning Classical Conditioning Ratio schedules – Provide reward after a certain number of responses Interval schedules – Provide reward after a certain time interval Fixed Ratio (FR) Variable Ratio (VR) Fixed Interval (FI) Variable Interval (VI) Operant Conditioning Ecological Learning Observational Learning Schedules of Reinforcement Learning Classical Conditioning Operant Conditioning Fixed Ratio (FR) Rewards appear after a certain set number of responses Variable Ratio (VR) e.g. factory workers getting paid after Fixed Interval every 10 cases of (FI) product are Variable Interval completed (VI) Ecological Learning Observational Learning Schedules of Reinforcement Learning Classical Conditioning Operant Conditioning Ecological Learning Fixed Ratio (FR) Rewards appear after a certain number of responses, but that Variable Ratio number varies from (VR) reinforcer to reinforcer Fixed Interval (FI) e.g. slot machine Variable Interval pay-offs (VI) Observational Learning Schedules of Reinforcement Learning Classical Conditioning Rewards appear after Fixed Ratio (FR) a certain fixed amount of time, regardless of number Variable Ratio of responses, as long (VR) as the response Fixed Interval occurs during the (FI) interval. Variable Interval (VI) e.g. weekly or monthly paychecks Operant Conditioning Ecological Learning Observational Learning Schedules of Reinforcement Learning Classical Conditioning Rewards appear after Fixed Ratio (FR) a certain amount of time, but that amount varies from trial to Variable Ratio trial, as long as the (VR) response occurs during the interval. Fixed Interval (FI) e.g. random visits Variable Interval from the boss who delivers praise (VI) Operant Conditioning Ecological Learning Observational Learning Schedules of Reinforcement Learning • Simple reinforcement schedules produce characteristic response patterns • Steeper lines mean higher response rates • Ratio schedules produce higher response rates than interval schedules Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Partial Reinforcement Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning A rat is given a food pellet every time it presses a bar 7 times. 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 2 0% 3 0% 4 10 An instructor gives an exam every Friday afternoon. 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 2 0% 3 0% 4 10 Another instructor gives pop quizzes at random times. 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 0% 2 3 0% 4 10 A migrant worker gets $3.00 for every ten baskets of cherries he picks. 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 2 0% 3 0% 4 10 Every time Mary puts her Charlie Card into the turnstile, she is allowed on the T 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 0% 2 3 0% 4 10 A salesman makes calls on 14 potential customers per day. 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 2 0% 3 0% 4 10 You call your best friend from high school, and keep getting a busy signal. 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 0% 2 3 0% 4 10 John stands at the T stop and peeks around the corner to see if the train is coming. 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 2 0% 3 0% 4 10 Coming to work on Friday results in a paycheck for work completed during the week 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 0% 2 3 0% 4 10 A friend of yours wants you to study more, so she comes to your room with chocolate cookies every so often. If she finds you studying then you get a cookie. 1. 2. 3. 4. Fixed Ratio Variable Ratio Fixed Interval Variable Interval 0% 1 0% 2 0% 3 0% 4 10 Persistence of Avoidance Learning Learning Classical Conditioning • Negatively reinforced responses show slower extinction than positively reinforced responses Operant Conditioning Ecological Learning Observational Learning Problems with Punishment Learning Classical Conditioning • Too uninformative – only tells learner what NOT to do, not what TO do. • Tends to work well only when punisher present (unlike reinforcement) - this often accidentally leads to a partial schedule of reinforcement. • Tends to cause fear in learner - (who stops ALL behavior) – classically conditioned response • Constant effectiveness requires escalation • Often the easiest and quickest consequence, but rarely the most effective at changing behavior. Operant Conditioning Ecological Learning Observational Learning Alternatives to Punishment Learning Classical Conditioning Operant Conditioning • Extinction • Reinforcing preferred activities –Premack principle • Shaping Ecological Learning Observational Learning Shaping Learning Classical Conditioning • To teach complex behaviors, may need to reinforce successive approximations of a desired response. • For example, training animals, getting children to make their beds. Operant Conditioning Ecological Learning Observational Learning Shaping Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning QuickTime™ and a decompressor are needed to see this picture. The Death of Behaviorism Tolman’s Latent Learning Learning • • • • Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Limitations to Pavlov’s and Skinner’s Theories of Learning Learning Classical Conditioning • Preparedness – some associations are learned more easily than others (e.g. associating taste with nausea is easier than associating noise with nausea). – One-trial learning – Spider and snake phobias are easier to condition than flower and rock phobias. – Species specific behaviors sometimes hard to modify Operant Conditioning Ecological Learning Observational Learning Conditioned Taste Aversions Learning Classical Conditioning Operant Conditioning Biological tendency in which an organism learns to avoid food with a certain taste after a single experience, if eating it is followed by illness Ecological Learning Observational Learning Application of psychology: Learning the wrong things Learning Classical Conditioning • What is superstitious behavior? – non-contingent reinforcement – examples of superstitions • Learned helplessness – the cessation of all behavior as a result of intense punishment – dog’s behavior in electrified cage – wife’s behavior in an abusive marriage Operant Conditioning Ecological Learning Observational Learning Learning • • • • Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning QuickTime™ and a YUV420 codec decompressor are needed to see this picture. Social Learning Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning • Social cognitive theories emphasize how behavior is learned and maintained: – through observation and imitation of others, – positive consequences, – cognitive processing such as plans, expectations, and beliefs. • Observational learning involves learning new responses by observing the behavior of another rather than through direct experience. Bandura, Ross, and Ross (1963). Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning • Nursery school children watched a film of 2 men (Johnny and Rocky) playing with toys. • Johnny refuses to share and Rocky hits him, ending up with all the toys. • Children who watched the video were significantly more violent than children in a control group. Observational Learning • Bandura’s Bobo doll study Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning Bandura’s Results Learning Classical Conditioning Operant Conditioning Ecological Learning Observational Learning