Sarah Grison • Todd Heatherton • Michael Gazzaniga Psychology in Your Life FIRST EDITION Chapter 6 Learning © 2014 W. W. Norton & Company, Inc. Section 6.1 How Do the Parts of Our Brains Function? 6.1 What Are the Three Ways We Learn? • Learning: A change in behavior, resulting from experience – Central to almost all areas of human existence We Learn From Experience • Behaviorism: a formal learning theory from the early twentieth century – John Watson: focused on environment and associated effects as key determinants of learning – B. F. Skinner: designed animal experiments to discover basic rules of learning We Learn From Experience • Critical for survival • Adapt behaviors for a particular environment – Which sounds indicate potential danger? – What foods are dangerous? – When is it safe to sleep? We Learn in Three Ways 1. Non-associative learning 2. Associative learning 3. By watching others We Learn in Three Ways • Non-associative learning – Information about one external stimulus (e.g., a sight, smell, sound) – Habituation: A decrease in behavioral response after lengthy or repeated exposure to a stimulus – Especially if the stimulus is neither harmful nor rewarding • See Figure 6.2a next slide We Learn in Three Ways • Non-associative learning: information about one external stimulus (e.g., a sight, smell, sound) We Learn in Three Ways We Learn in Three Ways • Non-associative learning – Sensitization: An increase in behavioral response after lengthy or repeated exposure to a stimulus – Heightened preparation in a situation with potential harm or reward • See Figure 6.2b next slide We Learn in Three Ways We Learn in Three Ways • Associative learning – Understanding how two or more pieces of information are related We Learn in Three Ways • Associative learning • Classical conditioning: learn that two stimuli go together – Example: music from scary movies elicits anxiousness when heard • Operant conditioning: learn that a behavior leads to a particular outcome – Example: studying leads to better grades We Learn in Three Ways • Learning by watching others – Observational learning – Modeling – Vicarious conditioning The Brain Changes During Learning • Long-term potentiation (LTP) – The strengthening of synaptic connections between neurons – Recall that “cells that fire together, wire together” – Exposure to environmental events causes changes in the brain to allow learning Section 6.2 How Do We Learn by Classical Conditioning? 6.2 How Do We Learn by Classical Conditioning? • Familiar example: association between scary music in movies and bad things happening to characters Through Classical Conditioning, We Learn That Stimuli Are Related • Pavlov: Nobel Prize in 1904 for research on the digestive system • Observed dogs began to salivate as soon as they saw bowls of food – Salivating at the sight of a bowl is not automatic – Behavior acquired through learning by association • See Figure 6.3b next slide Through Classical Conditioning, We Learn Stimuli Are Related Through Classical Conditioning, We Learn That Stimuli Are Related • Classical conditioning – A type of learned response in which a neutral object comes to elicit a response when it is associated with a stimulus that already produces a response Through Classical Conditioning, We Learn That Stimuli Are Related • Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning : 1. Present unconditioned stimulus: evokes unlearned response 2. Present neutral stimulus: no response 3. Pair stimuli from Steps 1 and 2: learned response (conditioning trials) 4. Neutral stimulus alone will trigger learned response (critical trials) Through Classical Conditioning, We Learn That Stimuli Are Related • Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning – Step 1: presenting food causes salivary reflex – Unconditioned stimulus (US): A stimulus that elicits a response that is innate and does not require any prior learning (Food) – Unconditioned response (UR): A response that does not have to be learned, such as a reflex (Salivation) Through Classical Conditioning, We Learn That Stimuli Are Related • Step 2: clicking metronome is neutral stimulus – Neutral stimulus: anything seen or heard; must not associate with the unconditioned response Through Classical Conditioning, We Learn That Stimuli Are Related • Step 3 (conditioning trials): start of learning – Dog begins to associate US (food) and neutral stimulus (metronome) Through Classical Conditioning, We Learn That Stimuli Are Related • Step 4 (critical trials): Association learned – Metronome alone, without food, makes dog salivate • See Figure 6.3 next slide Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning Through Classical Conditioning, We Learn That Stimuli Are Related • Conditioned stimulus (CS): A stimulus that elicits a response only after learning has taken place • Conditioned response (CR): A response to a conditioned stimulus; a response that has been learned • See Scientific Thinking: Pavlov’s Experiments Reveal Learning by Classical Conditioning next slide Learning Varies in Classical Conditioning • Animals adapt via conditioning – Learning to predict outcomes leads to new adaptive behaviors Learning Varies in Classical Conditioning • Acquisition – Acquisition: The gradual formation of an association between conditioned and unconditioned stimuli. – Strongest conditioning occurs when CS is presented slightly before US • See Figure 6.5a next slide Acquisition, Extinction, and Spontaneous Recovery Learning Varies in Classical Conditioning • Extinction – Extinction: A process in which the conditioned response is weakened when the conditioned stimulus is repeated without the unconditioned stimulus • See Figure 6.5b next slide Acquisition, Extinction, and Spontaneous Recovery Learning Varies in Classical Conditioning • Spontaneous recovery – Spontaneous recovery: A process in which a previously extinguished response reemerges after the conditioned stimulus is presented again – Can occur after only one pairing following extinction – Response will weaken if CS-US pairings do not continue • See Figures 6.5c, 6.5d next slide Acquisition, Extinction, and Spontaneous Recovery Learning Varies in Classical Conditioning • Generalization, discrimination, and second-order conditioning – Stimulus generalization: Learning that occurs when stimuli that are similar but not identical to the conditioned stimulus produce the conditioned response – Animals respond to variations in CS Learning Varies in Classical Conditioning • Generalization, discrimination, and second-order conditioning – Stimulus discrimination: A differentiation between two similar stimuli when only one of them is consistently associated with the unconditioned stimulus • See Figure 6.6 next slide Generalization, Discrimination, and Second-Order Conditioning Learning Varies in Classical Conditioning • Generalization, Discrimination, and Second-Order Conditioning – Second-order conditioning: second CS becomes associated with first CS; elicits CR when presented alone – Neither US nor original CS present – Example: pairing black square (second CS) with metronome (first CS) so black square produces salivation (CR) on its own We Learn Fear Responses Through Classical Conditioning • Phobia – Acquired fear that is very strong in comparison to threat We Learn Fear Responses Through Classical Conditioning • The Case of Little Albert • Classical conditioning demonstrated in phobias: – Watson showed “Little Albert” various neutral objects (e.g., white rat, rabbit, dog, monkey, white wool) – Paired rat (CS) and loud clanging (US) until rat alone produced fear (CR) – Fear generalized to all similar stimuli • See Figure 6.7 next slide The Case of Little Albert We Learn Fear Responses Through Classical Conditioning • Counterconditioning – Counterconditioning: exposing subject to phobia during an enjoyable task – Systematic desensitization: exposure to feared stimulus while relaxing – CS -> CR1 (fear) connection replaced with CS -> CR2 (relaxation) connection Adaptation and Cognition Influence Classical Conditioning • Pavlov’s belief: Any two events presented together would produce learned association • By 1960s, data suggested that some conditioned stimuli more likely to produce learning Adaptation and Cognition Influence Classical Conditioning • Evolutionary Influences – Certain pairings more likely to be associated – Conditioned taste aversions: easy to produce with smell or taste cues – Auditory and visual stimuli: value for signaling danger • See figure 6.8 next slide Section 6.3 How Do We Learn by Operant Conditioning? 6.3 How Do We Learn by Operant Conditioning? • Operant conditioning – A learning process in which the consequences of an action determine the likelihood that the action will be performed in the future Animals Learn through the Outcomes of Their Actions • Thorndike’s Experiments Reveal the Effects of Action – Thorndike’s puzzle box: challenged fooddeprived animals to find escape – Trap door would open if animal performed specific action – Animal quickly learned to repeat behavior to free itself and reach the food • See Figure 6.10 next slide Thorndike’s Experiments Reveal the Effects of Action Animals Learn through the Outcomes of Their Actions • Thorndike’s general theory of learning – Law of effect: any behavior leading to a “satisfying state of affairs” likely to be repeated – Any behavior leading to an “annoying state of affairs” less likely to reoccur Learning Varies in Operant Conditioning • B. F. Skinner’s learning theory based on the law of effect – Animals operate on environments to produce effects – Reinforcer: stimulus occurs after response and increases likelihood of response reoccurring – Consequences determine likelihood of behavior in future • See figure 6.11 next slide Learning Varies in Operant Conditioning • Shaping – Shaping: operant-conditioning technique; reinforce behaviors increasingly similar to desired behavior • See Figure 6.12 next slide Shaping Learning Varies in Operant Conditioning • Reinforcers can be conditioned – Reinforcers that are necessary for survival, such as food or water, are called primary reinforcers – Events or objects that serve as reinforcers but do not satisfy biological needs are called secondary reinforcers Learning Varies in Operant Conditioning • Reinforcer potency – Premack principle: more valued activity can reinforce performance of less valued activity – Example: “Eat your spinach and then you’ll get dessert” Reinforcement and Punishment Influence Operant Conditioning • Reinforcement and punishment have opposite effects on behavior – Reinforcement: behavior more likely to be repeated – Punishment: behavior less likely to occur again Reinforcement and Punishment Influence Operant Conditioning • Positive and negative reinforcement – Both positive and negative reinforcement increase likelihood of a given behavior Reinforcement and Punishment Influence Operant Conditioning • Positive and negative reinforcement – Positive reinforcement: The addition of a stimulus to increase the probability that a behavior will be repeated – Example: feeding a rat after it has pressed a lever – Negative reinforcement: The removal of a stimulus to increase the probability that a behavior will be repeated – Example: taking a pill to get rid of a headache Reinforcement and Punishment Influence Operant Conditioning • Positive and negative punishment – Both positive and negative punishment reduce likelihood that behavior will be repeated Reinforcement and Punishment Influence Operant Conditioning • Positive and Negative Reinforcement – Positive punishment: The addition of a stimulus to decrease the probability that a behavior will recur – Example: electrical shock, speeding ticket – Negative punishment: The removal of a stimulus to decrease the probability that a behavior will recur – Example: loss of food, loss of privileges • See figure 6.14 next slide Reinforcement and Punishment Influence Operant Conditioning • Schedules of partial reinforcement – Continuous reinforcement: behavior reinforced each time it occurs – Fast learning, uncommon in real world – Partial reinforcement: behavior is occasionally reinforced – More common in real world Reinforcement and Punishment Influence Operant Conditioning • Schedules of partial reinforcement – How reinforcement given by how consistently given = four common schedules 1. Fixed schedule: predictable basis 2. Variable schedule: unpredictable basis 3. Interval schedule: based on passage of time 4. Ratio schedule: based on number of responses Reinforcement and Punishment Influence Operant Conditioning • Schedules of partial reinforcement – Fixed interval schedule (FI): Reinforcing the occurrence of a particular behavior after a predetermined amount of time since the last reward – Example: paycheck Reinforcement and Punishment Influence Operant Conditioning • Schedules of partial reinforcement – Variable interval schedule (VI): Reinforcing the occurrence of a particular behavior after an unpredictable and varying amount of time since the last reward – Example: pop quiz – More consistent response rates than fixed interval Reinforcement and Punishment Influence Operant Conditioning • Schedules of partial reinforcement – Fixed ratio schedule (FR): Reinforcing a particular behavior after that behavior has occurred a predetermined number of times – Example: paid by the completed task – Often yields better response rates than fixed interval Reinforcement and Punishment Influence Operant Conditioning • Schedules of partial reinforcement – Variable ratio schedule (VR): Reinforcing a particular behavior after the behavior has occurred an unpredictable and varying number of times – Example: slot machine • See Figure 6.15 next slide Schedules of Partial Reinforcement Reinforcement and Punishment Influence Operant Conditioning • Schedules of partial reinforcement – Partial-reinforcement extinction effect: behavior lasts longer under partial reinforcement than under continuous reinforcement • To condition behavior to persist: – Use continuous reinforcement initially – Slowly change to partial reinforcement Operant Conditioning Affects Our Lives • Parental Punishment Is Ineffective • To be effective, punishment must be – Reasonable – Unpleasant – Applied immediately – Clearly connected to the unwanted behavior Operant Conditioning Affects Our Lives • Parental Punishment Is Ineffective • Punishment can cause confusion – Wrongly applied after desirable behavior – Leads to negative emotions (e.g., fear, anxiety) – Fails to offset reinforcing aspects of the undesired behavior • Reinforcement teaches desirable behavior • See Figure 6.16 next slide Parental Punishment Is Ineffective Operant Conditioning Affects Our Lives • Behavior modification – Behavior modification: operant conditioning replaces unwanted behaviors with desirable behaviors – Token economies: opportunity to earn tokens (secondary reinforcers) for completing tasks and lose tokens for behaving badly – Tokens later traded for objects or privileges – Gives participants sense of control Biology and Cognition Influence Operant Conditioning • Behaviorists believed conditioning principles explained all behavior. In reality, reinforcement explains only a certain amount of human behavior Biology and Cognition Influence Operant Conditioning • Dopamine activity affects reinforcement – Dopamine has a biological influence on reinforcing value – Drugs that block dopamine’s effects disrupt operant conditioning – Drugs that enhance dopamine activation increase reinforcing value of stimuli Biology and Cognition Influence Operant Conditioning • Biology constrains reinforcement – Some animal behaviors hardwired – Difficult to learn behaviors counter to evolutionary adaptation – Conditioning most effective when matched to animal’s biological predispositions Biology and Cognition Influence Operant Conditioning • Learning without reinforcement – Insight learning: A sudden understanding of how to solve a problem after a period of either inaction or thinking about the problem Section 6.4 How Do We Learn by Watching Others? 6.4 How Do We Learn by Watching Others? • Behaviors we learn by watching others – Mechanical skills, social etiquette, situational anxiety, attitudes about politics and religion • Three ways we learn by watching 1. Observational learning 2. Modeling 3. Vicarious conditioning Three Ways We Learn through Watching 1. Observational learning: The acquisition or modification of a behavior after exposure to at least one performance of that behavior – Examples: foods safe to eat, objects and situations to fear – Powerful adaptive tool • See Figure 6.20 next slide Three Ways We Learn through Watching Three Ways We Learn through Watching • Bandura’s research reveals learning through observation – Observation of aggression: Bandura’s Bobo doll study – Group 1: watched film of adult playing quietly with Bobo, an inflatable doll – Group 2: watched film of adult attacking Bobo – Viewers of aggression were more than twice as likely to play aggressively Three Ways We Learn through Watching • Learning through modeling • Modeling: The imitation of behavior through observational learning – More likely to imitate actions of attractive, high-status models similar to ourselves • See Figure 6.22 next slide Learning Through Modeling Three Ways We Learn through Watching • Learning through vicarious conditioning • 3. Vicarious conditioning: Learning the consequences of an action by watching others being rewarded or punished for performing the action – Rewarded behavior more imitated – Punished behavior less imitated • See Figure 6.23 next slide Watching Others Results in Cultural Transmission • Meme: shared piece of cultural knowledge – Similar to genes, selectively passed across generations, can spread much faster – Animals also show this kind of knowledge sharing • See Figure 6.24 next slide Watching Others Results in Cultural Transmission Biology Influences Observational Learning • Mirror neurons – Fire in your brain and other person’s brain every time you watch them engaging in an action – Does not always lead to imitation – Scientists are still debating mirror neurons’ function