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6.1 What Are the Three Ways We Learn?
• Learning: a relatively enduring change in behavior due to 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 learning2. Associative learning3. By watching others
• Let’s look at these on the following slides
We Learn in Three Ways
1. Non-associative learning: information about one external stimulus (e.g., a sight, smell, sound)
We Learn in Three Ways
• 1a. Habituation: exposure to a stimulus for a long time, or repeatedly, leads to a decrease in behavioral response– Especially if the stimulus is neither harmful nor
rewarding
• See Figure 6.2a on the next slide . . .
We Learn in Three Ways
We Learn in Three Ways
• 1b. Sensitization: exposure to a stimulus over a long time, or repeatedly, leads to an increase in behavioral response– Heightened preparation in a situation with
potential harm or reward
• See Figure 6.2b on the next slide . . .
We Learn in Three Ways
We Learn in Three Ways
• 2. Associative learning: understanding how two or more pieces of information are related
We Learn in Three Ways
• 2a. Classical conditioning: learn that two stimuli go together– Example: music from scary movies elicits
anxiousness when heard
• 2b. Operant conditioning: learn that a behavior leads to a particular outcome– Example: studying leads to better grades
We Learn in Three Ways
• 3. 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
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 sight of a bowl is not automatic– Behavior acquired through learning by association
• See Figure 6.3b on the next slide . . .
Through Classical Conditioning, We Learn Stimuli Are Related
Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning
• Classical conditioning: learning begins with a stimulus that naturally elicits a response– Much like a reflex
Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning
• Four key steps:1. Present unconditioned stimulus: evokes
unlearned response2. Present neutral stimulus: no response3. Pair stimuli from Steps 1 and 2: learned response
(conditioning trials)4. Neutral stimulus alone will trigger learned
response (critical trials)
• Let’s look at this on the next slide
Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning
• Step 1: presenting food causes salivary reflex– Unconditioned stimulus (US): nothing is learned
about the stimulus (e.g., food)– Unconditioned response (UR): an unlearned
behavior, like a simple reflex (e.g., salivation)
Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning
• Step 2: clicking metronome is neutral stimulus– Neutral stimulus: anything seen or heard; must
not associate with the unconditioned response
Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning
• Step 3 (conditioning trials): start of learning– Dog begins to associate US (food) and neutral
stimulus (metronome)
Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning
• Step 4 (critical trials): association learned– Metronome alone, without food, makes dog
salivate
• See Figure 6.3 on the next slide . . .
Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning
Pavlov’s Experiments Reveal the Four Steps in Classical Conditioning
• Conditioned stimulus (CS): after conditioning, previously neutral stimulus (NS) reliably produces unconditioned response (UR)
• Conditioned response (CR): behavior only after conditioning; usually weaker than unconditioned response
Learning Varies in Classical Conditioning
• Animals adapt via conditioning• Learning to predict outcomes leads to new
adaptive behaviors
Acquisition, Extinction, and Spontaneous Recovery
• Acquisition: gradual formation of learned association between CS and US to produce CR– Strongest conditioning occurs when CS is
presented slightly before US
• See Figure 6.5a on the next slide . . .
Acquisition, Extinction, and Spontaneous Recovery
Acquisition, Extinction, and Spontaneous Recovery
• Extinction: CS no longer predicts arrival of US• Sometimes associations are no longer
adaptive• See Figure 6.5b on the next slide . . .
Acquisition, Extinction, and Spontaneous Recovery
Acquisition, Extinction, and Spontaneous Recovery
• Spontaneous recovery: original association between CS and US is relearned• Can occur after only one pairing following
extinction– Response will get weaken if CS-US pairings do not
continue
• See Figure 6.5d on the next slide . . .
Acquisition, Extinction, and Spontaneous Recovery
Generalization, Discrimination, and Second-Order Conditioning
• Stimulus generalization: stimuli similar, but not identical to, CS that produces CR– Animals respond to variations in CS
• See Figure 6.6 on the next slide . . .
Generalization, Discrimination, and Second-Order Conditioning
Generalization, Discrimination, and Second-Order Conditioning
• Stimulus discrimination: differentiate between similar stimuli; one is consistently associated with US and the other is not
• See Figure 6.7 on the next slide . . .
Generalization, Discrimination, and Second-Order 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
The Case of Little Albert• Classical conditioning demonstrated in
phobias:– 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 6.8 on the next slide . . .
The Case of Little Albert
Counterconditioning
• Classical conditioning techniques valuable in treating phobias
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
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
Cognitive Influences
• Through classical conditioning, animals predict events– Easier when CS before US rather than after US– Easier when CS is more unexpected or surprising
6.3 How Do We Learn by Operant Conditioning?
• Human behaviors are purposeful• Operant conditioning: relationship between
behavior and consequences
We Learn Effects of Behavior Through Operant Conditioning
• Operant conditioning: animals operate on environments to produce effects
• Consequences determine likelihood of behavior in future
Thorndike’s Experiments Reveal the Effects of Action
• Thorndike’s puzzle box: challenged food-deprived 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 on the next slide . . .
Thorndike’s Experiments Reveal the Effects of Action
Thorndike’s Experiments Reveal the Effects of Action
• 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:– Reinforcer: stimulus occurs after response and
increases likelihood of response reoccurring
• Believed that behavior occurs because reinforced
Shaping
• Shaping: operant-conditioning technique; reinforce behaviors increasingly similar to desired behavior
• See Figure 6.12 on the next slide . . .
Shaping
Reinforcers Can Be Conditioned
• Primary reinforcers: satisfy biological needs, necessary for survival (e.g., food, water)
• Secondary reinforcers: serve as reinforcers, do not satisfy biological needs; established through classical conditioning
Reinforcer Potency
• Some reinforcers are more powerful• 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
Positive and Negative Reinforcement
• Both positive and negative reinforcement increase likelihood of a given behavior
Positive and Negative Reinforcement
• Positive reinforcement: addition of stimulus that increases probability behavior will reoccur– Example: feeding a rat after it has pressed a lever
• Negative reinforcement: removal of stimulus that increases likelihood of given behavior– Example: taking a pill to get rid of a headache
Positive and Negative Reinforcement
• Both positive and negative punishment reduce likelihood that behavior will be repeated
Positive and Negative Reinforcement
• Positive punishment: addition of stimulus decreases probability of behavior being repeated – Example: electrical shock, speeding ticket
• Negative punishment: removal of stimulus decreases probability of behavior being repeated – Example: loss of food, loss of privileges
Schedules of Reinforcement
1. Continuous reinforcement: behavior reinforced each time it occurs– Fast learning, uncommon in real world
2. Partial reinforcement: behavior is occasionally reinforced – More common in real world
Schedules of Reinforcement
• How reinforcement given x how consistently given = four common schedules1. Fixed schedule: predictable basis2. Variable schedule: unpredictable basis3. Interval schedule: based on passage of time4. Ratio schedule: based on number of responses
• See Figure 6.15 on the next slide . . .
Schedules of Reinforcement
Schedules of Reinforcement
1. Fixed interval schedule (FI): reinforcement after fixed amount of time– Example: paycheck
2. Variable interval schedule (VI): reinforcement after unpredictable amount of time– Example: pop quiz– More consistent response rates than fixed interval
Schedules of Reinforcement
3. Fixed ratio schedule: reinforcement after fixed number of responses – Example: paid by the completed task– Often yields better response rates than fixed interval
4. Variable ratio schedule: reinforcement after variable number of responses – Example: slot machine
Schedules of 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
• Imagine a parent says no to a candy bar, so child throws a tantrum– Parent yells, “If you don’t stop screaming, you’re
going to get a smacked bottom!”
• Will this approach get the desired behavior?
Parental Punishment Is Ineffective
• To be effective, punishment must be:– Reasonable– Unpleasant– Applied immediately– Clearly connected to the unwanted behavior
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 on the next slide . . .
Parental Punishment Is Ineffective
Behavior Modifications
• Behavior modification: operant conditioning replaces unwanted behaviors with desirable behaviors
• Most unwanted behaviors can be unlearned
Behavior Modifications
• 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
Dopamine Activity Affects Reinforcement
• Biological influence on how reinforcing something is– Drugs that block dopamine’s effects disrupt
operant conditioning– Drugs that enhance dopamine activation increase
reinforcing value of stimuli
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
Learning Without Reinforcement
• Tolman argued that reinforcement impacts performance more than knowledge acquisition– Ran rats through complex mazes to obtain food– Cognitive map: maze-specific mental
representation that Tolman believed each rat developed
Learning Without Reinforcement• Three groups of rats traveled maze–Group 1: no reinforcement–Group 2: reinforcement every trial–Group 3: reinforcement only after first 10
trials• See Figure 6.19 on the next slide . . .
Learning Without Reinforcement
Learning Without Reinforcement
• Latent learning: learning without reinforcement
• Group 1: slow, many wrong turns• Group 2: faster, fewer errors each trial• Group 3: –Before reinforcement, similar to Group 1–After reinforcement, better than Group 2
Learning Without Reinforcement
• Insight learning: solution suddenly emerges after delay; type of problem solving
• Reinforcement does not fully explain but predicts behavior’s repetition
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 learning2.Modeling3.Vicarious conditioning
Three Ways We Learn Through Watching
1. Observational learning: individual acquires or changes behavior after viewing it at least once– Examples: foods safe to eat, objects and situations
to fear
• Powerful adaptive tool• See Figure 6.20 on next slide . . .
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
Learning Through Modeling
2. Modeling: imitation of observed behavior• More likely to imitate actions of attractive,
high-status models similar to ourselves• See Figure 6.22 on the next slide . . .
Learning Through Modeling
Learning Through Vicarious Conditioning
3. Vicarious conditioning: learning about consequences by watching others– Rewarded behavior more imitated– Punished behavior less imitated
• See Figure 6.23 on the next slide . . .
Learning Through Vicarious Conditioning
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 on the 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 still debating mirror neurons’ function
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