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Learning
Unit 6
Intro
• Animals live by instinct/genetic code (think salmon)
• Humans have instinct, but also think/change with environment
• 3½ learning types…
• Classical conditioning
• Operant conditioning
• Observational learning
• Language (?)
• Learning = relatively permanent behavior change due to experience
• We learn by association = connecting events that occur in succession
• Good – birthday song  cake!
• Bad—bright flash  lightning!
• Habituation = lessening of a response due to familiarity
Classical conditioning
st
(1
type)
• Ivan Pavlov – godfather of behaviorism
• Behaviorism – focus on observable, measurable behaviors
• Noticed dogs naturally salivate at sight of food…
• …wondered if they’d unnaturally salivate to something else.
• Rang a bell before food. Again, again, again, …
• …until dogs salivated at sound of bell.
• Tubes in salivary glands measured the response.
Cont. (these show up as test questions)
• 4 parts to classical conditioning…
1. UCS – unconditioned stimulus = natural stimulus (this biologically
happens)
• Food
2. UCR – unconditioned response = natural response (this biologically
happens)
• Salivate
3. CS – conditioned stimulus = unnatural stimulus associated w/ UCS
• Bell
4. CR – conditioned response = response (always same as UCR)
• Salivate
5 conditioning processes
1. Acquisition – initial learning of stimulus-response
2. Extinction – diminished response of UCS & CS (food & bell)
3. Spontaneous recovery – re-emergence of association after a “time
out”
4. Generalization – response to a similar CS (dogs respond to piano)
5. Discrimination – NOT responding to a stimuli b/c it’s too different
(dogs don’t respond to horn honk)
John B. Watson
• Another main behaviorist (along with Pavlov)
• Worked with Little Albert
• Placed baby down, placed white rat on his lap
• Baby was not scared
• Snuck up behind Albert, clanged two metal bars  BANG!
• Scared Albert, he cried
• Did it again, again, again
• Albert would then cry at sight of the rat
• UCS, UCR, CS, CR?
Cont.
• Then, added a rabbit, dog, fur coat, toy.
• Generalization – furry critter-like  Albert cried
• Discrimination – NOT furry critter-like  Albert was okay
• Ethical issues?
• Do no harm
• Informed consent?
• Debriefing?
• Epilogue – Watson was fired, married his assistant, worked for
Maxwell House & started the “coffee break”
Pavlov’s legacy
• Behaviorists – anything mental doesn’t matter; may over-estimate this
• Cognitive processes are at play
• Behaviorists say animals are only machines that react
• Martin Seligman experiment on learned helplessness
• Caged dogs, shocked them
• They cowered in fear
• Opened-the cage
• They still cowered in fear
• They had learned/think they are helpless
• People do this with depression…what we think matters
Cont.
• Biological predispositions are at play too
• Animals are hard-wired by biology
• We’re not just machines that react, but good/bad at things
• Rats – awesome taste associations
• Humans – good taste associations too (food poisoning?)
• Pigs picking up “$” & depositing in piggy bank
• Men – seem attracted to color…
• …red
• Legacy of Pavlov
• Classical conditioning can be applied often (addiction, bed-wetting)
• An abstraction like “learning” can be objectively studied
Operant conditioning
nd
(2
type)
• Difference from Classical Cond. – C.C. is biological & automatic, O.C.
involves a decision
• E. L. Thorndike – behaviorist, 1st in operant cond.
• Law of Effect = a reinforced behavior is likely to be repeated
• Made “puzzle boxes”, put cats in them…
• …cat had to figure his way out, get a treat.
• …came up with learning curve
Operant (cont.)
• B. F. Skinner – behaviorist, 2nd big name in operant (likely the biggest
name in behaviorism)
• Made “Skinner boxes” where animals could manipulate things, get
reinforcements. Typical box…
• …food, water, light, sound, lever, shocker
• Skinner was obsessed with measuring/graphing results
• Shaping = slowly getting the animal to do what’s desired, step-by-step
• Discriminative stimulus = animal can distinguish one from another
Cont.
• Punishment = discourages a behavior
• Reinforcement = encourages a behavior
• Positive reinforcement = encourages behavior by adding
something good
• Ex.: roll over, get a cookie
• Negative reinforcement = encourages behavior by removing
something bad
• Ex.: hit the snooze button, stops the annoying alarm
• Primary reinforcers = natural & unlearned (food, no pain)
• Conditioned or secondary reinforcers = learned by attaching to a
primary
Schedules of reinforcement
• Answers, “When will reinforcement occur?” 4 types:
• Fixed ratio = after set number of behaviors
• Ex.: you get paid after each box you ship
• Variable ratio = after random number of behaviors
• Ex.: you win after unknown number of slot machine tries
• Fixed interval = after set amount of time (time on a clock)
• Ex.: you get paid every hour
• Variable interval = after random amount of time
• Ex.: you catch a fish after unknown amount of time
Skinner’s legacy (operant)
• Until death, Skinner shunned the cognitive. We’re robots.
• Evidence says he may be wrong (5 ways)…
1. Latent learning – learning that doesn’t show up until later.
• Edward Tolman – rats in a maze. 2 groups…(a) reward at each
correct turn, (b) reward at the end.
• Group (b) did better b/c they formed a mental map.
2. Insight learning – learning that comes all-at-once. You’re stuck, then
suddenly, ah-hah! “I got it!”
Cont.
3.
Intrinsic motivation – remember Seligman and learned
helplessness? A dog/person who says, “My actions matter! I can deal
with this!” is intrinsically motivated.
• AKA: internal locus of control
4.
Extrinsic motivation – A dog/person who says, “My actions don’t
matter. I give up,” is extrinsically motivated.
• AKA: external locus of control
5.
Biological pre-dispositions – certain animals are good at certain
things. Remember pigs picking up “$ chips” for food?
Skinner’s lasting works
• His vision—teach via computer w/ points & rewards.
• Sports—we can learn/master skills step-by-step.
• Work—reinforcement should be specific & immediate.
• Home—parents can shape good/desired behavior.
• Self—we can put ourselves on a “point system” to do better.
• Review…what’s the difference between classical & operant?
Observational Learning
rd
(3
type)
• Def. = learning by watching others without our own experience
• Mirror neurons support this. While watching others do something,
brain neurons fire like we are doing it.
• Ex.: empathy—mirror neurons help us feel others’ pain
• Ex.: yawning is contagious, hard to smile when seeing a frown
• Albert Bandura is tops in observational learning
• Bobo doll experiment
• Kids watch adults punch it…
• …then kids do it. Modeling matters.
Takeaways
• Business – modeling is great for training
• Role models matter, can be very positive to kids.
• Hypocritical parents (“Do as I say, not as I do.”)…
• …grow kids who do as the parents do.
• Abusive parents more likely to raise abusive kids/adults.
• Nature or nurture? Monkey study leans toward nurture.
• TV – 75 year old will watch 9 years of TV
• By middle school, 8,000 murders and 100,000 violent acts
• Unpunished 74% of time
No pain 58% of time
• “Justified” 50% of time
Attractive person 50% of time
• 1950s…TV came to U.S., homicide went up (ditto for other nations)
• 2 results: imitation & desensitization (we mimic, it doesn’t bother us)
Language learning
th
(4
type)
• We can learn through words…
• …we hear & we learn.
• …we read & we learn.
• Neither is experiencing it firsthand (like C.C. or O.C.)…
• …neither is observing anything (like obs. learn.)…
• …but we still learn through words.