AP Psychology Unit 7Behavioral theory: Classical & Operant conditioningMods 21, 22 (Barron’s 6)

Chamberlain 2011-2012

The behaviorist approach •Behaviorist focus on OBSERVABLE BEHAVIORS•Try to explain the environmental/nurture causes

of human behaviors

•Choices for 1: A.predictableB.observableC.harmfulD.abnormal

1.

2.

Choices for 2:A.geneticB.environmentalC.unusualD.universal

What kind of learning is a behaviorist interested in? • Cognitivists focus on how we acquire and process knowledge • Behaviorists focus on how we LEARN behaviors

• Learning= long-lasting changes in one’s behavior due to experiences▫ “experience” includes:

receiving punishment or reward for a behavior observing and imitating a behavior associating stimuli with physical responses

• What kinds of experiences might lead to behavioral changes that are NOT due to “learning”? ▫ changes in behavior due to biological changes

illness hormonal changes of puberty or old age neural damage

Classical Conditioning: Pavlov and “Pavlovian Response” -- the contiguity model

Russian Dr. Ivan Pavlov, M.D. (1849-1936) studies of physiology of digestion in dogs led to discovery of conditioned reflexive responses

“Classical conditioning focuses on the learning of involuntary emotional or physiological responses such as fear, increase heartbeat, salivation, or sweating, which are sometimes called respondents or reflexes because they are automatic responses to stimuli” *

video clip The Office

Your turn!! p. 1-2 of conditioning packet

Contiguity: The idea that the more times you pair 2 stimuli (CS & US, the greater the learning

4 types of classical conditioning:

• Delayed: (NS/CS) first and continues when (US) is presented

• Trace: Present NS/CS first, take a break, present US• Simultaneous: Present NS/CS and US at exact same

time• Backward: US first, followed by NS/CS

Delayed is best, backward is least effective!

Let’s act it out!

1. Acquisition (learning)

2. Generalization:

3. Discrimination:

4. Extinction:

A.Stimulus similar to CS will elicit same CR

B.CR will stop after repeated exposure to CS without US

C.NS becomes CS and leads to CR (previously neutral stimulus becomes a conditioned stimulus able to elicit a reflexive response)

D.Animal learns to ignore stimuli that are similar to CS

a) If similar stimuli never accompany original US or sound of different bell NEVER paired with food

b) Original bell rung many times without exposure to foodc) Bell alone leads to salivationd) Different bells elicit salivation

1. C, c2. A, d3. D, a4. B, b

Answers

• Spontaneous recovery: Conditioned response reoccurs when exposed to CS AFTER extinction AND without any further training

• Second-order (AKA higher-order) conditioning: Pair CS with new US to train person/animal to have CR in response to new US• once dog has been trained to bite every time trainer says,

“Attack!”, owner adds a hand gesture to his command. Eventually, do will attack if he sees the hand gesture alone.

Rober Rescorla’s revised contingency model “The cognitive view of classical conditioning”

• the learning takes place more effectively when the US reliably predicts the presence of the NS

• If during training stage, food only sometimes accompanies bell, bell will not elicit desired response (salivation) US will not become CS

• This contrasts with Pavlov’s contiguity model which suggests it is merely the amount of times the pairings occur that matters, NOT that they occur reliably together

• Rescorla & Wagner add expectancy/cognition to conditioning

Conditioning = association = survival?• What would an evolutionary psychologist say about why we

learn through conditioning?▫ Taste aversion (Garcia effect) and evolutionary theory

rats were trained to associate a sound, sight, or taste (NS) with the nausea (UR) crated by radiation (US)

Would the sound NS, sight NS or taste NS become conditioned stimuli? Would the rats associate the nausea with the neutral stimuli?

YES—but only with the taste stimulus!!▫ Learning to associate smell, sound, sight, touch stimuli

with food, danger, mate promotes survival e.g.? Domjan’s Japanese quail studies

red light district male quail more virile, primed for sex

Are attitudes conditioned?•When words that elicit positive or negative

emotions are repeatedly paired with ideas or images, do we become conditioned to have positive or negative ‘visceral’ reaction to those ideas or images?▫Pokeman study (Olson and Fazio, 2001)

participants primed to associate negative or positive emotions w/ specific Pokeman characters because + or – words flashed repeatedly w/ specific characters

Practical applications of Pavlovian Response

In simple terms: you can train an animal (and a person) to respond in a desired way (perform a behavior or extinguish a behavior!) by training the person to associate desired (or undesired) behavior with a simple stimulus

stop coyote from eating sheep by poisoning sheep carcasses (aversive conditioning)

eliminate phobias through counter-conditioning (create positive association feelings with negative stimulus) and systematic desensitization – Behaviorist Joseph Wolpe teaches people to relax muscles while

exposed to incrementally scarier situations involving the phobia1920 John Watson experiment & aversive conditioning

“Baby Albert” video

DifferencesClassical=responde

nt (automatic) behavioral response to events/stimuli out of animal’s control

Operant=behavior that is learned due to association with consequences (person’s behavior “operates” on the environment and behavior is either reinforced OR extinguished due to punishment or reward)

Operant ConditioningThorndike & B.F. Skinner—Start with demonstration

What are the major similarities and differences between classical and operant conditioning?Similarities:

Both involve associationBoth involve acquisition, discrimination,

extinction, generalization, spontaneous recovery (Make sure you are able to identify the processes for each type!)

Practice: (a) Discrimination or (b) generalization? (c) Operant or (d) classical?

1. a rat that has had the behavior of pressing a bar reinforced begins pushing on other parts of his cage

2. a pigeon that has been trained through reinforcement to peck at red circles only when hearing a beep does not peck the red circle in absence of beep

3. a lab monkey that has learned to respond fearfully in the presence of a man in a white lab coat does NOT respond fearfully to the man in the blue coat who cleans his cage

1. cb 2. ca 3. daanswers

Operant conditioning (cont.)• Thorndike’s law of effect

▫ rewarded behavior is likely to recur (punished behavior NOT likely to recur)

▫ instrumental learning consequence of one’s behavior is instrumental to shaping FUTURE behaviors

• Skinner box (AKA operant chambers) studies▫ shaping non-reflexive behaviors through rewarding

successive approximations (almost doing the task—think Hot/Cold game)

▫ chaining: animals can be trained to do difficult, multi-step tasks (such as navigating through a maze or operating a complex machine) if rewarded for behaviors that are similar to desired behavior AND rewarded for each step of process

Operant conditioning (cont.)▫ Reward can be

gaining something positive (positive reinforcer) OR losing something negative (negative reinforcer)

Reinforce=increases likelihood behavior will recur Video clip : Sheldon conditions PennyReinforcement examples

+ reinforcementcookie, stickers, money, high grade, praise, positive touch, toy, extra t.v. time, extra “free time”,extra privileges, attention, given AFTER behavior occurs

Subject learns to associate behavior with receiving the desired reward

- reinforcement•If behavior occurs, remove pain, annoying stimulus (shock, loud noise, physical restraints, bright lights) Subject learns to associate behavior with eliminating an undesirable stimulus

•escape learning: subject learns to end/escape the yucky stimulus by behaving a certain way

•avoidance learning: subject learns to avoid a yucky situation all together

Remember: Just because someone thinks she is punishing you or reinforcing you doesn’t mean she actually is! Sometimes what is intended to be a reinforcer becomes a punishment and what is intended to be a punishment becomes a reinforcer!

Now you try: p. 3-4 of packet

Different kinds of reinforcers• primary:

▫ something that inherently gives the recipient pleasure (you don’t have to learn to like it) food, positive touch, warmth, water, rest, shelter...

• secondary▫ something that has no inherent value in itself but grows to be seen as

valuable because society has deemed it so good grades, points, stickers, praise, privileges

▫ generalized reinforcer= $ practical application seen in “token economies” used by parents, schools,

prisons...• Premack principle—essentially bribing! I can control you IF I

allow you to do a behavior you normally would do without reinforcement (it has instrinsic value to you) ONLY AFTER you do the behavior you don’t really want to do e.g. you may eat dessert only if you eat your broccoli

Skinner’s findings Video clip: Skinner’s pigeon study and schedules of reinforcement

Schedules of reinforcement:1. Continuous reinforcement—Reward

every time behavior occurs2. fixed-ratio schedule—reward comes after

consistent, fixed amount of behaviors3. fixed-interval schedule—reward occurs

after a fixed amount of time has passed after behavior occurs

4. variable-ratio schedules—reward appears in after random, unpredictable occurrences of behavior

5. variable-interval—reward appears after varying time intervals have passed after behavior occurs

Continuous vs. intermittent reinforcement—which is better to elicit desired behavior? continuous is better during the training intermittent is better once the behavior

has been learned—leads to persistence

A. slow, steady responses; know reward will eventually come, but no idea when!

B. leads to return to high rate of response after short pause after reinforcement; able to predict how often the behavior must occur before reward will arrive

C. leads to low rate of response; reinforcer loses its effectiveness

D. high rates of response, system used in slot machines; don’t know how often you’ll have to do behavior, but know reward will eventually arrive!

E. produces choppy start-stop pattern which increases as reward time draws nearer

1. C 2. B 3. E 4. D 5. AAnswers

Practical Applications of Operant Conditioning

Gambling—slot machines used variable interval schedules Behavior modification (B-mod)— “Extinguish an undesirable

behavior by removing the reinforcer and replace undesirable behavior with a desirable behavior by reinforcement.  It has been used on all sorts of psychological problems -- addictions, neuroses, shyness, autism, even schizophrenia -- and works particularly well with children” (Boeree 2006) see reading

Token economy (see reading)

Boeree, G. PhD. 2006. “Personality Theories. B.F. Skinner” http://webspace.ship.edu/cgboer/skinner.html

One caveat to operant conditioning...

•You can teach a dog tricks BUT you can’t make it go against its nature no matter how sweet the reward

•instinctive drift—the reward an animal gets from following its instinctive behavioral drive probably outweighs any reinforcements a trainer tries to use ▫pigs would rather bury the disks instead of

put them in a slot, even if given extrinsic reward for putting in slot