Classical conditioning Reminder of basic effect What makes for effective conditioning? How does Classical conditioning work?

Classical conditioning

Reminder of basic effect

What makes for effective conditioning?

How does Classical conditioning work?

Basic effectIf Unconditioned Stimulus Unconditioned Response

(meat powder) (salivation)

then pair

Conditioned stimulus with the unconditioned stimulus (bell) (meat powder)

then eventually

Conditioned stimulus conditioned response(bell) (~salivation)

Who didn’t know this already?

Why is Pavlov famous?

Who didn’t know this already?

“Acts of recollection, as they occur in experience, are due to the fact that one movement has by nature another that succeeds it in regular order”

--Aristotle

Who didn’t know this already?

Are there foods that make you salivate?

Who didn’t know this?

If Unconditioned Stimulus--> Unconditioned Response (sour taste) (face)

then pair

Conditioned stimulus with the unconditioned stimulus(sight of pickle) (sour taste)

then eventually

Conditioned stimulus--> conditioned response(sight of pickle) (~face)

Measurement• You can’t answer questions effectively

without an experimental method• It’s not enough to say “she makes a face”

• How many times must she eat pickles?• What if sometimes I offer a pickle-shaped candy?• Can any stimulus be associated with any response?• WHY does she make the face?

-Here comes that stupid food-Associates sight of pickle with sourness-Associates sight of pickle with face

Lots of questions you could ask

• What makes an effective CS and US?

• How might classical conditioning work?

• Belongingness• E.g., Taste barfing, sight shock

CS CR

CS CR

NOTE THIS WAS ACTUALLY DONE WITH RATS

CS CR

CSCR

Belongingness is observed in humans, too. Fear conditioning to snakes/spiders vs. flowers/mushrooms (dv = GSR)

What makes effective CS & US

• Novelty of CS or US

• Bell alone, then bellfood– Bell associated w/ background– Bell associated w/ no food

• Food alone, then bell food

How does CC work?

Importance of one stimulus being conditional on another.

How does CC work?

• Learning that one stimulus is conditional on the other means that you’re learning about the environment (food always follows bell)

• This implies that if one stimulus is not conditional on the other, you won’t get learning.

• Prediction 1: If you present CS and US randomly, you shouldn’t get learning.

• Prediction 2: Animals should ignore stimuli that don’t have predictive value.

Predictive value--blocking

Group 1: Light food LightTone

food Tone food

Group 2: LightTone

food Tone food

Training 1 Training 2 Test

Learning = bad

Learning = good

The point of blocking

The animal only learns what tone means if tone carries

predictive information, even if tone predicts food.

Rescorla Wagner Model

VA=VA

Where A= a particular USVA=Associative strength = a threshold of activation

In blocking, asymptote for learning (has been Reached during initial training, so further training no learning.

increases as the intensity of the US increases

Recorla-Wagner

The power of the Rescorla-Wagner model is that it allows new predictions, some of them unintuitive.

E.g., in blocking, you get no learning, despite repeated pairings. It’s also possible to lose associative strength despite repeated pairings.

Lose associative strength

Training Test

Light->foodTone->food

Light & tone->food

0

20

40

60

80

100

120

140

1st tentrials

2nd 3rd 4th

Test

Arb

itra

ry u

nits

What does the learning look like?

• S-R theory

• S-S theory

Stimulus substitution theory (S-R)

US URCR

CS

Association

But this doesn’t account for higher-order conditioning. . .

Higher-order conditioning

light food

then

bell light

Answer

The dog will salivate to bell.

S-S theory (rather than S-R)

US URCR

CS

Association

EnvironmentInternal representation

US

CS

Response

Which is right?

Early views favored S-R learning, and viewed the organism in Classical

conditioning as passive.

More recent views favor the S-S view, in which the organism seeks out

information about the environment.

Rigor allows prediction

Note how different this enterprise is than my casual observation of my daughter.

Application to humans?

Application to humans?

• Food aversions

• Bed wetting

• Advertising

• Drug tolerance & addiction

Bedwetting

Wet Call Bedwetting Alarm/Pad Wet Call is a moisture sensing bed pad/alarm specifically designed for habitual bed wetters… The Wet Call bed pad is placed under the child and the alarm sounds when the pad’s sensor strips detect moisture.

http://www.bedwettingstore.com/bedwetting-wetcall.htm

If Unconditioned Stimulus Unconditioned Response (alarm) (waking)

then pair

Conditioned stimulus with the unconditioned stimulus (full bladder) (alarm)

then eventually

Conditioned stimulus conditioned response(full bladder) (~waking)

If Unconditioned Stimulus--> Unconditioned Response (sight of babe) (positive evaluation)

then pair

Conditioned stimulus with the unconditioned stimulus(sight of cigarettes) (sight of babe)

then eventually

Conditioned stimulus conditioned response(sight of cigarettes) (~positive evaluation)

Opponent process model of drug tolerance

Initially, the drug causesa big response, e.g., hypothermia

The body struggles to get backto homeostasis (raise body temp.)

Habituating to the drug meansthose processes (hyperthermia) kick in before the drug acts.

Opponent process model of drug tolerance

If Unconditioned Stimulus Unconditioned Response (opiate) (hyperhermia)

then pair

Conditioned stimulus with the unconditioned stimulus (sight of drug) (opiate)

then eventually

Conditioned stimulus conditioned response(sight of drug) (~hyperthermia)

Are there really such opponent processes?

Opiate Administration Opiate WithdrawalHypothermia HyperthermiaDecrease blood pressure Increase blood pressurePeripheral vasodilation Peripheral vasoconstrictionRespiratory depression yawning, pantingRelaxation restlessnessAnalgesia Pain sensitivity

Predictions:

Craving for drug is an attempt to get back to homeostasis:Craving is caused by Conditioned stimuli

e.g.: being offered “taste”seeing a friend shoot uptalking about drugsbeing in locale where you used to shoot upseeing “works”

Likelihood of overdose is higher in unfamiliar surroundingDrug rehab. should take place in typical drug-using setting