3. What are the CS and US?

(shock)

(tone)

After one or two pairings…

(CS)

Blood pressure

Heart Rate

Stress Hormones

Hypoalgesia

Freezing

(CR’s)

Conditioned Suppression

Suppression Ratio

a = responses during the CS

b = responses prior to the CS

a(a + b)

After 10 Tone-Shock trials: a = 3; b = 20. 3/(3+20) = 0.13

On first Tone-Shock trial: a = 30; b = 30. 30/(30+30) = 0.50

Rayner with “Little Albert”

Conclusions

• 4. Effects of CS-US pairings can be measured directly or indirectly by their effects on another behavior

4. What are the CS and US?

Paired versus Unpaired

Conclusions

• 5. Effects of CS-US pairings must be compared to a proper control group

5. What are the CS and US?

No AgeDifferencesIn Eye-Blink

Age-Related DeclineWhy?

Deficits Appear in “Middle Age”

“Good”vs.

“Bad”Conditioners

H.M.is

“good”

Lower Brain Volume—Alzheimers!

CognitiveEnhancers

Rabbit Data

Conclusions

• 6. Conditioning experiments have value as a diagnostic tool

6. What are the CS and US?

Rabbit Eyelid

Taste Aversion

Conclusions

• 1. Conditioned behaviour is “evoked” by the CS, it is not “chosen” by the organism [Reminder]

• 7. What constitutes a pairing depends on the response system (no optimal ISI)

Blue Gouramis

Highly Territorial But Needs to Mate

7. What are the CS and US?

Conclusions

• 8. Pavlovian Conditioning has can have adaptive value

Darwin’s Finches

What determines the form of the CR?

Stimulus Substitution

Conditioned Opponent

Behavior Systems

Stimulus Substitution (the CS takes the place of the US)

• Pavlov: UR = Salivation, CR = Salivation

• Cocaine: UR = Activity, CR = Activity

• Cyclophosamide: UR & CR = immune suppression.

• Autoshaping: CR for water = Closed beak, CR for grain = Open beak

However…

• Fear conditioning: CR = freezing, UR = activity

• CS can determine form of CR: Lever licked, UR = eat pellet

Form of CR depends on CS

CR= sniff, social contact, approach

However…

• Fear conditioning: CR = freezing, UR = activity

• CS can determine form of CR

• Interval between CS and US also matters– Long delay: General search CR– Short delay: Focal search CR

Timberlake Behavior Systems Theory

The CS and US engage the same “behavior system” – e.g., appetitive, sexual, defensive

The form of the CR depends on the length of the delay between CS and US.

Overt CR is flexible – depends on situation

Increased GeneralActivity

Increased Activity atUS site

SexualArousal