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Classical Conditioning (also Pavlovian / Respondent Conditioning). Reflexes. Law of threshold Law of intensity-magnitude Law of latency *Note that the relationship is the reflex. Basic principles of classical conditioning. Ivan Pavlov 1849 - 1936 . The experiment: Pavlov Video.
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Classical Conditioning(also Pavlovian / Respondent Conditioning)
Reflexes • Law of threshold • Law of intensity-magnitude • Law of latency *Note that the relationship is the reflex
Basic principles of classical conditioning Ivan Pavlov 1849 - 1936
The experiment: Pavlov Video • Before • An unconditional stimulus (US) elicits an unconditional response (UR). Dry food in the dog's mouth elicits salivation • A conditional stimulus (CS) initially elicits an orienting response different from the UR. • During • The CS is paired with the US. • A short CS--US time interval • A relatively long US--US interval • After • The CS elicits a Conditional Response (CR). • The orienting response to the CS has habituated
Pavlovian Conditioning • Pavlovian Conditioning Example • Phobias • Advertising
PAVLOVIAN PARADIGM unconditional stimulus unconditional response elicits UCR UCS elicits CR CS conditional stimulus conditional response But what does mean?
Is the CR the same as the UR? • May differ • Does not follow laws of reflex • Can be opposite in direction
CS CS CS CS US US US US Temporal Relations and Conditioning Delay Conditioning Trace Conditioning Simultaneous Conditioning Backward Conditioning
BASIC PHENOMENA • ACQUISITION • EXTINCTION • STIMULUS CONTROL
Pavlov’s Law of Strength • Number of trials rule: The greater the number of CS-US pairings, the stronger the CR. • CS intensity rule: More intense CS's increase the rate of growth of the CR but do not seem to affect its asymptote. • US Intensity rule: More intense US's affect both the rate of growth and the asymptote of the CR. • CS-US interval rule: Longer CS-US intervals yield lower asymptotes of the CR. This rule highlights the importance of contiguity in classical conditioning. • CS-US contingency rule: The asymptote of the CR increases with the correlation between the CS and the US. This rule highlights the importance of contingency in classical conditioning.
What are the necessary and sufficient conditions for Pavlovian conditioning to occur? • Response Class • Temporal Relations • Contingency
Respondent Contingencies • Standard Procedure • P(UCS|CS) = 1 ; P(UCS|~CS) = 0 • Partial Reinforcement • 0 < P(UCS|CS) < 1 ; P(UCS|~CS) = 0 • Random Control • 0 < P(UCS|CS) = P(UCS|~CS) • Inhibitory CS • 0 < P(UCS|CS) < P(UCS|~CS) Pavlovian Conditioning
Contingency Table UCS ~UCS #UCSCS = A # CS = A + B P(UCS|CS) = A / (A+B) CS B A+B A ~CS D C+D C A+C B+D N |AD - BC| (A+B)(C+D)(A+C)(B+D) = Pavlovian Conditioning
Contingencies and Staddon’s Data SH ~SH = 20/30 = 2/3 = 10/30 = 1/3 = 10/30 = 1/3 = 20/30 = 2/3 P(S) P(~S) P(SH) P(~SH) 10 20 S 10 012 011 10 ~S 10 0 022 021 30 10 20 Pavlovian Conditioning
Staddon’s Data Pavlovian Conditioning
Contingencies and Staddon’s Data If S and SH were independent (“random control”): P (SH|S) = P (SH) or P (SH S) = P (SH) P(S) By definition: P (SH|S) = P (SH S) = #(SH and S) P(S) #S = 10/20 = 1/2 But: P (SH) = 10/30 = 1/3 So: P (SH|S) ≠ P (SH). Also, P (SH S) ≠ P (SH) P(S) 10/30 = 1/3 ≠ (1/3)(2/3) = 2/9 Pavlovian Conditioning
= X²1df= │011022 – 012021│ • N (011 + 012)(021 + 022)(011 + 021)(012 +022) Recall X² test for independence in contingency table with observed frequencies 0ij rc i=1 j=1 Where the Eij’s are the Expected Frequencies X²1df = (0ij – Eij) ² Eij For a 2 x 2 Table X²1df = N │011022 – 012021│² (011 + 012)(021 + 022)(011 + 021)(012 +022) Pavlovian Conditioning
For a 2 x 2 Table Χ²1df = N │011022 – 012021│² (011 + 012)(021 + 022)(011 + 021)(012 +022) SH ~SH E11 = (011 + 012)(011 + 021) N E12 = (011 + 012)(012 + 022) N E21 = (021 + 022)(011 + 021) N E22 = (021 + 022)(012 + 022) N S 011 + 012 012 011 021 022 021 + 022 ~S N 012 + 022 011 + 021 Pavlovian Conditioning
X1² = (13.33 – 10)² + (10 - 6.67)² 13.33 6.67 + (10 – 6.67)² + (3.33 -0)² 6.67 3.33 = 7.486 ≈ 7.5 X².95 = 3.84 1df = │(10(0) – (10)(10) │= 100 = 0.5 (20)(10)(20)(10) (20)(10) ² = 0.25 = X1² / 30, so X1² = 7.5 as above. S and Shock are not independent • For Staddon’s Data, the table is: 011 = 10 E11 = 13.33 012 = 10 E12 = 6.67 20 022 = 0 E22 = 3.33 021 = 10 E21 = 6.67 10 30 10 20 Pavlovian Conditioning
Conditioned Suppression • Conditioned Suppression • Useful in studying acquisition/extinction of conditioned fear • Animal trained to press lever using operant conditioning (usually VI schedule) • CS paired with an aversive US • DV = extent to which CS elicits a freezing (“fear”) response, suppressing lever pressing
cs S = Rcs Rcs+ Rcs cs cs S = 0.0 S = 0.5 Pavlovian Conditioning
P(UCS|CS) = P(UCS|~CS) = P(UCS~CS) = # (UCS~CS) P(~CS) # ~CS [P(CS) > 0] ~CS E UCSCS UCS~CS ~CS = E – CS = Context P(UCS|CS) = 1- P(~UCS|CS) P(UCS|~CS) = 1- P(~UCS|~CS) ~UCS Pavlovian Conditioning