“Standard Paradigm” for Classical Conditioning CS US CR Time Bell Food Drops of Saliva Delay Conditioning CS US CR Time Bell Food Drops of Saliva Trace Conditioning CS US CR Time Bell Food Drops of Saliva Simultaneous Conditioning CS US CR Time Bell Food Drops of Saliva Backwards Conditioning CS US CR Time Bell Food Drops of Saliva Conditioned Inhibition in Backwards Conditioning • Fear Conditioning – Tone ==> Shock – CR = Heart Rate Acceleration • Physiological Index of Fear • Standard Paradigm – HR Acceleration During Tone • Conditioned Fear Response • Backward Paradigm – HR Deceleration During Tone • Inhibition of Fear Response Contiguity vs. Contingency in Conditioning Rescorla (1967, 1988) • Contiguity – CS Co-Occurs with US • Contingency – CS Predicts US • Standard Paradigm – CS, US both Contingent and Contiguous • Delay, Trace Conditioning – CS, US Contingent but Not Contiguous • Simultaneous Conditioning – CS, US Contiguous but not Contingent • Backwards Conditioning, Extinction (Below Zero) – CS Predicts Absence of US Informational Value of the CS • When the US is Contingent on the CS, then the CS Provides Information About the US • Conditioning Occurs Because the CS Provides Information about US • Conditioning Does Not Occur When the CS is Not Informative What Happens When the Information in the CS is Redundant? Conditioned Emotional Responses • Tone CS  Footshock US • CR: Heart Rate Acceleration • Paradigmatic Variations – Standard Paradigm – Delay, Trace Paradigms – Simultaneous Paradigm – Backwards Paradigm • Safety Signal The Blocking Experiment (1) Kamin (1969) Initial Conditioning with Compound CS CS1 Noise CS2 Light US Shock Test Conditioning with Light CS Alone CS2 Light CR Fear Test The Blocking Experiment (2) Kamin (1969) Phase 1: Conditioning with Noise CS1 (1) Phase 2: Add Light CS2 Simultaneous with CS1 (2) CS1 Noise US Shock CS1 Noise CS2 Light US Shock 1 2 Test CS2 CR Light Fear The Blocking Effect Kamin (1969) CR Magnitude Test Response to Light 100 90 80 70 60 50 40 30 20 10 0 Noise Alone Compound Alone Noise then Compound Sequence of Conditioning Trials “Unblocking” the Blocking Experiment Phase 1: Conditioning with Simple CS Phase 2: Add Light CS2 Preceding CS1 CS1 Noise US Shock CS1 Noise CS2 Light US Shock 1 2 Test CS2 CR Light Fear Predictability, Surprise, and Conditioning Kamin (1969) • Conditioning Only Occurs When the US Surprises the Organism • Organism Searches Environment for Predictors of US • Irrelevant, Redundant Stimuli are Ignored • Classical Conditioning Involves the Formation of Expectations – CS predicts US Implications for S-R Learning Theory • Association by Contiguity – Association by Contingency • Empty Organism – Expectations, Surprise • Passive Organism – Actively Engaged in Predicting Events