PSY 402 Theories of Learning Chapter 5 – The Role of Conditioning in Behavior

Is Conditioning Remembered?  Henderson showed that rats remembered an associated CS and shock 60 days later. Over time, both the US and CS become more generalized, memory for the stimulus is fuzzy.  Inhibition of fear is forgotten more quickly than excitatory conditioning. The inhibitor lost its ability to inhibit over time.  Memory reactivation – a reminder revives behavior, if given close to test time.

5.1 Conditioned fear 1 day and 60 days after conditioning More licking is suppressed with greater shock intensity

5.2 Conditioned inhibition is forgotten over time The inhibitor X has lost in inhibitory influence after 35 days. More inhibition

5.3 Forgetting can be reduced by a reminder The faster the rat runs out of the room, the more memory

Causes of Forgetting  Trace decay – the physical memory encoded in the brain decays, fades away. This seems plausible but is contradicted by memory reactivation, even years later.  Interference – learning new, conflicting information makes it difficult to retrieve previous learning.  Retrieval failure – the right cues are not there.

Two Types of Interference  Proactive interference – material that is learned first interferes with what is learned later.  Retroactive interference – material that is learned later interferes with previously learned material.  To decide whether it is proactive or retroactive, look at the subject of the test.

Importance of Context  The more similar the context between learning and retrieval, the more likely the material will be recalled. Rats trained to run from white to black compartment to avoid shock – flashing light is CS Distinctive contextual cues were odor, size, lighting. Performance decreased when the room was changed.

5.4 Forgetting also happens after a context change Faster running means more memory.

Renewal Effects  Changing the context during extinction has no impact on the rate of extinction.  However, after extinction of a learned association, the learning comes back when the context is changed. Returning the rats to the learning context acted as a new situation for them and learning returned. Changing to a new context also caused reactivation.

5.5 (A) Bouton-King design; (B) Results during extinction and testing same different

5.6 Associations that a tone CS (T) might have after extinction The meaning of the Tone depends on its context Only occurs if both the Tone and Context are active (present).

Temporal Cues  Spontaneous recovery may occur due to temporal cues related to passage of time. Changes in internal bodily state. Renewal occurs when a stimulus is outside its normal temporal context.  Reminders reduce both spontaneous recovery and renewal effects.  Relapse prevention in drug treatment.

5.7 (A) Spontaneous recovery; (B) The renewal effect Extinction cues have the same effect on both types of reactivation.

Additional Reactivation Effects  Reinstatement – occurs when the US is presented alone (without the CS). The previously extinguished CS produces a CR again.  Rapid reacquisition – the CS-UCS learning returns very quickly after extinction, due to the prior learning.

Counterconditioning  During counterconditioning, a new association is learned to a previously presented CS. Learning from the new pairing interferes retroactively with the previous learning. Systematic desensitization pairs relaxation with previous fear-eliciting stimuli.  Spontaneous recovery and renewal occur.

Other Paradigms are Affected  Table 5.1 lists other paradigms affected by context change and temporal renewal effects. Latent inhibition can be reduced by a context switch. Latent inhibition goes away with time.  Interference and memory effects are used to explain these experimental results.

Changing the Context  Due to the long time lapses (24 hrs typically), the CS cannot remain in short-term memory.  The context is the cue that retrieves the CS. This is retrieval-generated priming When the context is changed, there is no pre- exposure effect and learning is normal.  When CS preexposure and conditioning occur in different contexts, there is no latent inhibition.

5.8 The effects of time after latent inhibition The taste aversion is less inhibited after 12 days.

Context Modulates Behavior  Occasion setting occurs when the occasion (context cue) modulates responding to a CS.  The CS is not directly associated with the UCS but depends on presence of a second CS. The second CS 2 is not associated with the UCS either, but provides information about the UCS- CS 1 pairing. Example – a craving for a cigarette after dinner but not at other times.