Classical Conditioning: Learning to Predict Significant Events

Vocabulary flashcards generated from Chapter 4 of Learning and Memory covering key classical conditioning concepts, paradigms, models, neural substrates, and cellular mechanisms.

Classical (Pavlovian) conditioning

A form of learning in which an animal acquires the expectation that a given stimulus predicts a specific upcoming important event.

Unconditioned stimulus (US)

A cue that has some biological significance and that, in the absence of prior training, naturally evokes a response.

Unconditioned response (UR)

The naturally occurring response to an unconditioned stimulus (US).

Conditioned stimulus (CS)

A cue that is paired with an unconditioned stimulus (US) and comes to elicit a conditioned response (CR).

Conditioned response (CR)

The trained response to a conditioned stimulus (CS) in anticipation of the unconditioned stimulus (US) that the CS predicts.

Appetitive conditioning

Conditioning in which the unconditioned stimulus (US) is a desirable event (such as food delivery).

Aversive conditioning

Conditioning in which the unconditioned stimulus (US) is a disagreeable event (such as a shock or an airpuff to the eye).

Extinction

In classical conditioning, the process of reducing a learned response to a stimulus by ceasing to pair that stimulus with another, previously associated stimulus.

Compound conditioning

Conditioning in which two or more cues are present together, usually simultaneously, forming a compound CS.

Overshadowing

An effect seen in compound conditioning when a more salient cue within a compound acquires more association strength than does the less salient cue and is thus more strongly associated with the US.

Blocking

A two-phase training paradigm in which prior conditioning with one cue ($\text{CS}_1 \rightarrow \text{US}$) blocks later learning of a second cue when the two are paired together in the second phase of training ($\text{CS}_1 + \text{CS}_2 \rightarrow \text{US}$).

Rescorla–Wagner model

A formal model of conditioning based on the idea that changes in CS–US associations on a trial are driven by the discrepancy (or prediction error) between the animal's expectation of the US and whether the US actually occurred.

Prediction error

The discrepancy or error between an animal's expectation (or prediction) of the US and whether the US actually occurred.

Error-correction learning

Learning through trial and error to reduce the discrepancy (error) between what is predicted and what actually occurs.

Associative weight

In the Rescorla–Wagner model, a value representing the strength of association between a specific cue and the US.

Latent inhibition

A conditioning paradigm in which prior exposure to a CS retards later learning of the CS–US association during acquisition training.

US modulation theory

Any theory of conditioning that states the stimulus entering into an association is determined by a change in how the US is processed (e.g., Rescorla–Wagner model).

CS modulation theory

Any theory of conditioning that states the stimulus entering into an association is determined by a change in how the CS is processed (e.g., Mackintosh model).

Trial-level model

A theory of learning in which all the cues that occur during a trial and all the changes that result are considered a single event.

Delay conditioning

A conditioning procedure in which there is no temporal gap between the end of the CS and the beginning of the US and in which the CS co-terminates with the US.

Trace conditioning

A conditioning procedure in which there is a temporal gap between the end of the CS and the beginning of the US.

Interstimulus interval (ISI)

The temporal gap between the onset of the CS and the onset of the US.

Conditioned taste aversion

A conditioning preparation in which a subject learns to avoid a taste that has been paired with an aversive outcome, usually nausea.

Cerebellum

A brain region that lies below the cerebral cortex in the back of the head, responsible for the regulation and coordination of complex voluntary muscular movement, including classical conditioning of motor-reflex responses.

Purkinje cell

A type of large, drop-shaped, and densely branching neuron located in the cerebellar cortex.

Interpositus nucleus

One of the cerebellar deep nuclei from which the conditioned response output is generated in classically conditioned motor responses.

Inferior olive

Located in the brainstem, a nucleus of cells that conveys information about aversive stimuli (such as an airpuff US) up to both the interpositus nucleus and the cerebellar cortex.

Activity-dependent enhancement

Paired training of CS and US that produces an increase in the glutamate vesicles released from sensory neurons to motor neurons.

CREB-1

A protein inside neurons that activates genes in the neuron's nucleus that initiate the growth of new synapses.

CREB-2

A protein inside neurons that plays an opponent role to CREB-1 by inhibiting the actions of CREB-1.