The cognitive chess game:

Excitation and Inhibition

Starting point for what would appears to be a highly complex set of learning rules. Not really that bad as long as you realize that from the Pavlovian point of view that stimuli (CSs) have the potential to be inhibitory or excitatory, that is the stimulus signal response decrease if the CS is inhibitory and response

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1) Excitation: Normal forward conditioning in which CS is paired with UCS and the CR resembles the UCR. CS elicits or Excites the production of the CR. Inhibition is a type of classical conditioning in which the conditioned stimulus (CS) becomes a signal for the absence of the unconditioned stimulus (UCS). In Pavlov's world all stimuli are excitatory or inhibitory depending on the history the CS has had with the UCS. EXAMPLES: We have already noted these phenomenon when discussing Classical, SPC, HOC, and extinction. Page 3

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Types of Inhibition and excitation:1a

A1. External Inhibition during excitation

Temporary disruption of conditioned response (CR) due to presentation of external stimuli. (non-associative) Example: Presenting a novel stimulus (noise, smoke, light) will immediately inhibit, albeit, temporarily the production of a CR. Novel stimulus inhibits CR. External Inhibition.

A2. External Inhibition during inhibition: Disinhibition.

Temporary disruption of of an extinction caused by a novel external stimulus (noise, smoke, light) which results in the immediate disruption of extinction and a temporary reinstatement of excitation. The same event following extinctions in a temporary increment in performance.

B. Internal Inhibition:

Internal inhibition of conditioned reflexes: (b) Conditioned inhibition internal inhibition, which was termed experimental extinction. In extinction the positive conditioned stimulus is temporarily transformed into a negative or inhibitory one by the simple method of repeating it several times in succession without reinforcement. In the present lecture we shall consider the second type of internal inhibition, which has also been investigated in some detail.. Internal inhibition of conditioned reflexes: (c)

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C. Latent Inhibition: latent inhibition:

often time called the stimulus pre-exposure effect. Reduced associability of familiar stimuli—

Stage 1 CS 1 alone/zilch

Stage 2 CS1 > UCS

Stage 3 CS1>>CR reduced relative to when no pre-exposure allowed.

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D Kamin Kamin Blocking effect also referred to as overshadowing inhibition.

1) CS1 > Shock CR fear

2) CS1 + CS2 > shock fear

3) test CS2 no fear Blocking is demonstrated when response to CS₂ presentation in Stage 3 is minimal or absent in the "Blocking" group, but strong or present in the "Control" group.

again: The Blocking Effect (e.g., reported by Kamin)

Initial learning about a CS-US contingency can limit ("block") subsequent learning about additional CS's that become redundantly paired with the US

Procedure: Three experimental stages in a Blocking experiment
{"Blocking group"}
    Stage 1: Paired presentations of CS₁ and US (e.g., tone followed by shock)
    Stage 2: Paired presentations of Compound CS [CS₁ and CS₂] with US (e.g., tone + light followed by shock)
    Stage 3: Test response to CS₂ presentation alone (light alone)

Excitation and Inhibition

A1. External Inhibition during excitation

E. Counterconditioning