Classical Conditioning Week 2

Question 1

What is Classical conditioning

Answer 1

The procedure of repeatedly pairing an initially neutral stimulus and an unconditioned stimulus (reliably elicits a response)
After conditioning the neutral stimulus becomes
established as a conditioned stimulus with the capacity to elicit a response that usually resembles the unconditioned response.

Question 2

What are the two types of responses that classical conditioning can result in the modification of?

Answer 2

Skeletal responses and autonomic responses

Question 3

What is Pavlov’s stimulus substitution theory?

Answer 3

The theory states that by virtue of repeated pairings between the CS and US, the CS becomes a substitute for the US. So the response initially elicited only by the US is now also elicited by the CS.

Question 4

What are the problems with Pavlov’s stimulus substitution theory?

Answer 4

• The CR is never an exact replica of the UR
• Although many US elicit several different responses as a general rule not all of these are elicited by the CS
• The CR may include responses not part of the UR
• Sometimes the CR and the UR differ substantially

Question 5

According to the behaviour systems theory, What does the US activate?

Answer 5

A behaviour system relevant to that US.

The behaviour that a CS elicits will depend on the physical characteristics of the CS and how it becomes incorporated into the behaviour system activated by the US.

Question 6

What did Pavlov propose in regards to brain regions

Answer 6

There is a specific part of the brain that becomes active whenever a US (e.g. food) is presented (US centre).
Similarly, for every different CS (e.g. tone, light) there is a separate CS centre that becomes active whenever that particular CS is presented.
For every UR (e.g. salivation) there is part of the brain that can be called a response center and it is the activation of this centre that initiates neural commands that ultimately produce the observed response.

Question 7

What learning mechanism is responsible for the CR?

Answer 7

• S-R association: a direct association between the CS centre and the response centre might develop during conditioning
• S-S association: an association between the CS centre and the US centre is formed during conditioning so later, when the CS is presented, the CS center is activated which activates the US center (which in turn activates the response centre)

Question 8

How do you distinguish if the S-S position is correct?

Answer 8

If the S-S position is correct, then after conditioning the occurrence of a CR depends on the continued strength of two associations: the learned association between the CS center and the US center, and the innate association between the US centre and response centre.
Thus, if the US-response connection is somehow weakened, this should cause a reduction in the strength of the CR, since the occurrence of the CR depends on this connection.

Question 9

How do you determine if the S-R position is correct?

Answer 9

If the S-R position is correct, the strength of the CR does not depend on the continued integrity of the US response association but only on the direct association between the CS centre and the response centre.

Question 10

What is US devaluation

Answer 10

The technique of decreasing the effectiveness of the US after an excitatory CS has been created

Question 11

What was the conclusions made by Rescorla in regards to S-R or S-S relationships

Answer 11

He concluded that the strength of the CR is dependent on the continued strength of the US-response association, as predicted by the S-S position but not the S-R position.

Question 12

What is the phenomena of acquisition:

Answer 12

The part of conditioning in which the subject first

experiences a series of CS-US pairings, during which the CR gradually appears and increases in strength.

Question 13

What is Asymptote

Answer 13

The stable maximum level of CR that is gradually approached as conditioning proceeds.

Question 14

What has a major effect on the Asymptote?

Answer 14

The size or intensity of the US

Question 15

What is Extinction

Answer 15

When the CR eventually disappears by repeatedly presenting the CS without the US.

Question 16

What is spontaneous recovery?

Answer 16

Following an acquisition phase on Day 1 and an extinction phase on Day 2, if the animal is returned to
the chamber on Day 3 for another series of extinction trials we are likely to see some CR.

Question 17

What is inhibition theory?

Answer 17

States that after extinction is complete, the subject is left with two counteracting associations:
1- The CS-US association formed during acquisition is the excitatory association (because through this association the CS excites/activates the US centre)
2- A parallel but inhibitory association develops during extinction (so that activity in the CS centre inhibits activity in the US centre)

Upon completion of extinction, the two associations cancel out, so the US centre is no longer activated by presentation of CS.

Question 18

What happens at the end of day two in inhibition theory?

Answer 18

The inhibitory CS-US association is strong enough to counteract completely the excitatory association so no
CR is observed.

Question 19

What happens between Day 2 and Day 3 in inhibition theory?

Answer 19

The inhibitory association is weakened because some time has passed, so at the beginning of Day 3 it can no longer fully counteract the excitatory association, and
some CRs are observed.

Question 20

What would happen with further extinction sessions with inhibition theory?

Answer 20

We might again observe some spontaneous recovery but typically the amount would become smaller until it no longer occurred.

Question 21

What is Disinhibition theory?

Answer 21

Upon completion of an extinction phase (extent
where the CS-bell no longer evokes a CR-salivation):
-if a novel stimulus (buzzer) is presented a few seconds before the bell, then the bell may again come to elicit the CR (salivation).

Question 22

Why did Pavlov call it the disinhibition theory?

Answer 22

Because the fragile inhibition developed during extinction is disrupted by this interfering stimulus (the more stable excitatory association is less affected)…the net result being a slight excitatory tendency.

Question 23

What is rapid reacquisition theory?

Answer 23

Following an acquisition phase and an extinction phase:

-If the subject receives another acquisition phase with the same CS and the same US, the rate of learning is substantially faster during this reacquisition phase.

Question 24

What do spontaneous recovery, disinhibition and rapid reacquisition indicate?

Answer 24

That there is no simple way to unlearn a conditioned response.
Although extinction can cause a CR to disappear, no amount of extinction training can completely wipe out the effects of a classical conditioning experience.

Question 25

What is excitatory conditioning?

Answer 25

Conditioning in which a neutral stimulus is associated with the presentation of a US

Question 26

What is the result of excitatory conditioning?

Answer 26

The CS (now called an excitatory CS or CS+) acquires the capacity to regularly elicit a CR.

Question 27

What is inhibitory conditioning?

Answer 27

Conditioning in which the neutral stimulus is associated with the absence or removal of a US

Question 28

What is the result of inhibitory conditioning?

Answer 28

Conditioning in which the neutral stimulus is associated with the absence or removal of a US

Question 29

What is the prerequisite of inhibitory conditioning

Answer 29

For the absence of a US to be a significant event, the US has to occur periodically in the situation. e.g. signs saying do not enter.
However, these signs provide meaningful information and influence what we do only if they indicate the absence of something we otherwise expect to see.

Question 30

What is the general rule of inhibitory conditioning?

Answer 30

That inhibitory conditioning and inhibitory control of behaviour occur only if there is an excitatory context for the US in question.

Question 31

What was the context that Pavlov provided for his standard inhibitory training procedure that solved the general rule of inhibitory conditioning?

Answer 31

Involved two conditioned stimuli and two kinds of conditioning trials, one for excitatory conditioning and one for inhibitory conditioning:
1. Stimulus A is a buzzer 2. Stimulus B is a light 3.Food is the US 4. Dogs as subjects

Phase One: the sound of the buzzer is repeatedly paired with the presentation of food so the dog eventually shows a stable salivary response to the sound of the buzzer. The buzzer can now be called an excitatory CS or CS+ because it regularly elicits a CR.

Phase Two: the dog receives two types of trials…some like those of phase one (buzzer plus food), but on occasional (random) trials both the buzzer and the light are presented simultaneously but no food is delivered. The simultaneous presentation of two or more CSs is called a compound CS.

Question 32

What are the two ways to interpret the results that Pavlov provided for his standard inhibitory training procedure that solved the general rule of inhibitory conditioning?

Answer 32

1) The light has become a conditioned inhibitor (i.e. its presence causes a reduction in the size of the CR)
2) The animal has learned nothing about the light on its own, and only about the compound CS as a unit