L6: The content of conditioning

Question 1

Why must experimenters be careful in designing conditioning experiments designed to be purely Pavlovian or instrumental?

Answer 1

The association the animal learns may not be the one the experimenter intends.

Question 2

What are the four types of outcome that can occur when PavlovianxInstrumental design is crossed with Pavlovian/Instrumental learning?

Answer 2

• Pavlovian design, Pavlovian learning (Pure Pavlovian conditioning
• Pavlovian design, “instrumental” learning (Superstition)
• Instrumental design, instrumental learning (pure instrumental conditioning
• Instrumental design, Pavlovian learning (implicit Pavlovian learning)

Question 3

What test can be used to determine if a response is instrumental or Pavlovian?

Answer 3

The omission test can be used.

Question 4

How does the omission test work?

Answer 4

The CR must now prevent the US from occurring. A true instrumental response will extinguish quickly, because it is within the animal’s control. A Pavlovian response will not pass the omission test - the animal will continue producing it reflexively, because it is outside conscious control.`

Question 5

What paradigm is commonly used to demonstrate that a response which appears instrumental can actually be Pavlovian?

Answer 5

Autoshaping in pigeons. Pigeons will learn to peck at a light that predicts food. However, this behaviour fails the omission test, indicating it is a Pavlovian reflex.

Question 6

What feature of conditioned responses allowed the CS-UR theory to persist?

Answer 6

In many cases, the CR is equivalent to the UR. Thus it appears that a simple S-R link between the CS and UR is being formed.

Question 7

List three phenomena that can’t be explained by S-R learning.

Answer 7

• conditioning occurs even when responses are prevented during training
• devaluation of the US affects responding to the CS. Responding depends on value of US at time of testing, not initial training
• mediated conditioning. punishing a CS can reduce responding to the US

Question 8

Why can it be difficult to disentangle S-S and S-R learning?

Answer 8

• A single stimuli can consist of multiple features.
• Conditioning probably happens on multiple levels.

An animal probably acquires multiple S-S connections with regard to several features of a CS, and S-R connection with regard to its behaviour in response to that stimulus

Question 9

Although CR’s are useful indexes of conditioning, what is their limitation?

Answer 9

CR’s don’t indicate the content of what is learnt.

Question 10

Give an example of different CS’ to the same US producing different CR’s.

Answer 10

Rats given shocks will react differently depending on the CS.

• if the CS is diffuse, like a noise, rats will freeze
• if the CS is localised, like a probe, rats will withdraw from it or atttempt to bury it

Question 11

Pigeons peck at visual CS’ like lights, but only show increased general activity with tone CS’. How did Rescorla show the content of conditioning was similar despite these two distinct responses?

Answer 11

• In the initial phase, Rescorla conditioned a light and a tone to food
• the secondary phase, Rescorla carried out secondary conditioning, pairing the light and the tone with two different visual stimuli, X and Y
• Rescorla tested X and Y, and both produced the same amount of pecking

Question 12

How did Rescorla show that a Pavlovian CS can influence instrumental behaviour?

Answer 12

• in the first phase, Rescorla classically conditioned CS1 and CS2 to two different stimuli, US1 and US2.
• the second, instrumental phase, Rescorla trained rats to pull a chain for US1 and press a lever for US2
• in the third phase, Rescorla presented CS’ 1 and 2. CS 1 increased chain pulling, and CS 2 increased lever pressing.