Task 4 - Conditioning

Question 1

Name the four basic terms in classical conditioning

Answer 1

US -> Unconditioned stimulus
CS -> Conditioned stimulus
UR -> Natural / Unconditioned response to the US
CR -> Conditioned response

Question 2

Appetitive Conditioning

Answer 2

Conditioning where the US is a positive event

Question 3

Aversive Conditioning

Answer 3

Conditioning where the US is a negative event

Question 4

What are the CS, US, UR and CR in the “eye-blink paradigm”?

Answer 4

CS: Tone
US: Air puff
UR: blinking
CR: Eyeblink (in response to tone)

Question 5

What are conditioned compensatory responses and why do they occur?

Answer 5

• > They are learnt responses in anticipation of a certain stimulus, which will decrease the stimulus’ effect.
• > They occur because our bodies want to maintain homeostasis.

Question 6

What are US-modulatory theories?

Answer 6

Conditioning theories that say that how a stimulus is associated with an US (through conditioning) is determined by the resulting change in how the US is processed

Question 7

What are CS-modulatory theories?

Answer 7

They focus more on the attentional aspect. The way attention is given to different CS’s determines which one of them becomes more associated with the US.

Question 8

Name one popular case for each of the types of modulatory theories.

Answer 8

• US-modulatory: Rescorla-Wagner-Model

- CS- modulatory: Mackintosh’s Limited processing capacity

Question 9

What does Mackintosh say with his theory about “limited processing capacity”?

Answer 9

He says that paying attention to one stimulus will decrease the attention we can give to another one. If we give attention to a certain stimulus is determined by this stimulus’s previous success in predicting the US.

Question 10

Name the core assumptions of the Rescorla-Wagner Model.

Answer 10

• A cue has a certain weight, that predicts the US

- Learning corresponds to an increase in cue weight and a corresponding reduction in prediction error

Question 11

What is a prediction error and what are its consequences?

Answer 11

• > Falsely anticipating the US after experiencing the CS

- > Reduces the cue weight of the CS

Question 12

What are the weaknesses of the Rescorla-Wagner Model?

Answer 12

• Can’t explain latent inhibition
• Can’t describe how attention is modulated during learning
• Doesn’t account for the influence of the Hippocampus

Question 13

What is latent inhibition?

Answer 13

If a cue has been presented without predicting anything for multiple times, learning about a CS-US connection with this particular CS is inhibited
- The Hippocampus is necessary for this.

Question 14

How can the prediction error be calculated mathematically?

Answer 14

Actual US - expected US

Question 15

How can the increase in predictive value / cue weight be calculated mathematically?

Answer 15

Learning rate * prediction error

Question 16

Over multiple learning trials in the Rescorla Wagner Model, how can we estimate the next prediction error?

Answer 16

First prediction error - IPV / increase in cue weight

Question 17

What is the concept of blocking?

Answer 17

Once an association is fully learned, adding another stimulus to the US will not result in this stimulus being used as a predictive CS for the US.
If the second cue however is added during the learning process, learning is accelerated.

Question 18

What is the experiment called, that showed how learning is cut in half if one stimulus of a compound cue is removed?

Answer 18

Kamin’s blocking paradigm

Question 19

What is overshadowing?

Answer 19

When one cue in a compound cue is more salient than the other and takes up more of the cue weight.

Question 20

Explain positive and negative error

Answer 20

Positive: US is stronger than expected -> increase in association
Negative: US is weaker than expected -> decrease in association

Question 21

What is the Cerebellum for when it comes to learning?

Answer 21

It is responsible for learnt / conditioned responses.

Question 22

One folia (fold of the Cerebellum) contains…

Answer 22

• Molecular layer
• Purkinje Layer
• Granular Layer
• White Matter

Question 23

What are key characteristics of the Purkinje Cell?

Answer 23

• 2 dimensional
• connected via parallel mossy fibers and climbing fibers
• Gives the learned output
• Its output is a strong inhibitory pulse to the nucleus interpositus
• the Purkinje cell gets inhibited by CS-input

Question 24

Explain how the Purkinje cell is connected via climbing and mossy fibers

Answer 24

Mossy fibers:

• parallel
• CS comes through here
• small input but many synapses

Climbing Fibers:

• US comes through here
• One climbing Fiber per Purkinje cell
• one climbing Fiber can be connected to up to 3 Purkinje cells

Question 25

How is the nucleus interpositus connected and what is its function?

Answer 25

- Gives inhibitory output to the inferior olives - Gives excitatory output to the corresponding motor areas, resulting in a CR - Is by default inhibited by the Purkinje cells

Question 26

Describe the pathway that a CS in the brain takes

Answer 26

1. Pontine Nucleus (Brainstem) 2. Nucleus Interpositus directly, or Granule Cell 3. Parallel Fibers 4. Purkinje Cell (5. Interpositus Nucleus)

Question 27

Describe the pathway of the US in the brain.

Answer 27

1. Inferior Olives (brainstem) 2. Interpositus Nucleus directly, or Climbing Fibers 3. Purkinje Cell (4. Interpositus Nucleus)

Question 28

The Cerebellum has a ...

Answer 28

somatotopic map

Question 29

How does the sculpturing analogy apply to learning in the Cerebellum?

Answer 29

The climbing fibers convey an error signal to the purkinje cell. The stronger the input from climbing fibers, the more the purkinje cell will get inhibited in the future, through LTD. Since the Purkinje cell inhibits the Nucleus Interpositus, inhibiting the purkinje cell will result in a "double-minus" and thus the Nucleus Interpositus will be less inhibited. -> Learning in the Cerebellum works by carving away unwanted responses at the synapse of climbing Fiber, mossy Fiber and Purkinje cell.

Question 30

How does the LTD process in the Purkinje cell work?

Answer 30

When activated through the parallel fibers, PKC will be produced in the Purkinje cell, which labels the AMPA receptors, that are also active during excitation. When now an US excites the synapse with the climbing Fiber, Calcium flows into the Purkinje cell. This is where LTD happens: Calcium binds with Calmodulin and activates PKC, which will result in AMPA receptors being internalized. Now not only is the number of excitatory receptors decreased, but it is even outnumbered by metabotropic receptors, which hyperpolarize the Purkinje cell, inhibiting it even more.

Question 31

What happens during extinction?

Answer 31

A CR to a CS is shown less frequently due to repeated prediction errors. It has been shown that extinction is more like learning a new connection (CS -> No US) than unlearning the old association (CS -> US)

Question 32

What is the principle of rapid reacquisition?

Answer 32

Even if a response is said to be extinct, it is still relearned more quickly than initial learning of another response.

Question 33

What could be a reason for that so many people overdose in hotel rooms?

Answer 33

The environment you're in when taking a drug can serve as CS for your body to prepare for the intake by releasing hormones that help break down the drug. If this CS is not given (a new environment), the body will not be prepared for the incoming drug.

Question 34

How can latent inhibition be related to addiction?

Answer 34

If a CS has been experienced many times, but without a following intake of the drug, this can lead us to associating the drug and the stimulus more slowly.

Question 35

How can conditioning be used in clinical applications?

Answer 35

Use of placebo - when all the CS's of taking a medicine are given (the environment, the timing, the looks and taste of the medicine, the form of intake etc.), but it is actually a placebo, the body will not know this at first and present the conditioned response.

Question 36

Which effect has activation of the Interpositus on the US-Pathway?

Answer 36

The US-Pathway gets inhibited -> Tolerance

Question 37

What happens, when there is a lesion in the Cerebellum?

Answer 37

- It prevents the acquisition of new conditioned responses and abolishes previously learned ones

Question 38

The Interpositus by default inhibits the inferior olives (US). Why do we still have a strong eye-blink reflex in response to an air-puff?

Answer 38

Because this system in the Cerebellum is only responsible for learned/conditioned responses and not natural responses (UR's).