SHORT ANSWER

Experiments in animal learning often focus on the mechanisms of leaning at different levels. What are the 3 levels? On which level would you place the opponent-process theory? On which level would you place Kandel’s experimental work on Aplysia? 

Behavioural level, neural level, and cellular level. Kandel’s work with Aplysia is on the cellular level. The opponent-process theory would be on the behavioural level.

Experimenter A finds a hungry rat will learn to press a lever to obtain food. Experimenter B finds a thirsty pigeon will learn to peck a key that produces an opportunity to drink water. Are these findings consistent, inconsistent, or irrelevant to the general process approach? Why?

These findings are consistent with the general process approach, as there is learning present in both situations, and the learning is being studied in a “standard” experimental situation.

Can learning happen without causing an immediate change in behavior? What so-called “distinction” does this support?

            Yes, learning may not initially result in a performance change, it may cause “latent learning”, which is the so-called “performance distinction”. Latent learning is learning without reinforcement; for example, a rat learning the pattern of a maze will have a better time learning the maze if they have a reward of food, than if not.

Describe the dual-process theory (not the opponent-process theory) and indicate which of the two pathways becomes less responsive over trials. (Hint: The theory was, in part, inspired by Kandel’s observations about the neural basis of changes in the siphon withdrawal reaction of Aplysia to a repeatedly presented water jet).

The dual-process theory is the theory that there are two separate processes operating at the same time that encourage opposite effects; the S-R system habituation, and the State system (sensitization). The dual-process theory states that if the S-R system is producing more habituation than the State system is producing sensitization, then we are likely to see a drop in responding. If the State system is producing more sensitization than the S-R system is producing habituation, then we will see an increase in responding.

Identify the CS, US, CR, and UR in the autoshaped key-pecking preparation with pigeons. Do pigeons encode whether a CS signals food or water or does it simply think something desirable is about to occur?

CS= the cue light; US= the food; UR= pecking at the food; CR= approaching/pecking the cue light. The pecking behaviour is called “autoshaping”.

          Pigeons do not encode whether a CS signals food or water, it simply encodes the sensory properties of the pleasing US, no matter what it is.

CS-US associations evoke conditioned behaviour. Would this explain why pigeons approach and peck a light that signals grain in the “long box” even though pecking is not required and leads to less food? What purpose does conditioned approach behavior serve in the bird’s natural environment?

-       YES, BECAUSE OF AUTOSHAPING, THE PIGEON FORMS AN ASSOCIATION BETWEEN THE LIGHT AND THE UPCOMING GRAIN. THE LIGHT (CS) STARTS TO PREDICT THE US (GRAIN).

What is the truly random control and how does it differ from the unpaired control procedure?

TRC: when the CS and US are presented independently of each other. Determines whether conditioning occurs due to the temporal or probabilistic between CS and US. Whether the CS provides information about the likelihood of the US.

Unpaired control: CS and US are deliberately presented in such a way that they occur close together in time. Controls sensitization and pseudo-conditioning.

Does the CS always have to be followed by the US within a few seconds for a CR to develop? Compare eye-blink conditioning and conditioned taste aversion to answer this question.

Eye blinking: a NS (tone to light) paired with a puff of air to the eye (US), naturally causes an eye-blink (UR). Over time, the tone or light alone (CS) elicits the blink (CR).

Timing: In this case, timing is critical.

• The CS must be presented shortly before the US—within milliseconds to a few seconds.

• If the US comes too late or too early relative to the CS, conditioning is less effective or may not occur at all.

Conclusion: Eye-blink conditioning requires close temporal contiguity between the CS and US.

Conditioned Taste Aversion (CTA)

• Description: A novel taste (CS) is followed—often hours later—by illness (US), such as nausea, causing a strong aversion to that taste (CR).

• Timing: Here, the CS and US can be separated by several hours, yet conditioning still occurs.

• Why this works:

  • CTA is believed to be evolutionarily adaptive—organisms need to associate a taste with illness that might occur well after eating (e.g., from toxins or spoiled food).

• Conclusion: CTA demonstrates that long delays between CS and US can still produce strong conditioning.

What is the 2 x 2 information matrix? Describe of the information contained in each cell.

CS+/Aversive: this is an excitatory response, as you are preparing to receive an aversive stimulus, and then you get a shock, which would make you afraid and startled.

          CS-/Aversive: this is an inhibitory response, as you are expecting to experience an aversive stimulus (shock), but when you don’t get one you feel relief.

          CS+/Appetitive: this is an excitatory response, as you are expecting food and you get food.

          CS-/Appetitive: this is an inhibitory response, as you are expecting food but you don’t get any.

Explain the conditions under which the US, the CS, and the interstimulus interval determine the nature of the conditioned response. Give one laboratory example for each of these three factors.

For example, in the experiment with the quails in the long/short box, if you have a 1-min interval between the US and the CS, then we see sign tracking whether it’s a long box or a short box. If you have a 20-min interval, the quail will sit and wait, and pace excitedly in the box, but it won’t approach the CS and sign track.

Timberlake’s behaviour systems theory is a laboratory example of this:

            When the ISI is 20mins, the CR is general excitement, but when the ISI is 1-min, the CR is sign-tracking toward the CS. (like above^).

 

What is CS-US relevance (also called CS-US belongingness)?

CS-US relevance is the fact that taste and illness go hand-in-hand. For example, rats were given sweet water and they loved it. But, when rats were given sweet water and then exposed to radiation, the next time the rats were given the option to drink sweet water, they refused (taste aversion).

Similarly, someone who eats a peanut butter and banana sandwich every single day for lunch, and then one day randomly gets food poisoning, they will associate the food poisoning with the peanut butter and banana sandwich and will switch to a new lunch, thanks to the taste aversion.

Describe four procedures that lead to inhibitory conditioning, including the A+, AB- procedure.

      1. A+, AB- procedure: this is the retardation/summation tests, to determine if B is truly inhibitory or not. This is done by pairing B with A either with a US, or no US (retardation), and by introducing a third stimulus C, and pairing it with B (summation). Retardation will result in a CS- that is slow to be transformed into a CS+; and summation will result in B suppressing a CR that might otherwise occur to C, where CB should produce less responses than C.

 

            2. Trace conditioning with a long gap after CS offset until the arrival of the US

            3. Many backward conditioning trials, rather than a few.

            4. Unpaired CS and US: the CS and US are negatively correlated or negatively contingent. When one is present, the other is not.

What is Pavlov’s stimulus substitution model?

The animal treats the CS as a substitute for the US, which produces the CR, but the CR doesn’t always resemble the UR in some way.

What are the 3 stages/phases of a second-order (also called higher-order) conditioning experiment? Include the test stage.

      1. Phase 1: CS-US pairings; the CS is paired with a US to evoke a CR

          2. Phase 2: US Devaluation; the value of the US is reduced (ex. By poisoning the food)

          3. Phase 3: CS alone; the original CS will produce the devalued US, which will evoke a lesser CR (like less salivation to food).

          ^ this occurs in S-S learning, but not in S-R learning; the US has no effect on the CR in S-R learning.

What are the 3 stages/phases of a sensory preconditioning experiment? Include the test stage.

CS1 and CS2 being paired together. Then CS1 being paired with food, will produce the CR of salivation. This type of conditioning will also allow the CS2 to evoke the CR of salivation, even though CS2 was never directly paired with the US.

            For example, CS1 = bell; CS2 = paw rubbing (sensory conditioning); US = food; CR = salivation. If CS2 is paired with CS1 (paw rubbing will lead to bell ringing), then after a few trials, when the dog’s paw is rubbed, it will begin to salivate as it is expecting the bell to ring which produces the US of food.