11. Respondant Conditioning PDF

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Summary

Limbic System:Papez (1937): MacLean (1949) The limbic system combines higher mental functions and primitive emotion into one system Located just beneath the cerebrum on both sides of the thalamus, is not only responsible for our emotional lives but also many higher mental functions, Such as learning...

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Limbic System: Papez (1937): MacLean (1949)

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The limbic system combines higher mental functions and primitive emotion into one system

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Located just beneath the cerebrum on both sides of the thalamus, is not only responsible for our emotional lives but also many higher mental functions,

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The primary structures within the limbic system

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Such as learning and formation of memories.

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Amygdala,

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Hippocampus,

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Thalamus,

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Hypothalamus,

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Basal ganglia,

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and Cingulate gyrus

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The limbic system is the reason that some physical things such as eating seem so pleasurable to us,

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and the reason why some medical conditions, such as high blood pressure, are caused by mental stress

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Learning, motivation and emotions are inextricably related

What is Learning: -

A relatively permanent change in behaviour that occurs as a result of experience.

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Nature vs Nurture debate

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but, not drugs, injury/illness, maturation (development)

What is NOT Learning: Nature -> Innate Responses: -

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Reflexes -

Simple, innate response – single set of muscles.

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Patellar, eye-blink reflex.

Taxes. -

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Reflexes involves entire body -

(positive or negative)

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Ex: Moths go to light => Positive photoTaxis cause the whole organism goes to the light

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Positive phototaxis in moths, sea turtles -> go toward the sea.

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Negative phototaxis => Cockroaches run away from light

Instincts (‘Fixed Action Patterns’) -

More complex -> sequence of actions triggered by stimulating a very specific trigger

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E.g. food begging in herring gulls. (Niko Tinbergen) -

Chicks peck a red dot on mom gull’s lower mandible to elicit a sequence of events in which mom gives food

Limitations of Innate Responses: -

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Has to be a physical stimuli (peck on the lower mandible/ hit hammer on knee) -

Stimulus (trigger or ‘releaser’) must be physically present in the environment.

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What about novel stimuli? (has to be physical

Little opportunity to modify response -

Cannot modify the strength of response through trial and error learning

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Modification on an evolutionary (phylogenetic) time scale, not on an individuals (ontogenetic) time scale

Functions of Learning and Memory: Allows for adaptations in behaviour within individual lifetime.

Associative Learning. -

Learning associations between stimuli / events.

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Learning association between actions and stimuli / events.

Non-associative learning. -

Learning that stimuli exist in the world.

Habituation : Eric Kandel

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Learned suppression of a response to a repeated stimulus.

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Rat stats not caring about loud noise if its repeated over and over

Neurological explanation -

Repeated stimulation, the stimulus leads to a decrease in neurotransmitter release into the synapse and onto the motor neuron.

The study of associative learning Pavlovian Conditioning -

Ivan Pavlov, 1922-

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Classical or respondent conditioning in Dogs

Edwin B Twitmeyer, 1873- 1943 -

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First experimental evidence of associative learning in humans -

Hammer to knee => deflect and a tone will play.

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Now if tone is played (no hammer) -> boy showed lil reflexive response (in the beginning)

Association between auditory stimulus and patellar reflex -

Eliciting stimulus not present in environment but associative learning causes psychic relfex

Pavlov’s dogs: Terminology of respondent conditioning -> Classical Conditioning / Respondent Conditioning.

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Unconditioned stimulus (UCS or US): stimulus that has biological relevance

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Unconditioned Response (UCR or UR): Innate response triggered by UCS

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Conditioned stimulus (CS): Neutral stimulus that elicits response through learning

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Conditioned response (CR) – Response produced by CS

Principles of Respondent Conditioning: Studied by Pavlov et al : called themselves the associationists: -

Acquisition when CS-US reinforcement (DVs) (acquisition when tone (post training) -Food reinforcement)

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(bassically changing levels of stimulation of the tone after the association (test the bond)) -

Magnitude of conditioned response. -

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Probability of conditioned response. -

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How many salavatory drops

How probable it is that if u ring the bell from far vs close, u’ll get a response?

Reinforcement of CS by the US. (reinforcement of tone by the food) -

Contiguity -

Pairing in time -

Ring the bell and show the food (while the bell is ringing) -

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Ring bell, wait 2 hours, then show food -

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So if you ring the bell and show the food (in the same area)

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If u ring bell, in the other room, then show food in this room -

You will get strong CS-US association You will get weak CS-US association

Response -

You get a conditioned response (salvation droplets) even before the US is shown

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You get more response as the association is made greeter over time (training = long term)

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You will get weak CS-US association

Pairing in space

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You will get strong CS-US association -> u

Meaning that the CS (the tone) is causing the CR (salvation) Salvation starts the second u hear the bell.

Acquisition when contiguous parings of CS-US. -

Plot the relationship between CS - CR on a graph.

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U get a higher response the more u train

Extinction of CS by the US. (extinction of tone by the food) You break the training by putting bell but no food or food w/o bell -

No reinforcement / loss of contiguity.

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Reponses loses strength.

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Extinction of the CR when reinforcement is removed. -

Not however that its completely gone (not the unlearning)

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Suppressed memories

Spontaneous recovery If u dont do bell with food but just alone -> Sudden salivation again -

Passage of time after extinction

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Retest CS

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Mere passage of time increases likelihood of responses spontaneously returning after extinction.

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Some time, it comes back!

Reacquisition If you suddenly do bell w/ food again -

CS (again) reinforced by CS.

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Savings in relearning -

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Animal has memory trace left, it relearned it easily

Rapid reacquisition when CS-US contiguity (reinforcement) re-established.

Generalisation. -

If u show the animal the exact tone it was trained with -

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High response

If u show a similar tone that it was trained with -

Slightly lower but still high response

Discrimination. If we teach the animal that u get food w/ 3kHz tone but not with 3.5kHz, we see discrimination -

CS+ reinforced.

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CS- non-reinforced.

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Initial generalisation, then the one that's reinforced = high CR Initial generalisation, then the one that's reinforced = lowCR

Relevance of Respondent of Classical Conditioning: -

Extends mechanisms of behavioural adaptation beyond ‘simple’ reflexes

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Ontogenetic adaptation.

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Ubiquitous and preserved.

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All learning is classical conditioning (Pavlov)

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Laws of classical conditioning shape our emotional life.

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associations between stimuli.

Learned Fear: John B Watson - Little Albert. -

John B. Watson was interested in how classical conditioning could be applied to humans

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In 1921, Watson and his research assistant Rosalie Rayner experimented on a 11-month-old infant named Albert

AIM: The goal was to condition Albert to fear a white rat by paring the white rat with a loud bang (UCS) Procedure: Initially, Albert showed no fear of rats, but once the rat was repeatedly paired with the loud noise (UCS), Albert developed a fear of rats. The noise (UCS) induced fear (UCR). After pairings between the loud noise (UCS) and the rat (CS), Albert started to fear the rat. -

Watson’s experiment suggested that classical conditioning could cause some phobias

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The goal was to condition Albert to fear a white rat by paring the white rat with a loud bang (UCS).

Pavlov’s Cortical Model of Learning & Memory: -

Pavlov hypothesised that when the (psychological) connection between the CS and US is conditioned, -

the area of the cortex activated by the CS becomes physically connected with the area activated by the US....