Learning Flashcards
Rescorla-Wagner Model
level of conditioning (classical) is a result of an internal comparison between expected and actual strength of US.
- expectation is based on prior experience with US.
- strength of US is fixed
- Assumes CR gets stronger if the CS-US pair is SURPRISING.
∆V = αβ (λ-V)
∆V – change in associative value of CS (rate of learning)
α – salience of the US to promote conditioning
β – strength of the US to promote conditioning
λ – Magnitude of associative value that can be conditioned for CS; actual CS value (how predictive CS is of US)
V – Current associative value of CS (expectations about the CS-US association/CS value)
- previous models assumed that a CR gets stronger the more a CS is paired with a US
- blocking - neutral stimulus doesn’t change how SURPRSED they are of the CS.
- superconditioning - you are SURPRISED that the US is presented when the neutral is paired with the new excitatory.
Reward variables
- drive
- magnitude
- delay
Pavlovian (classical) conditioning
learning by association
Operant conditioning (Skinner)
learning by reinforcement
Escape learning
- like negative reinforcement
- emit a response that terminates an aversive consequence
Avoidance learning
- can lead to phobias
- emit a response to prevent the occurrence of an aversive consequence altogether
Learned helplessness
- long term effect of repeated exposure to punishment
- believe behaviour has no effect on what happens to them
- immunise by an initial experience of control
prototypical Pavlovian conditioning experiment
.
Shaping
selective reinforcement of behaviour resembling the desired target behaviour in order to reach the target behaviour. (eg. going within 5cm from the lever, touching the lever. so that eventually it will pull the lever)
Skinners thee main categories of reinforcers
primary -
secondary -
generalised -
Reward variables
drive
magnitude
delay
Premack Principle
more probable behaviours will reinforce less probable behaviours (eg. eat broccoli before you can eat favourite food).
Escape learning
- like negative reinforcement
- emit a response that terminates an aversive consequence
Avoidance learning
- can lead to phobias
- emit a response to prevent the occurrence of an aversive consequence altogether
Learned helplessness
- long term effect of repeated exposure to punishment
- believe behaviour has no effect on what happens to them
- immunised by an initial experience of control
punishment limitations
- isn’t as permanent as reinforcement
- reduces trust / increases aggression
How to punish effectively
- no escape
- intense as possible (within reason)
- continuous schedule
- no delay
- over short period of time
- no subsequent reinforcement
Other than schedule, what else can affect conditioning?
- Drive - eg. hungry with food reward is faster then sated.
- Size - may learn faster is reward is bigger
- Delay - immediate reward may be better then delayed reward.
The Three Term Contingency
- discriminative stimulus (sets the occasion)
- operant response (behaviour)
- outcome (reinforcer/punisher) that follows (consequence).
Stages of Classical conditioning
- Habituation (CS alone = UR)
- Acquisition (CS + US = UR)
- Extinction (CS alone = CR)
Two factors that influence the acquisition curve
- intensity of the US
2. order and timing (CS coming before the US is better)
Delay conditioning (short or long)
——————-CS————————
—————US————–
—ISI——-
ISI = interstimulus interval
SHORT has short ISI
LONG has long ISI
- optimal ISI depends in stimulus
Trace conditioning
——–CS—-
——US——–
–trace interval–
(works better then delayed)
Backwards conditioning
- ——-CS————–
- ———–US——
Two types if Pavlovian conditioning
- excitatory conditioning - CS predicts occurrence of US
2. inhibitory conditioning - CS predicts absence of US
Retardation test
- for testing in inhibitory conditioning if the CS is actually successful in predicting the absence of the US.
- after inhibitory conditioning, train an inhibitor and a neutral stimulus to become excitatory
I-US
N-US
and the learning for the Inhibitory stimulus to become an excitatory stimulus will be slower then the new neutral stimulus.
Summation test
- for testing in inhibitory conditioning if the CS is actually successful in predicting the absence of the US.
- after inhibitory conditioning, you present a new excitatory CS alone and also the new excitatory CS+I
- the CR will be higher for the CS alone and lower when they are paired.
Theories about extinction
extinction (CS alone giving decreased CR over time) is not just erasing the association formed in acquisition (CS+US).
1) spontaneous recovery: if you reintroduce the CS after a break, the CR reappears
2) renewal: where extinction is context specific, eg acquisition of phobia etc occurs at home, extinction occurs in therapists office but when you go home the CR reappears.
3) reinstatement: reminder effect where when you present the US alone after extinction, then the CS:CR ??
Habituation
- simplest type of learning
- doesn’t require linking stimuli together
- decline / disappearance of a reflexive response when the same stimulus is repeatedly presented
- eg. infant looking
- ignore unimportant, repetitive events
Hidden assumptions of Classical conditioning
- equipotentiality - any stimulus can be paired with any response DISPROVED BY BLOCKING (can’t form assoc. between neutral stimulus and US)
- contiguity - the more two stimuli are paired, the stronger the individual will associate them DISPROVED BY BLOCKING (control and blocking group exposed same # times - still can’t learn about the neutral stimulus)
- contingency - conditioning changes trial to trial in a regular way
WHAT DOES SUPERCONDITIONING FALSIFY?
blocking
neutral stimulus and excitatory stimulus are paired with the US, you can’t learn anything about the neutral stimulus
superconditioning
neutral stimulus and inhibitory stimulus paired with the US, you form a stronger association between the neutral stimulus and the US.
CS pre-exposure (latent inhibition)
CS pre-exposure retards learning.
conditioning for the CS that was pre-exposed is slower then a new stimulus is.
NOT because of habituation (CS pre-exposure is context specific)
NOT because of conditioned inhibition (failed summation test)
Generalisation and Discrimination in Classical conditioning
Generalisation: child got scared of all fluffy things because it was scared of rats
Discrimination: rabbit eye blink conditioned with shock at certain frequency (was less likely to have CR at other frequencies)
side note: early in acquisition you may have a generalised response to a variety of stimuli but learn to discriminate as learning continues.
Garcia effect
phenomena in classical conditioning where equipotentiality is disproved.
Garcia and Koelling (1966) rats drinking response to sickness VS shock in a light/noise stimuli.
- sickness avoided taste but not light & noise
- shock avoided when light & noise but not taste
Preparedness (Seligman)
dimension on which association between CS and US differ.
prepared associations: faster acquisition and slower extinction
evolutionarily determined
classical fear conditioning
?
classical conditioning and racial attitudes
?
Classical conditioning an Heroine
Siegel et al. (1982)- body’s tolerance to heroine influenced by classical conditioning
ie. similar environmental cues in heroine taking makes endocrine system associate them with heroine and increases tolerance processes.
If completed in different setting, this doesn’t happen and you are more likely to die from OD.
Classical conditioning for phobias
extinguish the CR by presenting the CS without the US. called systematic desensitisation
- construct a FEAR HEIRARCHY
- participants given relaxation training
- psychologist gradually expose client to levels of the hierarchy ad they relax.
Positive Parents Programme (PPP)
teaches parents to use operant conditioning in child rearing
Theories for how reinforcement works (3)
- Skinner: reinforcer increases behaviour and punisher decreases behaviour
- Drive reduction (Hull and Spence): if homeostasis is disrupted, drive is observed to counterbalance. drive reduction of physiological needs = negative reinforcer & major cause for learning. Reinforcers reduce biological drive
- Behaviour regulation (Premack): more probable behaviours reinforce less probable ones.
Habituation (and sensitisation)
‘getting used to something’
allows us to learn that a stimulus is not significant, and therefore you don’t have to be distracted by petty events
Two major ways of learning
- non-associative - habituation (simple)
2. associative - pavlovian (classical) and operant conditioning)
Behaviourism
- measurable effects/ behaviours
- behaviour caused by: goal of organism, environmental demands, internal states
- Black box metaphor, inner working cant be understood
- tabula rascal where you start with a clean slate and learn everything (not nativism)
History
Pavlov - classical conditioning
Watson - behaviourism
Skinner - operant conditioning
Ethology
tabula rasca cannot be true because different species have different genetic predispositions that determine behaviour.
Information processing model
software is to hardware as mind is to brain
Domains of cognitive psychology
cognitive neuroscience perception pattern recognition attention consciousness memory imagery representation of knowledge language cognitive development thinking intelligence comparative psychology evolutionary psychology
Learning
adaptive process where the tendency to perform a specific behaviour, emotion, and/or thought is changed by EXPERIENCE
Changes in behaviour NOT due to associative learning
habituation
innate response tendencies (reflexes, taxes, instincts)
maturation (regular stages, unaffected by practice)
fatigue (disappears after a break)
changes due to physiological/motivation state or evolution
