Discrimination and Categorization Flashcards
What type of learning does discrimination share important features with?
Classical conditioning
Define discrimination
Telling things apart
Define categorization
Grouping things together
How is discrimination of physical stimuli determined?
Stimulus generalisation
Why does discrimination/generalisation occur in the wild?
Adaptive - identify predator/sexual partner/food/hiding place etc.
Define learning
A continuous process mediated by experience with stimuli and reinforcement
What two features will learning of a correct response be dependent upon?
S+ - the reinforcement of the correct stimulus
S- - to a LESSER degree, the negative outcome of an incorrect response
What is the strength of a response determined by?
Excitation - Inhibition
Who studied pigeon responses to colour stimuli? What were they investigating?
Excitatory stimulus generalisation
Spence
What are extinction conditions?
Nothing is rewarded, leading to a decrease in the previously rewarded behaviour
What does the training phase of a transposition experiment consist of? Eg.?
Eg. Reinforcing one wavelength of colour (grey), ignoring another colour (white) to produce a wavelength curve of most avoidance and most activity .
What does the first test of a transposition experiment consist of?
Interference of activation and inhibition curve causing certain probe stimuli to be more likely to elicit a positive response.
Which curve has the greatest magnitude, activation or inhibition?
Activation
What determines the stimulus most likely to be responded to? What model is this known as?
Greatest difference between activation and inhibition curves
Spence model
What type of stimuli is the Spence model good at predicting outcomes for?
One dimensional stimuli eg. colour or sound
What type of model is the Spence model?
Associationist/Connectionist
What type of model other than associationist may explain discrimination responses?
Cognitive - Making a rule eg. “always choose darker”
Requires higher thinking and not seen in simple experiments
What is peak shift?
If animal is reinforced for responding to S+, maximum response is seen around S+
If animal is negatively reinforced with S-, peak response will no longer be observed at S+ - it will move to avoid S-
Reference a study regarding peak shift
Dougherty and Lewis, 1991 - peak shift in horses
Why does peak shift occur evolutionarily?
Animals “play it safe” - more important to avoid danger than get a reward
This means they may not respond optimally in response to rewards
How may animals discriminating “time” be otherwise explained?
Direct perception of hunger/light/temperature/other environmental cues
Give a study potentially showing chickens are able to anticipate the future and exercise self control
Abeyesinghe et al 2005 - Will only show self control if the jackpot reward was big enough
Discrimination is the bases of categorisation - what physical attributes may be discriminated?
Shape, colour, size etc.
How is categorisation different from discrimination?
Novel stimuli can be inserted which are responded to correctly based on the pre-formed rule of discrimination.
What is a probe test?
A novel, previously unencountered stimulus that tests the animal’s response based on past experiences
What is the associationist theory of categorisation?
Simply generalising physical similarity, with no abstraction.
- Memorise rewarded stimuli individually
- Learn particular common features (exemplar)
- Generalise from central tendency (Prototype)
How does a concept differ from a category?
Requires some level of abstraction - an idea of a class of objects NOT purely based on physical similarity
What are the two types of concept?
Absolute - eg. this is an animal
Relational - simpler- eg. this is bigger, this is smaller
- complex - eg. same/different
What was the name of the parrot with apparent conceptual ability
Alex (Owner Irene Pepperberg)
Give an example of a study of simple relational concepts
Hanggi 2003 Bigger/Smaller in Horses
Give 2 examples of ways more complex relational concepts can be investigated
Same/Different
- Delayed match to sample
- Simultaneous arrays
How has it been suggested that same/different arrays are interpreted?
Entropy
What must be remembered when assigning cognitive models to behaviour?
Hard to rule out simpler processes being responsible for apparently complex learning
