PSYC2002 Study Guide - Final Guide: Eye Tracking, Dishabituation, Ethology
Perceptual Development
Why study perceptual development?
• Perception = INTERPRETATION of sensory input.
• Everyone perceives the world differently.
• Everyone perceives the world differently at different times, eg: day/night.
• Understand how infants and children (on average) experience the world.
• Individual differences.
• Baseline for comparison, eg: Autism.
Theories
Environmental
/Learning
• Stimuli are originally meaningless sensory input.
• Meaning learnt through interactions and building associations.
Ethological
Gibsonian
• Perceptual system is pre-set to learn about the most useful invariant aspects of our
environment.
• 'experience-expectant' learning
o Biologically biased to attend to critical aspects of the environment, eg: faces,
'danger' signals.
o Neural circuitry is rapidly 'tailored' to environmental rapid input during critical or
sensitive periods.
o Neural pruning.
'Experience-
Dependent'
Learning
• Ongoing neural and behavioural plasticity in response to environmental input.
• Occurs outside sensitive periods.
• May be more gradual or subtle.
• Synaptic connections.
Perceptual Narrowing
• Neural architecture is initially 'untuned' (broad) - born with the potential for a greater range of abilities.
• 'Tuned' by environmental input (specific), eg: kittens and line-orientation.
o No need to keep unused abilities.
o Better/more efficient at what we experience most?
• 'Critical' or 'sensitive' period, eg: language.
Neural Development
• Up to 2 yrs old → proliferation of connections between neurons.
o Up to 10,000 per cell.
o Chaotic and inefficient.
o Result in more 'global' experience of input.
o Second wave of proliferation at puberty.
o Pruning from 1yr and 13yrs.
o Mature connections are organised and precise.
Measurement of Perception in Infants
• Challenges
• No language, eg: can't communicate if they like something.
• Must rely on other types of measures - behaviour, neural, psychological, eg: heart rate.
• Meaning inferred.
Behaviour
• Natural looking - eye tracking which parts of an image they're interested in looking at.
• Exploratory behaviour - which different items they'll reach for.
• Facial expressions, eg: positive or negative.
• Vocalisations
• Habituation-dishabituation - can they tell the difference between two stimuli, i.e. are they sensitive to
the difference?
• Preferential looking - do they prefer one stimulus over another? (must be able to tell the difference in
order to show a preference.
Neurological
• fMRI
Vision
• Last sense to develop
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Everyone perceives the world differently at different times, eg: day/night: understand how infants and children (on average) experience the world, baseline for comparison, eg: autism. Stimuli are originally meaningless sensory input: meaning learnt through interactions and building associations. Perceptual system is pre-set to learn about the most useful invariant aspects of our environment. "experience-expectant" learning: biologically biased to attend to critical aspects of the environment, eg: faces, "danger" signals: neural circuitry is rapidly "tailored" to environmental rapid input during critical or sensitive periods, neural pruning. Learning: ongoing neural and behavioural plasticity in response to environmental input, occurs outside sensitive periods, may be more gradual or subtle. Perceptual narrowing: neural architecture is initially "untuned" (broad) - born with the potential for a greater range of abilities. Neural development: up to 2 yrs old proliferation of connections between neurons, up to 10,000 per cell, chaotic and inefficient, result in more "global" experience of input.
