Representation
• What changes?
• What causes change?
• What is the role of the environment in
impacting change?
HD FS 631
Learning & Cognitive
Development
October 7, 2002
Representation
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Two definitions
Why study representations?
• Internal representations
• Skinner:
– How does the child internally represent
events, words, concepts in order to recall
them?
– E.g., Meltzoff
– If learning can be explained with S-R
sequences?
– Who needs theory of internal representation
• S-R inadequate
• Use of external symbols
– Internal representation needed to explain
why, in some paradigms
– Younger children and rats learn faster than do
older children and college students
– Can the child use two- and three-dimensional
models to guide problem solving?
– DeLoache
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Kendler & Kendler (1959)
Reversal Shift:
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Reversal and Nonreversal Skills
For each condition
Child sees pairs of stimuli; chooses one
Child receives reinforcement for each
correct choice
• Trials continues until child is correct on
100% of several trials
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Child sees pairs of stimuli; chooses 1
Set A: Right answer: gold;
Set B: right answer: white
Older children and college students
achieve 100% accuracy before rats and
younger children
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Reversal Shifts
Pair 2
Pair 1
Non-Reversal Shift
Pair 1
• Set A: Right answer: gold; Right Answer:
small
• Preschoolers and rats achieve 100%
accuracy before older children and college
students
Pair 2
Right
Right
Wrong
Wrong
Set A
Set B
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Non-Reversal Shifts
Pair 1
Pair 2
Pair 1
Explanation:
Younger children use different
representations of the problem
Pair 2
• Which is correct stimulus?
Right
Right
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– Reversal: Four changes
– Non-reversal: two changes
Wrong
Wrong
Set A
• Different systems of representation
– Younger children: iconic
– Older children: internal mediating stimulus
(black, white, small, large)
Set B
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Theories of representation
Dual representations
• Piaget
• Changes in representation
– Changes in representation
– Sensorimotor schemes
– Semiotic and perceptual schemes
– Operations: Concrete; formal
– use object as object and as symbol (map)
• Children resist dual encoding
• Except under “deceit” conditions
• Bruner
– Enactive
– Iconic
– Symbolic
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Representation in Infancy
Application of representations?
• Schemes are generalized components of
actions
• Post: math needs to be linked
• Enactive -> Iconic (Enactive) -> Symbolic
(Iconic)
• E -> I (E) -> S (I)
– Begin in reflexive actions
– Construct schemes: internal representations
of actions for sucking, grasping, looting, etc.
• More recent: infancy research suggests
that children build representations from
what they observe, not just what they do
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Experience Expectant
Synapses?
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Mandler (1992)
• Baillargeon: object permanence
• Starkey -Van Loosman: numerosity
(subitizing)
• Wynn: Addition
• Spelke:
– animate/inanimate distinctions
– causality
• Meltzoff:
– Imitation
– Deferred imitation
– Or do they have innate perceptual
distinctions?
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Preschoolers’ representation
• We need only to grant that infants are
born with a capacity to abstract certain
kinds of information from perceptual
displays that they will process and to
redescribe them into conceptual form
• I have suggested that this process is
operative from at least a few months of
age, which would allow concepts to
develop in tandem with sensorimotor
development, rather than having a later
onset.
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Use of symbols: DeLoache
• Theory of mind
Very young children
• resist using model to stand for full size room
• Unless room magically grows big!
• Resist dual encoding
– Autistic children lack!
• Appearance/Reality Distinction (Flavell)
• Phenomenalism
– If it looks changed--it is changed.
– Red milk is red
– Except for pictures!!??
• Mutual Exclusivity in naming:
Similar to dual encoding
• Intellectual reality
– If I know it’s a sponge, it looks like a sponge
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– Remember Piaget’s class inclusion task:
– one object cannot have two names: flower and18
daisy!
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Errorless Retrieval: DeLoache
Probabilistic Representation
• Few concepts have defining criteria
Percentage of
Errorless Retrievals
100
• More concepts: probabilistic (Wittgenstein)
80
• Family Resemblances (Rosch & Mervis)
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– Cue validity
– Wings and feathers important for birds
Older
Younger
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• Feature that makes it likely that objects is
member depends on frequency
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Analogous
Original
Locations
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Rosch & Mervis
Superordinate, subordinate,
basic
Basic level categories
• Precede superordinate and subordinate
categories
• Superordinate: too much variation within
groups
• Subordinate: too many categories; too
much similarity between groups
• Basic categories
Superordinate
Too much variation
within categories
Basic
Maximum
cue validity
– Similar shape
– similar function
– same motor response
• Basic: cue validity maximized
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Child basic:
Vehicles
Cars
Animals
Subordinate
Too many Ford Dodge
Boeing
categories;
too much similarity
between
Dogs
Cats
Planes
Siamese
Piper
Calico
Collie
Lab
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Scripts
• Ball
• Later: perceptually insignificant but
functionally important (e.g., wick)
relevant
• Correlations among features
(Younger & Cohen: 10-month olds)
• Prototypes: most representative
instances of concepts
– Siqueland: 3-4 month olds habituate to
prototype
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• Nelson; Schank & Abelson
• Scripts are very salient for young
children--more salient than categories!!
• Sequences of events
• Affect reading performance
• Fill in information from scripts
• Correct errors from scripts
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– In the restaurant, Jamie ordered cad for
dinner.
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Young Children’s Concepts
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Older children’s concepts
Concrete: “So this is Columbus.” (Piaget)
Perceptual: whale = fish (Bruner)
Holistic: Mother (Werner & Kaplan)
Thematic: chair is to sit (Vygotsky)
Global: Piaget
• Abstract: Columbus is a city in Ohio
• Conceptual: whale; has no scales, has
mammary glands, bears live young
• Analytic: Mother: one who bears? Or
raises the child?
• Taxonomic: chair is furniture
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