CONNECTIONIST MODELLING

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CONNECTIONIST MODELLING
CAT
Has fur
purrs
Likes tuna
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CONNECTIONIST MODELLING
ANIMALS
Vertebrates
Amphibians Fish Mammals Birds Reptiles
CAT
Has fur
purrs
Likes tuna
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Notion of Cognitive Economy
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Evidence FOR

• Sentence verification speed
• - quicker to verify across fewer levels of
  hierarchy (Schwartz Reisberg,
  1991)

Evidence AGAINST

• Prototypicality effect a robin is a bird a
  penguin is a bird
• Familiarity effect a cat is an animal a cat
  is a mammal

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Notion of Cognitive Economy
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Resolution The Development of Connectionist
Models (Collins Loftus, 1973)

• Abandon hierarchy
• Introduce concept of strong and weak links

Strong familiarity/prototypical exemplars Weak
unfamiliar/non-prototypical exemplars
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Bruce and Young (1986) Information Processing
Model
View-Centred Descriptions
Expression Analysis
Structural Encoding
Expression-Independent Descriptions
Facial Speech Analysis
Face Recognition Units
Directed Visual Processing
Person-Identity Nodes
Cognitive System
Name Generation
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Burton, Bruce Johnston, (1991) Interactive
Activation and Competition Model
FRUs tony paul john bill
SIUs Singer politician British American Dead
Alive President PM Beetle
NAMES Bill Clinton John Lennon Tony Blair Paul
McCartney
9
Burton, Bruce Johnston, (1991) Interactive
Activation and Competition Model
FRUs tony paul john bill
SIUs Singer politician British American Dead
Alive President PM Beetle
NAMES Bill Clinton John Lennon Tony Blair Paul
McCartney
10
Burton, Bruce Johnston, (1991) Interactive
Activation and Competition Model
PROSOPAGNOSIA
tony paul john bill
SIUs Singer politician British American Dead
Alive President PM Beetle
NAMES Bill Clinton John Lennon Tony Blair Paul
McCartney
ANOMIA
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SUMMARY The Value of the Connectionist Approach

• It offers a very powerful model of memory
• It possesses cognitive economy
• It possesses biological plausibility
• It can model both intact memory and impaired
  memory
• It can model simple semantic memory and more
  complex real-world memory
• It provides a model of how information is stored
  and how it is retrieved.