CONNECTIONIST MODELLING
CAT
Has fur
purrs
Likes tuna
CONNECTIONIST MODELLING
ANIMALS
Vertebrates
Amphibians
Fish
Mammals
Birds Reptiles
CAT
Has fur
purrs
Likes tuna
Notion of Cognitive Economy
Animal
Vertebrate
fly
lay eggs
feathered
Robin
Birds
have milk
live young
have hair
Penguin
alive sleeps
reproduces
eats
has a spine
Mammals
Cat
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
Notion of Cognitive Economy
Animal
Vertebrate
fly
lay eggs
feathered
Robin
Birds
have milk
live young
have hair
Penguin
alive sleeps
reproduces
eats
has a spine
Mammals
Cat
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
Bruce and Young (1986):
Information Processing Model
Expression
Analysis
Facial Speech
Analysis
View-Centred
Descriptions
Expression-Independent
Descriptions
Structural
Encoding
Face Recognition Units
Directed Visual
Processing
“Cognitive
System”
Person-Identity Nodes
Name Generation
Burton, Bruce & Johnston, (1991):
Interactive Activation and Competition Model
FRUs
‘tony’
‘paul’
SIUs
‘john’
Singer
politician
British
American
Dead
Alive
President
PM
‘Beetle’
‘bill’
NAMES
Bill Clinton
John Lennon
Paul McCartney
Tony Blair
Burton, Bruce & Johnston, (1991):
Interactive Activation and Competition Model
FRUs
‘tony’
‘paul’
SIUs
‘john’
Singer
politician
British
American
Dead
Alive
President
PM
‘Beetle’
‘bill’
NAMES
Bill Clinton
John Lennon
Tony Blair
++++
+
Paul McCartney
+++
+
+
+
+
Burton, Bruce & Johnston, (1991):
Interactive Activation and Competition Model
PROSOPAGNOSIA
‘tony’
‘paul’
SIUs
‘john’
Singer
politician
British
American
Dead
Alive
President
PM
‘Beetle’
‘bill’
NAMES
Bill Clinton
John Lennon
Tony Blair
++++
+
Paul McCartney
+++
ANOMIA
+
+
+
+
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.