Lecture 7: Cognitive Science A Necker Cube

 Many phenomena look as though mental representations are what’s important, not the stimuli themselves Your mental representation determines what you ‘see’

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 the nature of concepts How do these things figure in our mental life? What’s the nature of the representation? [

 Vision – not much to work with (from

(Figure 2 from Marr & Nishihara (1978: 274)

(from

 Background: we’ve been assuming the ‘classical’ model of cognitive architecture  The mind works directly with mental symbolic representations of various sorts (phrase-structure trees for syntax, family-resemblance clusters for concepts, etc etc.)  Beginning of the 80’s:  Move cognitive science closer to neuroscience  Mind works with artificial neural networks, not representations

A connectionist model in action (from Stillings et al. (1995))

A connectionist model in action (from Stillings et al. (1995)) Input layer Hidden Layer Output layer

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output

The XOR Function Input 1Input 2Output