Modelling Early Stages of Word Recognition: Case and the Peripheral Dyslexias

This study investigates the visual representations used in the early stages of word recognition. In particular we look at the role of letter position information and the possible existence of visual units which are larger than single letters. Simulations here are intended to model the early stages of visual word recognition in both normal reading and in cases of peripheral dyslexia. In a feedforward network, letter units are coarse coded for position across words. The model uses separate sets of units to code upper and lower case letters. Exposure to all upper and all lower case words trains the letter units to activate a common set of local phonological units

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