A Developmental Neural Model of Visual Word Perception

A neurally pl ausi bl e model of how the process of visually perceiving a letter i n the context of a word is learned, and how such processing Occurs i n adults is proposed. The model consists of a collection of abstract letter feature detector neurons and their interconnections. The model also includes a learning rule that specifies how these interconnections evolve with experience. The interconnec-tions between neurons can be interpreted as representing the spatially redundant , sequentially redundant, and transgraphemic information i n letter string displays. (1977) " Brain-State-in-a-Box " (BSB) neural mechanism is then used to implement the proposed model. The resulting system makes explicit qualitative predictions using both letter recognition accuracy and reaction time as dependent measures. In particular, the model offers an integrated explanation of some experiments involving manipulations of orthographic regularity, masking, case alternations, and experi ence with words. The similarities and differences between the model and models proposed by Adams (1979) and McCl el l and and Rumelhart (1961) are also discussed.