Competitive Dynamics in a Dual-route Connectionist Model of Print-to-sound Transformation

Abstra ct. Thi s pap er describes a connectioni st mod el of prin t-tosound transformation ("word naming" or "reading aloud" ). T he associative network it uses is based on published stu dies of oral reading, and simulat ion res ults are compare d to experiment al data in t he psy chological literature. Th e results ob ta ined are of interest for two separa te reasons. Fir st , the print-to-sound connectionist model is based on an indirectly interactive dual-route hy pothesis of reading aloud. The model confirms t hat this hypothesis, when implemented as a detailed and sizeable compute r simulat ion, can account qualitatively for anumber of behavioral phenomena such as regularity and word frequency effects. The model thu s provides support for a modified dual-route hypothesis involving indirectly inter active routes and verifies the hypothesis' consistency with a set of replicab le psychological data. Th e second reason t he print-to -sound connectioni st model is of interest is t ha t it uses a new approach to implementing compet it ive dynamics in connectionist models. Focused spread of network act ivation and avoidance of network sat uration are produced by using a com petit ive activation mechanism rat her than explicit inhibi tory links between compet ing nodes. T he print -to-sou nd model demonstrates for t he first time t hat competit ive activation mechanisms can funct ion usefully in relatively large, complex situations of interest in cognitive psychology and ar tificial intelligence.