Proceedings of the Annual Meeting of the Cognitive Science Society

Three principles governing the operation of the lexical pathway in a model of reading single words aloud were applied to the question of learning, as measured by times to initiate correct pronunciations. I. At the lexical level, a target word activates a neighborhood of orthographically similar entries in the lexicon. II. At the phoneme level, the correct phonemes in the phonemic spelling of the word compete with the other active phonemes. III. At the naming level, the pronunciation is composed of a conjunction of phonemes. These principles were tested using the dau from a 4-year-old beginning reader (U) , resulting in a goodness-of-fit R^2 = .44. When a rule pathway using grapheme-phoneme correspondences was added to the lexical pathway, the goodness-of-Ht was comparable (R^2 = .46). When single entries were accessed along the lexical pathway, instead of word neighborhoods, and grapheme-phoneme conespondences were accessed along the rule pathway, as in standard dual-route models, the goodness-of-fit R^ 2 fell to .27. Although the modelfltting supported the importance of neighborhood activation and failed to support the importance of rules. grapheme-phoneme correspondences were overtly used by LT in the initial trials with words and when feedback indicated an errorful pronunciation. Thus, rule application may be relatively slow in normal fluent word naming, but may still play a strategic role in attempts to initially decode letter strings or to correct errors.