On the joint effects of stimulus quality, regularity, and lexicality when reading aloud: new challenges

A number of computational models have been developed over the last 2 decades that are remarkably successful at explaining the process of translating print into sound. Nevertheless, 2 of the most successful computational accounts on the table fail to simulate the results from factorial experiments reported in this article in which university students read aloud letter strings that varied in terms of spelling-sound regularity and lexicality (regular words vs. exception words vs. nonwords) and stimulus quality (bright vs. dim). Skilled readers yielded additive effects of regularity and stimulus quality and additive effects of lexicality and stimulus quality on both RT and errors when nonwords were mixed with words. When only words appeared in the list, there was an interaction in which exception words were less affected by low stimulus quality than regular words were; no existing account anticipates or explains these results. We advance a hypothesis that assumes a novel module that accommodates these data and provide an existence proof in the form of a simulation.