Is visual lexical access based on phonological codes? Evidence from a picture-word interference task

The claim that lexical access for visual words is mandatorily mediated by their phonological codes was investigated. Ninety-six subjects performed timed naming responses to pictures while instructed to ignore printed words superimposed on the pictures. Distracter words were either semantically related to the picture label or were homophones of a word semantically related to the picture name. On the basis of the claim that homophones initially activate multiple semantic codes, we hypothesized that the homophone and semantic distracters would yield comparable interference. Picture-word stimulus onset asynchrony (SOA) was varied between subjects as 0 or +100 msec. For an SOA of 0 msec, semantic interference, but no effect from the homophones, was obtained. For an SOA of +100 msec, no effect was obtained in either condition. In combination, these findings indicate a limited role of phonological codes in visual lexical access. It is suggested that the role of phonology in written word identification may vary dependent on procedure and utility to the task.