On the nature of consonant/vowel differences in letter position coding: Evidence from developing and adult readers

In skilled adult readers, transposed‐letter effects (jugde ‐JUDGE ) are greater for consonant than for vowel transpositions. These differences are often attributed to phonological rather than orthographic processing. To examine this issue, we employed a scenario in which phonological involvement varies as a function of reading experience: A masked priming lexical decision task with 50‐ms primes in adult and developing readers. Indeed, masked phonological priming at this prime duration has been consistently reported in adults, but not in developing readers (Davis, Castles, & Iakovidis, 1998). Thus, if consonant/vowel asymmetries in letter position coding with adults are due to phonological influences, transposed‐letter priming should occur for both consonant and vowel transpositions in developing readers. Results with adults (Experiment 1) replicated the usual consonant/vowel asymmetry in transposed‐letter priming. In contrast, no signs of an asymmetry were found with developing readers (Experiments 2–3). However, Experiments 1–3 did not directly test the existence of phonological involvement. To study this question, Experiment 4 manipulated the phonological prime‐target relationship in developing readers. As expected, we found no signs of masked phonological priming. Thus, the present data favour an interpretation of the consonant/vowel dissociation in letter position coding as due to phonological rather than orthographic processing.