Developmental dissociation between visual and auditory repetition priming:The role of input lexicons

Contrasting theories posit the source of verbal repetition priming in the a ctivation of preexisting memory representations in the input lexicons or, a lternatively, in the formation of new episodic memory traces. The two hypot heses predict different outcomes from the comparison of developmental rates of visual and auditory verbal repetition priming. The activation theory pr edicts a developmental dissociation between the early maturation of auditor y priming and the later maturation of visuo-verbal priming, contingent upon the discrepant acquisition rates of the auditory and visual input lexicons . The episodic theory, instead, does not make such an assumption. We admini stered visual and auditory implicit Stem Completion to 40 reading beginners (first-graders), 40 third-graders and 20 fifth-graders. Consistent with pr evious reports, auditory priming was stable across different age groups. Vi sual priming and a measure of lexicality in reading, instead, showed a para llel developmental increase passing from reading beginners to third-graders and to fifth-graders. In the overall group, visual priming and the measure of lexicality in reading were significantly associated. These data describ e a new developmental dissociation in the memory abilities of normal childr en and provide further support for the hypothesis that repetition priming f or words reflects facilitated access to previously established memory repre sentations.