Phonological processing in visual rhyming: A developmental ERP study

We employed a visual rhyming priming paradigm to characterize the developme nt of brain systems important for phonological processing in reading. We st udied 109 right-handed. native English speakers within eight age groups: 7- 8, 9-10, 11-12, 13-14, 15-16, 17-18, 19-20, and 21-23. Participants decided whether two written words (prime- target) rhymed (JUICE-MOOSE) or not (CHA IR-MOOSE). In similar studies of adults, two main event-related potential ( ERP) effects have been described: a negative slow wave to primes, larger ov er anterior regions of the left hemisphere and hypothesized To index rehear sal of the primes. and a negative deflection to targets, peaking at 400-450 msec, maximal over right temporal-parietal regions, larger for nonrhyming than rhyming targets, and hypothesized to index phonological matching. In t his study these two ERP effects were observed in all age groups; however, t he two effects showed different developmental timecourses. On the one hand, the frontal asymmetry to primes increased with age; moreover, this asymmet ry was correlated with reading and spelling scores, even after controlling for age. On the other hand, the distribution and onset of the more posterio r rhyming effect (RE) were stable across age groups, suggesting that phonol ogical matching relied on similar neural systems across these ages. Behavio rally, both reaction times and accuracy improved with age. These results su ggest that different aspects of phonological processing rely on different n eural systems that have different developmental timecourses.