Beyond rhyme or reason: ERPs reveal task-specific activation of orthography on spoken language
Résumé
Metaphonological tasks, such as rhyme judgment, have been the primary tool for the investigation of the effects of orthographic knowledge on spoken language. However, it has been recently argued that the orthography effect in rhyme judgment does not reflect the automatic activation of orthographic codes but rather stems from sophisticated response strategies. Such a claim stands in sharp contrast with recent findings using event-related brain potentials (ERPs) in lexical and semantic tasks, which were taken to suggest that orthographic information occurs early enough to affect the core process of lexical access. Here, we show that the electrophysiological signature of the orthography effect in rhyme judgment is indeed different from the one obtained in online lexical or semantic tasks. That is, we did not find the orthography effect in the 300-350 ms time window which has previously been shown to process lexical information in the lexico-semantic tasks, but the effect appeared within the 175-250 ms and the 375750 ms time-windows which we interpreted to reflect segmentation and decisional process, respectively. We conclude that the interactions between phonology and orthography are task-specific. Metaphonological tasks appear of limited use for studying the core processes and interactions that underlie lexical access. (C) 2010 Elsevier Inc. All rights reserved.