Pseudohomophone Effects Provide Evidence

Previous research using event-related brain potentials (ERPs) suggested tha t phonological processing in visual word recognition occurs rather la te, typically after seman tic or syntactic processing. Here, we show that phonological activation in visual word recognition can be observed much earlier. Using a lexical d ecision task, we show that ERPs to pseudohomophones (PsHs) (e.g., ROZE) differed from well-matched spelling con tro ls (e.g., ROFE) as ea rly as 150 ms (P150) after stimulus onset. The PsH effect occurred as early as the word frequency effect suggesting that phonological activation occurs early enough to influence lexica l access. Low-resolution electromagnetic tomography analysis (LORETA) revealed that left temporoparietal and right frontotemporal areas are the likely brain regions associated with the processing of phonological information at the lexical level. Altogether, the results show that phonologica l processes are activated early in visual word recognition and play an important role in lexica l access.