ERP effects of masked orthographic neighbour priming in deaf readers

In masked priming studies with hearing readers, neighbouring words (e.g., wine, vine) compete through lateral inhibition. Here, we asked whether lateral inhibition also characterizes visual word recognition in deaf readers and whether the neural signature of this competition is the same as for hearing readers. Only real words have lexical representations that engage in lateral inhibition. Therefore, we compared processing of target words following neighbouring prime words (e.g., wine-VINE) and pseudowords (e.g., bine-VINE). Targets following words elicited larger amplitude N400s and slower lexical decision responses than those following pseudowords, indicating more effortful processing due to lateral inhibition. Although these effects went in the same direction for hearing and deaf readers, the distribution of the N400 effect differed. We associate the more anterior effect in hearing readers with stronger co-activation of, and competition among, phonological representations. Thus, deaf readers use lexical competition to recognize visual words, but it is primarily restricted to orthographic representations.