Differences in Word Processing Skills of Deaf and Hearing Individuals Reading in Different Orthographies

The study investigated differences in the word processing skills of prelingually deaf and hearing participants reading in five orthographies (Hebrew, Arabic, English, German and Turkish). We tested 256 readers (132 deaf and 124 hearing) from the mid level of education (sixth and seventh grades) using two computerized paradigms that assessed the perceptual and conceptual processing of word pairs. Based on the Orthographic Depth Hypothesis (ODH), we expected those reading in shallow orthographies to process the written words faster and more accurately than those reading in deep orthographies. Moreover, we anticipated a deficit in the word processing skills of deaf readers as compared to their hearing peers, regardless of orthography. Findings suggested that, in orthographies with demanding visuo-perceptual properties, prelingually deaf readers are at risk of developing processing deficits even at the word (lexical) level of text processing. However, such deficits do not seem to be directly related to hearing status or the shallowness of the orthography, but rather seem to reflect the joint contribution of augmented visuo-perceptual processing demands in visually complex orthographies and drastically impoverished reading experience that hampers the optimization of perceptual processes required to efficiently deal with such complexity.