Poster B83, Tuesday, August 20, 2019, 3:15 – 5:00 pm, Restaurant Hall
The role of outline-shape during orthographic processing in deaf readers: Evidence from ERPs
Eva Gutierrez-Sigut1,2,3,4, Marta Vergara-Martínez2, Manuel Perea2;1University of Essex, 2University of Valencia, 3DCAL, University College London, 4ICN, University College London
Research on orthographic processing has shown that skilled hearing readers can quickly access the abstract representations of the letters within a word. Indeed, word recognition times are not affected by peripheral visual features such as the word’s outline-shape (Lavidor, 2011; Perea & Panadero, 2013). Deaf readers can also process orthographic representations quickly during word recognition (see Gutiérrez-Sigut, Vergara-Martínez, & Perea, 2019, for electrophysiological evidence with the masked priming technique). However, previous behavioural experiments suggest that deaf readers rely to a greater degree on visual information during word recognition and spelling than their hearing counterparts. For instance, in an analysis of spelling errors in deaf readers, Padden (1993) found a high rate of confusions among letters of the same height (t, d, and b) or among letters with descenders (p, q, and g), reflecting attempts to reproduce the outline shape of words (see also Perea, Marcet, & Vergara-Martínez, 2015, for perceptual-visual effects in deaf readers). In addition, Barca et al. (2013) found a larger lexicality effect in adult deaf signers than in hearing non-signers, which they interpreted as reflecting enhanced reliance on whole-word visual processing. In the present experiment, we used ERPs to investigate the time course of the influence of the outline-shape of words during word recognition in a group of congenitally deaf readers and in a group of hearing readers. Participants made lexical decisions to words and pseudowords created by replacing one consonant from a high-frequency word (e.g., violin). For half of the pseudoword targets, an ascender consonant (e.g., l) was replaced by another ascending consonant (consistent-shape pseudoword: e.g., viotin). For the other half, the replacement resulted in an inconsistent-shape pseudoword (e.g. viocin). Behavioural data showed a different pattern of results for deaf and hearing readers. Deaf readers were less accurate responding to consistent-shape pseudowords (viotin) than to real words (violin). However, there were no significant differences between inconsistent-shape pseudowords (viocin) and words. Hearing readers, however, were less accurate responding to either type of pseudoword that to real words. The ERP results also showed different effects for deaf and hearing readers. For deaf readers, inconsistent-shape pseudowords (viocin) elicited larger negativities than words between 290 and 600 ms post target onset. In contrast, ERPs to consistent-shape pseudowords (viotin) did not differ from words. This suggest that the overlap in perceptual-visual features between words and pseudowords (outline-shape) overcomes lexical status. In hearing readers, both types of pseudowords elicited larger negativities than words, but each with a different time-course: the lexicality effect for the inconsistent-shape pseudowords (viocin) peaked earlier and lasted longer (340 and 600 ms) than for the consistent-shape pseudowords (viotin) (450 and 600 ms). Thus, the present ERP findings strongly suggest that deaf readers rely to a greater degree on visual characteristics during word recognition than their hearing counterparts.
Themes: Reading, Signed Language and Gesture
Method: Electrophysiology (MEG/EEG/ECOG)