It has been proposed that letters, as opposed to symbols, trigger specialized crowding processes, boosting identification of the first and last letters of words. This hypothesis is based on evidence that single-letter accuracy as a function of within-string position has a W shape (the classic serial position function [SPF] in psycholinguistics) whereas an inverted V shape is obtained when measured with symbols. Our main goal was to test the robustness of the latter result. Our hypothesis was that any letter/symbol difference might result from short-term visual memory processes (due to the partial report [PR] procedures used in SPF studies) rather than from crowding. We therefore removed the involvement of short-term memory by precueing target-item position and compared SPFs with precueing and postcueing. Perimetric complexity was stringently matched between letters and symbols. In postcueing conditions similar to previous studies, we did not reproduce the inverted V shape for symbols: Clear-cut W shapes were observed with an overall smaller accuracy for symbols compared to letters. This letter/symbol difference was dramatically reduced in precueing conditions in keeping with our prediction. Our results are not consistent with the claim that letter strings trigger specialized crowding processes. We argue that PR procedures are not fit to isolate crowding processes.

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In skilled adult readers, reading words is generally assumed to rapidly and automatically activate the phonological code. In adults with dyslexia, despite the main consensus on their phonological processing deficits, little is known about the activation time-course of this code. The present study investigated this issue in both populations. Participants' accuracy and eye-movements were recorded while they performed a visual lexical decision task in which phonological consistency of written words was manipulated. Readers with dyslexia were affected by phonological consistency during second fixation duration of visual word recognition suggesting a late activation of the 2 phonological code. Regarding skilled readers, no influence of phonological consistency was found when the participants were considered as a homogeneous population. However, a different pattern emerged when they were divided into two subgroups according to their phonological and semantic abilities: Those who showed better decoding than semantic skills were affected by phonological consistency at the earliest stage of visual word recognition while those who showed better semantic than decoding skills were not affected by this factor at any processing stage. Overall, the findings suggest that the presence of phonological deficits in readers with dyslexia is associated with a delayed activation of phonological representations during reading. In skilled readers, the contribution of phonology varies with their reading profile, i.e., being phonologically or semantically oriented.

Developmental dyslexia is a specific learning condition characterized by severe and persistent difficulties in written word recognition, decoding and spelling that may impair both text reading fluency and text reading comprehension. Despite this, some adults with dyslexia successfully complete their university studies even though graduating from university involves intensive exposure to long and complex texts. This study examined the cognitive skills underlying both text reading comprehension and text reading fluency (TRF) in a sample of 54 university students with dyslexia and 63 university students without dyslexia, based on a set of tests adapted for an adult population, including listening comprehension, word reading, pseudoword reading (i.e., decoding), phonemic awareness, spelling, visual span, reading span, vocabulary, non-verbal reasoning, and general knowledge. The contribution of these skills to text reading fluency and text reading comprehension was examined using stepwise multiplicative linear regression analyses. As far as TRF is concerned, a regression model including word reading, pseudoword reading and spelling best fits the data, while a regression model including listening comprehension, general knowledge and vocabulary best fits the data obtained for text reading comprehension. Overall, these results are discussed in the light of the current literature on adults with dyslexia and both text reading fluency and text reading comprehension.