Marie-Line Bosse

Developmental dyslexia: The visual attention span deficit hypothesis

The visual attention (VA) span is defined as the amount of distinct visual elements which can be processed in parallel in a multi-element array. Both recent empirical data and theoretical accounts suggest that a VA span deficit might contribute to developmental dyslexia, independently of a phonological disorder. In this study, this hypothesis was assessed in two large samples of French and British dyslexic children whose performance was compared to that of chronological-age matched control children. Results of the French study show that the VA span capacities account for a substantial amount of unique variance in reading, as do phonological skills. The British study replicates this finding and further reveals that the contribution of the VA span to reading performance remains even after controlling IQ, verbal fluency, vocabulary and single letter identification skills, in addition to phoneme awareness. In both studies, most dyslexic children exhibit a selective phonological or VA span disorder. Overall, these findings support a multi-factorial view of developmental dyslexia. In many cases, developmental reading disorders do not seem to be due to phonological disorders. We propose that a VA span deficit is a likely alternative underlying cognitive deficit in dyslexia.

Phonological and visual processing deficits can dissociate in developmental dyslexia : Evidence from two case studies

The present study describes two Frenchteenagers with developmental reading andwriting impairments whose performance wascompared to that of chronological age andreading age matched non-dyslexic participants.Laurent conforms to the pattern of phonologicaldyslexia: he exhibits a poor performance inpseudo-word reading and spelling, producesphonologically inaccurate misspellings butreads most exception words accurately. Nicolas,in contrast, is poor in reading and spelling ofexception words but is quite good atpseudo-word spelling, suggesting that hesuffers from surface dyslexia and dysgraphia.The two participants were submitted to anextensive battery of metaphonological tasks andto two visual attentional tasks. Laurentdemonstrated poor phonemic awareness skills butgood visual processing abilities, while Nicolasshowed the reverse pattern with severedifficulties in the visual attentional tasksbut good phonemic awareness. The presentresults suggest that a visual attentionaldisorder might be found to be associated withthe pattern of developmental surface dyslexia.The present findings further show thatphonological and visual processing deficits candissociate in developmental dyslexia.

Does visual attention span relate to eye movements during reading and copying

This research investigated whether text reading and copying involve visual attention-processing skills. Children in grades 3 and 5 read and copied the same text. We measured eye movements while reading and the number of gaze lifts (GL) during copying. The children were also administered letter report tasks that constitute an estimation of the number of letters that are processed simultaneously. The tasks were designed to assess visual attention span abilities (VA). The results for both grades revealed that the children who reported more letters, i.e., processed more consonants in parallel, produced fewer rightward fixations during text reading suggesting they could process more letters at each fixation. They also copied more letters per gaze lift from the same text. Furthermore, a regression analysis showed that VA span predicted variations in copying independently of the influence of reading skills. The findings support a role of VA span abilities in the early extraction of orthographic information, for both reading and copying tasks.

La mémorisation de l’orthographe des mots lus en CM2 : effet du traitement visuel simultané

Resume L’acquisition des connaissances orthographiques lexicales est un processus complexe, encore mal compris. Cette acquisition se fait en grande partie de facon implicite au cours de la lecture. Elle dependrait alors de la qualite du decodage et d’autres facteurs restant a preciser. Des donnees theoriques et certains premiers resultats empiriques suggerent que le traitement visuel simultane de toutes les lettres du mot est un facteur important pour l’acquisition de son orthographe specifique. L’etude presentee ici vise a verifier cette hypothese en fin d’ecole primaire et avec differents delais entre lecture du mot et test orthographique. Lors d’une phase de lecture, on manipule la possibilite pour les participants de traiter toutes les lettres des mots simultanement. La reconnaissance de l’orthographe des mots est ensuite evaluee apres un delai de un ou sept jours. Les resultats confirment que la possibilite de prise d’information simultanee du mot entier pendant la lecture favorise la memorisation de son orthographe, quel que soit le delai de restitution.

Audio-visual synchronization in reading while listening to texts: Effects on visual behavior and verbal learning

Reading while listening to texts (RWL) is a promising way to improve the learning benefits provided by a reading experience. In an exploratory study, we investigated the effect of synchronizing the highlighting of words (visual) with their auditory (speech) counterpart during a RWL task. Forty French children from 3rd to 5th grade read short stories in their native language while hearing the story spoken by a narrator. In the non-synchronized (S-) condition the text was written in black on a white background, whereas in the synchronized (S+) RWL, the text was written in grey and the words were dynamically written in black when they were aurally displayed, in a karaoke-like fashion. The children were then unexpectedly tested on their memory for the orthographic form and semantic category of pseudowords that were included in the stories. The effect of synchronizing was null in the orthographic task and negative in the semantic task. Children’s preference was mainly for the S- condition, except for the poorest readers who tended to prefer the S+ condition. In addition, the childrens eye movements were recorded during reading. Gaze was affected by synchronization, with fewer but longer fixations on words, and fewer regressive saccades in the S+ condition compared to the S- condition. Thus, the S+ condition presumably captured the childrens attention toward the currently heard word, which forced the children to be strictly aligned with the oral modality.

Evaluation of Reading Performance of Primary School Children: Objective Measurements vs. Subjective Ratings

We analyze here readings of the same reference text by 116 children. We show that several factors strongly impact subjective rating of fluency, notably number of correct words, repetitions, errors, syllables spelled per minute. We succeeded in predicting four subjective scores – rated between 1 and 4 by human raters – from such objective measurements with a rather high precision (R > .8 for 3 out of 4 scores). This open the way for automatic multidimensional assessment of reading fluency using calibrated texts.

O Papel da Amplitude Visuoatencional e da Consciência Fonêmica na Aprendizagem da Leitura

This study aimed to verify the relationship between visual attention span (VAS), phonemic awareness (PA) and reading performance in a sample of 48 students from the 1st, 3rd and 5th grade from a public elementary school in Sao Paulo. Children were assessed in three sessions through a battery of tasks, which included single word reading, VAS, PA, nonverbal intelligence, phonological memory and letter identification threshold. Results showed that the VAS and PA correlated with performance in reading from 1st to 5th grade, and they play a more important role at 1st grade, but remain relevant in 3rd and 5th grade, especially in the reading of nonwords and irregular words.

Perceptual span, visual span, and visual attention span: Three potential ways to quantify limits on visual processing during reading

ABSTRACT Many lines of evidence have revealed limitations of the human visual system, most notably that only a portion of available information is processed in a single glance. A degree of conceptual confusion has emerged, however, regarding the underlying concepts or mechanisms explaining limited visual processing in reading; perceptual span, visual span, or visual attention span. While the original definitions of these three concepts are clear and well-differentiated, they are routinely used inconsistently in the literature. The primary goal of the present review is to re-specify these three concepts in terms of what they correspond to and how they are determined. Further, we investigate whether these three spans refer to vision-related measurements and/or are based on general cognitive abilities. This review should lead to a better understanding of the involvement of visual functions in reading performance.