Parameter‐based assessment of disturbed and intact components of visual attention in children with developmental dyslexia

Abstract

People with developmental dyslexia (DD) have been shown to be impaired in tasks that require the processing of multiple visual elements in parallel. It has been suggested that this deficit originates from disturbed visual attentional functions. The parameter-based assessment of visual attention based on Bundesen's () theory of visual attention allows one to identify and quantify the underlying deficits. The present study provides the first groupwise comparison between children with DD (n = 12; mean age 9.84 years) and typically developing children (n = 12; mean age 9.87 years) with regard to intact and disturbed components of visual attention. From the performance on whole- and partial-report tasks, we derived individual parameter estimates of four different parameters: visual processing speed, storage capacity of visual short-term memory (VSTM), laterality of attentional weighting and efficiency of top-down control. Groupwise comparisons revealed that general attentional resources, processing speed and VSTM storage capacity, are impaired in children with DD compared to typically developing children. In contrast, selectivity parameters, laterality of attentional selection and attentional top-down control did not differ between these groups. Relating the current findings to previous results, obtained in highly comparable methodological settings, from single cases of children with DD, and from a group of adults with DD, we conclude that slowed perceptual processing speed is a primary visual attentional deficit in DD. Furthermore, reduced VSTM storage capacity seems to modulate the difficulties in written language processing imposed by the disorder.

Do dyslexic individuals present a reduced visual attention span? Evidence from visual recognition tasks of non-verbal multi-character arrays

“…Moreover, in the letters-whole-report task, the dyslexic group identified significantly less letters than the control group. This finding is consistent with previous studies that used this task to detect a VAS deficit (e.g., Bogon et al, 2014;Bosse et al, 2007;Hawelka & Wimmer, 2005;Lobier et al, 2012;Valdois et al, 2003Valdois et al, , 2012. The scores of the two groups on the non-verbal intelligence test and the attention disorder assessment did not differ.…”

“…Most of the supporting evidence for this visual attention span (VAS) deficit has come from studies that examined dyslexic individuals' ability to report on verbal characters (e.g., letters, digits) that are flashed simultaneously for a short duration (Bogon, Finke, Schulte-Körne, Müller, Schneider & Stenneken, 2014;Bosse et al, 2007;Hawelka & Wimmer, 2005;Valdois, Bosse, Ans, Carbonnel, Zorman, David & Pellat, 2003;Valdois, Lassus-Sangosse & Lobier, 2012). In this task, some dyslexic participants have performed worse than controls, particularly when all letters had to be reported (whole-report) compared to a single cued letter (partialreport).…”

Action video games improve reading abilities and visual-to-auditory attentional shifting in English-speaking children with dyslexia

“…Although children and adults with dyslexia can also exhibit visual working memory deficits 51 , working memory is generally found to be impaired in the auditory-phonological domain 5, 6 . Given the proposed visual mechanisms underlying AVG effects, one would predict such training to be more efficient in dyslexic individuals with pronounced deficits in visual attention and perception, with little or no benefit in phonological processing and memory deficits.…”

TVA-based assessment of visual attentional functions in developmental dyslexia

“…A critical methodological challenge is to identify and quantify the impaired function(s). Recently, a number of studies have used a parameter-based account of visual attention assessment ( Dubois et al, 2010 ; Stenneken et al, 2011 ; Lobier et al, 2013 ; Bogon et al, 2014 ). In these studies, the formal framework provided by the “theory of visual attention” (TVA; Bundesen, 1990 , 1998 ) was used to derive quantitative estimates of the individual capabilities of a participant in selecting visual information.…”