Phonological Processes, Confrontational Naming, and Immediate Memory in Dyslexia

Abstract

A group of poor readers classified as dyslexic by age/IQ discrepancy criteria (n = 42) were contrasted with two clinic control groups: 56 adequate-for-age readers with attention deficit disorder (ADD) and 21 poor-for-age readers not meeting the IQ discrepancy criterion (slow/borderline group). The children (33 girls, 86 boys) ranged in age from 7.5 years to 12 years. Variables chosen for study included simple and complex phonological processing, speech rate, continuous naming speed, running memory span, serial memory span, and mental addition. Evidence is presented that the two poor reader groups are distinguishable. Unlike the dyslexic group, the slow/borderline group did not differ from the ADD group on three key measures: simple auditory phonological sensitivity, continuous naming speed, and running memory span. Stepwise regression to predict word list reading level showed that once age and verbal IQ were removed (51% of variance), these three key measures accounted for an additional 22% of the variance (R = 0.86, R2 = 0.73). The single best predictor of word list reading level was nonsense word list reading level, which was explained by the same set of five variables that explained real word reading (R = 0.77, R2 = .60). Severity of attentional problems was not linearly related to reading skill in this clinic sample.

Working memory functioning in developmental dyslexia

“…Dyslexic deficits on phonological updating tasks have previously been reported by Ackerman and Dykman (1993) and Smith-Spark et al (2003), with the latter also finding impairments in performance on an analogue task in the spatial domain. A modified version of the latter test will be presented in this paper and, for the sake of completeness, a phonological analogue, the consonant updating task, was also administered.…”

“…Dyslexic deficits in simple verbal memory span, a task that taps the phonological loop's storage capacity, are reported extensively in the literature (e.g., Ackerman & Dykman, 1993; Cohen, Netley, & Clarke, 1984; Gould & Glencross, 1990; Helland & Asbjørnsen, Working memory and dyslexia 6 2004; Jorm, 1983; Miles, 1993; Palmer, 2000; Roodenrys & Stokes, 2001; Rose, Feldman, Jankowski, & Futterweit, 1999; Smith-Spark, Fisk, Fawcett, & Nicolson, 2003). However, there remain questions over whether the impairments uncovered on working memory tasks are the result of phonological processing difficulties or working memory deficits per se.…”

“…More recently, strong evidence linking the consonant updating task with executive processes has emerged in research using the MRI approach. This has directly implicated both the dorsolateral prefrontal cortex (DLPFC) and the ventrolateral prefrontal cortex (VLPFC) in the consonant updating task (Postle, Berger, Goldstein, Curtis, and D'Esposito, 2001).Dyslexic deficits on phonological updating tasks have previously been reported by Ackerman and Dykman (1993) and Smith-Spark et al (2003), with the latter also finding impairments in performance on an analogue task in the spatial domain. A modified version of the latter test will be presented in this paper and, for the sake of completeness, a phonological analogue, the consonant updating task, was also administered.…”

“…This is a limited capacity temporary storage component controlled by the central executive and able to integrate information from different subsystems, using a multi-dimensional code (although see Loisy & Roulin, 2003). Evidence has begun to emerge that the central executive is fractionable and that its different functions are independent of each other (Baddeley, 1996(Baddeley, , 1998(Baddeley, , 2002 Collette & Van der Linden, 2002; Fisk & Sharp, 2004; Handley, Capon, Copp, & Harper, 2002; Miyake, Friedman, Emerson, Witzki, Howerter, & Wager, 2000; Palladino, Mammarella, & Vecchi, 2003; however, a more radical approach is suggested by Towse & Houston-Price, 2001).Dyslexic deficits in simple verbal memory span, a task that taps the phonological loop's storage capacity, are reported extensively in the literature (e.g., Ackerman & Dykman, 1993; Cohen, Netley, & Clarke, 1984; Gould & Glencross, 1990; Helland & Asbjørnsen, Working memory and dyslexia 6 2004; Jorm, 1983; Miles, 1993; Palmer, 2000; Roodenrys & Stokes, 2001; Rose, Feldman, Jankowski, & Futterweit, 1999; Smith-Spark, Fisk, Fawcett, & Nicolson, 2003). However, there remain questions over whether the impairments uncovered on working memory tasks are the result of phonological processing difficulties or working memory deficits per se.…”

Evaluation of the Double-Deficit Hypothesis in College Students Referred for Learning Difficulties

“…Both VNS and PA independently contribute to both real and nonword decoding (Ackerman & Dykman, 1993;Compton et al, 2001;Wolf et al, 2002) after covarying for IQ. Contributions of PA and VNS are generally similar for real words, although PA appears to be a stronger predictor than VNS for nonwords.…”