Dyslexia in adults: Evidence for deficits in non-word reading and in the phonological representation of lexical items

Abstract

Difficulties in reading and language skills which persist from childhood into adult life are the concerns of this article. The aims were twofold: (1) to find measures of adult reading processes that validate adults' retrospective reports of difficulties in learning to read during the school years, and (2) to search for indications of basic deficits in phonological processing that may point toward underlying causes of reading difficulties. Adults who reported a history of difficulties in learning to read (n=102) were distinctly disabled in phonological coding in reading, compared to adults without similar histories (n=56). They were less disabled in the comprehension of written passages, and the comprehension disability was explained by the phonological difficulties. A number of indications were found that adults with poor phonological coding skills in reading (i.e., dyslexia) have basic deficits in phonological representations of spoken words, even when semantic word knowledge, phonemic awareness, educational level, and daily reading habits are taken into account. It is suggested that dyslexics possess less distinct phonological representations of spoken words.

Differences between written and spoken input in learning new words

“…Specific problems in representing phonology have been attributed to dyslexics (Elbro et al, 1994;Elbro & Jensen, 2005;Snowling, et al, 1986). Elbro & Jensen (2005) summarize the argument that dyslexics tend to have underspecified phonological representations, which, for example, leads to the production of non-distinct vowels.…”

Neural plasticity following auditory training in children with learning problems

“…Many children with reading problems exhibit deficits in the perception of speech sounds (de Weirdt, 1988;Elliott et al, 1989;Watson and Miller, 1993). This has been attributed to inadequate phonological awareness skills and/or difficulties in perceiving brief sounds (including rapid spectral changes) which occur in speech (Golden and Steiner, 1969;Godfrey et al, 1981;Lieberman et al, 1985;Werker and Tees, 1987;Liberman et al, 1989;Reed, 1989;Elbro et al, 1994;Torgesen and Barker, 1995;Kraus et al, 1996;Merzenich et al, 1996;Stark and Heinz, 1996;Tallal et al, 1996;Mody et al, 1997;Schulte-Koerne et al, 1999). Of particular importance for some learning-impaired children is that these perceptual deficits can be absent in quiet, but manifested in noise typical of everyday listening situations (Elliot et al, 1979;Brady et al, 1983;Chermak et al, 1989;Cunningham et al, 2001;Bradlow et al, 2003).…”

Screening of phonological awareness in the early elementary grades: an IRT approach

“…Previous research has shown phonological awareness to be strongly related to early reading skills (Bradley & Bryant, 1983;Høien, Lundberg, Stanovich, & Bjaalid, 1995;Liberman, 1973;Perfetti, Beck, Bell, & Hughes, 1987;Wagner & Torgesen, 1987;Wagner, Torgesen, & Rashotte, 1994). There is also evidence that phonological deficits are the critical factor underlying reading problems (Elbro, Nielsen, & Petersen, 1994;Rack, Snowling, & Olson, 1992;Vellutino, Fletcher, Snowling, & Scanlon, 2004). In addition, interventions aimed at the improvement of phonological awareness have been shown to effectively promote learning to read (Lundberg, Frost, & Petersen, 1988;National Institute of Child Health and Human Development, 2000).…”