ACQ Vol 11 no 2 2009

Literacy

Dyslexia in secondary school students Evidence from the literature Julie Marinac

Dyslexia, as a reading disability, has been widely studied with consistent evidence being reported regarding underlying deficits, aetiology, and effects. Almost all of this research has focused on the primary school sector where students are still developing literacy skills. Very little research is available to guide those who work with students who have similar deficits in secondary school. This can lead to a situation in which data taken from the developmental population are applied to students who are expected to have mature rather than emerging literacy skills. This report provides an overview of different types of dyslexia and summarises the research relating to dyslexia in secondary school students. It proposes that secondary school and adult populations present with phonological processing (PP) based dyslexia rather than developmental reading impairments, and presents clinical implications for speech pathologists and teachers. Defining dyslexia Dyslexia is defined as a “complex, biologically rooted behavioural condition resulting from an impairment of reading-related processes and manifested in difficulties related to the mastery of reading up to the level of population norms under the conditions of adequate education and a normal developmental environment” (Grigorenko 2001, p. 94). It is a complex disorder, found in children, adolescents and adults, demonstrated by unexpected difficulty in learning to read that is not attributable to general cognitive delay, psychiatric or neurologic disorders, sensory impairment or inadequate instruction (World Federation of Neurology, 1968). Current practices may lead to the use of alternative terminology or a complete avoidance of such “labelling”. For example, reading difficulties or impairment may be used, as the term dyslexia “has often been avoided in educational practice because of its predominant emphasis on within- child causative factors and its perceived effects on social policy” (Reason, Frederickson, Heffernan, Martin, & Woods, 1999, p. 16). From the evidence in the literature, it would

appear that this inexplicable and unexpected failure to achieve age-appropriate literacy skills has not changed over time in nature, occurrence or presentation. What appears to have changed is the social acceptability of the terminology used to describe literacy learning failures, and our understanding of this phenomenon. There is general consensus that dyslexia is a complex syndrome that moves beyond the traditional “reading” to “reading-related processes” (i.e., beyond “reading” to include spelling, and written language), and changes in presentation with age and learning experiences (e.g., Benson, 1994; Blachman, 1997; Grigorenko, Wood, Meyer, & Pauls, 2000; Oakhill & Beard, 1999; Richardson & Weydell, 2003). A further complication to the terminology and definitional debate has been introduced in the 2000 revision of the Diagnostic and Statistical Handbook of Mental Disorders (DSM–IV American Psychiatric Association). This reference text, which provides definitive clinical diagnostic guidance for medical professionals, no longer includes “dyslexia” per se but rather describes two learning disorders that correlate with dyslexia – Reading Disorder (RD, 315.00) and Disorder of Written Expression (DWE, 315.2) (DSM–IV TR, 2000). Under this system, students who experience difficulty in both reading and spelling could be diagnosed as having either co-morbid or sequential disorders. For example, those who have difficulty acquiring age appropriate reading skills before demonstrating delays in written language and/or spelling would be diagnosed as having RD. If the student then demonstrates functional reading abilities but still experiences difficulties in producing age appropriate written work, the diagnosis would become DWE (e.g., sequential disorders). Diagnostic subtypes of dyslexia Notwithstanding these terminological issues, those who work in the field rely on diagnostic subtypes of dyslexia to guide assessment and intervention (Morris et al., 1998). At least three primary subtypes have been reported: 1) “visual” or “visual-perception” (Warnke, 1999), 2) “surface” dyslexia (Castles & Coltheart, 1993), and 3) “deep” or “phonological” dyslexia (Stanovich, Siegel, & Gottardo, 1997). Visual dyslexia The first category involves the letter reversals that suggest the classic dyslexia of “strephosymbolia” (Orton, 1995). Anecdotal evidence regarding the success of therapy (e.g., the introduction of “coloured glasses”, etc.) has been reported, but Evans (1998) suggests that such visual confusion, in isolation, should not even be defined as

Keywords diagnosis

dyslexia evidence based practice phonological awareness reading

impairment secondary school

This article has been peer- reviewed

Julie Marinac

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ACQ Volume 11, Number 2 2009

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