ABSTRACT
Although developmental dyslexia is diagnosed in childhood, follow-up studies indicate that this condition is not specific to childhood but persists into adulthood. According to interview and standardized test data, although many are educationally and occupationally successful, adults with histories of childhood diagnoses of dyslexia continue to exhibit significant reading and spelling disabilities (Bruck, 1985; Finucci, Gottfredson, & Childs, 1986; Labuda & DeFries, 1988; Rawson, 1968). However, little is known about the source or nature of these problems. In the past 10 years, I have conducted several studies on the reading and spelling profiles as well as on the cognitive profiles of adults with childhood histories of dyslexia. These studies are of interest for several reasons. First, on the applied level, the results of these studies provide important information on the prognosis of childhood dyslexia. Second, on a theoretical level, these studies contribute to a unified and extensive account of the basic symptoms and cognitive deficits that underlie developmental dyslexia. Specifically, if the same difficulties that characterize dyslexic children also characterize this population as it reaches adulthood, this indicates that the conceptualization of dyslexia that has been derived from childhood data is developmentally invariant. On the other hand, if dyslexic adults and children show different profiles of difficulties, these data provide a framework for understanding how cognitive profiles may change as a function of experience and development. The data presented in this chapter consistently support the first view—that reading and cognitive profiles of dyslexics remain constant from childhood to adulthood. I argue that phonological processing deficits account for a large proportion of the difficulties encountered by dyslexic children and adults.
