Dyslexia is a major stressor on children’s personal, emotional and social development and affects about 10% of the school population. Research has revealed a number of problems associated with dyslexia in children, but little follow up into adolescence has been done on this learning disability. However, we do know that around 25% of the dyslexic population with diagnosed childhood dyslexia will compensate in adolescence to the point that their reading is well within the normal range, at least in alphabetic languages.
The proposed project will examine the cognitive and neurophysiological levels of linguistic sensitivity in a group of Hong Kong Chinese-speaking compensated and uncompensated dyslexic adolescents. The proposed project will thus have four aims: (1) to examine which language-related cognitive tasks are best for distinguishing compensated and uncompensated dyslexic adolescents from normal readers; (2) to investigate the extent to which compensated dyslexics have overcome deficiencies in reading and language-related cognitive processes and what residual difficulties still remain; (3) to examine the extent to which compensated and uncompensated dyslexics exhibit cognitive profiles that are similar or different from their childhood profiles; and (4) to use electrophysiological measures to investigate various cognitive aspects of linguistic processes that underlie both groups.
The project will adopt a multi-dimensional approach that considers reading problems as a manifestation of a complex disorder involving multiple dimensions of cognitive and neurological processing. In phase 1, various cognitive measures associated with reading difficulty will be tested to obtain clear cognitive profiles of all participants. A total of 120 Hong Kong secondary school students will be recruited in three groups: 40 uncompensated dyslexics (UD), 40 compensated dyslexics (CD) and 40 chronological age matched (CA). In Phase II, the 120 students from Phase I (40 per group) will participate in different experiments involving linguistic stimuli and ERP to test the extent to which compensated and uncompensated Chinese adolescent dyslexics show different pre-attentive processes in response to verbal stimuli.
The findings of this project will have significant theoretical and educational implications. In practical terms, understanding compensation could provide important information about variability in adolescent literacy development. In theoretical terms, the results will enhance our understanding of the characteristics of both dyslexic groups in the Chinese-speaking population. Furthermore, the project will identify neurobiological markers of Chinese developmental dyslexia, and potentially further clarify the pathophysiology of this disorder.