Learning disorders with a special emphasis on reading disorders: A review of the past 10 years

Objective: To review the past 10 years of clinical and research reports on learning disorders. Method: The most common and best-researched type of learning disorder is reading disability, which is the focus of this review. A selective review of the literature from Psychological Abstracts and Index Medicus from 1985 to the present was conducted. This review focused on conceptual and methodological issues, current assessment practices, epidemiology, correlates of brain function, biological factors, predictors of reading achievement, core deficits, comorbidity, reading development and instructional approaches, treatment, and outcome. Results: Definitional issues, still unresolved, bedevil the field with the debate between those for and those against discrepancy definitions of reading disabilities, Nevertheless, considerable progress has been made. Phonological processing problems are now considered the main core deficit responsible for reading disabilities, Correlates of brain function and possible genetic factors are noted. Comorbidity with externalizing and internalizing disorders is described, and some theories for the overlap are identified. Studies on the comorbidity with internalizing disorders are lacking. Good assessment practice and promising approaches to remediation are identified. Unless a concurrent disorder is present, the use of medication for the treatment of reading disabilities should be considered experimental. Favorable outcomes are dependent on initial severity and a supportive home and school environment. Conclusions: Much progress has been made in our understanding of learning disabilities, especially in reading disabilities. Resolution of definitional and conceptual issues will greatly assist research into assessment, treatment, and long-term outcome of learning disabilities with and without concurrent psychiatric disorders. Further research into the nature, extent, and correlates of comorbid learning disabilities and their treatment is much needed.