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Reading and Writing

, Volume 15, Issue 1–2, pp 43–72 | Cite as

The second deficit: An investigation of the independence of phonological and naming-speed deficits in developmental dyslexia

  • Maryanne WolfEmail author
  • Alyssa Goldberg O'Rourke
  • Calvin Gidney
  • Maureen Lovett
  • Paul Cirino
  • Robin Morris
Article

Abstract

An increasing body of dyslexia researchdemonstrates, in addition to phonologicaldeficits, a second core deficit in theprocesses underlying naming speed. Thehypothesized independence of phonologicalawareness and naming-speed variables inpredicting variance in three aspects of readingperformance was studied in a group of 144severely-impaired readers in Grades 2 and 3. Stepwise regression analyses were conducted onthese variables, controlling for the effects ofSES, age, and IQ. Results indicated thatphonological measures contribute more of thevariance to those aspects of reading skill thatinvolve decoding or word attack skills;naming-speed measures contribute more to skillsinvolved in word identification. Subtypeclassification findings were equally supportiveof the independence of the two deficits: 19%of the sample had single phonological deficits;15% had single naming-speed deficits; 60% had double-deficits; and 6% could not be classified. The implications of these findingsfor diagnosis and intervention are discussed.

Dyslexia Naming speed Phonology Reading Reading disability 

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Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • Maryanne Wolf
    • 1
    Email author
  • Alyssa Goldberg O'Rourke
    • 2
  • Calvin Gidney
    • 2
  • Maureen Lovett
    • 3
  • Paul Cirino
    • 4
  • Robin Morris
    • 4
  1. 1.Center for Reading and Language Research, Eliot-Pearson Department of Child DevelopmentTufts UniversityMedfordUSA
  2. 2.Tufts UniversityUSA
  3. 3.The Hospital for Slick Children and The University of TorontoCanada
  4. 4.Georgia State UniversityUSA

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