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Assessing Dyslexia at Six Year of Age
Published on: May 1, 2020
Naming problems do not reflect a second independent core deficit in dyslexia: double deficits explored
Anniek Vaessen1, Patty Gerretsen, Leo Blomert
1Department of Cognitive Neuroscience, University of Maastricht, Maastricht 6200 MD, The Netherlands. a.vaessen@psychology.unimaas.nl
Journal of Experimental Child Psychology
|March 13, 2009
Summary
The double deficit hypothesis in dyslexia is not supported by this study. Naming speed appears to be primarily a measure of phonological processing speed, not a separate deficit.
Area of Science:
- Cognitive Psychology
- Neuroscience
- Developmental Psychology
Background:
- The double deficit hypothesis proposes two core deficits in dyslexia: phonological and naming speed.
- This hypothesis suggests naming speed deficits are independent of phonological deficits.
Purpose of the Study:
- To investigate the validity of the double deficit hypothesis in a large sample of dyslexic individuals.
- To examine the relationship between phonological processing speed, naming speed, and reading speed.
Main Methods:
- A large sample of well-diagnosed dyslexic individuals participated.
- Data analysis focused on the correlations between naming speed, phonological processing speed, general processing speed, and reading speed.
Main Results:
- Naming speed was significantly correlated only with reading speed.
- Phonological processing speed and naming speed were found to load on the same factor, strongly influencing reading speed.
- General processing speed did not account for the naming speed-reading speed relationship.
Conclusions:
- The findings do not support an independent naming speed deficit in dyslexia.
- Speeded naming tasks primarily reflect phonological processing speed, with an added component of rapid visual-phonological code matching.
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