Encyclopedia of Clinical Neuropsychology

2011 Edition
| Editors: Jeffrey S. Kreutzer, John DeLuca, Bruce Caplan


  • Steven Z. Rapcsak
  • Pélagie M. Beeson
Reference work entry
DOI: https://doi.org/10.1007/978-0-387-79948-3_852

Short Description or Definition

The term alexia is applied to acquired disorders of reading produced by neurological injury in individuals with normal premorbid literacy skills. Clinically, patients with alexia have difficulty in recognizing, pronouncing, or comprehending written words. Although alexia can occur in relative isolation, it is more frequently encountered in the context of spoken language dysfunction or aphasia. Most individuals with alexia have concommitant spelling impairment or agraphia, suggesting that reading and spelling rely on shared cognitive representations and neural substrates. Acquired alexia needs to be distinguished from developmental dyslexia reflecting a failure to attain normal reading skills.


Alexia is not a single clinical entity. Instead, there are several distinct forms of alexia characterized by specific combinations of impaired and preserved reading abilities and associated with unique lesion profiles. The three most commonly...

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References and Readings

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Steven Z. Rapcsak
    • 1
  • Pélagie M. Beeson
    • 2
  1. 1.Neurology Service (1-27)Neurology Section, Southern Arizona VA Health Care System, Department of Neurology, University of ArizonaTucsonUSA
  2. 2.Department of Speech, Language, & Hearing SciencesThe University of ArizonaTucsonUSA