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Definition: aphasia from The Columbia Encyclopedia

(Әfā'zhӘ), language disturbance caused by a lesion of the brain, making an individual partially or totally impaired in his ability to speak, write, or comprehend the meaning of spoken or written words. It is distinguished from functional disorders such as stammering or stuttering, and from impaired speech due to physical defects in the organs used for speaking. Treatment consists of reeducation; the oral and lip-reading methods employed in the education of deaf and mute children have been found to be of assistance in therapy.

Summary Article: Aphasia
from Encyclopedia of Special Education: A Reference for the Education of Children, Adolescents, and Adults with Disabilities and Other Exceptional Individuals

Everyone with the diagnosis of aphasia has an acquired language disorder, but the type of language disorder (problems understanding talking, problems talking, problems reading, problems writing) and the severity of these difficulties vary, reflecting the different locations and the extent of the damage to the brain. For most people, damage to the left side (hemisphere) is responsible for the aphasia. Aphasia usually has a sudden onset such as a result from a brain injury or stroke, but some individuals have a slower onset as with the development of a brain tumor (NIDCD,).

There also are similarities in the type of problems using language among persons whose brains have been damaged in the same location. Aphasiologists are persons who study aphasia and attempt to provide a structure for understanding and diagnosing this language disorder upon the basis of these variations and similarities. As a result of their studies, there are many different definitions of aphasia and many different classification systems offering a means of subdividing aphasia (Chapey,; Davis,).

Literature within the past decade reflects a general agreement on the following: The term aphasia (acquired language disorder due to brain damage) applies to persons who formerly had intact, developed language functioning and, therefore, the term aphasia does not apply to language disorders experienced by children (Davis,). Some aphasiologists (Darley,; Schuell,) set forth arguments against subdividing or classifying aphasia according to differences or similarities of symptoms. In the opinion of these experts, the variations in symptoms reflect degrees of problems in the total, integrated brain function.

However, if classification is considered, one common basis is nonfluent versus fluent. In this case, separation is made on the basis of whether the symptoms of a person’s language disorder result in a disruption of fluency (Hegde,). (Rosenbek, Wertz, and LaPointe) define being fluent as producing five or more connected words. Obviously, persons who have aphasia and who cannot produce five or more connected words have nonfluent aphasia. Further common subdivision types within nonfluent aphasia include Broca’s, global, isolation, and transcortical motor. Subdivisions of fluent aphasia include Wernicke’s transcortical sensory and conduction.

Other common perspectives seen in the literature for defining symptoms of aphasia are those in terms of cognitive impairments (Chapey,; Davis,) and linguistic analysis of the disordered language (Caplan,; Jakobsen,). Cognitive definitions of aphasia are based on the idea that cognition underlies language and that if language is impaired, some aspects of cognition also must be impaired. Descriptions of symptoms are reported as impairments in long- and short-term memory for words, phrases, and sentences and as impairments in processing linguistic information (Hegde,). Research done from the linguistic point of view is called “neurolinguistic,” and it analyzes the symptoms from a perspective of whether a patient shows difficulties in linguistic units if they are shorter or longer, simple or complex, active or passive, embedded or unembedded, and so forth (Hegde,).

The types of language disorders encountered by persons with aphasia include difficulties in comprehending spoken language (for example, the patient cannot point to a picture or object named, or the person may not know the meaning of ordinary words) and difficulties in talking (the patient may substitute sounds or words and create new words that do not mean anything to the listener, or the person may omit sounds within words or whole words). Persons with aphasia may struggle to get out any words and speak very little, or they may talk a great deal with ease, but the words and grammar do not have meaning for the listener. Persons with aphasia may also experience difficulties in reading or writing and doing number calculations (Hegde,). In addition, there are often many related disorders that occur from the damage to the overall neurological network, such as motor speech problems or paresis of the oral structure and/or arm and leg.

Over one million people in the United States suffer from aphasia and each day almost 300 new cases occur. Rehabilitation requires commitment and support from professionals and family. In an effort to provide a better understanding of this disorder, a national organization, the National Aphasia Association has been formed (LaPointe,).

National Aphasia Association, 350 Seventh Avenue, Suite 902, New York, NY 10001. Tel.: (800) 922-4622, e-mail:, website:

Related Articles

See also Childhood Aphasia; Developmental Aphasia; Language Disorders

  • Caplan, D. (1991). Agrammatism is a theoretically coherent aphasic category. Brain and Language, 40, 274-281.
  • Chapey, R. (1981). Assessment of language disorders in adults. In Chapey, R. (Ed.), Language intervention strategies in adult aphasia (pp. 31-84). Williams & Wilkins Baltimore MD.
  • Chapey, R. (1994). Language intervention strategies in adult aphasia (3rd ed.). Williams & Wilkins Baltimore MD.
  • Darley, F. (1982). Aphasia. W. B. Saunders Philadelphia PA.
  • Davis, G. (1993). A survey of adult aphasia and related language disorders (2nd ed.). Prentice Hall Englewood Cliffs NJ.
  • Hegde, M. (1994). A coursebook on aphasia and other neurogenic language disorders. Singular San Diego CA.
  • Jakobsen, R. (1971). Two aspects of language and two types of aphasic disturbances. In R. Jakobson; M. Halle (Eds.), Fundamentals of language (2nd ed.). Mouton The Hague Netherlands.
  • LaPointe, L. (1997). Aphasia and related neurogenic language disorders (2nd ed.). Thieme New York NY.
  • National Institute on Deafness and Other Communication Disorders (NIDCD). (2005). Aphasia. Retrieved from
  • Rosenbek, J.; LaPointe, L.; Wertz, R. (1989). Aphasia: A clinical approach. PRO-ED Austin TX.
  • Schuell, H. (1972). The Minnesota Test of Differential Diagnosis of Aphasia. University of Minnesota Press Minneapolis.
  • Sheela Stuart
    Georgia Washington University Washington, DC
    Copyright © 2014 by John Wiley & Sons, Inc. All rights reserved.

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