Aphasia Facts


  • Aphasia, a disturbance in the formulation and comprehension of language, is due to damage to brain tissue areas responsible for language; aphasia may occur suddenly or develop over time, depending on the type and location of brain tissue damage.
  • Strokes are a common cause of aphasia (about 80,000 new Strokes are diagnosed per year).
  • Causes of aphasia are mainly due to Strokes, severe head trauma, brain tumours, and brain infections; however, any brain tissue damage for whatever reason that occurs in the language centres of the brain may cause aphasia.
  • Two broad categories of aphasia are fluent and non-fluent (also termed Broca’s aphasia), but there are subtypes of these categories.
  • Aphasia, especially a subtype, is diagnosed by tests given to people to determine the individual’s ability to communicate and understand, using language skills; speech pathologists and neurologists most frequently diagnose the type of aphasia.
  • Aphasia is mainly treated by speech and language therapy and therapy methods are based on the extent and locale of the brain damage.
  • Aphasia research is ongoing; studies include revealing underlying problems of brain tissue damage, the links between comprehension and expression, rehabilitation methods, drug therapy, speech therapy, and other ways to understand and treat aspects of aphasia.


Aphasia is a disorder that results from damage to portions of the brain that are responsible for language. For most people, these are areas on the left side (hemisphere) of the brain. Aphasia usually occurs suddenly, often as the result of a Stroke or head injury, but it may also develop slowly, as in the case of a brain tumour, an infection, or dementia. The disorder impairs the expression and understanding of language as well as reading and writing. Aphasia may co-occur with speech disorders such as dysarthria or apraxia of speech, which also result from brain damage.

Dysarthria: Speech that is characteristically slurred, slow, and difficult to understand. A person with dysarthria may also have problems controlling the pitch, loudness, rhythm, and voice qualities of his or her speech. Dysarthria is caused by paralysis, weakness, or inability to coordinate the muscles of the mouth and throat. Dysarthria can occur as a developmental disability. It may be a sign of a neuromuscular disorder such as cerebral palsy or Parkinson’s disease. It may also be caused by a Stroke, brain injury, or brain tumour. Treatment of dysarthria includes intensive speech therapy with a focus on oral-motor skill development.

Apraxia of speech: A severe speech disorder characterised by the inability to speak, or a severe struggle to speak clearly. Apraxia of speech occurs when the throat and oral-motor muscles do not or cannot obey commands from the brain, or when the brain cannot reliably send those commands. Children with apraxia can be assisted significantly with intensive speech therapy.

Aphasia Facts medical author: © Charles Patrick Davis, MD, PhD

Reprinted, with permission, from:          http://www.medicinenet.com/aphasia/article.htm

© Stroke Recovery Association NSW 2022