Aphasia - Causes of aphasia

Aphasia is the result of damage to the parts of the brain involved in speaking, reading, writing and understanding others.

Any damage to the language areas of the brain can result in loss of function, leading to aphasia.

The severity of a person's aphasia depends on the location and type of injury sustained by the brain.

Aphasia can occur by itself or alongside other disorders, such as visual difficulties, mobility problems, limb weakness and cognitive changes.

Aphasia affects a person's language, but it doesn't affect a person's intelligence.

Brain damage

Ways the brain can become damaged include:

  • stroke – the brain is deprived of blood and oxygen during a stroke, which leads to death of brain tissue
  • severe head injury – for example, an injury as a result of a road traffic accident or after a serious fall from height
  • brain tumour – where an abnormal growth of cells develops inside the brain
  • health conditions that cause progressive loss of brain cells, such as dementia – Parkinson's disease does not cause aphasia, but some very similar conditions may do so, such as progressive supranuclear palsy (PSP) or corticobasal degeneration (CBD)
  • infections that affect the brain – such as meningitis (an infection of the outer layer of the brain) and encephalitis (an infection of the brain itself), although this is a much rarer cause of aphasia

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