Aphasia is a sign of some other condition, such as a stroke or a brain tumor.

A person with aphasia may:

  • Speak in short or incomplete sentences
  • Speak in sentences that don't make sense
  • Substitute one word for another or one sound for another
  • Speak unrecognizable words
  • Not understand other people's conversation
  • Write sentences that don't make sense

The severity and scope of the problems depend on the extent of damage and the area of the brain affected.

Types of aphasia

Your doctor may refer to aphasia as nonfluent, fluent or global:

  • Nonfluent aphasia. Damage to the language network near the left frontal area of the brain usually results in Broca aphasia, which is also called nonfluent aphasia. People with this disorder struggle to get words out, speak in very short sentences and omit words. A person might say "Want food" or "Walk park today." A listener can usually understand the meaning.

    People with Broca aphasia may understand what other people say better than they can speak. They're often aware of their difficulty communicating and may get frustrated. People with Broca aphasia may also have right-sided paralysis or weakness.

  • Fluent aphasia. People with this form of aphasia may speak easily and fluently in long, complex sentences that don't make sense or include unrecognizable, incorrect or unnecessary words. They usually don't understand spoken language well and often don't realize that others can't understand them. Also known as Wernicke aphasia, this type of aphasia is the result of damage to the language network in the middle left side of the brain.
  • Global aphasia. Global aphasia results from extensive damage to the brain's language networks. People with global aphasia have severe disabilities with expression and comprehension.

When to see a doctor

Because aphasia is often a sign of a serious problem, such as a stroke, seek emergency medical care if you suddenly develop:

  • Difficulty speaking
  • Trouble understanding speech
  • Difficulty with word recall
  • Problems with reading or writing
March 21, 2015

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