Aphasia is a disorder that affects how you communicate. It can impact your speech, as well as the way you write and understand both spoken and written language.

Aphasia usually happens suddenly after a stroke or a head injury. But it can also come on gradually from a slow-growing brain tumor or a disease that causes progressive, permanent damage (degenerative). The severity of aphasia depends on a number of things, including the cause and the extent of the brain damage.

The main treatment for aphasia involves treating the condition that causes it, as well as speech and language therapy. The person with aphasia relearns and practices language skills and learns to use other ways to communicate. Family members often participate in the process, helping the person communicate.


Aphasia is a symptom 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
  • Have difficulty finding words
  • Not understand other people's conversation
  • Not understand what they read
  • Write sentences that don't make sense

Patterns of aphasia

People with aphasia may have different strengths and weaknesses in their speech patterns. Sometimes these patterns are labeled as different types of aphasia, including:

  • Broca's aphasia
  • Wernicke aphasia
  • Transcortical aphasia
  • Conduction aphasia
  • Mixed aphasia
  • Global aphasia

These patterns describe how well the person can understand what others say. They also describe how easy it is for the person to speak or to correctly repeat what someone else says.

Aphasia may develop slowly over time. When that happens, the aphasia may be labeled with one of these names:

  • Logopenic aphasia
  • Semantic aphasia
  • Agrammatism

Many people with aphasia have patterns of speech difficulty that don't match these types. It may help to consider that each person with aphasia has unique symptoms, strengths and weaknesses rather than trying to label a particular type of aphasia.

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 or a loved one suddenly develop:

  • Difficulty speaking
  • Trouble understanding speech
  • Difficulty with word recall
  • Problems with reading or writing


The most common cause of aphasia is brain damage resulting from a stroke — the blockage or rupture of a blood vessel in the brain. Loss of blood to the brain leads to brain cell death or damage in areas that control language.

Brain damage caused by a severe head injury, a tumor, an infection or a degenerative process also can cause aphasia. In these cases, the aphasia usually occurs with other types of cognitive problems, such as memory problems or confusion.

Primary progressive aphasia is the term used for language difficulty that develops gradually. This is due to the gradual degeneration of brain cells located in the language networks. Sometimes this type of aphasia will progress to a more generalized dementia.

Sometimes temporary episodes of aphasia can occur. These can be due to migraines, seizures or a transient ischemic attack (TIA). A transient ischemic attack (TIA) occurs when blood flow is temporarily blocked to an area of the brain. People who've had a are at an increased risk of having a stroke in the near future.


Aphasia can create numerous quality-of-life problems because communication is so much a part of your life. Communication difficulty may affect your:

  • Job
  • Relationships
  • Day-to-day function

Difficulty expressing wants and needs can result in embarrassment, frustration, isolation and depression. Other problems may occur together, such as more difficulty moving around and problems with memory and thinking.

Jun 11, 2022

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