The most common cause of aphasia is brain damage resulting from a stroke â 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 TIA occurs when blood flow is temporarily blocked to an area of the brain. People who've had a TIA are at an increased risk of having a stroke in the near future.