Aphasia is a neurological disorder that results from damage to portions of the brain that are responsible for language. For most people, these are parts of 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 tumor. The disorder impairs both 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.
Generally, aphasia can be divided into four broad categories:
- Expressive aphasia involves difficulty in conveying thoughts through speech or writing. The patient knows what he wants to say, but cannot find the words he needs.
- Receptive aphasia involves difficulty understanding spoken or written language. The patient hears the voice or sees the print but cannot make sense of the words.
- Patients with anomic or amnesia aphasia, the least severe form of aphasia, have difficulty in using the correct names for particular objects, people, places, or events.
- Global aphasia results from severe and extensive damage to the language areas of the brain. Patients lose almost all language function, both comprehension and expression. They cannot speak or understand speech, nor can they read or write.
Causes of Aphasia
Aphasia is caused by damage to one or more of the language areas of the brain. Many times, the cause of the brain injury is a stroke. A stroke occurs when, for some reason, blood is unable to reach a part of the brain. Brain cells die when they do not receive their normal supply of blood, which carries oxygen and important nutrients. Other causes of brain injury are severe blows to the head, brain tumors, brain infections, and other conditions of the brain. Individuals with Broca's aphasia have damage to the frontal lobe of the brain. These individuals frequently speak in short, meaningful phrases that are produced with great effort. Broca's aphasia is thus characterized as a nonfluent aphasia. Affected people often omit small words such as "is," "and," and "the." For example, a person with Broca's aphasia may say, "Walk dog" meaning, "I will take the dog for a walk." The same sentence could also mean "You take the dog for a walk," or "The dog walked out of the yard," depending on the circumstances. Individuals with Broca's aphasia are able to understand the speech of others to varying degrees. Because of this, they are often aware of their difficulties and can become easily frustrated by their speaking problems. Individuals with Broca's aphasia often have right-sided weakness or paralysis of the arm and leg because the frontal lobe is also important for body movement.
This left side view of brain shows areas of the brain affected by Broca's and Wernicke's aphasia.In contrast to Broca's aphasia, damage to the temporal lobe may result in a fluent aphasia that is called Wernicke's aphasia. Individuals with Wernicke's aphasia may speak in long sentences that have no meaning, add unnecessary words, and even create new "words." For example, someone with Wernicke's aphasia may say, "You know that smoodle pinkered and that I want to get him round and take care of him like you want before," meaning "The dog needs to go out so I will take him for a walk." Individuals with Wernicke's aphasia usually have great difficulty understanding speech and are therefore often unaware of their mistakes. These individuals usually have no body weakness because their brain injury is not near the parts of the brain that control movement.
Diagnosis of Aphasia
Aphasia is usually first recognized by the physician who treats the individual for his or her brain injury. Frequently this is a neurologist. The physician typically performs tests that require the individual to follow commands, answer questions, name objects, and converse. If the physician suspects aphasia, the individual is often referred to a speech-language pathologist, who performs a comprehensive examination of the person's ability to understand, speak, read, and write.
Treatment of Aphasia
In some instances an individual will completely recover from aphasia without treatment. This type of "spontaneous recovery" usually occurs following a transient ischemic attack (TIA), a kind of stroke in which the blood flow to the brain is temporarily interrupted but quickly restored. In these circumstances, language abilities may return in a few hours or a few days. For most cases of aphasia, however, language recovery is not as quick or as complete.
While many individuals with aphasia also experience a period of partial spontaneous recovery (in which some language abilities return over a period of a few days to a month after the brain injury), some amount of aphasia typically remains. In these instances, speech-language therapy is often helpful. Recovery usually continues over a 2-year period. Most people believe that the most effective treatment begins early in the recovery process.
Some of the factors that influence the amount of improvement include the cause of the brain damage, the area of the brain that was damaged, the extent of the brain injury, and the age and health of the individual. Additional factors include motivation, handedness, and educational level. Aphasia therapy strives to improve an individual's ability to communicate by helping the person to use remaining abilities, to restore language abilities as much as possible, to compensate for language problems, and to learn other methods of communicating.
Treatment may be offered in individual or group settings. Individual therapy focuses on the specific needs of the person. Group therapy offers the opportunity to use new communication skills in a comfortable setting. Family involvement is often a crucial component of aphasia treatment so that family members can learn the best way to communicate with their loved one. Family members are encouraged to:
- Simplify language by using short, uncomplicated sentences.
- Repeat the content words or write down key words to clarify meaning as needed.
- Maintain a natural conversational manner appropriate for an adult.
- Minimize distractions, such as a blaring radio, whenever possible.
- Include the person with aphasia in conversations.
- Ask for and value the opinion of the person with aphasia, especially regarding family matters.
- Encourage any type of communication, whether it is speech, gesture, pointing, or drawing.
- Avoid correcting the individual's speech.
- Allow the individual plenty of time to talk.
- Help the individual become involved outside the home. Seek out support groups such as stroke clubs.
Reference: The National Institute on Deafness & Other Communication Disorders
Last updated May 5, 2017