Aphasia overview
Aphasia Microchapters |
Diagnosis |
---|
Treatment |
Case Studies |
Aphasia overview On the Web |
American Roentgen Ray Society Images of Aphasia overview |
Please help WikiDoc by adding more content here. It's easy! Click here to learn about editing.
Overview
Aphasia (or aphemia) is a loss of the ability to produce and/or comprehend language, due to injury to brain areas specialized for these functions. It is not a result of deficits in sensory, intellect, or psychiatric functioning. It is also not due to muscle weakness or a cognitive disorder.
Depending on the area and extent of the damage, someone suffering from aphasia may be able to speak but not write, or vice versa, or display any of a wide variety of other deficiencies in language comprehension and production, such as being able to sing but not speak. Aphasia may co-occur with speech disorders such as dysarthria or apraxia of speech, which also result from brain damage.
Causes
Usually, aphasias are a result of damage (lesions) to the language centres of the brain (like Broca's area). These areas are almost always located in the left hemisphere, and in most people this is where the ability to produce and comprehend language is found. However, in a very small number of people language ability is found in the right hemisphere. In either case, damage to these language areas can be caused by a stroke, traumatic brain injury, or other head injury. Aphasia may also develop slowly, as in the case of a brain tumor or progressively neurological disease. It may also be caused by a sudden hemorrhagic event within the brain.
Risk Factors
Anyone can acquire aphasia, including children, but most people who have aphasia are middle-aged or older. Men and women are equally affected. According to the National Aphasia Association, approximately 80,000 individuals acquire aphasia each year from strokes. About one million people in the United States currently have aphasia.
History and Symptoms
Aphasia can be assessed in a variety of ways, from quick clinical screening at the bedside to several-hour-long batteries of tasks that examine the key components of language and communication.