Aphasia is a language impairment caused by damage to the parts of the brain that control language, typically the left half of the brain. Brain damage in adults results most frequently from a stroke or other type of traumatic brain injury.
What are the symptoms of aphasia?
Depending on the lobe of the brain and location of injury, various capabilities will be affected. In general, a lesion to the back of the head causes receptive, or comprehension aphasia (Wernicke’s aphasia), and a lesion to the front of the head causes expressive, or verbal aphasia (Broca’s aphasia). Regardless of degree or site of damage, all individuals with aphasia show expressive involvement. It is important to remember that communication is not limited to verbal expression; neither are its injuries. Deficits may appear in recognition of people, written words, common sounds, or a familiar touch. Ability to write, gesture, and emote can also be affected. Many of these symptoms are also characteristic of patients with Alzheimer’s disease, but Alzheimer’s is a degenerative disease that causes a continual and gradual deterioration in mental function, whereas clients with aphasia generally improve.
What is a stroke?
A stroke, or cerebral vascular accident (CVA), is damage to the brain caused by loss of blood supply to the brain. Known as the most common cause of adult language disturbance, strokes claim 1,300,000 lives annually. Strokes occur as a result of an embolism, thrombosis, or hemorrhage. Specifically, an embolism is a fragment of a blood clot or other foreign particle that travels in the blood vessel until it obstructs blood flow. A thrombosis is a clot that is fixed along the vessel wall, commonly caused by buildup of atherosclerotic plaque. A cerebral hemorrhage results from blood leaking out of the vessels into the cranium. This blood forms a clot and begins to compress and destroy local brain tissue.
Who is at risk for a stroke?
For each decade over the age of 55, the risk of stroke is doubled. Men, especially those who abuse alcohol, drugs, or smoke cigarettes, are 19% more likely to have strokes than women. These risks apply to women as well. The greatest risk factor of stroke is heart disease, high blood pressure, and related diseases such as diabetes. Secondary causes that are suspected but not proven are geographic location, extreme climates and low socioeconomic levels.
What can I expect after a stroke?
Effects of a stroke depend on which blood vessels have been affected by the accident, and whether or not it was a large or small stroke. Large strokes are commonly accompanied by major behavior changes occurring shortly or immediately after the accident and often subsiding almost completely with time. Small strokes, or Transient Ischemic Attacks (TIAs), may not yield any overt behavior changes, but the likelihood of subsequent CVAs increases from one to ten after a single attack.
Two conditions that commonly accompany aphasia are dysarthria and apraxia. These are disorders of the motor planning process required to execute fluent and meaningful speech. Communication is a three-part process. The brain formulates a message and transfers it to the mouth from where it is sent to a listener’s ear. Although the message may make it to the mouth, it requires the motor skills to formulate speech. Dysarthria is a result of paralysis, weakness, or incoordination of the speech musculature. The quality of this speech is typically slow, slurred, and hypernasal, making it very difficult to understand. Apraxia, on the other hand, impairs the voluntary movements needed to execute appropriate musculature for speech. It results in inconsistent initiation, selection, and sequencing of articulatory movements. Sounds and words are understandable, but uniquely combined in a way that leaves the listener unsure of their meaning.
Another prevalent disorder arising after a stroke is dysphagia, or difficulty swallowing. Severity can range from minor weakness in pushing the food back with the tongue, to total loss of the reflexive action which causes the airway to be covered when swallowing. Nutrition is vital to strength and recovery, so dysphagia is an issue that must be immediately addressed.
What can I do to help if someone I know has had a stroke?
The occurrence of a CVA will change everyone it touches, the client, family members, friends, and acquaintances. Possibly the most important thing that family and friends can do for a victim of stroke is be patient and encouraging. From the moment a stroke occurs, everything the client experiences may be different. Imagine not moving, talking, thinking, eating, or feeling the way you did just two days ago. Such changes would devastate anyone. Support from those who love you is vital to the attitude and motivation of recovery. By attending therapy and encouraging hard work towards improvement, loved ones can be an integral part of the rehabilitation process.
How can speech therapy help?
A speech therapist supports clients who have aphasia in all aspects of communication. Speech therapy can help clients learn compensatory strategies for verbal and written communication, practice sounds being produced in error, determine the strongest methods for communication, and support memory functioning.