Aphasia and strokes are two different medical conditions that occur in the brain. Aphasia is a disorder in which a person has trouble expressing and understanding language, and a stroke is a condition in which blood supply to the brain is cut off. When a stroke causes damage to parts of the brain responsible for language, it affects a person’s ability to communicate. The connection between aphasia and strokes, then, is that strokes cause aphasia.
There are two main types of strokes: hemorrhagic and ischemic. During a hemorrhagic stroke, a blood vessel in the brain bursts, causing blood to spill into the brain. In an ischemic stroke, a blood clot travels to or forms in a blood vessel, blocking the travel of blood. As a result of either a burst or blocked blood vessel, the brain’s flow of blood and oxygen stops; this causes brain cells to die in the area where the stroke occurred. Most people who experience a stroke sustain permanent damage from losing these brain cells.
If a stroke occurs near parts of the brain that a person uses for language, it can cause damage to this function, thereby resulting in aphasia. Depending on which language area of the brain suffers damage, a person can develop expressive aphasia, receptive aphasia or global aphasia. Expressive aphasia is when a person has difficulty expressing himself using words and sentences. Receptive aphasia is when a person struggles to understand what others are saying. Global aphasia is when a person suffers from both expressing himself and understanding others.
It is important to understand that although aphasia and strokes are connected, not all strokes cause aphasia and not all cases of aphasia occur as a result of strokes. In other words, the connection between aphasia and strokes is not exclusive. Since a stroke can occur anywhere in the brain, it can cause a wide array of other problems, meaning a person who has stroke will not necessarily develop aphasia. For example, a person who suffers a stroke might instead sustain memory loss, muscle weakness or paralysis.
Though a stroke is the most common cause of aphasia, brain damage can occur from a variety of other medical conditions or events. Blunt trauma, for example, can damage a part of the brain used for language. Any condition that damages language parts of the brain, then, can also cause of aphasia. In addition to this, aphasia can develop gradually as a result of brain cell degeneration.