SAN DIEGO COUNTY, Calif. — A major Hollywood bombshell was dropped Wednesday: action star Bruce Willis is stepping away from his acting career.
His family made the announcement, saying he's suffering from aphasia, a brain condition that essentially steals a person's ability to communicate.
An estimated two million Americans suffer from aphasia: a condition that impacts a person's ability to speak, write and understand language.
Aphasia stems from damage to parts of the brain responsible for language functions.
"It could be something that is acute, like a stroke," said Dr. Irene Litvan, professor of neurology and director of the Parkinson & Other Movement Disorder Center at UC San Diego. "It could be a neurodegenerative disease that is progressive,"
Strokes resulting in brain damage are the most common cause.
Dr Litvan said it could also be caused, for example, by a head injury or a brain tumor. Willis' family has not shared any specific details of his condition.
How aphasia develops in a person depends on the individual.
In the case of a stroke, there is the possibility of some improvement, due to brain plasticity.
"But if it is neurodegenerative, it progresses," Dr. Litvan told CBS 8. "And it can progress to a point that someone can not communicate at all,"
While there is no cure, speech therapy is often used to help patients.
"It depends again on the type of lesion as to how you are can try to improve the language," said Dr. Litvan.
While the effects of aphasia can be extremely difficult for the patient and their family, some progress is being made in research to understand the causes of neurodegenerative diseases.
"We're trying to search for multiple ways, multiple approaches in which we can slow the disease progression," said Dr. Litvan. "So in that regard, yes, I am very hopeful."
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