"Die Hard" star Bruce Willis is stepping away from acting following a recent diagnosis of aphasia, a disorder affecting the part of the brain responsible for language.
Willis' ex-wife Demi Moore, current wife Emma Heming Willis and daughters announced his decision in an Instagram post Wednesday, noting that "he has been experiencing some health issues and has recently been diagnosed with aphasia, which is impacting his cognitive abilities."
About 1 million people in the United States have aphasia, and there are nearly 180,000 new diagnoses every year, according to the National Aphasia Association.
Aphasia affects each person differently, depending on the cause and severity. People might not be able to speak or understand what's being said to them, or they might lose the ability to write or read.
For example, some aphasia patients may speak in long and complete sentences that make no sense, full of unnecessary or made-up words, the U.S. National Institutes of Health says. Other patients struggle to get a few words out at a time, or completely lose the ability to communicate.
"A person with aphasia may have difficulty producing words, but their intelligence is intact," the National Aphasia Association said in a post on Willis' announcement. "Their ideas, thoughts and knowledge are still in their head -- it's just communicating those ideas, thoughts and knowledge that is interrupted."
Moore's post did not note the cause or extent of Willis' aphasia.
Most often, aphasia is caused by a stroke, according to the NIH. However, the condition also can be caused by a head injury, a brain tumor or a progressive neurological disease.
Willis, 67, is best known for playing New York City cop John McClane in the five-movie "Die Hard" series. He also performed star turns in such hit movies as "Pulp Fiction," "The Sixth Sense," "Armageddon," "Sin City" and "Unbreakable."
He launched his career as a leading man on the 1980s-era TV show "Moonlighting," playing private detective David Addison opposite Cybill Shepherd.
The U.S. National Institutes of Health has more about aphasia.