Bruce Willis poses for rare family photo with Demi Moore, wife Emma Heming and all five children

The world learned Wednesday that Hollywood legend Bruce Willis, 67, was retiring due to his diagnosis of aphasia, a potentially devastating condition that causes a person to lose communication skills.

Willis’s family announced that the condition would take the Die Hard star “away from the career that has meant so much to him.”

About one million Americans have the condition, the National Institutes of Health reports, and about 180,000 people are diagnosed each year.

It can manifest in multiple ways and is often the result of a head injury, stroke, tumor, or other brain impairment.

Aphasia can also be devastating, with experts saying it causes depression in more than a third of cases, can lead to personality changes, and can even drive friends and family away from the affected person.

Other famous examples of aphasia include former Arizona congresswoman Gabby Giffords and Game of Thrones star Emilia Clarke.

‘Imagine being dropped in a country where you don’t speak the language, can’t understand, read, write or speak. It would affect all their interactions – that’s what it’s like to have aphasia,” Darlene Williamson, president of the aphasia association, told DailyMail.com.

While it’s impossible to say for Willis in particular how drastically the condition has affected him and his behavior, Williamson reports that it can often be devastating for patients.

“The consequences of living with a language disability can alter a person’s behavior and outlook on life,” Williamson said.

‘About 35 per cent of people with aphasia experience some depression.’

The cause of the condition, which is often some form of traumatic brain injury or stroke, can lead to massive personality changes.

‘[Aphasia is] difficulty with language that arises from some type of injury to the brain. The most common source is a stroke… but it could come from any other type of damage,” Dr. Brenda Rapp, a cognitive scientist at Johns Hopkins University, told DailyMail.com.

Certain infections that affect the language centers of the brain can also cause the formation of aphasia, along with the cognitive decline and impairment associated with dementia.

The condition can make it very difficult for an actor like Willis to continue his career, as just the process of speaking out loud can become a challenge.

“It would surely be difficult,” Williamson said of trying to continue performing while suffering from the condition.

‘Aphasia affects language comprehension, speech, as well as reading and writing. There are different levels of severity that would be another determining factor. It may not be impossible, but acting would require additional adaptations.

Dr. Rapp said that despite the communication breakdowns caused by the condition, people with the condition still have the same thoughts and are internally the same person. While the experience can be alienating, loved ones must remember that the person has not changed. Pictured: Willis with family and friends after a ‘barbecue’ event in 2018

There are four common types of aphasia that make up the vast majority of cases: fluent, often called Wernicke’s; nonfluent – known as Broca’s; anomic; and Primary Progressive Aphasia.

Rapp explained that there are different forms of the condition because each represents a different type of breakdown in the communication process.

Whether it’s the ability to translate thoughts into appropriate words, the ability to physically say words, or the ability to interpret and understand the speech of others, each part of communication is a complex process and even mild brain damage can cause problems.

While the condition causes communication breakdowns, Rapp points out that the person himself is still the same.

Their thoughts, beliefs, and feelings toward their loved ones remain, even if it can be frustrating and alienating for both the aphasia patient and those around them to deal with the condition.

Willis’s family did not disclose what type he was dealing with, or how severe the case he had, or what root cause was found for the condition.

According to the stroke Association, A UK-based group, Wernicke’s aphasia sufferers have the ability to string together long sentences of words, but often say things in ways that don’t make sense, or even use made-up words.

They will also suffer from reading and writing problems, and may have trouble understanding clear verbal communication to them.

An example used by Rapp is that a person may misinterpret the sentence ‘John kicked the dog’.

Dr. Brenda Rapp, a cognitive scientist at Johns Hopkins University, explains that aphasia is often caused by a stroke and can manifest itself in many different ways.

While the average person would clearly understand who kicked whom in that scenario, a person dealing with this type of condition may have a hard time figuring out if John or the dog was the kicker.

Broca’s aphasia often causes a person to forget words or group an appropriate string of words together, even when their brain can fully understand what they mean.

A person suffering from this type of condition often uses simple and short sentences to communicate, as they are sometimes unable to correctly say what they want.

The Stroke Association says that these sentences will often be around four words or less.

A person suffering from Broca’s aphasia will also have problems with writing, but their reading ability will not be affected.

Someone who suffers from anomic aphasia may struggle to find the specific verbs and nouns they need to get their point across, and will speak very vaguely.

This can also translate into their writing, where they simply won’t be able to generate the correct words needed to say what they would like to say.

Primary Progressive Aphasia Aphasia impairs a person’s ability to communicate in virtually every way.

A person with this version of the condition will have trouble speaking, reading, and writing.

Their ability to process and understand someone who is speaking to them is also impaired.

Doctors can often detect aphasia through an MRI or CT scan, and will be able to identify the exact part of the brain that is causing the problem.

There is no way to completely fix or cure the condition, but patients often undergo speech therapy to help rebuild their language skills.

‘Not much progress [with medication for the condition]…the treatment for aphasia is speech therapy,” Rapp said.

He noted that in some cases, a person may undergo electrical stimulation therapy along with speech therapy to “get the most out of” the experience.

Williamson said that “strong family support is a critical part of living successfully with aphasia.”

However, it is not always permanent, and its duration and severity often depend on the severity of the brain damage.

Stroke victims in particular who suffer from aphasia are able to regain their speech, and often in just a few weeks.