Talk show host and media personality Wendy Williams has been diagnosed with primary progressive aphasia and frontotemporal dementia, her care team announced Thursday.
MORE: Wendy Williams diagnosed with primary progressive aphasia, frontotemporal dementia"The decision to share this news was difficult and made after careful consideration, not only to advocate for understanding and compassion for Wendy, but to raise awareness about aphasia and frontotemporal dementia and support the thousands of others facing similar circumstances," the team stated in a press release.
Williams, 59, whose upcoming Lifetime documentary "Where Is Wendy Williams?" premieres Feb. 24, has been open about her health issues in the past, revealing her experience with Graves' disease, a thyroid condition.
Dementia is an umbrella term that describes "the impaired ability to remember, think or make decisions that interferes with doing everyday activities," according to the Centers for Disease Control and Prevention.
Frontotemporal dementia is caused by degeneration of the frontal and/or temporal lobes of the brain, according to the National Institute of Neurological Disorders and Stroke at the National Institutes of Health. It is the most common form of dementia for people under the age of 60, and there is currently no known cure.
According to the agency, symptoms of frontotemporal dementia, or FTD, can vary from one person to another. Symptoms may include "changes in personality, behavior, and judgment"; primary progressive aphasia, which involves "changes in the ability to communicate" as well as "problems with memory, reasoning, and judgment"; and movement disorders or issues with balance or walking.
"FTD is progressive, meaning symptoms get worse over time," the agency states. "In the early stages, people may have just one type of symptom. As the disease progresses, other symptoms will appear as more parts of the brain are affected. It is difficult to predict how long someone with FTD will live."
Here are five things to know about aphasia.
According to the National Institute on Deafness and Other Communication Disorders, another sub-agency within the National Institutes of Health, aphasia results from damage to the parts of the brain that process language, typically the left side of the brain.
The disorder can make it harder to speak, write, read and comprehend.
In most cases, aphasia comes on suddenly, like after a stroke or a traumatic brain injury, according to the NIH.
If a person has a brain tumor or a progressive neurological disease, aphasia may develop more gradually.
In certain conditions, like frontotemporal dementia, the slow decline of brain cells can lead to progressive syndromes, like aphasias.
While people with aphasia have difficulty communicating, the disorder itself does not affect their intelligence, according to the National Aphasia Association.
"For people with aphasia it is the ability to access ideas and thoughts through language -- not the ideas and thoughts themselves -- that is disrupted," according to the NAA.
MORE: Wendy Williams' niece shares glimpse into the life of her aunt in new docThere are different types of aphasia depending on which area of the brain sustained damage.
In Broca's aphasia, which is caused by damage to the frontal lobe of the brain, a person may be unable to produce words or full sentences despite being able to completely understand speech, according to the NIH.
In Wernicke's aphasia, which is caused by damage to the temporal lobe of the brain, a person may speak in long, often made-up sentences, and may have difficulty understanding speech, the agency states.
According to the NIH, another type, global aphasia, can cause extensive damage across the language portions of the brain, leaving a person potentially unable to both speak and understand.
With conduction aphasia, a person may have difficulty repeating words, even though they understand them, while with anomic aphasia, a person may have difficulty naming objects, even though they know what the object is.
In primary progressive aphagia, which is a gradual loss of overall language ability, a person may slowly lose the ability to speak over time, advancing to severe loss over time.
Some people with aphasia can see improvements even without treatment as their brain recovers, according to the NIH.
For others, speech-language therapy is required to help regain the ability to communicate.
How much of their language abilities a person can recover depends on the cause of the brain injury, the extent of the injury and where in the brain the damage occurred and the person's age and health, according to the NIH.
In addition to speech-language therapy, social activities like book clubs and support groups can also be helpful for treatment, as well as family involvement, according to the NIH.
ABC News' Carson Blackwelder and Katie Kindelan, along with Dr. Constantine E. Kanakis and Dr. Eli Cahan, contributed to this article.