In a recent interview, actor Brad Pitt said he has prosopagnosia—a rare neurological condition that is commonly referred to as "face blindness." Writing for the New York Times, Dani Blum details the symptoms, causes, and treatment for the disorder.

Prosopagnosia symptoms

The primary symptom of prosopagnosia is face blindness—not color blindness or general visual impairment, according to Borna Bonakdarpour, a behavioral neurologist at Northwestern Medicine.

The condition is not tied to memory loss, vision impairment, or learning disabilities, according to the National Institute of Neurological Disorders and Stroke. "It is not the same as forgetfulness or sometimes struggling to find the right word," Blum adds.

Individuals' experiences with prosopagnosia will vary in severity. For example, some may have trouble recognizing a familiar face—like a close friend or family member—while others may not be able to recognize their own reflection. In addition, some individuals may not be able to tell the difference between faces and objects.

Notably, some evidence suggests that people who have prosopagnosia may develop chronic anxiety or depression because of the isolation and fear that often accompany the condition.

"Navigating basic social interactions with prosopagnosia can become fraught, and some people avoid contact with family members and other loved ones out of fear that they will not be able to properly recognize or address them," Blum writes.

While Pitt has never received a formal prosopagnosia diagnosis, he said in a recent interview with GQ that he struggled for years to recognize people's faces.

In fact, in a 2013 interview with Esquire, Pitt said his inability to recognize people's faces was so severe that he often wanted to isolate himself as a result. "That's why I stay home," he said.

What causes the condition?

Typically, there are two categories of people that receive a prosopagnosia diagnosis: individuals who are born with the condition, and those who acquire it.

According to Blum, "[r]esearch suggests that congenital, or lifelong, prosopagnosia is less common, although estimates show that as many as one in every 50 people may struggle with some lifelong form of the condition, and scientists theorize that it may run in families."

"There doesn't seem to be any obvious structural abnormality" in the brain for those born with the condition, said Andrey Stojic, director of general neurology at the Cleveland Clinic. Notably, since there aren't clear brain lesions in those with congenital prosopagnosia, scientists don't fully understand what causes it.

In comparison, individuals who acquire prosopagnosia later in life may have lesions in the brain that resulted from a head injury or trauma. According to Bonakdarpour, people can also acquire prosopagnosia after a stroke or while they are developing Alzheimer's disease.

What are the treatments for prosopagnosia?

Currently, there is no treatment for prosopagnosia, Bonakdarpour noted. However, the condition can be managed. Individuals with the condition often try to focus on features like hair color, walking style, or voices to differentiate between people.

Typically, neurologists diagnose the condition through a series of tests that assess a person's ability to remember and recognize faces. "It can be a lengthy process, as doctors often take pains to assure a patient's face blindness is not a symptom of a wider degenerative neurological condition," Blum writes.

Notably, many people who have the condition—like Pitt—will not receive a formal diagnosis. "Many of the challenges he's describing, the problems he has, are not atypical for folks who experience it," Stojic said.

"It be can relatively debilitating for people," he added. "It's hard for other people to understand." (Blum, New York Times, 7/7)