If you don’t personally know someone who stutters, it’s easy to forget an encounter with them. But obviously being made fun of, people who stutter face a lifetime of problems. The National Stuttering Association (NSA) is hoping to bring awareness to the seriously debilitating disorder this week from May 12-18.

“This annual event is a time for the NSA to work with speech therapists and the media in the hope that we can reach the thousands of people who stutter who still feel alone and isolated,” the NSA’s website, WeStutter.org, said.

While examining the brains of people who stutter, one 2011 study found that the problem may lie in the brain’s inability to coordinate what a person is saying and what they’re hearing. Comparing it to music from a clumsy orchestra, study researcher Martin Sommer told LiveScience that “the question is not single elements themselves, not the instruments. They all know their parts. The question is how to activate them in a coordinated and well-timed fashion.” Sommer found that certain parts of the brain’s left hemisphere, responsible for the movement that creates speech, didn’t activate. Thus, the right hemisphere tries to compensate, and stuttering occurs.

Stuttering affects an estimated one percent of the population, according to the NSA, and disproportionately affecting boys the most as they grow into adulthood — there are about four times more adult men who stutter compared to women. It begins around 2 to 5 years old, when most children are stammering their way through language development, but it never really leaves.

It’s inconsistent too. Some people who stutter may experience bouts of relief, only to have the stuttering come back more severe than before. “For most, when they are stuttering, it feels like their speech is out of control,” the NSA website says. “This loss of control is intermittent and unpredictable.” This unpredictability leads to a vicious cycle in which a person who stutters tries to speak quickly or force the words out mid-stutter, only leading to more stuttering.

In turn, the inability to communicate may cause embarrassment, anxiety about speaking, and behaviors based on the fear of stuttering again, which only lead to an increased severity of stuttering. An NSA survey on adults and kids who stutter found that, for the most part, their experiences remain the same throughout their entire lives. Eight out of 10 children who stuttered reported being bullied or teased. In response to the statement, “You avoid speaking situations because of your stuttering,” 20 percent of adults and 26 percent of children responded, saying they did it “a lot.” Meanwhile, only 20 percent of children and 15 percent of adults said “not at all,” with the rest falling in the “some” and “a little” category.

The survey also found that 40 percent of adults lost an opportunity to get a job or promotion because of their stuttering. In a separate survey on 36 men who all stuttered, every single one of them reported some form of discrimination based on their stuttering during the interview process. “Many participants were told not only of their mismatch for the specifics of the job or the likelihood of a detrimental impact on customers, but also of the possible negative impact on team dynamics if they were appointed, Clare Butler, author of the study, told HealthDay.

For those who stutter, there are treatment options — the earlier it’s treated, the better. Speech therapy has shown promise, with just one week of it reducing problems with stuttering significantly. In the case of James Earl Jones, the man behind Darth Vader’s voice, learning to speak aloud helped him overcome his stutter, while other famous actors (Bruce Willis, for example) claim that learning to speak in accents helped them. Perhaps one of the best things a person who stutters can do, however, is accept that they have a stutter and speaking openly about it with others.

The NSA is encouraging everyone to raise awareness of these issues through pretty much any means possible, from wearing one of their “Keep Calm and Stutter On” t-shirts to sending a press release to your local media. You can see what they’re doing to raise awareness here.