Every time we speak, our brains have to meticulously coordinate the movements of some 100 muscles in the face, mouth, tongue, lips, and vocal cords. Those muscles then have to fire almost instantaneously to produce the right sounds.
Speech is complicated, to say the least — if something goes wrong at any point between the first neural signals and the last muscular contractions, it may result in difficulty speaking, or a disorder known as dysarthria.
“When you have an interruption in that pathway, you have dysarthria,” says Brooke Hatfield, associate director of medical health services at the American Speech-Language-Hearing Association.
Dysarthria Can Impede Speech
Given the myriad brain regions and muscles involved (basically all of them from the lungs on up), those interruptions can come in many forms. Dysarthria isn’t narrowly defined; it’s an umbrella term for any loss of muscular control that impedes speech.
As a result, it manifests differently in different people, depending on which system is affected.
“If you meet six people with dysarthria,” Hatfield says, “you’re not going to have any idea what those people will sound like until you hear them talk.”
It’s often characterized by slow, slurred speech that’s either too loud or too quiet, but beyond that it may sound hoarse, monotone, nasally, or robotic.
There are six basic subdivisions of dysarthria, distinguished by their typical sound but also by the part of the brain involved. A person may have a combination of several. They can arise from progressive diseases like Parkinson’s and dementia, congenital disorders like Down’s syndrome, and even traumatic brain injury, meaning dysarthria can strike at any age.
Read More: 5 Thought-Provoking Facts About Brain Function
What to do if You Have Trouble Speaking
Whatever the cause and symptoms, dysarthria can lead to frustrating communication challenges. In mild cases, people may simply have to speak more deliberately; in severe ones, they may be unable to vocalize any intelligible words.
But Hatfield says that working with a speech therapist (also known as a speech-language pathologist) can make a big difference, even in the worst scenarios.
“There’s quite a lot that someone can do to change their speech,” she says. “If you can make sounds, you can do something to improve.”
At the first sign of difficulty speaking, she advises seeing a doctor to have the underlying problem diagnosed and treated. Dysarthria isn’t necessarily a sign of serious medical issues, Hatfield says, “but you definitely want to know why it’s happening,” even if it’s not yet interfering with day-to-day life.
From there, speech therapists can determine which sounds a person is struggling with, then use specially tailored exercises to rewire the body so it can effectively produce them again.
Besides working to restore vocal function, people with dysarthria can also employ various tactics to improve their communication. They might use gestures, point to letters on an alphabet card, or start conversations with a specific word that gives the listener context clues for what follows.
That said, Hatfield notes that the burden of communication shouldn’t lie entirely with one party.
“It’s not always on the person with dysarthria to be understood,” Hatfield says. “Their partner has to meet them halfway.” Listeners can watch the speaker’s lips closely, ask them to repeat certain parts and ask yes or no questions, among many other strategies.
Read More: The Different Diseases Behind Language Impairment
How Technology can Help With Dysarthria
Even when speech fails completely, the modern age offers new methods for making ourselves understood. Text-to-speech technology, for example, allows people with severe dysarthria to speak through an automated voice that reads digital text aloud.
Some people — like Steve Gleason, the former football player who was diagnosed with ALS in 2011 — can even clone their own voice using recorded messages. More incredible still, scientists are making rapid advances in brain implants that can decode thoughts and translate them into sentences.
Hatfield also stresses that dysarthria is purely a matter of motor control — it doesn’t reflect a person’s cognitive ability, and unlike aphasia it has no effect on their capacity to understand speech.
“It’s not a language problem, and it’s not an intellectual problem,” she says. “Just because someone has trouble talking, you can’t assume they have problems with thinking.”
Read More: What Is Primary Progressive Aphasia?
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
National Library of Medicine. Laryngeal Motor Cortex and Control of Speech in Humans.
Science Direct. Dysarthria.
WebMD. Voice Banking: What to Know.
Nature. Brain implants that enable speech pass performance milestones.
National Institute on Deafness and Other Communication Disorders. Aphasia.
Cody Cottier is a contributing writer at Discover who loves exploring big questions about the universe and our home planet, the nature of consciousness, the ethical implications of science and more. He holds a bachelor's degree in journalism and media production from Washington State University.
