The neuroscience behind stuttering

Rachel Feltman: For Scientific American’s Science Quickly, I’m Rachel Feltman.Stuttering is a neurologic disorder affecting the timing, initiation and flow of speech, and it’s been documented throughout recorded history. Some folks even interpret a portion of the Torah as saying that Moses had a stutter. It’s also a fairly common speech variation, with around 5 to 10 percent of people stuttering for some portion of their childhoods and about 25 percent of that population continuing through adulthood. Roughly three million Americans speak with some kind of stutter, which can take the form of the repetition or prolongation of sounds, as well as interruptions in speech.But this phenomenon has received surprisingly little attention from the medical and scientific communities, and some experts say treatment options could use a major overhaul.On supporting science journalismIf you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.Just this year a group of physicians, speech-language pathologists, researchers and people who stutter came together to release the first-ever consensus guidelines on the condition. Gerald Maguire, a psychiatrist and researcher who stutters himself, helped make that happen. He’s the founder and president of Stuttering Treatment and Research Society, or STARS, as well as the chief of medical staff and the director of residency training in psychiatry at College Medical Center in Long Beach, California. He’s here today to tell us what modern science has to say about stuttering and what comes next.Feltman: Thanks so much for coming on to chat with us today. I would love to start by just hearing a little bit about the work you do and how you got interested in the topic of stuttering in the first place.Maguire: Thank you, Rachel. I’d like to say that I first became interested in stuttering probably around age three, when I began to talk. I do remember stuttering as a little boy, age four or five, and was always kind of mystified, like, “What’s different in my brain? What’s going on here? How is it that I can sing”—I don’t sing on key, but I can sing the, the term fluently. Um, everything else seemed okay, but—“How is it that I get stuck on these words? How is it that I get anxious about things and thinking about what words I was gonna say?” So it began then, and I remember, every New Year’s Eve, saying, “Okay, my New Year’s resolution: I’m not gonna stutter next year.” You’re seven, eight years old, and by 12:02 A.M., I was stuttering again. So I said, “There’s something here,” and I, kind of, committed even back in, you know, I remember in intermediate school, definitely by early high school, that I wanted to go to medical school to try to see what’s going on, to see if I could help myself and maybe help others with this.Feltman: Yeah. Well, and could you tell us a little bit about your own experience of stuttering and what that’s like for you because I understand that there’s a lot of variation.Maguire: Yeah. So stuttering, it’s, for me, you know, for most of us, the vast majority of us, begins in childhood, so I’m no different than that. There’s quite a variability. We know that stuttering’s likely not one cause. I do have a strong family history. My older brother, who’s since passed away, he s- stuttered. Uh, I have family members on my mother’s side who also stutter. So it’s got to be some familial or genetic component with me that plays a role.For me, it was early on. It was a great amount of avoidance, mental exhaustion, even physical exhaustion, thinking about what word I was gonna say. “How am I gonna avoid a certain situation where I might have to say my name?” So tremendous avoidance, social anxiety and then, um, blocking on the words themselves.So that was kind of a, a snowball effect. The avoidance made the stuttering worse, and the stuttering would make the avoidance worse, and the so- social anxiety. We know that people who stutter do have a high coexistence or comorbidity with social anxiety, even depression. Fortunately I didn’t struggle with that. My late older brother did.And then my journey was that—and I remember speaking in front of class or especially going into my college years, even in my f-, early on in, uh, my medical internship as a physician—trying to avoid use of the phone. The phone is, for me, was an extreme barrier. Saying my name was always something. And that’s not unusual. I’m more common in that with others. But so compensating for that, like, as an intern, a first-year resident, just not answering the phone, just going to wherever part of that hospital was and just being awake all night to answer that question that could have, for most clinicians, could have been a quick phone call. For me, I’m—right, the nurse is always like, “Well, he’s always attentive. This guy’s always here.” So. But for me, it was a compensation, and maybe it helped me become the physician I am today.Feltman: Yeah. I’m curious whether you could tell us about how portrayals of stuttering in the media compare to what the experience is really like. I mean, I know a classic mainstream example would be The King’s Speech. But what do you think the big misconceptions are in the media?Maguire: Well, unfortunately that stuttering is still—can be made fun of still. I, I’m so glad that The King’s Speech came out because at least it showed a humanistic side, that we should not make fun of stuttering. It really captured well, I think, the anticipatory anxiety that, that “Bertie” [King George VI], the king, had when approaching, especially, the microphone.[CLIP: Helena Bonham Carter as Queen Elizabeth in a clip from The King’s Speech: “My husband is, um, well he’s required to speak publicly.” Colin Firth as King George VI: “I have received, th- th- th-.”]I thought that was a, a very good portrayal of that. Of course, he wasn’t cured by any means. Maybe he was treated to some extent, which is great, and formed that relationship with his therapist and Lionel, Lionel Logue. But it’s not even that long ago that we had A Fish Called Wanda, which was not great.Feltman: Sure.Maguire: The Life of Brian, uh, you know, Michael Palin, he’s got a good center now in the U.K., but really making fun of stuttering and mocking stuttering. Uh, My Cousin Vinny was, had some really negative—um, a child growing up, you know, uh, laughing at Porky Pig and others.[CLIP: Porky Pig in an episode of Looney Tunes speaking with a stutter.]So the media portrayals are still there and have been there for, to make fun of stuttering. But fortunately, I think we’re, The King’s Speech was a, a tremendous step for- forward for us, I believe. And, uh, I’m not sure that the, the types—that’s all they had then—was this behavioral form of therapy, seemed to maybe help him with that, which was—but he still—remember, I remembered speaking to the screenwriter of this, that it was inspiring that still the king was able to get on the radio and speak, which was great. Um, and so I think that is an inspiration to not have your voice silenced because you stutter. And so I think that was a great message from The King’s Speech.Feltman: So something that I found really surprising when I was reading about your organization was that the first consensus medical guidelines on stuttering that you guys helped come up with only came about this year. There’s a lot to unpack there, but maybe we can start with, you know, “Historically, how has stuttering been discussed and defined and treated?” And then we can get into a little bit how that’s changing.Maguire: To me, it’s interesting, is that stuttering has occurred throughout recorded human history. We know that Demosthenes, the Greek orator, ancient Greek orator [stuttered]. There’s even, uh, references to Moses being a person who stutters. So—but it’s amazing to me that when we founded STARS, Stuttering Treatment and Research Society, just less than two years ago, we were able to claim the domain stutteringresearch.org. Just think about that. That—where has this been? So there’s been just a lot of myths about stuttering. It’s been really ignored largely by the greater medical community.And so it’s had a tremendous history. I, I can’t explain exactly why. I wasn’t the first psychiatrist or physician to look at stuttering, definitely not. In fact, it was even—and I think this is what kind of led to it—there’s so much, so much information that was brought forward that didn’t turn out to be true that we kind of lost it. There’s kind of this division of psychoanalytic theories, like some of the Freudian theories about it, and then some of the behavioral theories through, um, different forms of speech pathology and the phys—and that they didn’t really lead to great results for the majority of people who stuttered. So it, kind of, lost, and people kind of gave up. And so even today, when I meet with my fellow physicians, and I say, “Well, yeah, we know, we now know that stuttering is neurologically based.” And they’ll say, “Wow, why don’t we ever think about this? Why don’t we ever study it?” Stuttering is more common than, say, Tourette’s disorder, yet there’s many more treatments, there’s more understanding of that condition, which is great, that we have that understanding. But stuttering’s been kind of held in, I don’t know, I just—maybe because the thought that we persons who stutter can have a good day and bad day, there’s great variability. That’s true in Tourette’s disorder, too. It’s true in social anxiety. So I’m, we just got to bring it out of the darkness. I can’t explain why, except that it’s been largely ignored. And, uh, we aim to change that.Feltman: Yeah. In the comparison to Tourette’s, I almost wonder if there’s some aspect of stuttering being a, something that i—sort of the, the onus is on the speaker and the person who stutters to decide, you know, to avoid a phone call or something of that nature. And, you know, Tourette’s, you know, is seen as more, quote, unquote, “disruptive,” um, and it’s, you know, such a bleak reason for one to be researched more than the other. But I can’t help but think that might be true.Maguire: But part of it could also be, you know, my friend Greg, uh, Mattingly, who serves as our chief medical adviser, Rachel, he also says, “Stuttering is where ADHD [attention deficit hyperactivity disorder] was 20 years ago.” People would think ADHD: “Well, this person just needs to focus. They’re flighty. They daydream.” But when we understand the neurology of it, now treatments are there; there’s greater understanding; the stigma goes down. I think complex brain conditions or disorders are misunderstood, and because there could be good days, bad days, we don’t know the fluctuations and so forth, there’s a lot of misunderstanding.And that the brain is really the most complex organ system, much more than the heart or the kidneys, especially something around speech, which is more uniquely human. So I think the level of knowledge has been lagging, even understanding attention, cognition. So hopefully stuttering is where ADHD was 20 years ago. Or I even view depression: In my career as a psychiatrist—I finished medical school 35 years ago—depression used to be thought, unfortunately, “Oh, the person just needs to pull themselves up by their bootstraps, get out of bed and get a job. That’s gonna make it okay.” And so that’s kind of that thought about stuttering. “Slow down, relax.” So as we understand the neurology of it, I’m hopeful the advocacy improves the understanding, kind of like where we’ve been with other brain-based conditions like depression and ADHD.Feltman: Yeah. Well, what do we know about what’s actually, uh, going on in the brain when someone experiences a stutter?Maguire: Great question. I can’t say it’s true for everyone. We do believe there’s multiple subtypes, different causes. We do think there’s a disruption in the majority of us who stutter in a circuit of the brain that involves—like, we understand what word we wanna say just fine, Rachel. We have no difficulty with that. It’s in the timing and the initiation of the phrase. Now that’s, we believe this is through a region of the brain called the, uh, the basal ganglia, which is deep in the brain, kinda controls muscle initiation and motion. And the thalamus can play a role with that. The amygdala—so anxiety can disrupt it.But if we have, like, an external timer, like if we’re singing or we’re speaking to a rhythm, we can bypass that circuit, have another circuit. That’s why we’re fluent when we sing, ’cause there’s external timer rhythm. So we know there’s something in that circuit.We don’t know everything about that circuit. We know that for many people, we believe that dopamine, which is one of the neurotransmitters, regulates that circuit. We’re not saying that’s the only thing that’s involved. There’s likely other neurotransmitters, other neurochemicals, other ways to, kinda, work within the circuit. Not saying that’s the cause. Could be. We do know that [for] some children, this, this circuit pathway doesn’t fully form and can form later, the insulation on that wiring, so to speak, and maybe that explains why some children, by adolescent years, don’t stutter anymore. But we need to know more, and it’s—the symptom may look the same; it doesn’t mean that the treatments are gonna be the same and [that] the causes are the same. One could have hypertension due to a heart issue, a kidney issue, stress, anxiety. Maybe some medicines work for that.And so we do know that, for many people, medicines that regulate dopamine can treat stuttering. We need more data with that, uh, as well as with other medicines or even some sorts of, um, how do I say, neuromodulation. Deep-brain stimulations [have] been reported in a few people. That goes into that circuit [and] can be invasive. Transcranial magnetic stimulation—could it get deep enough?But also, we know that talk therapy can change the brain. We know this. And so we know that certain individuals with certain forms of talk therapy can be beneficial, too. So I’m hopeful someday we’ll have studies, and that’s what STARS is behind, is to look at “What are the certain types of treatments that help for one particular type of stuttering or for that particular individual and empower that individual to, uh, receive that care?”Feltman: Well, now that we finally have these guidelines, you know, I’d love to hear a little bit about what went into creating them and, and what you all agreed on.Maguire: So STARS, we, we got together, we got a group together of 35 of us, uh, physicians of multiple specialties, psychiatry, neurology, pediatrics, primary care, also leading speech-language pathologists, neuroscience researchers and persons who stutter themselves, to put together—it’s more of a call to action in that [the] majority of us, you know, what we came up with, a consensus: that the current understanding is poor. That we do believe that stuttering’s neurologic, it’s brain-based. That hopefully can help decrease some stigma, help energize the field to move for-, forward. We do believe that the current state of understanding of health care in general, not just in the medical field but across all, all health care professionals, is low. It’s a poor understanding of stuttering, like, the current states of treatments that are available are poor.We do believe that intervening earlier in a child can be beneficial. We need more studies showing this. We need studies showing that we believe that, you know, some individuals, certain medications like the dopamine medicines can be beneficial. But we need more research looking [into] which individuals, when do we—and even looking at what types of talk therapy combined with types of different pharmacotherapy or medical therapies together. It’s probably gonna be a, what we see with ADHD and depression, that combining treatments are gonna be the best.We got together because the field needed it. Um, we’re a nonprofit. We’re an all-volunteer board, and, and we say, “Hey, this is a call to action for the rest of the field, the greater scientific community and medical communities to notice us and help us answer these questions.”Feltman: Yeah. Well, if any of our listeners are interested in, in getting involved in research, if it, it’s relevant to them ...Maguire: Yeah ...Feltman: Where should they go to look for it?Maguire: I think a great resource and one that we have developed here at STARS is stutteringresearch.org. Follow us on that. We put out newsletters. We’re getting information out to physicians and other health care professionals, individuals. We have a podcast. We’re beginning a webcast to answer questions and be that resource, like, global resource. And that resource is translatable on the website to multiple languages. We update it every week. So we have guides for parents, for persons who stutter, for physicians, for speech-language pathologists, other health care professionals. So very easy to remember, stutteringresearch.org.Feltman: Well thank you so much for, uh, coming on to talk with us today.Maguire: Appreciate it very much. Thank you.Feltman: That’s all for today’s episode. We’ll be back on Monday for our weekly science news roundup.Science Quickly is produced by me, Rachel Feltman, along with Fonda Mwangi, Sushmita Pathak, Allison Rodgers and Jeff DelViscio. This episode was edited by Alex Sugiura. Marielle Issa and Aaron Shattuck fact-check our show. Our theme music was composed by Dominic Smith. Subscribe to Scientific American for more up-to-date and in-depth science news.For Scientific American, this is Rachel Feltman. Have a great weekend!