Stuttering linked to genetics, motor control
February 19th, 2011
05:14 PM ET

Stuttering linked to genetics, motor control

Jennifer McGuire remembers how, as a child, she would order only certain things at restaurants because they would be easier to say. McGuire, 30, has stuttered for as long as she can remember.

"Stuttering has colored my whole life," she said Saturday. "Only recently has it not been the first thing I think about when I get up in the morning and the last thing before I go to bed."

Stuttering typically starts around 2 to 4 years of age, after the stutterer already had learned language, which is why legendary psychoanalysist Sigmund Freud thought it had something to do with parenting or something else in the environment.

But scientists have found copious evidence that biological mechanisms in the brain can explain stuttering. They presented some of the more recent findings at the American Association for the Advancement of Science meeting in Washington, D.C.

Stuttering is the central issue in "The King's Speech," nominated for Oscars in 12 categories at next weekend's 83rd Annual Academy Awards. The film hits home for many people who have lived with a stutter.

About half of stutterers have a clear family history of this speech disorder, said Dennis Drayna of the National Institutes of Health. But Drayna thinks this is in an underestimate for the genetic influence.

Drayna's research on the genetics of stuttering has shown that genes that appear to be involved all control some aspect of cell metabolism. The mutations linked with it are also associated with genes for rare childhood diseases called mucolipidosis type 2 and type 3. Those who suffer type 2 typically don't live to the age of 10, those with type 3 live only into young adulthood. But it has been noted anecdotally that those who live to age 7 or 8 with type 2 often don't ever develop the ability to speak.

The brains of people who stutter seem to have particular signatures in function and structure. Luc De Nil of the University of Toronto and colleagues used functional magnetic resonance imaging to look at what's going on in the brains of children and adults who stutter. It seems that the speech-motor control region of the frontal cortex, the premotor cortex and the cerebellum are all involved, while there is an underactivation in the auditory cortex. There are also clear differences in stuttering adults and children in terms of brain anatomy: the gray matter cortex and white matter intercortical connections appear different in them. These underlying structural differences appear to explain at least some of the functional differences seen in these individuals. Moreover, patients who develop a stutter after a stroke often have lesions in the same areas of the brain implicated in stuttering, De Nil has found.

Stuttering also appears to be related to motor coordination. In an experiment with children, De Nil's group also found that children who stutter have more problems learning sequences of finger-tapping than those who do not have the speech disorder. Those who stutter have more difficulties with the timing of sequential movements.

This seems to be a problem in movements of the mouth and jaw, previous research has shown in people who stutter.

"We’ve been able to show that the discoordinations are present even when people who stutter speak fluently," he said.

It's possible that because motor coordination and stuttering are linked, the degree of a patient's motor deficiency may predict how well he or she will respond to stuttering treatment, De Nil said. This idea needs more research, however.

In as many as 75% to 80% of stuttering cases, a child will recover spontaneously from stuttering, and there's no clear reason why some do better than others, said Anne Smith, researcher at Purdue University. Parents should try to help their children immediately, rather than ignoring the problem, if they pick up on speech difficulties.

The most painful part of stuttering is blocking: When you open your mouth to try to say something and nothing comes out, she said. This can lead to a lot of stress. What stuttering does to a person’s self-confidence and freedom to speak is depicted well in "The King's Speech," De Nil said.

As for McGuire, she is now pregnant, and is paying close attention to the research regarding genetics and brain characteristics in stuttering. She finds it exciting.

"It would be great if my child ends up being a person who stutters, but is able to have it be less mysterious, and have access to effective therapies and an earlier stage in life."

soundoff (164 Responses)
  1. judy

    Mcuire, why would you ever hope your child stuttered? You state tjhat you've been through it, but you must be ingorent to feelings! This isn't an experiment, it's life, and it hurts unbelievely. It can totaly shut you down emotionally. No one should have to go through the humilation of not being able to speak in front of a class fearing that kid in the back is going to laugh at you again, again and again. I hope no child ever has to go through life stuttering again. The self confidence recovery period is endless. Adults learn "tricks" to get around it, but it's never easy to live with. Never wish for someone to stutter. Everyone one is different and no one "cure" works for everyone. Good luck with you child.

    February 20, 2011 at 00:19 | Report abuse | Reply
  2. Jimi

    ... and a lisper is a sign of a helmet licker then??

    February 20, 2011 at 00:33 | Report abuse | Reply
  3. San

    Realise OR Realize ? Ssstttooopp Does Someone have a Chip on the shoulder?

    February 20, 2011 at 00:34 | Report abuse | Reply
    • Zaskya

      — not how they say it.3. Maintain natural eye cctnaot and wait patiently and naturally until the person is finished.4. You may be tempted to finish sentences or fill in words. Try not to. Use a relatively relaxed rate in your own speech — but not so slow as to sound unnatural. This promotes good communication.5. Be aware that those who stutter usually have more trouble controlling their speech on the telephone. Please be patient in this situation. If you pick up the phone and hear nothing, be sure it is not a person who stutters trying to start the conversation before you hang up.6. Speak in an unhurried way — but not so slowly as to sound unnatural. This promotes good communication with everyone.There are no instant miracle cures for stuttering. Therapy, electronic devices, and even drugs are not an overnight process. However, a specialist in stuttering can help not only children but also teenagers, young adults and even older adults make significant progress toward fluency.The Foundation lists specialists on their web site for speech therapy for stuttering. Click on "referrals" and find the country and state you need. If going to a specialist is not possible, get the Foundation's book "Self Therapy for the Stutterer."

      March 3, 2012 at 21:30 | Report abuse |
  4. Lefty McRighty

    Don't feed the trolls.

    February 20, 2011 at 00:44 | Report abuse | Reply


    February 20, 2011 at 00:59 | Report abuse | Reply
  6. DLoveSL

    Question: Why is it so hard for U's 2 ignor Dane, it's like they punched u or somethin. Some of the things were funny, you do have to learn how laugh! Worry about it when it turns physical, otherwise, sticks & stones love... ;p

    February 20, 2011 at 01:01 | Report abuse | Reply
  7. Ladybird

    I know a family of 10 where all of the boys moderately to severly stutter, but all of the girls speak perfectly and have never stuttered.. Absolutely, it's genetic.

    February 20, 2011 at 01:04 | Report abuse | Reply


    February 20, 2011 at 01:17 | Report abuse | Reply
  9. DLoveSL

    R U guys kidden? Your tellin me words on a screen upset U? My goodness, get over yourselves, & do what you came here to do, ignor them and grow up, your little children. (it's mine, no it's mine, no it's), can't u hear yourselves?

    February 20, 2011 at 01:20 | Report abuse | Reply
    • Natia

      I do not think it's forgotten child abuse to teach your cerldihn your beliefs, but it applies also to the Gentiles also. It's all right, but to teach Christianity to other cerldihn, but many do it and think it's okay, because it ist.BB faith

      March 4, 2012 at 15:14 | Report abuse |


    February 20, 2011 at 01:31 | Report abuse | Reply


    February 20, 2011 at 01:44 | Report abuse | Reply
  12. Jim

    i don't really believe this study or most studies regarding stuttering. I believe genetics could make you more suscpetible to stuttering, but outside factors contribute to it developing or persisting. Check out the "Valsalva Theory" regarding stuttering, it really makes a lot of sense and I think it's the most accurate description of stuttering and what causes it for most people.

    February 20, 2011 at 01:50 | Report abuse | Reply

    Miss jones enjoy while u can MRS. 68

    February 20, 2011 at 01:58 | Report abuse | Reply
  14. Frenchy

    My grandfather only became a stutterer after his parents tried to force him to write with is right hand (he was a lefty). I guess this blows their whole theory right out of the water.....but I'm sure that these scientists can make some kind of corollary out of that, like "Freud was right, some of the time".

    February 20, 2011 at 03:34 | Report abuse | Reply

    FREUDIAN Is the word used relating to Sigmund.

    February 20, 2011 at 04:07 | Report abuse | Reply
  16. rebecca

    Very interesting. The breathing technique is known as diaphragmatic breathing...I'm going to school to be a speech-language pathologist and have learned many different theories. I hope to help and learn more about therapy techniques to help fluency disorders. Wish me luck!!!!

    February 20, 2011 at 04:55 | Report abuse | Reply
  17. "Stu"

    Lol at the Moses in the desert joke.

    I recently started to stutter as an adult and attribute it to stress going through a forclosure sparked it.

    February 20, 2011 at 05:27 | Report abuse | Reply
  18. Lisa

    Im telling my age. But loved Mel Tillis. He is a stutterer but didnt when he sings. THEY need to research. Why people who stutter dont when they sing. And this was no gimmick.

    February 20, 2011 at 05:36 | Report abuse | Reply
  19. Dr.JOhn Jackson

    I am a physcian and surgeon and I stutter. I have had very good therapy but started after the age of 15. I was once told that I should not have been let into medical school and people who not see a black doctor who stutters. I have the busiest medical practice in the state and a 3 week waiting list to see me The only promlems I have had have been from a few ignorant medical instructers who thought it would be " funny" to make fun of me during hospital rounds.

    February 20, 2011 at 09:30 | Report abuse | Reply
    • Melanie

      I so admire you. My son stutters and I know he has suffered, though he rarely lets on. Good for you! You give us all courage.

      February 20, 2011 at 14:08 | Report abuse |
  20. Clark M. Thomas

    When I was a child I stuttered often. Nobody helped me. I "cured myself" when I simply paused before I began stuttering. Just before I would stutter my body tensed up, and I could hardly speak. By simply waiting a very few seconds before I began speaking my body relaxed, and stuttering vanished.

    February 20, 2011 at 09:55 | Report abuse | Reply
  21. Sankar

    My mom has casually mentioned about how I used to stutter when I was young.

    February 20, 2011 at 10:32 | Report abuse | Reply
    • Teresa

      Thanks for letting us know. We casually don't really know what to say?

      February 20, 2011 at 12:21 | Report abuse |
  22. Kendra

    My brother and I stuttered as children. I have spells here and there but for the most part have grown out of it. My brother does still stutter when he gets excited. Please note: not all stutters are nervous and need to "slow down" for their words to come out correctly. My paternal aunt who is in her 50's has a severe stutter, affecting every word that comes out of her mouth. Just so happens my boyfriend is a 38 year old science teacher and he has a steady stutterer. His father stutters and he has a son who has stuttering phases. So....of course I believe genetics are involved.

    February 20, 2011 at 10:33 | Report abuse | Reply
    • Jason

      Genetics appear to be involved here Kendra. Apparently some stutters can be controlled by the power of will and others can't. My sincere apologies for the plight your family is in. I hope technology can provide medicines to change the trend in your family's genetic line. Either medicines or proper breeding might change the trend in time.

      February 20, 2011 at 11:12 | Report abuse |
  23. Jason

    Advancements in Stem cells might be able to fix genetic defects prior too or at the time of birth by using nucleated eggs from alternate human donors. Why won't the government push through medical advancements for the rest of the world? Millions of dollars are being used fighting wars, curbing drug usage and providing aid to foreign countries, yet stem cell research has been on the back burner for years. The technology proves to exist, although the effectiveness may seem questionable isn't that how all technologies come about? We should save lives, not waste money on lesser things.

    February 20, 2011 at 11:08 | Report abuse | Reply
  24. Meggie24

    are you trying to be comical with your lame movie reference? If so, swing and a miss. Jerk.

    February 20, 2011 at 11:21 | Report abuse | Reply
  25. SassHattery

    Hmmm. Although based purely anecdotal evidence I disagree. After years of observation, most of the stutterers not only have absolutely no trouble with motor control, but in fact posses phenomenal motor control. Maybe this is only among those stutterers who are musicians? I'm not saying there might be a few cases that can be attributed to genetics, but the majority? If stuttering comes and goes, as stated in the article, maybe psychology plays a more important part than DNA. It'd be nice if when these type of articles that pop up spouting a 'new' medical theory, they could link it to multiple studies and not just a fantastical headline.

    February 20, 2011 at 11:45 | Report abuse | Reply
  26. drumguy

    I disagree with the link to motor coordination deficiency and ability to do sequential patterns. I'm a drummer (and a quite proficient one) and have been a stutterer since elementary school. Stuttering has had zero effect on my drumming. However, the genetic link is very probable - my father was a stutterer also for all his life.

    February 20, 2011 at 12:09 | Report abuse | Reply
  27. morris2196

    I have believed for many years that the cause of stuttering was neurological in origin. An obvious clue is that 90% of stutterers are male. I also have a personal experience that seems to confirm that. I have stuttered all of my life. It increased in severity when I was in my early 30’s. The quality of my handwriting also deteriorated substantially at that same time. Then I began taking a medication designed to treat anxiety called Tranxene, and BOTH my speech and handwriting improved.

    But I do not recommend Tranxene, because it is addictive.

    February 20, 2011 at 12:20 | Report abuse | Reply
  28. Jim Dixie player

    Actors never stutter on stage.... I never stutter when singing or talking with a microphone

    February 20, 2011 at 12:33 | Report abuse | Reply
  29. susan

    Stuttering runs in my family as well. I still have it though minimal and lm in my 40s. Blocking and repeating certain consonants such as the letters D S T. My neice has speech therapy and shes.doing very well with her speech and fluency. I would have to say that stuttering does have a genetic predisposition to it. Not everyone who gets nervous stutters.

    February 20, 2011 at 12:44 | Report abuse | Reply
  30. Maria

    Stuttering is linked to genetics. Well DUH!

    Enough said.

    February 20, 2011 at 13:33 | Report abuse | Reply
  31. Traveling521

    The phenomenon of stuttering ... just like any other physical manifestation ... will show up in the genes, but is not CAUSED by the genes. The predisposition to disease, cravings - and stuttering - begins at the "Field of Consciousness" level - which then starts shaping life energy into the uniqueness of that individual. Stress is what precipitates the "unloving" physical forms of that uniqueness. But before the forms become physically manifest, they are already being experienced as a sense of "how life is." Just as in the King's Speech - his long term "sense" that he did not "have a voice" – was also physically manifested as stuttering. Bruce Lipton's "Biology of Belief" and Luis Angel Diaz's "Memory in the Cells" addresses these concepts. Even the Bible says it .... "the Word becomes Flesh" - and the "word" is the information contained in the individual's Field of Consciousness - which is PRE-physical. The good news is that this "word" can be changed. I do it for myself and clients all the time. But it is not "therapy" - it is "transformation." And it requires feeling and moving the stuck emotion that holds the "unloving" beliefs in place - and then rewiring the subconscious with new, more loving beliefs. You can't do this by just "thinking differently." That's what I call "coping." Transformation requires feeling and owning the stuck emotion and the belief - and then CHANGING the belief. Unfortunately the medical model (which is only 4-dimensional) does not recognize the Field of Consciousness (which I think is about 8th dimension) ... so is left only with 4-dimensional tools and thinking. But people who have experienced spontaneous transformation - from "dark night of the soul," or "near death experience" - they know the difference. Your instinctive reaction patterns change - and your reality changes. Transformation is the source of spontaneous remission.

    February 20, 2011 at 14:16 | Report abuse | Reply
  32. Deb

    So fascinating. I had a friend in college that stuttered - except when he sang, or if someone read aloud with him. I've never had a reasonable explanation for this - would appreciate any pertinent information.

    February 20, 2011 at 14:33 | Report abuse | Reply
    • TWynn

      That's because stuttering is also a problem of timing. Something between the speech processing/commanding part of the brain and the speech articulators (vocal cords, lips, etc.) the timing is messed up. Imagine a conductor who can't conduct and time a performance of his band and you'll get an idea. Stutterers singing in a choir are fluent because of the help of an external timing device, ie other singers' cue or rhythm.

      March 2, 2011 at 12:34 | Report abuse |
  33. Russ

    Reading poetry helps stuttering. I know, it works for me.

    February 20, 2011 at 17:34 | Report abuse | Reply
  34. Kimberley

    I do not stutter but I do have a language processing disorder and I can't believe the vitriol that some members are posting on what is supposed to be a discussion site about stuttering...Yes, I believe in freedom of speech but what about kindness and thinking before one posts? People can be so cruel to those who are different, so why should we also give in to this kind of mean-spirited behavior...perhaps there are many causes of stuttering and just as many treatments and / or methods to help those so afflicted. I saw on TV a new method where a hearing aid-type device was put into the ear of a severe stutterer and it allowed him to speak almost without any difficulties! I also wish parents would teach their children to be kind to others instead of the old lie that 'children are cruel' as an excuse...I wish you all well and use your smart-Aleck humor on those who are stupid enough to mock you for your stutters...; )

    February 21, 2011 at 00:39 | Report abuse | Reply
  35. El Verdad


    February 21, 2011 at 00:52 | Report abuse | Reply
  36. yusa1929

    I stuttered as a child, it stopped at 17, I still can not hit a golf ball.


    February 21, 2011 at 09:57 | Report abuse | Reply
  37. Jimi

    I started stuttering at 12 and now I am 35 and still stuttering. I am able to control it more and appear "fluent" but my motor control has a deficit (I can feel it). Anyone who is exerting more force but appears fluent is still a PWS in my book. It is very disabling and takes a toll on a person's "well being". There is nothing "funny" about being in pain.

    February 21, 2011 at 18:47 | Report abuse | Reply
  38. george (the ?)

    I wonder what QEII thought about the movie. Anybody have any knowledge of that?

    February 21, 2011 at 18:57 | Report abuse | Reply
  39. John

    I was a stutterer until almost finished with high school when I overcame it by force of will and making myself slow down in my rate of delivery. No one else in my family had the problem. In my 30's I learned from my mother that as a toddler I never crawled, just stood up and walked one day. This reinforces the article's contention that stuttering is a motor control issue. Crawling is integral to the development of fine motor skills with which to this day I'm not the most proficient.

    February 22, 2011 at 17:06 | Report abuse | Reply
  40. Nwambe

    Of all these solutions, the ultimate cure for stuttering is this:
    You have to develop a thick skin. Once you don't care what other's think about how you speak, your stuttering goes away.
    Granted it takes a while to get there. Also easier said than done. As a parent with a toddler and infant, I know they will stutter but I will be there.
    My most important task I think will be to build up that thick skin while still practicing all the techniques to slow down while speaking.

    For me, I remember that even when I knew that slowing down and breathing helped, I was more concerned about whether someone would interrupt my sentence while I was trying to slow down. This makes me speed up and the stutter continues.

    Ultimate cure: Get the stuttering person to speak in public and let them stutter. If they can deal with the humiliation and survive the ordeal and do it often, they can deal with anything and eventually the stuttering will go away.

    Finally I learnt: Strength is strength and weakness is weakness but a show of weakness is a sign of strength and show of strength is a sign of weakness. If you are strong enough to show weakness and suffer humiliation, you can conquer all.

    That's why weak countries have parades showing their weapons and strong countries don't.
    That's why a strong person can let children bind him because he knows he can break the ropes.
    Finally, that's why God allowed himself to be bound and killed – to teach us strength through a show of weakness.

    February 26, 2011 at 11:00 | Report abuse | Reply
    • Sofie

      I think these parents luohsd be their child a religious theories unterrichten.Ich also think that parents need their children right from wrong teaching. Not everybody does it, however. They teach their children to steal, lie, etc. I have students tell me they get into trouble at home if they did not steal anything. *** *** Sad but true I'm 26 years lehrte.Keine school teaches students, we are apes.

      March 5, 2012 at 20:45 | Report abuse |
  41. Stuttering Chat


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  44. Thomas David Kehoe

    Please write a blog about my free e-book: "What Stuttering Treatments Are Effective?" It's a short, easy-to-read evidence-based review of 200+ studies. Download the e-book now from http://casafuturatech.com/stuttering-e-book

    August 16, 2012 at 12:59 | Report abuse | Reply
  45. cure for stuttering

    Very interesting. The breathing technique is known as diaphragmatic breathing...I'm going to school to be a speech-language pathologist and have learned many different theories. I hope to help and learn more about therapy techniques to help fluency disorders. Wish me luck!!!!

    December 18, 2014 at 04:53 | Report abuse | Reply
  46. help stop stuttering

    Very interesting. The breathing technique is known as diaphragmatic breathing...I'm going to school to be a speech-language pathologist and have learned many different theories. I hope to help and learn more about therapy techniques to help fluency disorders. Wish me luck!!!!

    December 29, 2014 at 06:20 | Report abuse | Reply
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    January 2, 2015 at 03:16 | Report abuse | Reply
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