Thursday, March 14, 2013

Simplified summary of Dr Schwartz's latest thinking on the cause of stuttering

The basal ganglia in the brain. Part of their job is to coordinate the vocal cords during speech. The basal ganglia's malfunctioning may result in a freezing of the vocal cords, leading to stuttering. 

Detailed view of the basal ganglia

Important summary of Dr Martin Schwartz's latest thinking on the cause of stuttering as follows, provided by Dr Schwartz himself per email. This is based on his article, "The Trigger for Stuttering", the full version of which can be read HERE.

1. Most of the struggle behavior which typically characterises stuttering is learned.

2. It is learned to release a locking of the vocal cords.

3. Traditional speech therapy attempts to work on the struggle behavior.

4. I attempt to work on the locking of the vocal cords.

5. Recent research suggests that the locking of the vocal cords represents a transient dysfunction of the basal ganglia under stress.

6. My recent article entitled "The Trigger For Stuttering" enumerates ten sources of stress which often occur simultaneously.

7. The vocal cords, in ongoing speech, have to open and close rapidly so they can meet the requirements for voiced and voiceless sounds.

8. They do this by making use of a principle in physiology called reciprocal inhibition.

9. Reciprocal inhibition means that when the muscles that close the vocal cords contract, the muscles which open them actively relax - and vice versa.

10. The basal ganglia control reciprocal inhibition of the vocal cords during speech.

11. When the basal ganglia cannot function properly there is a loss of reciprocal inhibition.

12. This manifests itself as a freezing of the vocal cords in an open or closed position, depending upon the phonetic requirements of the upcoming speech sound.

13. If there is a deficiency of thiamine or magnesium (for some) then the basal ganglia cannot function properly because there is a deficiency of a necessary neurotransmitter (perhaps GABA or acetylcholine).

14. For some people who stutter, if we give them thiamine or thiamine and magnesium, the basal ganglia can function normally and the locking of the vocal cords stops and thus the trigger is no more and without the trigger the stuttering is also no more.


  1. Excuse my english - but How do you do the link with the corticals abnormalities? (disconnexion, overcompensation)

  2. Dear Olivier, thank you for your question. I will try to get a response from Dr Schwartz. Kind regards, Peter

  3. I presume your question has to do with recorded cortical anomalies during stuttering. There are two possible answers.

    First, their are direct links between the laryngeal cortical areas and the basal ganglia. So any problem at the basal ganglia might be expected to manifest itself at the level of the cortex.

    Second, cortical effects, from other areas, are difficult to understand because they may reflect years of learned struggle behaviors and not core mechanisms.

    I hope this answers your question.

  4. I am pasting the Conclusion of the latest research conducted on Stuttering by the German Researchers here:

    Our experimental results demonstrate an involvement of
    the basal ganglia in PDS, both by showing a correlation of
    the activity in this region with severity of stuttering and by
    showing an impact of stuttering therapy on this activity.
    Based on these observations and a number of other findings
    available in the literature, we proposed a functional
    model of stuttering, in which a dysfunction of the basal
    ganglia would result from a structural anomaly affecting
    the information flow between Broca’s area (speech motor
    plans programming) and the motor cortex (execution of
    the motor plans).

  5. Dear Dr. Schwartz thank you for your life long interest in stuttering. Thirty years ago in Detroit you changed my life. I believe in passive air flow technique. It's a life long process of being mindful of your technique, practice, and controlling stress. I can't thank you enough for what your work has done for me. It was a pleasure to meet you. Enjoy your retirement. Debbie

  6. Debbie, I have forwarded your kind comment to Dr Schwartz per email. Many thanks - I am sure you speak on behalf of many, me included. He came to South Africa in the 1980s, and I was so fortunate to attend some of his workshops, which also changed my life just as it changed yours. All the best, Peter

  7. Peter, I read an article about the connection between stutering and sleap apnia. I have both. Following my verry good result with the B1 and magnesium I wondered if it had helped my sleep apnia. I had not been recording my data in the past 2 or 3 months but
    decided to do so now. My sleap does seem to measure a lot better that is I require a lot less presure to treat it. Most people with sleap apnia don't have a APAP that adjust the pressure as needed and records data. I may be the only one who responded strongly to the B1 for my stutering who also has a apap and could see it was also helping sleap apnia. True this could just be a fluke or maby the thiamin and B1 might help some people who just have sleap apnia.


  8. Dear Woody, many thanks. Interesting - I have googled "sleep apnea" together with "stuttering", and there is a lot of information there and research which has been done on a possible relationship between the two. I don't know much about the subject but will ask Dr Schwartz for his views.

  9. Woody, Dr Schwartz has replied that he has no information on this, but in my google search I found that in 2008 Dr Ronald Harper at the University of California and his team were in the process of studying thiamine levels in sleep apnea patients. He also advised such patients to take thiamine. This was in 2008 and I haven't found any follow-up research findings, so maybe that research didn't lead to anything. But it's still interesting that he advised patients to take thiamine. I have no more information unfortunately. You can check the relevant article at

  10. Thanks for the informative article. There are few well-known Speech Therapy For Stammering In Kolkata who provide speech therapy. Looking forward to more informative articles from you.