Stuttering Therapy:

A Comprehensive Guide

by William D. Parry, J.D., M.A., CCC-SLP

  Stuttering and Valsalva Stuttering | The Valsalva Mechanism | The Valsalva Hypothesis | Stuttering Therapy | Electronic Devices | Stuttering Research | Valsalva Control

NOTE: The following article was written prior to my recent clinical trials of Valsalva Control Therapy, which produced important refinements to the Valsalva Hypothesis and improved therapy techniques.  Therefore, please see my new articles:


Valsalva Control Stuttering Therapy: A Brief Introduction, and


New Insights and Tools To Beat Stuttering Blocks, based on my presentation at the National Stuttering Association conference in Ft. Worth, Texas, on July 7, 2011, including the results of my first clinical study of Valsalva Control Therapy and videos from my current trial of intensive Valsalva Control Therapy.

Stuttering and "Valsalva Stuttering"

Stuttering (sometimes called "stammering") is a specific kind of disfluency, in which the flow of speech is involuntarily disrupted by forceful closures of the mouth or larynx, by repetitions or prolongations of sounds and syllables, or by hesitations or delays in making voiced sounds. Stuttering generally involves an excessive amount of effort, force, and struggle in the attempt to speak. It also may be accompanied by a variety of secondary behaviors intended to avoid, postpone, or hide the blocks.  

Most people who stutter are able to speak fluently some of the time, but on other occasions their speech is blocked. Stuttering is a complex and multi-faceted condition which, depending on the individual, may involve a combination of learned behavior and various neurological, physiological, and psychological factors. Some people who stutter become adept at covert stuttering, by substituting words and avoiding situations in which they fear they will stutter.  (For additional information about stuttering in general, see The Stuttering Experience, on this website.)

"Valsalva stuttering" is this author's term for describing what appears to be an extremely common type of stuttering behavior.  In "Valsalva stuttering," the stutterer instinctively activates the body's Valsalva mechanism in an attempt to force out words, particularly when he or she anticipates that speaking will be difficult or that extra effort is needed.  The symptoms of "Valsalva stuttering" include:

bulletExcessively forceful closures of the mouth or larynx, either of a sustained or repetitive nature, accompanied by tightness in the abdominal muscles and increased air pressure in the lungs; and
bulletDelays in phonation (the production of voiced sounds in the larynx).
bulletRepetitions or prolongations of initial consonant sounds.

In some instances, Valsalva stuttering might be masked by covert stuttering or secondary avoidance behaviors (e.g., hesitations, repetitions, interjections, "starters," circumlocutions, etc.) . In those cases, one should focus on the underlying stuttering behavior that the person is trying to avoid.

While not all stutterers may exhibit Valsalva-stuttering behaviors, it is likely that a large majority do.  (The author's observation of hundreds of stutterers over the past 24 years indicates this to be the case.)  However, speech-language pathologists are almost never taught about the Valsalva mechanism, are generally unaware of its possible involvement in stuttering, and are not prepared either to diagnose or to treat it. While therapists may encourage stutterers to relax the lips, tongue, and larynx, these are only the tip of the iceberg.  Control of the mouth and larynx will be difficult as long as therapists ignore the physiological mechanism providing the force behind the blocks.

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The Valsalva Mechanism

The Valsalva mechanism consists of neurologically coordinated muscles in the mouth, larynx, chest, and abdomen. It is designed to perform a Valsalva maneuver to increase air pressure in the lungs by forcefully closing the upper airway while the chest and abdominal muscles contract. This assists us in many types of physical effort and in forcing things out of the body.

The ordinary Valsalva maneuver involves tight closure of the vocal and vestibular folds of the larynx (called effort closure) for the purpose of sealing off the respiratory tract, accompanied by contraction of muscles of the abdomen and chest. The various elements of the Valsalva mechanism appear to be linked neurologically so that they tend to contract simultaneously. The force of the closure is in proportion to the amount of pulmonary air pressure being resisted.

Ordinarily the Valsalva maneuver (with its accompanying effort closure of the larynx) is done instinctively, without conscious thought.  This occurs in normal, healthy persons during lifting, pushing, pulling, defecation, natural childbirth, and other strenuous tasks.  (During activities such as lifting, the rectal muscles also contract, to prevent accidental evacuation of the bowels, but during defecation they do not.)  However, a person can also either perform a Valsalva maneuver on purpose, or consciously refrain from doing one.

The forceful closures associated with a Valsalva maneuver need not be limited to the usual effort closure of the larynx, but may instead involve tight closure of the lips or tongue, depending on which structure initiates blockage of the airway. Consequently, forceful closure of the lips and tongue may occur during the articulation of certain consonants, while forceful closure of the larynx may occur during the initial articulation vowel sounds (known as coup de glotte or "glottal attack" and sometimes referred to as "hard onset").

The Valsalva maneuver is also known to interfere with the playing of trombones and other brass musical instruments.

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The Valsalva Hypothesis

The Valsalva Hypothesis postulates that excessively forceful closures of the mouth or larynx associated with certain types of stuttering, as well as difficulty in phonation, may involve a neurological confusion between speech and the human body's Valsalva mechanism.

Persons who stutter may have learned to activate the Valsalva mechanism in an effort to produce words, as if they were things to be forced out of the body.  Such activation is most likely to occur when the stutterer anticipates difficulty or feels the need to use extra effort to speak properly.  While this might instinctively feel like the right thing to do, it actually makes fluent speech impossible.

When a person who stutters prepares to exert effort in speaking, excessive neuromotor tuning of the Valsalva mechanism may occur.  Such tuning may:

render the Valsalva mechanism over-excitable to triggering stimuli, such as the increase in subglottal pressure that accompanies the start of articulation;


interfere with normal prephonatory tuning of the vocal folds (because the larynx is instead being neurologically tuned for effort closure), thereby causing delays and difficulty in phonation; and


contribute to abnormal laryngeal behavior, either by increasing the strength of laryngeal reflexes (the Valsalva maneuver is known to strengthen reflexes), or by interfering with the suppression of reflexes, which normally occurs during speech.

The Valsalva Hypothesis views the Valsalva mechanism as only one of many factors involved in stuttering.  For example, a stutterer's anticipation of difficulty might be affected, to varying degrees, by attitudes, expectations, neurological impairments, or emotional factors. 

Furthermore, a child's original disfluencies may be caused by a variety of neurological, psychological, or developmental factors not involving the Valsalva mechanism. These original causes may be different for various individuals, but their commonality is that they create the perception that speech is difficult and will require extra physical effort.  The child — already accustomed to using the Valsalva maneuver when exerting effort or expelling bowel movements — may instinctively assume that words can be forced out in the same way.  Continuation of this behavior during certain critical years of childhood may influence the development of nerve pathways in the brain.  Over time, these behaviors become deeply rooted in the nerve pathways of the brain, making them extremely difficult to change.

For further discussion of the Valsalva Hypothesis, see Stuttering and the Valsalva Mechanism: A Key to Understanding and Controlling Stuttering.

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Stuttering Therapy

At the present time there is still no reliable "cure" for stuttering. Although many individuals benefit from various forms of speech therapy, there is no therapy, device, or drug that is effective all the time or for all people who stutter.  Methods that appear to help some individuals may not work for others.

Many "fluency" programs require the stutterer to abandon his or her normal way of speaking or breathing (even when fluent) and to learn artificial and unnatural speaking and breathing techniques that are supposed to prevent stuttering. The fluency-enhancing effects of many speech therapies may be attributed to their indirect effects on the Valsalva mechanism - such as by utilizing light contacts in articulation, easy onset of vowel sounds, emphasis on phonation, release of air prior to speaking, slow or stretched speech, breathing techniques, etc. However, none of them focuses directly on controlling the Valsalva mechanism itself. Although these methods may temporarily produce a kind of "fluent" speech, many patients complain that it sounds phony and unnatural, lacks spontaneity, and takes too much mental concentration and/or physical effort to maintain.  The initial level of fluency is difficult to sustain and relapses are common.

Typically a stutterer may attend an intensive "fluency shaping" program, lasting as much as three weeks and costing thousands of dollars.  During the program, the stutterer learns a new speaking technique, which may include various "targets" or "controls."  At the end of the program, he or she may emerge with a high degree of fluency.  Then comes the hardest part - trying to maintain that level of fluency by continuing to practice the "targets" and "controls" in the real world.  Follow-up studies are sometimes conducted to determine how fluent the person remains after several months or years.  The original fluency often deteriorates over time - sometimes quite rapidly - leaving the disappointed stutterer with no understanding of why the technique temporarily worked or why it ultimately failed.

Some therapies, such as "stuttering modification" programs, view the blocks, repetitions, and other manifestations of stuttering as separate learned behaviors, which the stutterer is encouraged to identify and to replace with more fluent behaviors.  The result is sometimes referred to as "fluent stuttering."  Again, the focus is primarily on the mouth and larynx, with no attempt to identify or modify activity in the Valsalva mechanism.  

"Stuttering management" programs try to teach stutterers to "manage" their stuttering, rather than trying to become fluent.  However, these programs do not include management of the Valsalva mechanism.

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Electronic Devices

Throughout the years, a wide variety of "anti-stuttering" devices have appeared on the market to alleviate stuttering.  In recent decades they have taken the form of sophisticated electronic gadgets. These have included miniature electronic metronomes, such as the Pacemaster, worn like a hearing aid; the Edinburgh Masker, which produces a noise that prevents stutterers from hearing the sound of their voice; the Fluency Master, which amplifies vocal vibrations; the Vocal Feedback Device, featuring an electronic vibrator on the throat; miniaturized delayed auditory feedback (DAF) devices, such as the SpeechEasy; and frequency altered feedback ("FAF") devices, which cause stutterers to hear their voice at a different pitch (including the SpeechEasy, which combines FAF with DAF).

As discussed at length in Understanding & Controlling Stuttering, the fluency-enhancing effects of delayed auditory feedback (DAF) and frequency altered feedback ("FAF") have been known in the laboratory for many years, although the reasons are not thoroughly understood.  The author of Understanding & Controlling Stuttering suggests ways in which DAF and FAF might promote fluency by affecting the "Valsalva-stuttering cycle."  Therefore, the principle behind the recently publicized SpeechEasy is not new.  What's new is the miniaturization of the device so it can be worn in the ear canal.  While many stutterers report benefits from the SpeechEasy while wearing it, it is expensive, the results are not perfect, and background noise often causes a problem.

None of these devices should be regarded as a "cure" for stuttering.  They only reduce stuttering while they are being worn, and their long-term effectiveness has yet to be proved.  Because they work by changing the way you hear your own voice, you must begin talking before they kick in.  Therefore, they won't help you get through a silent block.  You must you start vocalizing first, for example, by beginning your speech with an "ahh" sound.  Furthermore, these devices do little or nothing to increase a your understanding of stuttering or ability to control stuttering on your own.

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Stuttering Research

While no one doubts the importance of basic research on stuttering, there is also a need for research to provide immediate relief for people who stutter.  Much of the current research is focused on new imaging techniques, such as PET scans and fMRI scans, which produce colorful computer-generated pictures showing differences in the way stutterers' brains function compared to non-stutterers.  This is exciting stuff, but we have yet to see anyone overcome stuttering simply by looking at brain scans.  Genetic research has shown that susceptibility to stuttering may be inherited in many cases, but it's not likely that we will see gene therapy for stuttering during our lifetime.

Other research has focused on pharmacological ways to reduce stuttering, including various drugs that block dopamine receptors in the brain.  Clinical trials are now underway on pagoclone, an anti-anxiety drug that acts as a gamma amino butyric acid (GABA) selective receptor modulator. Although such drugs seem to produce a modest reduction in stuttering, the question remains whether taking drugs is worth the long-term risk of side effects, if an equal or greater increase in fluency might be achieved by non-pharmaceutical means. 

Meanwhile, stuttering research has almost completely ignored the possible involvement of the Valsalva mechanism in stuttering behavior - which, if properly understood, could bring immediate, practical benefits to many people who stutter, for no additional cost and with no harmful side effects.  While the Valsalva mechanism is well known to medical science and even trombone players, it is rare to find it mentioned anywhere in the speech pathology literature. Consequently, information about the Valsalva mechanism is not conveyed to speech therapists or to their clients.

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Valsalva Control

Valsalva Control is a comprehensive new approach to reducing the frequency and severity of stuttering blocks by teaching the person who stutters to relax his or her Valsalva mechanism while speaking and to focus on the phonation of vowels. Rather than teaching a new way to speak, Valsalva Control is aimed at recognizing and controlling the physiological forces that interfere with speech.  Its goal is not artificial fluency, but freeing the stutterer's natural speaking ability and making speech easier and more enjoyable.  No individual Valsalva Control exercise or technique is claimed to be a panacea or an instant ticket to fluency.  Valsalva Control is holistic in nature, including a variety of exercises as well as changes in attitudes toward speech and stuttering.  Rather than offering a quick fix, it seeks to provide tools for lasting improvement.

Valsalva Control should be seriously considered as a supplement to stuttering therapy because it is:

The only approach that directly deals with Valsalva-stuttering behavior,


Simple, natural sounding, and consistent with normal speech,


Not based on artificial speaking techniques that sound unnatural and are difficult to monitor and maintain,


Harmless and non-invasive,


Without adverse side effects,


Without additional cost,


Easy to utilize by any SLP without the need for special equipment, and


Compatible with many existing stuttering therapy programs.

Valsalva Control is especially intended for those persons who show the symptoms of "Valsalva stuttering" mentioned above.  (Persons wondering whether they might be good candidates for Valsalva Control should look at Diagnosing Valsalva Stuttering: Suggested Criteria, on this website.) Although this approach may prove to be more suitable for some stutterers than others, the same is true for all other therapies as well.  In any event, Valsalva Control would give speech therapists a potentially valuable option to help their clients understand and control stuttering blocks.

Although there are not yet any scientific studies of Valsalva Control, anecdotal reports indicate that numerous persons have found Valsalva Control exercises to be helpful, even on a self-help basis.  However, for Valsalva Control to be most effective, one will probably need the help of a speech therapist who is familiar with this approach.  This author has personally observed dramatic results in a clinical setting.

For further descriptions of Valsalva Control, see The Principles of Valsalva Control and Beating Stuttering Blocks: Some  Basics Suggestions for Valsalva Control, on this website.

The Valsalva Hypothesis and Valsalva Control can radically change the way in which we view stuttering.  See A New Outlook on Stuttering, also on this website.

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Copyright 2002, 2004, 2009, 2010, 2011 by William D. Parry

Contact Information:


 William D. Parry, Esquire, CCC-SLP

A licensed speech-language pathologist and trial lawyer, offering stuttering therapy and counseling (including Valsalva Control stuttering therapy) in person in Philadelphia and over the Internet via webcam (subject to applicable law). 

Office: 1608 Walnut Street, Suite 900, Philadelphia, PA 19103
Phone: 215-620-6792




Stuttering Therapy and Counseling:

The Valsalva-Stuttering Network:
Beating Stuttering Blocks:
Stuttering and the Law:


Valsalva Control Stuttering Therapy is a new approach to improving fluency by controlling the physiological mechanism that may be causing stuttering blocks. For further information on Valsalva Control Therapy, visit Stuttering Therapy and Counseling at

The Second Edition (2000) (5th Printing updated in 2009) of Understanding and Controlling Stuttering may be ordered from the National Stuttering Association or

For information concerning stuttering self-help and support, please contact:

National Stuttering Association
119 West 40th Street, 14th Floor, New York, NY 10018
Telephone: (800) 364-1677 or (800) WE STUTTER
Fax: (212) 944-8244

Researchers and speech-language pathologists seeking further information about the Valsalva Hypothesis may e-mail me at:

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Last revised: 7/21/2011