The Valsalva Stuttering Network

The Neurological Triggering of Stuttering Blocks

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

The scariest thing about stuttering blocks is that they tend to occur automatically, involuntarily, and without any conscious control.  Suddenly you are aware that an up-coming word is blocked – often before you even try to say it.  You feel as if it contains an insurmountable “brick wall.”  You become overwhelmed by a seemingly uncontrollable urge to use physical effort to force the word out.  You momentarily forget everything you may have learned about fluency techniques.  In your panic, you instinctively revert back to your old, established struggle or avoidance behaviors – as if no other choices are possible.  These experiences may leave you feeling helpless, confused, frustrated, and despairing of any hope for improvement.

The Fight-or-Flight Response

The triggering of stuttering blocks closely resembles what happens during the body’s “fight-or-flight” reaction to fearful stimuli.  For example, if you were hiking in the countryside and suddenly saw something at your feet that looked like a rattlesnake, you would automatically react to the danger, without even thinking.  Your brain is programmed to do this instantaneously as an aide to survival.   Your reaction might be particularly strong if you knew that the area was infested with poisonous snakes, and you were already worried about being bitten.

Here’s how it works.  The fearful stimulus – the vision of the snakelike object – is transmitted from the visual cortex of your brain to a part of the brain called the thalamus, which acts somewhat like a switchboard The thalamus relays the information to other parts of the brain, including the amygdala – a structure in your limbic system (or “emotional brain”) where fearful memories are stored.  (There is an amygdala on each side of the brain, but we'll just use one as an example.)

If the stimulus is similar to something fearful, the amygdala automatically sounds an alarm, telling the hypothalamus to begin the “fight-or-flight” response.  The hypothalamus does this by activating the sympathetic nervous system (a branch of the autonomic nervous system) as well as the adrenal-cortical system, causing various glands to release adrenaline (also known as epinephrine) and approximately 30 other stress hormones into the bloodstream.  These hormones cause the mind and body to prepare for emergency action to deal with the danger.  Your heart rate and blood pressure increase, your muscles tense up, your larynx may close to perform a Valsalva maneuver, and your brain becomes focused solely on responding to the threat.  Emotionally, you feel a jolt of intense fear.  As a result, you jump away from the snake-like object without even thinking.  Acting in response to the fearful stimulus helps to reduce the intensity of your anxiety.

All of this happens before your sensory cortex interprets the sensory data and your hippocampus compares it to other conscious memories in order to establish the proper context.  After interpreting all the data, you may determine that the object is not a rattlesnake after all.  Perhaps you determine that it’s a harmless garter snake or just a stick.  But that doesn’t matter.  The fight-or-flight response assumes the worst and follows the “better safe than sorry” principle.

After the perceived danger has been dealt with, the parasympathetic nervous system (another part of the autonomic nervous system) is activated and returns your bodily functions to their normal state.

The Valsalva-Stuttering Response

During speaking situations, a similar chain reaction may occur.  Your experiences may vary, but typically, the Valsalva-stuttering response seems to work like this:

·         You begin by entering the speaking situation with a variety of fears, attitudes, and negative expectations that increase the sensitivity of your fear response system.  These may include your image of yourself as a stutterer, your belief that speech will be difficult, your fear of making a bad impression by stuttering, and memories of stuttering in similar situations or when talking to the same listeners. 

·         Prior to the act of speaking, the language-processing parts of your brain select appropriate words and arrange them into sentences.  (Or, if you are reading aloud, your brain must decode the written words and translate them into speech.)  During this process, you come to an important word, or a word that is the same, similar, or begins with the same sound as a word on which you blocked in the past.

·         Almost instantaneously, your amygdala matches this word to fearful memories of the same or similar words or sounds.  It anticipates that you will have difficulty in saying the word.  Automatically, it sends an alarm to your hypothalamus. 

·         Your hypothalamus initiates the “fight-or-flight” reaction, causing stress hormones to flood your body and brain. 

·         Some of these hormones invade the area of your brain that is putting together the muscular motor program for saying the feared word.  In place of the motor program for phonating the vowel sound, it causes your brain to insert a motor program for your larynx to perform effort closure as part of a Valsalva maneuver.  This is what you first perceive as being the “block.”  You may feel as if the word contains a “brick wall” – which is actually the motor program for effort closure in the place where phonation of the vowel should be.  Without the motor program for phonating the vowel, you can’t say the word.  You can say other things, but not the specific word or syllable that contains the motor program for effort.

·         You may feel a jolt of fear.  You mind and body are taken over by the stress hormones, which focus your attention entirely on the struggle.  The stress hormones cause you momentarily to forget anything you may have learned in speech therapy.  They are screaming, “Force!  Force!”

·         Even if you remember what you are supposed to do, you feel totally out of control.  You experience an overwhelming urge to build up air pressure in an attempt to force out the word. 

·         In your panic, you find yourself reverting to the same kinds of repetitions, prolongations, blocks, and other struggle or avoidance behaviors that you used in the past. 

·         The more you attempt to force out the word, the stronger the blocks become, and the less the larynx is prepared to phonate the vowel sound of the word.

·         Blocking on the word reinforces your belief that speaking is difficult or that a particular word or sound is hard for you to say.  This increases the sensitivity of your fear response even more.  Therefore, your blocking on one word may increase the likelihood that you will block on others.

·         Exerting effort and force may temporarily reduce your anxiety.  You may get the false impression that effort and force succeeded in eventually getting the word out.  Therefore, these behaviors are rewarded and reinforced – even though they actually strengthen and prolong the blocks and perpetuate your stuttering.


When used appropriately, the body’s fight-or-flight response is an aid to survival, because it helps to keep you safe from dangerous situations.  However, it is not at all helpful for speech.  Nevertheless, you may have developed a strong attachment to your “stuttering alarm system” – perhaps because it somehow makes you feel safer.  Therefore, you may have a hard time giving it up – even though your reward would be easier and more enjoyable speech.

Overcoming stuttering requires a multi-pronged approach that reverses the Valsalva-stuttering response at every stage and at every level – psychological, neurological, and physiological.  This is the goal of Valsalva Control Therapy.

 Copyright  © 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
Mobile phone: 215-620-6792




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Last revised: 11/13/11