Stuttering & Automatic Speech: An In-Depth Look At The Unconscious’ Role In Speech Movements & Stuttering

Written by Matthew O’Malley

Traduction Française – Parole Automatique et le Rôle de Linconscient

Synopsis:  Speech is movement.  The process for speech movements (and all movements) begins unconsciously prior to the individual even becoming aware of their own intention to speak.  Speech is an automatic ability largely controlled by the unconscious mind, like walking or riding a bike.  When people who stutter begin to stutter, they begin disliking the loss of control that accompanies it and the reactions they receive.  As a result, people who stutter begin utilizing the conscious mind in the speaking process in an attempt to control speech, and consciously ensure they do not stutter.  This heightened use of the conscious mind interferes with the unconscious’ role in performing the speaking task.  I assert that the insertion of significant levels of consciousness into the speech process, at minimum, contributes to stuttering and further complicates it.  The findings shared below may go beyond implications regarding the automaticity of speech.


In previous posts, I shared extensively on automatic ability and how it may relate to stuttering.  Prior to diving deeper into this subject, I would like to go over some of the very basics of content I previously shared in regards to the relationship between speaking, stuttering, and automatic ability.  It is not completely necessary to have more background on the subject than what I share below for the point of this post.  However, the explanation below in the “macro view” is a brief summary of what I previously explained.  There is more thorough information on this here and here.

Also, just so you are familiar with the structure of this post, I am first going to share what I call a “macro view” of speech, stuttering, and automatic ability.  This macro view is based off of naked eye observations.  Following that I will share a “micro view” of speech and automatic ability which is based off of research and is more zoomed in to details.  The “macro view” is a summary of previous content on speech and automatic ability.  The “micro view” is all new.  I will then combine the micro and macro views and draw some conclusions about stuttering and automatic ability.

Macro view of stuttering, speech, and automatic ability

Firstly, what is an automatic ability?  An automatic ability is simply something a person is able to do without involving much, if any, of the conscious mind.  Examples of automatic abilities would be walking or riding a bike.  When you walk or ride a bike, you do not have to lend much attention or thought to making sure you move your legs correctly, nor do you have to think about any of the mechanics of the movements.  You simply know how to walk or ride a bike so you just do it.

For most people (people who do not stutter), speaking is an automatic ability.

My interest in automatic ability peaked when as a person who stutters I realized what I was experiencing when my speech control fluctuated.  When I experienced a drop off in control of my speech, I simply had less automatic speech.  I had to work more to get words out.  When my speech control fluctuated to a place where I had increased control, I had more automatic speech.

I started observing this more and thinking about what this observation meant.  I came to the conclusion that a problem in stuttering is the person who stutter’s attempt to consciously control their speech.  This is counterproductive because the implementation of an automatic ability and the exertion of conscious control do not coexist peacefully.

In diving deeper, when a person first begins to stutter in their life, they at some point begin to notice these involuntary disruptions in their speech.  Also, they begin noticing listener reactions to it.  This experience is unpleasant.  As a result of the unpleasantness, they look to assert control over their speech to avoid blocking and stuttering to avoid this unpleasant experience.  This process is cyclical and strengthens to a level where the person who stutters is consistently exerting conscious control over their speech.

Speaking is a complex process involving the coordination of fine motor control across a large number of muscles.  Some of these include controlling the muscles of the lips, tongue, and jaw; controlling the muscles that enable vocal fold vibration; controlling the muscles that impact breath inhalation and exhalation.  When contemplating the complexity of the task of speaking, it reasonably follows that the conscious mind is inadequately equipped to perform the task of speaking.  The vast majority of speaking must be performed by the unconscious mind.  There is no other way to do it properly.

Based on these observations, I surmised that if a person who stutters could let go of trying to consciously control their speech all the time, improved fluency would be the result.

Those are some of the very basics.  Like I said, to get a more comprehensive picture of these concepts, go here and here.

To reiterate, I think of what I described above as a “macro” perspective on stuttering and automatic speech.  I arrived at those conclusions based on observations I could make with the naked eye.  These “naked eye” observations were purposeful.  When I began a new quest to understand stuttering, I purposefully threw everything I knew about stuttering out.  I wanted to rid myself of preconceived notions I had learned or had been taught about stuttering.  I did not want to read about stuttering.  I wanted to observe my stuttering and others’ stuttering firsthand and come to my own conclusions.  Through that process, I came to much of what I’ve shared above on automatic speech.

However, after spending a couple years observing stuttering and coming to my own conclusions, I began investigating applicable research; much of which is not specifically designed to illuminate stuttering.  In transitioning from gross observations with the naked eye which informed my macro version of stuttering and automatic speech, I have now begun investigating a “micro” version.  Below, I will begin presenting in depth information based on research demonstrating how much of the speech-movement process is unconscious, and therefore must be performed “automatically.”  It is more zoomed in to the underlying neurological processes that enable human action/movement (including speaking actions).

Micro view of stuttering, speech, and automatic ability

Speech is a complex task involving the formulation of language.  However the physical performance of speech is movement.  When a person “speaks out loud”, movements of various parts of the person’s body are required.  The speaker must move their lips, tongue, and jaw which is nothing more than the contraction and relaxation of muscles.  The speaker must move muscles associated with the inhalation and exhalation of the lungs.  They must move muscles that enable vibration of the vocal folds.  The important point here is speech is movement.  When a person speaks out loud, they must move their bodies.  What I am about to discuss below is research that applies to the underlying neurological processes of movement (including speech movements).  For you to connect how this information can illuminate the processes of speech and stuttering, it is important to understand that speech is movement.  So, keep this in mind.


In the mid 1980’s, a research study was designed to explore the role of the conscious will in voluntary action.  The study was performed by a man named Benjamin Libet who was a pioneering scientist in the field of human consciousness.  Libet was the winner of the Virtual Nobel Prize in Psychology in 2003.  He died in 2007, however his research into consciousness still influences and affects various academic disciplines.

His study is widely known for its implications surrounding the idea of human free will and its legitimacy.  The findings of the study determined that the processes that are responsible for performing a voluntary movement of the body occur before the individual is even aware of their intention to perform that voluntary movement.  In other words, our brains begin the process of a movement before we are even consciously aware we are going to make that movement.

In an example:  Let’s say I am sitting in a chair.  Then I stand up to get some water.  There was a moment in my conscious mind that I became aware that I was going to stand up to get some water.  There was a moment that I “decided” to stand up.  There was a moment I became aware of my intention to stand up.  Libet’s findings reveal that prior to my awareness of my intention to stand up, my nervous system had already initiated the processes necessary for me to make that movement (standing up).  So, my unconscious mind had already begun making the movement (standing up) prior to my own awareness that I wanted to make that movement.  Do you see how this has implications into free will?

Sidenote:  I am not writing this to advocate for the existence or the lack of existence of free will.  I am indifferent in regards to making a case for either side.  I do not think these studies prove or disprove the existence of free will.  I simply believe the findings in these studies are highly applicable to stuttering.  This is the only reason I talk about the studies and free will at length.  In addition, there are different ways to interpret these findings and their implications into free will.  Whatever your religious, spiritual, or world view is, again, I am not presenting this information to sway anyone’s views on the subject.  I understand those views are important in a person’s understanding and approach to life and it is not my intent at all to sway anyone in either direction.

In explaining how these studies are applicable to stuttering I have to get into some detail.  It gets semi-technical, however, I try to explain it in a linear and clear way.

Research shows that the brain begins activating motor circuits responsible for a voluntary movement about 550 milliseconds before the voluntary movement is actually performed; that’s slightly more than a half second (Libet, 1985).  The person’s awareness of their intention to move occurs about 200 milliseconds before the actual movement is performed.  This is slightly less than a quarter of a second.  Doing some basic math, you can see that the brain begins activating for a movement approximately 350 milliseconds before the person’s conscious awareness of their own intention to make that movement.  The above times and information come from Libet’s study in 1985, titled “Unconscious cerebral initiative and the role of conscious will in voluntary action.”  You can find that study here.

Sidenote:  In continuing a bit on free will, based on the above study there was an assertion made instead about “free won’t.” (This will apply to stuttering.)  In the free won’t theory, the conscious mind’s role is to block and filter movements/actions.  Because a person becomes aware of their intention to move 200 milliseconds before they actually move, there is room in that 200 milliseconds to veto an action.  In essence, the free won’t theory states that despite the subconscious preparing a person for a movement before their awareness of their intention to move implying limitations on free will, the conscious mind still has the power of will to veto these actions.  When a person who stutters is excessively involving the conscious mind in the speech process, they are involving the part of the system that blocks movements/actions, according to the “free won’t” theory.


In four sentences, the concepts from the micro view above go as follows:

1 – Speech is movement.  2 – The unconscious mind begins processes (neurological systems activate) to perform a movement before the person is even aware they are going to make the movement.  3 – A few hundred milliseconds after the unconscious mind has initiated processes for a movement, the person becomes aware of their intention to make the movement.  4 – A couple hundred milliseconds after the person becomes aware of their intention to move, the movement is made.

Below are a few direct quotes from research articles that informed my summaries above.  You can also click on the links embedded in the citation to get the full context of the research.

“The subjective experience of conscious intention is a key component of our mental life. Philosophers studying ‘conscious free will’ have discussed whether conscious intentions could cause actions, but modern neuroscience rejects this idea of mind–body causation. Instead, recent findings suggest that the conscious experience of intending to act arises from preparation for action in frontal and parietal brain areas. Intentional actions also involve a strong sense of agency, a sense of controlling events in the external world. Both intention and agency result from the brain processes for predictive motor control, not merely from retrospective inference.” (Haggard, 2005)

“Voluntary acts are preceded by electrophysiological “readiness potentials” (RPs). With spontaneous acts involving no preplanning, the main negative RP shift begins at about -550 ms. Such RP’s were used to indicate the minimum onset times for the cerebral activity that precedes a fully endogenous voluntary act. The time of conscious intention to act was obtained from the subject’s recall of the spatial clock position of a revolving spot at the time of his initial awareness of intending or wanting to move (W). W occurred at about -200 ms. Control experiments, in which a skin stimulus was timed (S), helped evaluate each subject’s error in reporting the clock times for awareness of any perceived event. For spontaneous voluntary acts, RP onset preceded the uncorrected Ws by about 350 ms and the Ws corrected for S by about 400 ms. The direction of this difference was consistent and significant throughout, regardless of which of several measures of RP onset or W were used. It was concluded that cerebral initiation of a spontaneous voluntary act begins unconsciously. However, it was found that the final decision to act could still be consciously controlled during the 150 ms or so remaining after the specific conscious intention appears. Subjects can in fact “veto” motor performance during a 100-200-ms period before a prearranged time to act. The role of conscious will would be not to initiate a specific voluntary act but rather to select and control volitional outcome. It is proposed that conscious will can function in a permissive fashion, either 1:o permit or to prevent the motor implementation of the intention to act that arises unconsciously. Alternatively, there may be the need for a conscious activation or triggering, without which the final motor output would not follow the unconscious cerebral initiating and preparatory processes.” (Libet, 1985)

“Are we in command of our motor acts?  The popular belief holds that our conscious decisions are the direct causes of our actions. However, overwhelming evidence from neurosciences demonstrates that our actions are instead largely driven by brain processes that unfold outside of our consciousness.” (D’ostilio, Gaëtan, 2012)

Let’s link all this to stuttering and speaking

Firstly, let’s restate that speech is movement.  Therefore the above information applies to speech movements (Deecke, Engel, Lang, & Kornhuber, 1986).  Prior to a person speaking or even becoming aware of their intention to speak (which means moving lips, jaw, vocal folds etc.), their neurological system has begun prepping their nervous system to perform these speech movements.

To make concepts easier to explain as we continue, let’s define some terminology.  The term for the motor activity in the nervous system that precedes a person’s intention to move is called the Bereitschaftspotential, or readiness potential.  Readiness potential is more intuitive in its meaning, so I will be using that term in this post.  (Note: Some research articles I cite use the term Bereitschaftspotential.  Just know this the same thing as readiness potential.)

To further clarify what a readiness potential is let me briefly explain the sequence of events that takes place when a person moves a muscle (this applies to speech because speech is movement).  550 milliseconds (half second) to about 2000 milliseconds (2 seconds) prior to a muscle being moved there is a readiness potential (what I just talked about above) present in the brain and nervous system of the individual who is about to move the muscle (Deecke, Engel, Lang, & Kornhuber, 1986)(Libet, 1985).  100-200 milliseconds before the person moves they become aware of their intention to move (Libet, 1985).  At “zero” seconds the muscle is moved.  Stated simply, this is the order of events of a movement:  1. Unconscious readiness potential to move; 2. Conscious awareness of intention to move; 3. Movement.

As is probably getting redundant now, speech is movement.  However, just to be sure that readiness potentials do indeed precede speech movements, I investigated it.  In a research study in 1986, it was determined that they do.  It states “The Bereitschaftspotential (BP) or readiness potential started already 2 s prior to the onset of speaking and was present over either hemisphere.” (Deecke, Engel, Lang, & Kornhuber, 1986)  So two seconds prior to a person performing speech movements, the unconscious has generated readiness potentials in the neurological system to perform speech movements.

Combining the Macro with the Micro

As explained in the macro version, people who stutter begin to notice involuntary disruptions in their speech.  They notice people’s reactions to it.  This experience is unpleasant.  As a result, the person who stutters begins monitoring and trying to control their speech more intensely to avoid the unpleasant experience of blocking or stuttering.  This cyclical process repeats and strengthens over time to the point that conscious awareness of one’s speech and the intense monitoring of one’s speech is common practice for the person who stutters when they speak.

Sidenote: It is quite normal for a person to increase awareness to something that is causing unpleasant experiences.  It is understandable that the person who stutters begins focusing on speech when they notice disruptions.  However, it likely works to increase stuttering.

When a person who stutters speaks, the shining light of consciousness glares with intensity at every part of the speech process.  This intense use of consciousness is disruptive to the natural speech process I have outlined in the micro version.  The conscious awareness of speech is heightened at every moment of a speaking interaction for a person who stutters.  Often, focus on speech begins well before the interaction even begins.  There is rehearsal on what to say.  There is thought about if you will stutter on what you will say.  Then leading up to saying words, there is thought about if you will block on it.  There is focus on the sound and the speech apparatus to make sure it is not blocking. One is monitoring for blocks the entire time they are speaking and so on.

As outlined in the micro version, the unconscious mind will begin preparing you for speech movements before you are even aware which speech movements you are going to make.  The neurological process responsible for speech movement begins 300 milliseconds to 1700 milliseconds before a person is even aware they are going to make those movements.  Inserting extreme levels of attention and consciousness during the unconscious preparation period for movement can interfere with this natural process.  If the unconscious mind is preparing movements for you to speak and simultaneously you are using your conscious mind to watch every part of the speech process and even to consciously select words and consciously operate the speech mechanism, then this is using a process of speaking that is deviant from the standard process.

Not only is the conscious mind active and trying to control speech during unconscious readiness potentials in the person who stutters, but consciousness of speech and consciousness of what to say likely even precedes the onset of these unconscious readiness potentials.  Like I said, readiness potentials in the mind (which are the unconscious preparing a person to move/speak), are present 300 milliseconds to 1700 milliseconds before the individual is even aware of what they will say or that they will move their speech apparatus (speak) in the first place.  The person who stutters is often thinking about speech and focusing on the speaking process before these unconscious readiness potentials even become present.

I assert that the insertion of consciousness into many facets of the speech process and the implementation of the conscious control of speech prior to unconscious readiness potentials or during unconscious readiness potentials interferes with natural neurological processes which enable speech production, resulting in increased blocking and stuttering.

A Significant Finding

I am not sure why the finding I am about to explain has not generated more theory on stuttering or has not been used in the design of stuttering treatments.  It may be that you have to be viewing stuttering from certain vantage points to determine that the results of some studies are significant.  Possibly, this is why I find this result to be quite significant (because of my vantage point on stuttering) but others mustn’t have (they have differing vantage points) as it has not resulted in the spurring on of theory nor treatment ideas.

Walla, Mayer, Deecke, and Thurner conducted a study in 2004 investigating neurological activity leading up to speech in people who stutter and in controls (people who don’t stutter).  Neurological activity leading up to speech in people who stutter was significantly different than in people who don’t stutter.

To measure this, they had people who stutter and people who do not stutter perform speech activities while they monitored brain activity.  As part of the experiment, the experimenters presented a word on a screen in typed format to the subjects (included people who stutter and people who do not stutter).  The subjects of the experiment were to say the word upon seeing it.  In people who stutter, there was little if any neurological activity in the brain leading up to saying the word.  There was no readiness potential.  In fluent speakers, there was a significant amount of neurological activity leading up to when they said the presented word.  Fluent speakers had readiness potentials.

In restating this, the unconscious preparatory activity (readiness potential) for movement was not present in the people who stutter prior to speaking.  This is deviant from the standard process for movement including speech movements.  In fluent speakers however, neurological preparatory activity (readiness potential) was present leading up to the overt production of the word (speaking out loud).

In supporting the summary I just gave, Walla, Mayer, Deecke, & Thurner (2004) state, “The motivation of this work was to investigate stuttering—a disorder of speech motor control—in the light of preparatory neural activity of voluntary movements related to speech. To this end, brain activity was recorded with a whole cortex magnetoencephalograph (MEG) in developmental stutterers and nonstutterers while three different tasks of single-word reading were performed. Visually presented words had to be silently read immediately after word presentation (condition 1), spoken aloud immediately after word presentation (condition 2), or spoken aloud after a delay of 1.3 s as indicated by a second visual stimulus (condition 3). Condition 2 clearly showed marked neurophysiological differences between stutterers and nonstutterers. Only nonstutterers showed clear neural activity before speech onset, which is interpreted as being linked to visual word presentation and to reflect focused verbal anticipation. This prespeech activity might reflect the ‘‘Bereitschaftsfeld2’’ (BF2) that is the later component of the ‘‘Bereitschaftsfeld’’, a well-known preparatory activity described for many other voluntary movements. Our results strongly link the lack of such preparatory brain activity at the single-word level to the disability of fluent speech in stutterers. The present results strongly support the notion that stuttering is related to impaired focused attention or anticipation.”

In their conclusion, Walla, Mayer, Deecke, & Thurner (2004) state, “We found evidence that speaking aloud visually presented words is associated with certain brain activity at or close to the motor cortex on the left hemisphere in nonstutterers but not in developmental stutterers. This brain activity is interpreted as reflecting focused verbal anticipation. Although stutterers were not impaired in speaking aloud the visually presented single words, the lack of any such activity is interpreted as causing dysfluent speech in stutterers in general. This interpretation is because fluent speech is more complex than speaking aloud single words. The present results can be seen as supporting the idea of stuttering to be related to impaired focused attention or anticipation with respect to verbal information processing.”

The results of this study of course are open to interpretation.  This finding could stretch beyond the case I have made for the role of unconscious readiness potentials in the production of speech and stuttering.  I believe that is quite possible.  However, it is reasonable to infer that excessive levels of conscious monitoring of speech and the excessive implementation of conscious control over speech by people who stutter play a role in the lack of unconscious readiness potentials leading up to overt speech.

Final Word

Most would agree that as a result of stuttering/disfluencies, the person who stutters begins placing a significant amount of focus on speech.  This focus on speech far exceeds a fluent speaker’s level of focus on speech.  The person who stutters begins trying to control speech in an effort to “not stutter” or “not block” as a result of past situations where control of speech was lost, which resulted in unpleasant experiences.  This begins a cycle that reinforces itself.  This cycle increases conscious awareness of speech and increases the desire to control one’s speech.  I assert that this significantly heightened awareness of speech and the attempts to consciously control it by the person who stutters interfere with the unconscious’ important role in the production of speech movements which includes the generation of readiness potentials that precede speech.  This results in increased stuttering and blocking.

More related to this topic:

Some academics are focused on the basal ganglia as a causal source for stuttering.  Often, the philosophy is that the strength of signals to perform speech movements are too weak in people who stutter.  As a result these speech signals get filtered out and not performed.  Is this weakness due to insufficient readiness potentials leading up to speech?

I would like to see a study conducted with people who stutter performing metronome speech while monitoring brain activity for readiness potentials.  I hypothesize that fluent metronome speech in people who stutter may be explained by the person who stutters having an exact moment at which they are to speak and therefore they anticipate this exact moment to speak and unconscious readiness potentials build up to that moment allowing fluent speech.

People who stutter often report that they can feel that they will stutter before they do.  Is this because they can sense that readiness potentials prior to the act of speaking have not built up sufficiently to produce speech?

One of the very reasons automatic abilities exist is so the human can perform these abilities while focusing on other things.  Therefore, placing a large amount of focus on speech while speaking runs counter to its nature as an automatic ability.

People who stutter often monitor for blocks and barely even notice when their speech flows.  It is better to focus on the flow of your speech.  A person who is fluent expects their speech to flow.  They expect their speech to match up with what they are expecting to say.  Their awareness to a speech error or disfluency only gets heightened when it happens.

Bibliographical Information

Libet, Benjamin. “Unconscious Cerebral Initiative and the Role of Conscious Will in Voluntary Action.” Behavioral and Brain Sciences 8.04 (1985): 529.

D’ostilio, Kevin, and Gaëtan Garraux. “Brain Mechanisms Underlying Automatic and Unconscious Control of Motor Action.” Frontiers in Human Neuroscience. 6 (2012).

Haggard, Patrick. “Conscious Intention and Motor Cognition.” Trends in Cognitive Sciences 9.6 (2005): 290-95.

Walla, Peter, Dagmar Mayer, Lüder Deecke, and Stefan Thurner. “The Lack of Focused Anticipation of Verbal Information in Stutterers: A Magnetoencephalographic Study.” NeuroImage 22.3 (2004): 1321-327.

Deecke, L., Marion Engel, W. Lang, and H.h. Kornhuber. “Bereitschaftspotential Preceding Speech after Holding Breath.” Experimental Brain Research 65.1 (1986).


3 thoughts on “Stuttering & Automatic Speech: An In-Depth Look At The Unconscious’ Role In Speech Movements & Stuttering


    On Mon, May 16, 2016 at 10:35 AM, Understanding Dysfluency wrote:

    > Matthew O’Malley posted: “Synopsis: Speech is movement. The process for > speech movements (and all movements) begins unconsciously prior to the > individual even becoming aware of their own intention to speak. Speech is > an automatic ability largely controlled by the unconscious mi” >

    Liked by 1 person

  2. Hi Mathew, I think your post is pretty spot on. Stuttering is a behaviour precipitated by false sensory percetions and disruptive brain messages. If you are not already familiar with the work and writings of the following pioneers of neuroplasicity and the mind body relationship, I can only strongly suggest you seek them out. Matthias Alexander and Moshe Feldenkrais. More recently there is the work of Psychaitrist Jeffrey Schwartz and his book “You are not your Brain”.
    I do believe it is going to take more than the SLP profession to solve the riddle of stuttering so keep up the good work.
    Steve Clarkson

    Liked by 1 person

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