Q: What is the purpose of stimulating the Tongue Bowl Reflex (TBR)? Isn’t a reflex passive movement? What are we trying to achieve when using a reflex like this?

I have chosen to answer your question with material from my next book, The Marshalla Guide to 21^st Century Articulation Therapy.  The following is abstracted from my chapter called “The Speech Reflexes: Stimulating Automatic Speech Movements”:

Theory

Reflexes are considered the first movements in the process of human movement development.  Speech is movement, therefore reflexes can be considered the first movements in the line of speech movement development. It has been proposed that reflexes form the basis of all voluntary movements. Samuel Fletcher said it like this ––

“Primitive reflexes … could provide a foundation for speech articulation motor patterns …  The inborn patterns thus provide a substrata for developing and refining controlled movement patterns in mature body gestures …  Rhythmical, temporary, and spatially patterned movement sequences are then built on this firm foundation” (Fletcher, 1992, p. 10, 14-15).

The reflexes might be viewed like this:  The reflex functions as the initial neurological pathway of movement.  The reflex assures that the correct motor pathways for life are set up and maintained during the time when the infant can do nothing for himself.  Once set, the pathways then are used to direct the neurological impulses of voluntary movement as the child grows and matures.  So the reflex itself does not create or evolve into the voluntary movement, but rather the voluntary movement uses the neurological path or roadway that is set up by the reflex.

How to Use the Reflex

The process of using a reflex to facilitate new movement is simple:  One stimulates the reflex and then uses the resultant new movement pattern in a purposeful way.  In our example, the TBR is stimulated, and then the client is taught to notice the resultant motor response –– the bowling or grooving of the tongue.  He is taught to imitate the motor response, to take control of it, and then use it for a purpose –– to groove the tongue for a sibilant.

A New-Fangled Idea?

Reflexes were not discussed in traditional books on articulation therapy because the concept of the reflex was unknown.  However, many authors of old articulation therapy textbooks mentioned using reflexes without even knowing what they were.  I have found many examples of this in my reading of older textbooks.  Here is one example:

E. W. Scripture was one of the first to bring articulation therapy methods to the United States from Germany, and Van Riper referenced his material often.  Scripture did not use the term reflex in his writing, but he mentioned the tendency for the tongue to respond in certain ways when touched in specific ways.  He used the term “irritation” to refer to the stimulation of a reflex, and he said that the irritation “makes” the client’s tongue respond in certain ways.

For example, in his section about stimulating the tongue to form a central groove for /s/, Scripture wrote the following:  “The cure is often brought about by using a probe or a stick [to touch the middle of the tongue]; the irritation makes the patient narrow the channel” (Scripture, 1912, p. 134).  Scripture was referring to what we now call the Tongue Bowl Reflex.

References

• Fletcher, S. G. (1992) Articulation: A Physiological Approach. San Diego: Singular.
• Marshalla, P. (Unpublished manuscript) The Marshalla Guide to 21^st Century Articulation Therapy. Mill Creek: Marshalla Speech and Language. [Scheduled for publication in 2012]
• Scripture, E. W. (1912) Stuttering and Lisping. NY: Macmillan.
• Van Riper, C. (1939) Speech Correction: Principles and Methods. Englewood Cliffs: Prentice-Hall.