Q: What is the difference between lingual-palatal suction and tongue-tip elevation? I have a student with cerebral palsy who can do suctioning but not tip elevation. Can you tell me why?

There is a significant difference between lingua-palatal suctioning and tongue-tip elevation. To understand these subtle differences in tongue movement means to have studied feeding development (ala Morris and Klein, 2000).

Tongue-tip elevation is accomplished by elevating the tongue-tip actively upward to the alveolar ridge. It requires the tongue to be functioning completely separately from the jaw. It also requires the tongue-tip to be completely differentiated from the body of the tongue. This is an advanced tongue movement.

Lingua-palatal suctioning, on the other hand, is accomplished without any active tongue movement. It is accomplished by lifting the jaw upward so that the whole tongue presses upward against the palate. Then the jaw lowers while the tongue remains stuck to the palate. The tongue remains stuck to the palate because of negative pressure (suctioning) created if the tongue is sealed against the palate because of the natural stickiness of saliva. After sticking to and suctioning against the palate, the tongue then “flops” downward as the jaw lowers. In other words, the lowering jaw pulls the tongue down away from the palate. In the feeding literature, this flop downward is called a “tongue-lag.”

Lingua-palatal suctioning therefore requires no independent tongue movement. In fact, the tongue does not have to move at all to accomplish this movement — even a paralyzed tongue can be moved in this way if the jaw moves up-down and if there is sufficient moisture inside the mouth. The tongue-lag is a primitive movement pattern that is controlled by upward and then downward movement of the jaw. In feeding, the tongue-lag is considered the first way in which the tongue’s movements begin to separate from the jaw’s movements. In feeding, this tongue-lag is accomplished silently.

It is logical that a client with a neuromuscular disorder can do lingua-palatal suctioning but not true tongue-tip elevation. True tongue-tip elevation is a much more advanced oral movement than L-P suction. Jaw movements always precede tongue movements in development.

In the traditional articulation therapy, therapists often had clients learn to “click” the tongue as a “tongue exercise” for learning to elevate the tongue-tip independently for /l/ and other phonemes. Many of today’s professors call this a “non-speech-oral-motor exercise.” These detractors insist that clicking the tongue has nothing to do with speech, and they demand that SLP’s avoid these types of activities. But all the old-timers knew that engaging in primitive oral movements can facilitate the improvement of specific more refined speech movements. Van Riper said it like this:

“Learn to recognize the movement as part of some familiar biological movement such as chewing, swallowing, coughing, or others to be mentioned later. Practice these basic activities” (Van Riper, 1947, p. 169).

“In most of these cases [of cerebral palsy], the essential task is to free the tongue from its tendency to move only in conjunction with the lower jaw” (p. 408).

References

• Morris, S. E., & Klein, M. D. (2000, 1983). Pre-Feeding Skills: A Comprehensive Resource for Mealtime Development. Austin: Pro-Ed.
• Van Riper, C. (1947) Speech Correction: Principles and Methods. Englewood Cliffs: Prentice-Hall.