1. The effect of speech timing on velopharyngeal function
Student Investigator: Megan Griggs
Faculty Supervisor: David Jones, PhD

2. Speech Respiration (Breathing) Phonation (Vocal cord vibration)
Articulation (Movement of oral and pharyngeal structures)

3. Velopharyngeal Mechanism

4. Previous Research: Speech Rate
When speech rate is increased, articulatory movements demonstrate one of two strategies:
Decrease in duration of articulatory movements (moving faster) (Kent et al, 1974 ; Gay, 1978)
Articulators move a reduced distance (decreased displacement to-and-from target) (Lindblom, 1963)

5. Previous Research (cont.)
Kuehn (1976)
Studied velar movement as a function of increased speaking rate
Velum either moved faster or shorter distances

6. Previous Research (cont.)
Limitation of Kuehn study
Only soft palate movement was measured, not the opening and closing of the velopharyngeal port
The velopharyngeal mechanism moves in a sphincteric fashion
Lateral View
Superior View of Velopharyngeal Port

7. Purpose
To study the effect of speech timing on the opening and closing of the velopharyngeal port in individuals with normal anatomy and normal speech.

8. Hypothesis As speech rate is increased, speakers will either:
a) close the velopharyngeal port faster, or
reduce the range of velopharyngeal port opening
The findings may have implications for speakers with abnormal palatal structures

9. Subjects Five males and five females Mean Age: 22 years
American English speakers
No history of speech disorders
Perceived as exhibiting normal speech

10. Instrumentation Nasal airflow Nasal pressure Oral pressure Microphone
All signals digitized at 1000Hz

11. Speech Sample Phrase “we were a pamper away” 2 Speech Conditions
Conversational speech rate
“Fast” speaking rate
Target word: “pamper”
Rate conditions randomized
Generalization

12. Procedure Speech phrases were modeled ~15 repetitions produced
Corrections during data collection
10 tokens were measured at each rate

13. P ER P M A

14. Key Data Calculations Velopharyngel Port Area
Maximum Flow Declination Rate (MFDR)
Velocity of velopharyngeal closure

15. Velopharyngeal Port Area
p a m p er
Velopharyngeal Port Area
Warren & DuBois (1964)
Open less with increased rate?

16. Declination Rate (MFDR)
p a m p er
VP Port
Closing
Max Flow
Declination Rate (MFDR) . .
MFDR = (dV/dt)peak/Vpeak
** *
Dotevall (2000)
Closed faster with increased rate?

17. Results

18. Hypothesis As speech rate is increased, speakers will either:
a) close the velopharyngeal port faster, or
reduce the range of velopharyngeal port opening

19. Speakers 1, 3, 4, 5, 6, 9, 10 (7/10) increased velopharyngeal port closing velocity with increased speaking rate

20. Speakers 3, 4, 5, 9 (4/10) decreased velopharyngeal displacement with increased speaking rate

21. Discussion
The majority of the speakers (7/10) closed the velopharyngeal port with increased velocity as rate increased
4/10 speakers opened their velopharyngeal ports to a lesser extent (decreased displacement)
These 4 speakers also moved faster
None of the speakers decreased velopharyngeal displacement exclusively

22. Discussion Speakers 2, 7, and 8:
Speech timing for “pamper” did not change significantly from Conversational Rate to Fast Rate
These speakers decreased speech timing in other aspects of the utterance

23. Conclusion
Some speakers may use both strategies to accommodate faster speech rate
Move the velopharyngeal structures faster
Move the velopharyngeal structures a reduced distance
Some speakers simply move faster
Do speakers reduce displacement of velopharyngeal structures exclusively?

24. Bilateral Cleft Lip and Palate
Implications
Nasal Septum
Nasal Cavity
Bilateral Cleft Lip and Palate

25. Post Palate Repair Structural Limitations Palatal Scar Tissue
Reduced Palatal Length
Inadequate Palatal Muscle Bulk

26. Velopharyngeal Insufficiency
Normal
Velopharyngeal Closure

27. Velopharyngeal Mechanism in Speakers with Cleft Palate
Normal velopharyngeal function (75%)
Velopharyngeal insufficiency
Hypernasal speech – More surgery
“Borderline” velopharyngeal function
Mild, inconsistent nasalization

28. “Borderline” velopharyngeal function: looking forward
How does “borderline” velopharyngeal function change as a result of speech timing?
Are there therapy approaches that would help address negative affects of speech timing?

29. References
Gay, T. (1978). Effect of speaking rate on vowel formant movements. The Journal of the Acoustical Society of America, 63(1), 223. doi: /
Lindblom, B. (1963). Spectrographic Study of Vowel Reduction. The Journal of the Acoustical Society of America, 35(11), doi: /
Kent, R. D., & Moll, K. L. (1972). Cinefluorographic Analyses of Selected Lingual Consonants. Journal of Speech Language and Hearing Research, 15(3), 453. doi: /jshr
Kuehn, D. P. (1976). A cineradiographic investigation of velar movement variables in two normals
Warren, D. W., & DuBois, A. B. (19964). A pressure-flow technique for measuring velopharyngeal orifice area during continuous speech

30. Questions?

31. Speakers 1, 2, 3, 5, 6, 8, 9, 10 opened velop port for shorter duration with increased speaking rate