Pressure-Flow Measurements for Selected Oral Sound Segments Produced by Normal Children and Adolescents: A Basis for Clinical Testing

Tongue-palate contact pressure, oral air pressure, and acoustics of clear speech

PURPOSE

The authors compared articulatory contact pressure (ACP), oral air pressure (Po), and speech acoustics for conversational versus clear speech. They also assessed the relationship of these measures to listener perception.

METHOD

Twelve adults with normal speech produced monosyllables in a phrase using conversational and clear speech. Target phonemes were /t, d, s, z, l, n/. ACP was measured at a point of articulatory contact; Po was sensed by a catheter open in the posterior oral cavity.

RESULTS

ACP was increased to a greater extent in clear speech for /t, d, z/. Po was increased to a greater extent for /t, d/. Acoustic changes also occurred in terms of segment durations, speaking rate, and CV dB ratio. Regression analysis indicated that segment duration was the strongest predictor of listener ratings of speech clarity, followed by an index of articulatory effort and speaking rate.

CONCLUSION

Articulatory effort, as indexed by ACP, Po, and CV dB ratio, was increased to varying degrees depending on the consonant. Greatest changes occurred for /t, d/. Durational measures at both the segment and the phrase level were also important for predicting listener ratings of speech clarity.

Oral Pressure and Nasal Flow on /m/ and /p/ in 3- to 5-Year-Old Children Without Cleft Palate

Objectives : (1) To compare oral pressure and nasal airflow in 3- to 5-year-olds versus older children and adults; (2) to describe stability of these measures in 3- to 5-year-olds at two recording times; and (3) to report participation rates of 3- to 5-year-olds for the aerodynamic protocol. Design : Prospective, nonrandomized, convenience samples in four age groups. Setting : University clinic. Participants : A total of 105 individuals without cleft palate and with normal speech for their age who were 3 to 5 (n  =  45), 7 to 9 (n  =  20), 11 to 13 (n  =  20), or 20 to 30 years old (n  =  20). All had normal nasal resonance and absence of nasally obstructive conditions on the testing day. Main Outcome Measures : Oral pressure and nasal airflow on /p/ and /m/ in syllable series and the word "hamper." Results : Oral pressure was significantly higher on /p/ for 3- to 5-year-olds versus the two oldest groups. Nasal airflow on /p/ occurred infrequently across groups. Oral pressure on /m/ was significantly higher for 3- to 5-year-olds versus adults. Nasal airflow on /m/ increased significantly with age. Oral pressure and nasal flow did not differ at two measurement times for the 3- to 5-year-olds. Of the 3- to 5-year-olds, 88% completed the protocol. Conclusions : Oral pressure decreased on /p/ and nasal airflow increased on /m/ from early childhood into adulthood. Nasal air escape on /p/ occurred rarely for speakers of any age; when it did occur, the magnitude was limited. Most preschool-aged children should be able to complete a velopharyngeal aerodynamic protocol, and measures are stable even for these young speakers.