A Study About Acoustical Analysis Of Evaluating Hypernasality In Cleft-Palate Speech

1989 Fiscal Year Final Research Report Summary

• Project/Area Number: 62570897
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: 外科・放射線系歯学
• Research Institution: Osaka University
• Principal Investigator: FUKUDA Tomiko School of Dentistry, Osaka University, Assistant, 歯学部・附属病院, 助手 (90029984)
• Co-Investigator(Kenkyū-buntansha): TACHIMURA Takashi School of Dentistry, Osaka University, Lecturer, 歯学部・附属病院, 講師 (60188266)
• Project Period (FY): 1987 – 1988
• Keywords: Evaluation Of Hypernasality / Cleft-Palate Children / Acoustical Analysis / Rate of Nasal Oscillation / Voice Spedtrum of Vowel / i / Nasal-Oscillation Spectrum Of Vowel / i

Research Abstract

We selected 10 cleft-palate children aged 7-12, surgically operated but had velopharyngeal incompetency, and as a control group, 10 children with normal phonation of corresponding ages. We analyzed /i/ in cleft group, and /i/ and /i^^-/( preceded by /m/) in control group. The method was to get (1) frequency components of phonation, and (2) those of nasal oscillation. The quotient of (belivided by (2) meant the rate of oscillation. The phonation samples were also judged acoustically by three skilled clinicians. Comparing frequency rates and acoustic-psychological judgments, we examined these two methods. The results were as follows:
I. Voice spectrums of vowel /i/ in cleft-palate children were similar to those of the normal. Those of nasal oscillation, however, were different, and they were stronger than /i^^-/ in the normal.
II. Rates of nasal oscillations agreed highly with acoustic-psycological judgments. We concluded that rate of nasal oscillation was useful as a method of clinical evaluation of cleft-palate hypernasality. We hope to collect more appropriate samples to develop evaluation criteria.