- 期刊
氣動式人工喉頭之音調控制
Pitch Control of the Pneumatic Artificial Larynx
摘要
背景：在台灣喉全切除的病人，大多使用氣動式人工喉頭作為術後言語之工具。臨床上有許多使用此種工具的病例，可以說出接近正常音調性之語言（tonal language），如國語（Mandarin）。顯然此工具發出聲音的基本頻率變化可以大致滿足國語四聲所需要之音調變化。使用氣動式人工喉的音調控制，只能透過呼出氣流通過橡皮膜片下壓力的大小來控制振動的基本頻率，本研究即在探討橡皮膜片振動頻率是否也像聲帶振動一樣受到橡皮膜片驅動壓力的影響，測量喉全切除患者在使用氣動式人工喉發聲時之橡皮膜片驅動壓力和聲音基本頻率，並探討此些病人在發聲時之音調控制的原理。 方法：以3名使用台灣型氣動式人工喉可說流利國語的男性患者為受測者，測量其發音時人工喉膜片驅動壓力和聲音基本頻率，以所得數據求出回歸直線及決定係數R²，得出二者之間的關係。 結果：3名受測者的人工喉膜片驅動壓力範圍從0.11kPa到1.32kPa，聲音基本頻率的範圍則從100Hz到195Hz，二者呈現正向直線關係，決定係數R²分別為0.8792；0.8845及0.8854。 結論：使用氣動式人工喉的喉全切除患者可以藉由改變說話時人工喉膜片驅動壓力的大小來控制聲音基本頻率的高低進而決定音調。而且膜片驅動壓力的大小變化所產生聲音基本頻率的高低足以應付國語四聲中所需基本頻率變化的範圍。
並列摘要
BACKGROUND: The pneumatic artificial larynx is widely used in Taiwan following total laryngectomies. By using this devise, most patients can speak understandable tonal languages, for example, Mandarin. The pneumatic artificial larynx allows rapid changes of fundamental frequency (F0) in vowels, which are a typical acoustical feature of tonal languages. In this study, we hoped to clarify the mechanisms of pitch control in the pneumatic artificial larynx. METHODS: Three fluent Mandarin speakers using pneumatic artificial larynx devices were studied following total laryngectomies. They were asked to produce sounds in different pitches by following scales upward and downward. The sound and rubber membrane driving pressure were recorded at the same time. The data pairs for each F0 and rubber membrane driving pressure (Pd) were then analyzed using linear regression. RESULTS: The data showed that F0 increased linearly with Pd. The change in F0 with Pd ranged from 76.1 to 111.9 Hz/kPa. The ranges of Pd and F0 were 0.11 to 1.32 kPa and 100 to 195 Hz respectively. CONCLUSIONS: The pitches of sound produced in the pneumatic artificial larynx were influenced by the Pd. The pitch range produced in the pneumatic artificial larynx by changing Pd satisfies the requirements for the tonal feature of Mandarin.