Brigham Young University, Provo, UT, USA.
J Speech Lang Hear Res. 2012 Oct;55(5):1395-406. doi: 10.1044/1092-4388(2012/11-0153). Epub 2012 Jan 23.
The purpose of this study was to create synthetic vocal fold models with nonlinear stress-strain properties and to investigate the effect of linear versus nonlinear material properties on fundamental frequency (F0) during anterior-posterior stretching.
Three materially linear and 3 materially nonlinear models were created and stretched up to 10 mm in 1-mm increments. Phonation onset pressure (Pon) and F0 at Pon were recorded for each length. Measurements were repeated as the models were relaxed in 1-mm increments back to their resting lengths, and tensile tests were conducted to determine the stress-strain responses of linear versus nonlinear models.
Nonlinear models demonstrated a more substantial frequency response than did linear models and a more predictable pattern of F0 increase with respect to increasing length (although range was inconsistent across models). Pon generally increased with increasing vocal fold length for nonlinear models, whereas for linear models, Pon decreased with increasing length.
Nonlinear synthetic models appear to more accurately represent the human vocal folds than do linear models, especially with respect to F0 response.
本研究旨在创建具有非线性应力-应变特性的合成声带模型,并研究在前后拉伸过程中线性与非线性材料特性对基频(F0)的影响。
创建了 3 个材料线性和 3 个材料非线性模型,并以 1mm 的增量拉伸至 10mm。记录了每个长度的起始发音压(Pon)和 Pon 时的 F0。当模型以 1mm 的增量松弛回其静息长度时,重复测量,并进行拉伸测试以确定线性与非线性模型的应力-应变响应。
非线性模型表现出比线性模型更大的频率响应,并且与长度增加相关的 F0 增加模式更具可预测性(尽管在不同模型之间范围不一致)。对于非线性模型,Pon 通常随声带长度的增加而增加,而对于线性模型,Pon 随长度的增加而减小。
非线性合成模型似乎比线性模型更能准确地代表人类声带,特别是在 F0 响应方面。