鼻化元音的频谱特点与过高鼻音主观判听的相关关系研究

The Correlation Between Spectrum Manifestations of Nasalized Vowels and Listener Judgments of Hypernasality

目的通过建立声学观察指标,研究鼻化元音频谱表现和过高鼻音主观判听的相关关系,从而评价声学分析技术在腭裂语音评价中的可靠性。方法腭裂儿童98例,年龄5～12岁,平均8.30岁。单侧完全性腭裂51例,双侧完全性腭裂10例,不完全性腭裂37例。由3名从事腭裂语音研究多年的临床医师,对患者的录音进行鼻音程度判听。将患者按鼻音的严重程度分为无、轻度、中度、重度过高鼻音4组。应用Spearman相关分析统计方法,对元音/i/鼻腔共振指数NRI-i、元音/a/鼻腔共振指数NRI-a、元音/a/的能量衰减指数EDI-a与过高鼻音主观判听分数的相关关系进行统计学分析。结果元音/i/的鼻腔共振指数与过高鼻音程度呈高度正相关,相关系数r=0.85(P<0.001);元音/a/的鼻腔共振指数与过高鼻音程度呈中度负相关,相关系数r=-0.65(P<0.001);元音/a/的能量衰减指数与过高鼻音程度亦为中度负相关,相关系数r=-0.48(P<0.001)。结论鼻化元音频谱表现与过高鼻音主观判听结果有良好的相关性,过高鼻音的存在与否,与元音/i/频谱上有无额外峰的出现以及与元音/a/频谱上Fn和F1能量的相对大小关系紧密;元音频谱上鼻音共振峰能量越强,鼻音化程度越重;高频能量衰减越明显,鼻音化程度越重。鼻腔共振指数NRI和能量衰减指数(EDI)是有效的观察指标。

Objective The correlation between spectrum manifestations and listener judgments of hypernasality was stud-ied in the present research.Methods The severity of hypernasality of98cleft patients was judged by3experienced clini-cians in speech pathology according to5interval scales.The spectrum features of nasalized vowels were manifested through two index of nasal resonance index(NRI)and energy damping index(EDI)of vowel/a/and/i/,which were set up in our prior researches.Results Spearmen correlation coefficients were computed and revealed a comparable level of cor-relation among the measures of NRI-i,NRI-a,EDI-a,and ratings of nasality.These correlations were as follows:NRI-i and listener judgments0.85;NRI-a and listener judgments-0.65;EDI-a and listener judgments-0.48,which implied that patients with larger energy of extra formant or nasal formant in vowel spectrums,and with more serious damped high frequency energy of vowel,were judged to be more hypernasal.Hypernasality being judged or not,is closely related to the presence of extra formant in vowel/i/spectrum,and to the relative size of energy of F n and F 1 in vowel/a/spectrum