老化对语音线索感知能力的影响

Effect of aging on speech perception with competing speech

目的探究老化是否是言语感知困难的独立因素,并明确老化对语音线索感知能力的影响模式。方法本研究招募了听力正常的青年组(n=10,平均年龄为24岁)和老年组(n=15,平均年龄为67岁)受试者,利用闭集中文短句(CMS)评估2组受试者在4种不同语音感知线索(“基线”条件、“基频”条件、“空间”条件、“基频+空间”条件)下的言语识别阈(SRT),通过对比4种条件下的SRT评估老化对基频线索和(或)空间线索的利用能力的影响。结果①RM-ANOVA分析显示,在“基线”、“基频”和“空间”条件下,老年组SRT均高于(差于)青年组(P值均<0.05),在“基频+空间”条件下,2组差异无统计学意义(P>0.05)。以听阈为协变量行协方差分析显示,老年组SRT在“空间”条件与青年组无显著差异(P>0.05)。②在“基频”、“空间”及“基频+空间”条件下,老年组掩蔽释放(MR)较青年组下降,但差异均无统计学意义(P值均>0.05)。结论老年人在复杂语境下的言语感知能力比青年人显著变差;但当语音同时具备基频和空间线索时,老年人仍可综合利用2种线索,从而达到与青年人相似的感知表现。排除听敏度的影响,老化显著削弱语音基频线索的感知能力,而对空间线索利用能力影响不显著。

Objective To explore whether aging is an independent factor in speech perception ability and to clarify the impact mode of aging on the ability to perceive speech cues.Methods This study recruited normal-hearing youth group(n=10,average age of 24 years)and elderly group(n=15,average age of 67 years).Closed-set mandarin speech(CMS)was used to evaluate the speech recognition thresholds(SRTs)of the two group sunder four different speech perception cues(“baseline”condition,“fundamental frequency”condition,“spatial”condition,and“fundamental frequency+spatial”condition).The effect of aging on the ability to utilize fundamental frequency cues and/or spatial cues was quantitatively assessed by comparing SRTs under the four conditions.Results RM-ANOVA showed that under the conditions of“baseline”,“fundamental frequency”and“spatial”,the SRTs of the elderly group were higher(worse)than those of the young group(All P<0.05).The difference between the two groups under the condition of“fundamental frequency+space”showed no statistical significance(P>0.05).When analysis was performed with hearing threshold as a covariate,there was no significant difference in SRT between the elderly group and the young group in the“spatial”condition(P>0.05).Under the conditions of“fundamental frequency”,“spatial”and“fundamental frequency+space”,the MRs of the elderly group decreased compared with the young group,but the difference was not statistically significant(P>0.05).Conclusions The speech perception ability of the elderly in complex contexts is significantly worse than that of the young people.However,when speech has both fundamental frequency and spatial cues,the elderly can still use the two cues comprehensively to achieve similar perceptual performance as young people.Excluding the effect of hearing acuity,aging significantly weakens the ability to perceive speech fundamental frequency cues,but has no significant effect on the ability to utilize spatial cues.