Department of Communication Science and Disorders, University of Pittsburgh, PA.
J Speech Lang Hear Res. 2018 Jul 13;61(7):1525-1543. doi: 10.1044/2018_JSLHR-S-17-0153.
Research suggests that abnormal levels of intrinsic laryngeal muscle (ILM) contraction is a potential causal factor in stress-induced voice disorders. This study seeks to characterize the ILM stress response in a cohort of vocally healthy women.
The authors used an unblinded, nonrandomized, repeated-measures design. Forty vocally healthy female adults were subjected to a stressful speech preparation task. Measurements of heart rate, blood pressure, trapezius muscle (positive control) activation, and tibialis muscle (negative control) activation were obtained from 37 participants before and during stressor exposure, in a nonvoice and nonspeaking task paradigm, to confirm physiological stress response compared to baseline. Fine wire electromyography of the ILMs (posterior cricoarytenoid, thyroarytenoid/lateral cricoarytenoid muscle complex, and cricothyroid) was performed simultaneously so that the activity of these muscles could be measured prior to and during stressor exposure.
The protocol successfully elicited the typical and expected physiological stress responses. Findings supported the hypothesis that, in some individuals, the ILMs significantly increase in activity during stress reactions compared to baseline, as do the control muscles.
This study characterizes ILM responses to psychological stress in vocally healthy participants. Some of the female adults in this study appeared to be "laryngeal stress responders," as evidenced by increased activity of the ILMs during a silent (i.e., nonvocal, nonspeech) speech preparation task that they considered to be stressful.
研究表明，内在喉肌（ILM）收缩的异常水平可能是应激性嗓音障碍的潜在因果因素。本研究旨在描述一组嗓音正常女性的 ILM 应激反应。
作者采用非盲、非随机、重复测量设计。40 名嗓音正常的成年女性接受了一项有压力的演讲准备任务。在非发声和非言语任务范式中，从 37 名参与者中获得心率、血压、斜方肌（阳性对照）激活和胫骨前肌（阴性对照）激活的测量值，以确认与基线相比的生理应激反应。同时进行 ILM（环杓后肌、杓状软骨/环杓侧肌复合体和环甲肌）的细金属丝肌电图，以便在应激物暴露之前和期间测量这些肌肉的活动。
该方案成功地引发了典型和预期的生理应激反应。研究结果支持了这样一种假设，即在某些个体中，与基线相比，ILM 在应激反应期间的活动显著增加，与对照肌肉一样。
本研究描述了健康参与者的 ILM 对心理应激的反应。本研究中的一些成年女性似乎是“喉应激反应者”，这表现在她们在一项被认为有压力的无声（即非发声、非言语）演讲准备任务中，ILM 的活动增加。
