NIAS, Department of Electrical Engineering, Federal University of Viçosa, Viçosa, MG, Brazil; Graduate Program in Electrical Engineering, Federal University of São João del Rei, São João del Rei, MG, Brazil.
NIAS, Department of Electrical Engineering, Federal University of Viçosa, Viçosa, MG, Brazil; Graduate Program in Electrical Engineering, Federal University of São João del Rei, São João del Rei, MG, Brazil.
Comput Methods Programs Biomed. 2018 Jun;159:71-76. doi: 10.1016/j.cmpb.2018.01.031. Epub 2018 Mar 6.
The use of objective detection techniques applied to the auditory steady-state responses (ASSRs) for the assessment of auditory thresholds has been investigated over the years. The idea consists in setting up the audiometric profile without subjective inference from patients and evaluators. The challenge encountered is to reduce the detection time of auditory thresholds reaching high correlation coefficients between the objective and the conventional thresholds, as well as reducing difference between thresholds.
This paper evaluated the use of the Multiple Magnitude-Squared Coherence (MMSC) in Auditory Steady-State Responses (ASSRs) evoked by amplitude modulated tones around 40 Hz, attaining objective audiograms, which were, later, compared to conventional audiograms. It was proposed an analysis of the electroencephalogram signals of ten subjects, monaurally stimulated, in the intensities 15, 20, 25, 30, 40 and 50 dB SPL, for carrier frequencies of 0.5, 1, 2 and 4 kHz. After the detection protocol parameters variation, two detectors were selected according to behavioral thresholds.
The method of this study resulted in a Maximum detector with correlation coefficient r = 0.9262, mean difference between the objective and behavioral thresholds of 6.44 dB SPL, average detection time per ear of 49.96 min and per stimulus of 2.08 min. Meanwhile, the Fast detector presented coefficient r = 0.8401, mean difference of 6.81 dB SPL, average detection time of 28.20 min per ear and 1.18 per stimulus.
The results of this study indicate that the MMSC use in the auditory responses detection might provide a reliable and efficient estimation of auditory thresholds.
多年来，人们一直在研究将客观检测技术应用于听觉稳态响应（ASSR）以评估听觉阈值。其理念是在不依赖患者和评估者主观推断的情况下建立听力图。所面临的挑战是减少听觉阈值的检测时间，同时保持客观阈值与传统阈值之间的高相关系数，以及减少阈值之间的差异。
本文评估了在 40Hz 左右的调幅音诱发的听觉稳态反应（ASSR）中使用多重幅度平方相干性（MMSC）来获得客观听力图的方法，随后将其与传统听力图进行比较。提出了对 10 名受试者的单耳刺激的脑电图信号进行分析，刺激强度为 15、20、25、30、40 和 50dB SPL，载波频率为 0.5、1、2 和 4kHz。在检测协议参数变化后，根据行为阈值选择了两种检测器。
本研究方法得出了一个最大检测器，相关系数 r=0.9262，客观阈值与行为阈值之间的平均差异为 6.44dB SPL，每只耳朵的平均检测时间为 49.96 分钟，每个刺激的平均检测时间为 2.08 分钟。同时，快速检测器的系数 r=0.8401，平均差异为 6.81dB SPL，每只耳朵的平均检测时间为 28.20 分钟，每个刺激的平均检测时间为 1.18 分钟。
本研究结果表明，MMSC 在听觉反应检测中的应用可能提供一种可靠且高效的听觉阈值估计方法。
