Adachi Shinobu, Morikawa Koji, Kato Yumiko O, Ozawa Jun, Nittono Hiroshi
Advanced Technology Research Laboratories, Panasonic Corporation, Kyoto, Japan.
Annu Int Conf IEEE Eng Med Biol Soc. 2012;2012:2108-11. doi: 10.1109/EMBC.2012.6346376.
Determining the loudest sound level that a person can comfortably tolerate (uncomfortable loudness level: UCL) imposes a strain on people suffering from hearing loss. In the present study, we propose a method of estimating UCL based on auditory evoked potentials (AEPs). Adults with normal hearing (18 men aged 25-56 years) participated in the study. Three tone bursts (S1, S2 and S3; a triplet) of the same frequency (either 1k, 2k or 4k Hz) were presented to the right or left ear with an interstimulus interval of 300 ms. The sound intensity decreased gradually by 5 dB HL from 80 dB (S1) to 70 dB HL (S3). The interval between triplets was 450 ± 50 ms. The frequency of a given triplet differed from the frequency of the preceding triplet. An electroencephalogram was recorded from three scalp electrode sites (Cz, C3, and C4) with the right mastoid reference. The 900-ms period after the onset of the triplet was transformed to a wavelet coefficient and averaged separately by stimulated ear and tone frequency. The UCLs were estimated by linear discriminant analysis on the basis of trained data of the other participants' subjective UCLs and the wavelet coefficients. The mean estimation error was 4.9 ± 5.0 dB. This result suggests that the UCLs could be estimated successfully on the basis of AEPs to triplets of auditory tones.
确定一个人能够舒适耐受的最大声级（不适响度级：UCL）会给听力损失患者带来负担。在本研究中，我们提出了一种基于听觉诱发电位（AEP）估计UCL的方法。听力正常的成年人（18名年龄在25 - 56岁之间的男性）参与了该研究。向右耳或左耳呈现三个相同频率（1kHz、2kHz或4kHz中的一种）的短音突发（S1、S2和S3；一个三联音），刺激间隔为300毫秒。声强从80dB HL（S1）开始以5dB HL的幅度逐渐降低至70dB HL（S3）。三联音之间的间隔为450±50毫秒。给定三联音的频率与前一个三联音的频率不同。使用右乳突作为参考，从头皮上的三个电极位点（Cz、C3和C4）记录脑电图。将三联音开始后900毫秒的时间段转换为小波系数，并分别按受刺激的耳朵和音调频率进行平均。基于其他参与者主观UCL的训练数据和小波系数，通过线性判别分析估计UCL。平均估计误差为4.9±5.0dB。该结果表明，可以基于对听觉音调三联音的AEP成功估计UCL。
