German Institute of Hearing Aids, Lübeck, Germany.
Department of Psychology and Center of Brain, Behavior and Metabolism (CBBM), University of Lübeck, Lübeck, Deutschland.
Trends Hear. 2024 Jan-Dec;28:23312165241246597. doi: 10.1177/23312165241246597.
Hearing aids and other hearing devices should provide the user with a benefit, for example, compensate for effects of a hearing loss or cancel undesired sounds. However, wearing hearing devices can also have negative effects on perception, previously demonstrated mostly for spatial hearing, sound quality and the perception of the own voice. When hearing devices are set to transparency, that is, provide no gain and resemble open-ear listening as well as possible, these side effects can be studied in isolation. In the present work, we conducted a series of experiments that are concerned with the effect of transparent hearing devices on speech perception in a collocated speech-in-noise task. In such a situation, listening through a hearing device is not expected to have any negative effect, since both speech and noise undergo identical processing, such that the signal-to-noise ratio at ear is not altered and spatial effects are irrelevant. However, we found a consistent hearing device disadvantage for speech intelligibility and similar trends for rated listening effort. Several hypotheses for the possible origin for this disadvantage were tested by including several different devices, gain settings and stimulus levels. While effects of self-noise and nonlinear distortions were ruled out, the exact reason for a hearing device disadvantage on speech perception is still unclear. However, a significant relation to auditory model predictions demonstrate that the speech intelligibility disadvantage is related to sound quality, and is most probably caused by insufficient equalization, artifacts of frequency-dependent signal processing and processing delays.
助听器和其他听力设备应该为用户提供益处，例如补偿听力损失的影响或消除不需要的声音。然而，佩戴听力设备也会对感知产生负面影响，这在以前主要是针对空间听觉、声音质量和自身声音的感知。当听力设备设置为透明模式时，即提供无增益并尽可能类似于开放式聆听，这些副作用可以被单独研究。在本工作中，我们进行了一系列实验，研究透明听力设备对同置语音噪声任务中的语音感知的影响。在这种情况下，通过听力设备聆听不应产生任何负面影响，因为语音和噪声都经历相同的处理，因此耳朵处的信噪比不会改变，并且空间效应无关紧要。然而，我们发现透明听力设备对语音可懂度有一致的不利影响，并且对听力努力程度的评价也有类似的趋势。通过包括几种不同的设备、增益设置和刺激水平，我们测试了几种可能导致这种不利影响的假设。虽然排除了自噪声和非线性失真的影响，但听力设备对语音感知不利的确切原因仍不清楚。然而，与听觉模型预测的显著关系表明，语音可懂度的劣势与声音质量有关，很可能是由于均衡不足、频率相关信号处理的伪影和处理延迟引起的。
