In patients with strong asymmetric hearing loss, standard clinical practice involves testing speech intelligibility in the ear with the higher hearing threshold by simultaneously presenting noise to the other ear. However, psychoacoustic and functional magnetic resonance imaging (fMRI) studies indicate that this approach may be problematic as contralateral noise has a disruptive effect on task processing. Furthermore, fMRI studies have revealed that the effect of contralateral noise on brain activity depends on the lateralization of task processing. The effect of contralateral noise is stronger when task-relevant stimuli are presented ipsilaterally to the hemisphere that is processing the task. In the present study, we tested the effect of four different levels of contralateral noise on speech intelligibility using the Oldenburg sentence test (OLSA). Cortical lateralization of speech processing was assessed upfront by using a visual speech test with fMRI. Contralateral OLSA noise of 65 or 80 dB SPL significantly reduced word intelligibility irrespective of which ear the speech was presented to. In participants with left-lateralized speech processing, 50 dB SPL contralateral OLSA noise led to a significant reduction in speech intelligibility when speech was presented to the left ear, i.e. when speech was presented ipsilaterally to the hemisphere that is mainly processing speech. Thus, contralateral noise, as used in standard clinical practice, not only prevents listeners from using the information in the better-hearing ear but may also have the unintended effect of hampering central processing of speech.

对于患有严重非对称性听力损失的患者，标准的临床实践包括通过同时向另一只耳朵发出噪音来测试听力阈值较高的耳朵中的语音清晰度。但是，心理声学和功能磁共振成像（fMRI）研究表明，这种方法可能存在问题，因为对侧噪声会对任务处理产生破坏性影响。此外，功能磁共振成像研究表明对侧噪声对大脑活动的影响取决于任务处理的侧向化。当与任务相关的刺激同侧呈现给正在处理任务的半球时，对侧噪声的效果会更强。在目前的研究中，我们使用奥尔登堡句子测试（OLSA）测试了四种不同水平的对侧噪声对语音清晰度的影响。通过使用功能磁共振成像的视觉语音测试，预先评估了语音处理的皮质侧偏化。无论对讲的是哪只耳朵，对侧OLSA噪声为65或80 dB SPL都会显着降低单词的清晰度。在进行了左侧语音处理的参与者中，当语音呈现给左耳时，即当语音同侧呈现给主要处理语音的半球时，50 dB SPL对侧OLSA噪声导致语音清晰度明显降低。因此，如标准临床实践中所使用的对侧噪声，