Faculty of Electrical Engineering, Medical Engineering and Computer Sciences, Peter Osypka Institute of Medical Engineering, University of Applied Sciences Offenburg, Offenburg, Germany.
Bio-Inspired Information Processing, Munich Institute of Biomedical Engineering, Technical University of Munich, Garching, Germany.
Trends Hear. 2023 Jan-Dec;27:23312165231171987. doi: 10.1177/23312165231171987.
Subjects utilizing a cochlear implant (CI) in one ear and a hearing aid (HA) on the contralateral ear suffer from mismatches in stimulation timing due to different processing latencies of both devices. This device delay mismatch leads to a temporal mismatch in auditory nerve stimulation. Compensating for this auditory nerve stimulation mismatch by compensating for the device delay mismatch can significantly improve sound source localization accuracy. One CI manufacturer has already implemented the possibility of mismatch compensation in its current fitting software. This study investigated if this fitting parameter can be readily used in clinical settings and determined the effects of familiarization to a compensated device delay mismatch over a period of 3-4 weeks. Sound localization accuracy and speech understanding in noise were measured in eleven bimodal CI/HA users, with and without a compensation of the device delay mismatch. The results showed that sound localization bias improved to 0°, implying that the localization bias towards the CI was eliminated when the device delay mismatch was compensated. The RMS error was improved by 18% with this improvement not reaching statistical significance. The effects were acute and did not further improve after 3 weeks of familiarization. For the speech tests, spatial release from masking did not improve with a compensated mismatch. The results show that this fitting parameter can be readily used by clinicians to improve sound localization ability in bimodal users. Further, our findings suggest that subjects with poor sound localization ability benefit the most from the device delay mismatch compensation.
受试者在一只耳朵中使用人工耳蜗 (CI)，在对侧耳朵中使用助听器 (HA)，由于两种设备的处理延迟不同，因此会遭受刺激时间不匹配的问题。这种设备延迟不匹配会导致听神经刺激的时间不匹配。通过补偿设备延迟不匹配来补偿这种听神经刺激不匹配，可以显著提高声源定位精度。一家 CI 制造商已经在其当前的拟合软件中实现了这种不匹配补偿的可能性。本研究探讨了这种拟合参数是否可以在临床环境中方便地使用，并确定了在 3-4 周的时间内对补偿后的设备延迟不匹配进行熟悉的效果。在 11 名双耳 CI/HA 用户中，测量了有无补偿设备延迟不匹配时的声源定位准确性和噪声下的言语理解能力。结果表明，当补偿设备延迟不匹配时，声源定位偏差改善到 0°，这意味着消除了 CI 的定位偏差。RMS 误差提高了 18%，但这种改善没有达到统计学意义。这些效果是急性的，在 3 周的适应期后没有进一步改善。对于言语测试，补偿后的不匹配并没有改善空间掩蔽释放。结果表明，该拟合参数可以方便地由临床医生用于提高双耳用户的声源定位能力。此外，我们的研究结果表明，声源定位能力差的受试者最受益于设备延迟不匹配补偿。
