Department of Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston, MA, USA.
Eaton-Peabody Laboratories, Boston, MA, USA.
Trends Hear. 2023 Jan-Dec;27:23312165231176157. doi: 10.1177/23312165231176157.
Dynamic focusing cochlear implant strategies aim to emulate normal cochlear excitation patterns by varying the degree of current focusing as a function of input level. Results on the speech perception benefits of these strategies have been mixed. In previous studies, channel interaction coefficients (), which mediate the relationship between current level and degree of focusing, were fixed across channels and participants. Fixing without accounting for channel interaction and the current required to accurately stimulate target neurons may elicit suboptimal loudness growth and speech perception. This study tested whether individualizing improved speech perception relative to fixed- and monopolar strategies. Fourteen ears of implanted adults were programmed with 14-channel strategies matched on pulse duration, pulse rate, filtering, and loudness. Sentence recognition and vowel identification was measured at 60 dB SPL equivalent in quiet and four-talker babble. On the group level, speech recognition in quiet and noise was similar between strategies. On the individual level, there were participants who benefitted with dynamic focusing strategies for speech perception in noise. Patterns of benefit were generally unclear, beyond associations between focused thresholds, duration of hearing loss, and individual- benefit. Participants rated dynamic focusing like monopolar in clarity and ease of listening. Almost all participants expressed their willingness to use the strategies in a take-home trial. These results suggest that while individualizing does not benefit all, there are individuals who benefit, for which the electrode-neuron interface may play a role. Future studies will evaluate acclimatization of dynamic focusing strategies using take-home trials.
动态聚焦人工耳蜗植入策略旨在通过根据输入水平改变电流聚焦程度来模拟正常耳蜗的兴奋模式。这些策略在言语感知方面的益处的研究结果喜忧参半。在之前的研究中，作为电流水平与聚焦程度之间关系的中介的通道交互系数 () 在通道和参与者之间是固定的。如果不考虑通道交互和准确刺激目标神经元所需的电流来固定 ，可能会导致响度增长和言语感知不理想。本研究测试了个性化 相对于固定和单极策略是否能提高言语感知。14 名植入成人的耳朵用 14 通道策略进行编程，这些策略在脉冲持续时间、脉冲率、滤波和响度方面匹配。在安静和四人背景噪声下以 60dB SPL 等效测量句子识别和元音识别。在群体水平上，在安静和噪声中的言语识别策略之间没有差异。在个体水平上，有些参与者在噪声中的言语感知中受益于动态聚焦策略。受益模式通常不清楚，除了与聚焦阈值、听力损失持续时间和个体受益有关之外。参与者对动态聚焦的清晰度和可听度评价与单极相似。几乎所有参与者都表示愿意在家庭试用中使用这些策略。这些结果表明，虽然个性化 并不对所有人都有益，但有些人受益，这可能与电极-神经元界面有关。未来的研究将使用家庭试用评估动态聚焦策略的适应情况。
