Department of Speech, Language and Hearing Sciences, University of Texas at Austin, Austin, Texas 78712
Communication Sciences Research Center, Cincinnati Children's Hospital, Cincinnati, Ohio 45229.
J Neurosci. 2023 Jun 21;43(25):4642-4649. doi: 10.1523/JNEUROSCI.2182-22.2023. Epub 2023 May 23.
Auditory experience plays a critical role in hearing development. Developmental auditory deprivation because of otitis media, a common childhood disease, produces long-standing changes in the central auditory system, even after the middle ear pathology is resolved. The effects of sound deprivation because of otitis media have been mostly studied in the ascending auditory system but remain to be examined in the descending pathway that runs from the auditory cortex to the cochlea via the brainstem. Alterations in the efferent neural system could be important because the descending olivocochlear pathway influences the neural representation of transient sounds in noise in the afferent auditory system and is thought to be involved in auditory learning. Here, we show that the inhibitory strength of the medial olivocochlear efferents is weaker in children with a documented history of otitis media relative to controls; both boys and girls were included in the study. In addition, children with otitis media history required a higher signal-to-noise ratio on a sentence-in-noise recognition task than controls to achieve the same criterion performance level. Poorer speech-in-noise recognition, a hallmark of impaired central auditory processing, was related to efferent inhibition, and could not be attributed to the middle ear or cochlear mechanics. Otitis media is the second most common reason children go to the doctor. Previously, degraded auditory experience because of otitis media has been associated with reorganized ascending neural pathways, even after middle ear pathology resolved. Here, we show that altered afferent auditory input because of otitis media during childhood is also associated with long-lasting reduced descending neural pathway function and poorer speech-in-noise recognition. These novel, efferent findings may be important for the detection and treatment of childhood otitis media.
听觉体验在听力发育中起着至关重要的作用。由于中耳炎这一常见的儿童疾病导致的发育性听觉剥夺，即使中耳病理得到解决，中枢听觉系统也会产生长期的变化。由于中耳炎导致的声音剥夺的影响在很大程度上已在上行听觉系统中进行了研究，但仍需在下行途径中进行检查，该途径从听觉皮层经脑干到耳蜗。传出神经系统的改变可能很重要，因为下行橄榄耳蜗通路会影响传入听觉系统中瞬态声音在噪声中的神经表现，并且被认为与听觉学习有关。在这里，我们发现，与对照组相比，有中耳炎病史的儿童的内侧橄榄耳蜗传出神经的抑制强度较弱；该研究包括男孩和女孩。此外，与对照组相比，有中耳炎病史的儿童在句子噪声识别任务中需要更高的信噪比才能达到相同的标准性能水平。言语感知受损是中枢听觉处理受损的标志，与传出神经抑制有关，不能归因于中耳或耳蜗力学。中耳炎是儿童第二大常见就医原因。先前，由于中耳炎导致的听觉体验恶化与上行神经通路的重组有关，即使中耳病理得到解决也是如此。在这里，我们发现，儿童时期由于中耳炎而导致的传入听觉输入改变也与持久的下行神经通路功能下降和言语感知受损有关。这些新的传出发现可能对儿童中耳炎的检测和治疗很重要。
