{"title":"Hypoactivation of the central auditory system in listeners who are hypertolerant of background noise.","authors":"Erika Skoe, Sarah Powell","doi":"10.1152/jn.00297.2023","DOIUrl":null,"url":null,"abstract":"<p><p>Listeners exhibit varying levels of tolerance for background noise during speech communication. It has been proposed that low tolerance of background noise may be the consequence of abnormally amplified gain in the central auditory system (CAS). Here, using a dataset of young adults with normal hearing thresholds, we asked whether central gain mechanisms might also explain cases of hypertolerance of background noise, as well as cases of reduced, but not abnormal, tolerance. We used the auditory brainstem response to derive a measure of CAS gain (wave V/wave I ratio) to compare listeners' background noise tolerance while listening to speech, grouping them into three categories: hyper, high, and medium tolerance. We found that hypertolerant listeners had reduced CAS gain compared to those with high tolerance. This effect was driven by wave V not wave I. In addition, the medium tolerant listeners trended toward having reduced wave I and reduced wave V amplitudes and generally higher levels of exposure to loud sound, suggestive of the early stages of noise-compromised peripheral function without an apparent compensatory increase in central gain. Our results provide physiological evidence that <i>1</i>) reduced CAS gain may account for hypertolerance of background noise but that <i>2</i>) increased CAS gain is not a prerequisite for medium tolerance of background noise.<b>NEW & NOTEWORTHY</b> Our findings strengthen the proposed mechanistic connection between background noise tolerance and auditory physiology by suggesting a link between hypertolerance and reduced central auditory gain, measured by the auditory brainstem response.</p>","PeriodicalId":16563,"journal":{"name":"Journal of neurophysiology","volume":null,"pages":null},"PeriodicalIF":2.1000,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11427039/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of neurophysiology","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1152/jn.00297.2023","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2024/7/31 0:00:00","PubModel":"Epub","JCR":"Q3","JCRName":"NEUROSCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Listeners exhibit varying levels of tolerance for background noise during speech communication. It has been proposed that low tolerance of background noise may be the consequence of abnormally amplified gain in the central auditory system (CAS). Here, using a dataset of young adults with normal hearing thresholds, we asked whether central gain mechanisms might also explain cases of hypertolerance of background noise, as well as cases of reduced, but not abnormal, tolerance. We used the auditory brainstem response to derive a measure of CAS gain (wave V/wave I ratio) to compare listeners' background noise tolerance while listening to speech, grouping them into three categories: hyper, high, and medium tolerance. We found that hypertolerant listeners had reduced CAS gain compared to those with high tolerance. This effect was driven by wave V not wave I. In addition, the medium tolerant listeners trended toward having reduced wave I and reduced wave V amplitudes and generally higher levels of exposure to loud sound, suggestive of the early stages of noise-compromised peripheral function without an apparent compensatory increase in central gain. Our results provide physiological evidence that 1) reduced CAS gain may account for hypertolerance of background noise but that 2) increased CAS gain is not a prerequisite for medium tolerance of background noise.NEW & NOTEWORTHY Our findings strengthen the proposed mechanistic connection between background noise tolerance and auditory physiology by suggesting a link between hypertolerance and reduced central auditory gain, measured by the auditory brainstem response.
在语音交流过程中,听者对背景噪声表现出不同程度的耐受性。有人认为,对背景噪声的低容忍度可能是中枢听觉系统(CAS)增益异常放大的结果。在此,我们利用听力阈值正常的年轻成年人的数据集,询问中枢增益机制是否也能解释对背景噪声的过度容忍,以及容忍度降低但不异常的情况。我们利用听觉脑干反应得出的 CAS 增益测量值(V 波/I 波比率)来比较听者在听语音时对背景噪声的耐受性,并将他们分为三类:高耐受性、高耐受性和中等耐受性。我们发现,高耐受性听者的 CAS 增益低于高耐受性听者。此外,中等耐受性听者的趋势是波 I 和波 V 波幅减小,暴露于大音量的程度普遍较高,这表明在噪声损害外周功能的早期阶段,中枢增益没有明显的补偿性增加。我们的研究结果提供了以下生理证据:(1) CAS 增益降低可能是对背景噪声耐受性过高的原因,但 (2) CAS 增益增加并不是对背景噪声耐受性中等的先决条件。
期刊介绍:
The Journal of Neurophysiology publishes original articles on the function of the nervous system. All levels of function are included, from the membrane and cell to systems and behavior. Experimental approaches include molecular neurobiology, cell culture and slice preparations, membrane physiology, developmental neurobiology, functional neuroanatomy, neurochemistry, neuropharmacology, systems electrophysiology, imaging and mapping techniques, and behavioral analysis. Experimental preparations may be invertebrate or vertebrate species, including humans. Theoretical studies are acceptable if they are tied closely to the interpretation of experimental data and elucidate principles of broad interest.