Neural determinents of sound encoding in the aging ear and brain

 描述（由申请人提供）：与年龄相关的语音识别能力下降在老年人中很常见，并对生活质量造成严重后果，包括各种健康状况较差和经济生产力下降。目前的语音康复方法主要依靠放大来恢复语音信息，提高语音识别能力。然而，整个中枢和外周听觉系统的年龄相关变化可能会限制干预策略的有效性，并导致老年人的语音识别困难。尽管了解年龄对中枢听觉系统和语音识别困难的影响越来越重要，但将这些相关现象与人类联系起来的研究却很少。拟议的项目使用互补的神经成像和行为方法来确定随着年龄的增长影响语音识别的神经衰退的结构和代谢基础。目标1中的实验研究了听觉神经中与年龄相关的缺陷如何导致不同步，并导致整个中枢听觉系统的神经功能，结构和代谢的变化，以及语音识别的下降。目标2中的实验描述了高龄如何改变皮层微结构并导致神经处理速度减慢，预计这将限制语音包络编码并导致语音识别能力下降。通过识别导致与年龄相关的语音识别下降的特定神经缺陷，拟议的项目可能会导致改进和更个性化的诊断和检测特定的与年龄相关的听觉处理缺陷，并指导开发用于放大设备和基于神经的干预措施的更个性化的信号处理算法。

 DESCRIPTION (provided by applicant): Age related declines in speech recognition are common for older adults and pose serious consequences for quality of life, which include a variety of poorer health outcomes and decreased economic productivity. Current rehabilitation methods largely depend on amplification to restore speech information and improve speech recognition. However, age-related changes throughout the central and peripheral auditory system may limit the efficacy of intervention strategies and contribute to speech recognition difficulties in older adults. Despite the growing importance of understanding the effects of age on the central auditory system and speech recognition difficulties, studies linking these related phenomena in humans are scarce. The proposed projects use complementary neuroimaging and behavioral methods to identify the structural and metabolic bases for neural declines that impact speech recognition with age. The experiments in Aim 1 examine how age-related deficits in the auditory nerve contribute to dyssynchrony and lead to changes in neural function, structure, and metabolism throughout the central auditory system, and declines in speech recognition. The experiments in Aim 2 characterize how advanced age alters cortical microstructure and contributes to slowed neural processing speed, which is predicted to limit speech envelope encoding and result in poorer speech recognition. By identifying specific neural deficits that contribute to age-related speech recognition declines, the proposed project may lead to improved and more individualized diagnoses and detection of specific age-related auditory processing deficits, and guide the development of more personalized signal processing algorithms for amplification devices and neural based interventions.