Development of electrophysiological auditory response for speech

描述(由申请人提供)：了解正常听力(NH)个体对言语的听觉反应的电生理发展是识别言语感知缺陷儿童异常言语处理延迟的必要步骤。我将使用脑电(EEG)从电生理学的角度来描述语言听觉反应的发展。我将确定特定于年龄的神经振荡模板，这些模板区分语音的时间(Aim1)和频谱(AIM2)属性的处理，特别是起始上升时间(ORT)和共振峰结构。电生理变化将基于代表大脑振荡活动动力学的三个维度来评估：(1)神经响应与声学特性的时间对准的强度，称为锁相指数(PLI)，(2)神经响应(SP)的频谱功率，以及(3)PLI或SP响应相对于语音开始的潜伏期。这些测量反映了可能特定于某些语音特性的不同神经机制。根据行为测量，儿童在处理语音时，对共振峰轨迹的权重比对包络结构的权重更大。随着年龄的增长，他们学会利用语音信号提供的包络信息(例如ORT)。与行为研究结果相比，脑电结果显示，儿童低频振荡活动的PLI与编码声音的频谱方面有关，而成年人利用低频和高频PLI来处理声音的频谱信息。此外，PLI延迟与处理ORT相关。低频和中频振荡活动的PLI潜伏期在7-9岁左右开始随着ORT的变化而移动。总之，行为学和电生理学的研究结果表明，低频和高频PLI可能在共振峰加工的发展中发挥作用，而低频和中频振荡活动的PLI潜伏期在ORT加工的发展中可能发挥作用。基于这项研究的年龄模板随后将被用于识别听觉反应的发展，以用于言语感知缺陷儿童的言语的时间和频谱处理。 公共卫生相关性：拟议的研究将有助于扩大我们目前对听力正常儿童听觉皮质发育的了解。我们将确定与特定言语属性的发展相关的特定大脑活动。在未来，我们将利用从这项研究中获得的知识来评估言语和语言缺陷儿童的听觉发育。

DESCRIPTION (provided by applicant): Understanding the electrophysiological development of the auditory response to speech in normal hearing (NH) individuals is a necessary step in identifying abnormal speech processing delays in children with speech perception deficits. I will characterize the development of the auditory response to speech electrophysiologically using electroencephalography (EEG). I will identify age-specific templates of the neural oscillations that distinguish the processing of temporal (Aim1) and spectral (Aim2) properties of speech, specifically the onset rise time (ORT) and formant structure, respectively. Electrophysiological changes will be assessed based on three dimensions representing the dynamics of brain oscillatory activity: (1) the strength of temporal alignment of the neural response to the acoustical property, referred to as phase-locking index (PLI), (2) the spectral power of the neural response (SP), and (3) the latency of PLI or SP responses with respect to the onset of speech. These measures reflect different neural mechanisms that may be specific to certain speech properties. Based on behavioral measures, children weight formant trajectories more so than envelope structure when processing speech sounds. As they age, they learn to utilize envelope information (e.g. ORT) provided by the speech signal. In comparison to behavioral findings, EEG results revealed that PLI of low- frequency oscillatory activity is associated with coding spectral aspects of sounds in children, while adults utilize low- and high-frequency PLI for processing spectral information of sound. Also, PLI latency is associated with processing the ORT. PLI latency of the low- and mid-frequency oscillatory activity starts to shift with ORT around age 7-9. Together, behavioral and electrophysiological findings point to a possible role of low- and high-frequency PLI in development of formant processing, and a role for PLI latency of low- and mid-frequency oscillatory activity in development of ORT processing. Age- templates based on this study will subsequently be used to identify auditory response development for the temporal and spectral processing of speech in children with speech perception deficits. PUBLIC HEALTH RELEVANCE: The proposed research will help expand our current knowledge of auditory cortex development in normal hearing children. We will identify specific brain activity associated with the development of specific speech properties. In the future, we will use the knowledge obtained from this research to assess auditory development in children with speech and language deficits.