Decoding temporal features of speech in the auditory system using fMRI

描述(申请人提供)：语音信号中的时间特征对于大多数语言的正常语音感知是必不可少的。然而，在人类听觉系统中解码语音时间元素的神经解剖学基础仍然是难以捉摸的。这项拟议工作的主要目标是测试一个有影响力的假说，该假说描述了中央听觉系统如何解码语音中两个感知相关的时间调制范围：150-300毫秒和20-50毫秒范围的时间调制。为此，我们将使用新的和强大的方法来探测中枢听觉功能的功能磁共振成像(MRI)。在一项实验中，功能磁共振成像将测量大脑对语音刺激的反应，这些刺激在这两个时间调制范围内变化，以识别与语音中特定时间特征相关的神经解剖学“指纹”。第二个fMRI实验将测量大脑对语音的反应，这些语音根据快速变化的频谱特征而变化，以确定识别停辅音音素的神经解剖结构。研究结果将提供有关人类听觉系统结构和功能的重要知识，并将进一步阐明言语和语言的生物学基础。这些数据将为研究患有与言语和语言功能相关的听觉暂时性缺陷的人群提供必要的基础，包括阅读障碍和老年人。 与公共健康相关：正确地听到语音中事件的“计时”对于语音理解至关重要，这里我们试图了解大脑如何能够有效地分类语音中的计时信息。这是一个重要的问题，因为听力和语言障碍的临床人群中已经发现了听觉计时缺陷，包括老年人和阅读障碍的人。了解健康的大脑是如何整理听觉计时信息的，将有助于我们了解这些临床人群中的大脑缺陷。

DESCRIPTION (provided by applicant): Temporal features in the speech signal are essential for normal speech perception in most languages. Nevertheless, the neuroanatomical basis for decoding temporal elements of speech in the human auditory system remains elusive. The primary goal of the proposed work is to test an influential hypothesis that describes how the central auditory system decodes two perceptually-relevant ranges of temporal modulations in speech: temporal modulations in the range of 150-300 msec and 20-50 msec. To this end, we will employ novel and powerful methods for probing central auditory function using functional magnetic resonance imaging (MRI). In one experiment, functional MRI will measure brain responses to speech stimuli that vary in these two temporal modulation ranges to identify neuroanatomical "fingerprints" associated with specific temporal features in speech. A second fMRI experiment will measure brain responses to speech sounds that vary according to rapidly changing spectral features to identify neuroanatomical structures underlying the discrimination of stop-consonant phonemes. Results will provide important knowledge regarding the structure and function of the human auditory system, and will further elucidate the biological bases of speech and language. These data will provide an essential foundation for studying populations who suffer from auditory temporal deficits associated with speech and language function, including reading-impaired and elderly individuals. PUBLIC HEALTH RELEVANCE: Properly hearing the "timing" of events in speech is critical for speech understanding, and here we seek to understand how the brain is able to efficiently sort-out timing information in speech. This is an important question since auditory timing deficits have been seen in clinical populations with hearing and language impairments, including elderly and reading-impaired individuals. Understanding how the healthy brain sorts-out auditory timing information will help us understand brain deficits in these clinical populations.