Electrocorticographic Study of Categorical Phoneme Perception in the Human Tempor

人类时间范畴音素感知的皮层电图研究

• 批准号: 7406951
• 负责人: Edward Chang
• 金额: $ 5.13万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7406951
• 关键词: Acoustics; Auditory area; Auditory system; Autistic Disorder; Behavioral; Brain; Categories; Chronic; Cognition; Collaborations; Communication; Communication impairment; Complex; Comprehension; Discrimination; Dyslexia; Electrocorticogram; Electrodes; Epilepsy; Evoked Potentials; Functional Magnetic Resonance Imaging; Human; Impairment; Implant; Invasive; Investigation; Joints; Language; Language Development; Lateral; Light; Linguistics; Liquid substance; Localized; Magnetoencephalography; Modality; Neurosurgeon; Neurosurgical Procedures; Patients; Pattern; Perception; Phonetics; Process; Property; Psychophysiology; Publishing; Research; San Francisco; Scalp structure; Signal Transduction; Speech; Speech Perception; Speech Sound; Stimulus; Superior temporal gyrus; Surface; Techniques; Temporal Lobe; Training; Training Programs; Voice; base; density; direct application; improved; neuroimaging; relating to nervous system; remediation; response; sound; spatiotemporal; speech processing; tool

DESCRIPTION (provided by applicant): The basic mechanisms underlying speech perception are unclear. The human auditory system regularly processes highly acoustically variable inputs into invariant representations of speech- a critical function for human communication. In order to better understand this property, I propose to investigate the cortical representations of speech sounds during categorical perception (CP). CP occurs when a change in a variable such a phonemic contrast along a physical continuum is perceived, not as gradual but as an instance of discrete category. Previous functional neuroimaging research has implicated the superior temporal gyrus and sulcus of the lateral temporal cortex in phonemic processing, but not the precise means by which the cortex represents those sounds. During a one-year training program, I plan to use electrocorticography (ECoG), the direct application of electrodes to the brain surface for recording cortical activity, to examine categorical speech processing in the superior temporal gyrus. I will utilize a high-density ECoG array and signal analysis techniques during passive listening to speech stimuli in six epilepsy patients with chronic implanted subdural grids. Phonetic discrimination and identification behavioral tasks will be performed pre-operatively, and in additional healthy normal subjects, to determine boundaries for CP transitions. Phoneme stimuli will focus on three contrasts with well-known categorical psychophysical properties: /b/ vs /d/, /r/ vs /I/, and /d/ vs /t/. We hypothesize that a highly specific spatiotemporal pattern of evoked potential and/or neural oscillatory activity will reveal an emergent categorical representation of speech phonemic contrasts which closely reflects behavioral thresholds, as opposed to a continuously linear representation of acoustic parameters. An improved understanding of speech processing mechanisms has direct implications for the origin and remediation of communication disorders, including autism, dyslexia, and language learning impairment.

描述（由申请人提供）：言语感知的基本机制尚不清楚。人类听觉系统有规律地将高度声学可变的输入处理成语音的不变表示-这是人类交流的关键功能。为了更好地理解这一属性，我建议调查的皮质表征的语音在分类知觉（CP）。当一个变量的变化，如音位对比沿着物理连续统被感知时，CP发生，不是逐渐的，而是作为离散范畴的一个实例。先前的功能性神经影像学研究表明，上级颞回和外侧颞叶皮层的沟参与了语音处理，但并没有发现皮层表征这些声音的精确方式。在为期一年的培训计划中，我计划使用皮层电图（ECoG），即直接将电极应用于大脑表面以记录皮层活动，以检查上级颞回的分类语音处理。我将利用高密度皮层脑电图阵列和信号分析技术，在被动听语音刺激在六个癫痫患者慢性植入硬膜下网格。将在术前和其他健康正常受试者中进行语音辨别和识别行为任务，以确定CP转换的边界。音素刺激将集中在与众所周知的分类心理物理特性的三个对比上：/B/ vs /d/，/r/ vs /I/，和/d/ vs /t/。我们假设，一个高度具体的时空模式的诱发电位和/或神经振荡活动将揭示一个紧急的分类表示的语音音位对比，密切反映行为阈值，而不是一个连续的线性表示的声学参数。对言语加工机制的更好理解对沟通障碍的起源和补救有直接的影响，包括自闭症，阅读障碍和语言学习障碍。