Cortical substrates for processing auditory feedback during vocalization

描述(申请人提供)：人类交流依靠听觉来理解他人的言语，并监测、学习和保持自己的言语。在嘈杂的声学环境中，通过听觉反馈听到自己的语音是保持正常语音的关键。了解听觉皮质中的听觉-运动相互作用对于理解听觉在发声、感知和产生中的作用是至关重要的。在人类和非人类灵长类动物普遍存在的现象中，在发声之前和发声期间，听觉皮质的神经活动受到抑制。这种发声诱导的抑制可能反映了一种必然的放电信号，该信号参与了在嘈杂环境中对自己声音的皮质表征或纠正发声错误。虽然有证据表明，嘴侧和后侧区域功能专门化，用于处理交流声音，但听觉皮质区域专门用于处理自身产生的发声，尚未被描述。间接证据表明，从运动前皮质投射的神经元激活了听觉皮质中的抑制性中间神经元，但目前还没有明确的证据表明，这一途径或其他途径是否将发声诱导的抑制传递到听觉皮质。目的1验证发声过程中听觉皮质带状和旁区神经元优先受到抑制的假说。目的2验证发声诱导的听觉皮层抑制是由发声相关的运动前皮质神经信号引起的假说。本研究的目的是进一步了解非人类灵长类动物大脑在主动听觉过程中处理听觉反馈的神经基础。拟议研究的结果将阐明听觉皮质中感觉运动整合的神经回路，并有助于更好地了解听力损失和人工耳蜗植入患者的沟通障碍的原因，如言语障碍、口吃和学习语音。

DESCRIPTION (provided by applicant): Human communication relies on hearing sensation to interpret other's speech and to monitor, learn, and maintain one's own speech. Hearing one's own speech through auditory feedback is crucial to maintain normal speech in noisy acoustic environment. Understanding auditory-motor interactions in auditory cortex is essential to understanding the role of hearing in vocalization perception and production. In a phenomenon common to human and non-human primates, neural activity in auditory cortex is suppressed before and during vocalization. This vocalization-induced suppression may reflect a corollary discharge signal involved in cortical representation of one's own voice in a noisy environment or correcting vocal errors. While there is evidence for functional specialization of rostral and laterl regions for processing communication sounds, auditory cortex regions specialized for processing self-produced vocalizations have not been described. Indirect evidence suggests that neurons projecting from premotor cortex activate inhibitory interneurons in auditory cortex, but there is not clear evidence whether this or another pathway delivers vocalization-induced suppression to auditory cortex. Aim 1 will test the hypothesis that neurons in belt and parabelt regions of auditory cortex are preferentially suppressed during vocalization. Aim 2 will test the hypothesis that vocalization-induced suppression in auditory cortex is caused by neural signals from vocalization-related premotor cortex The goal of the proposed research is to further our understanding of the neural substrates for processing auditory feedback during active hearing in the non-human primate brain. Findings from the proposed studies will elucidate the neural circuitry for sensorimotor integration in auditory cortex and help better understand causes of communication disorders such as speech disorders, stuttering, and learning speech in hearing loss and cochlear implant patients.