Cortical processing of cochlear implant signals

人工耳蜗信号的皮质处理

• 批准号: 9029578
• 负责人: XIAOQIN WANG
• 金额: $ 52.76万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-12-01 至 2020-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9029578
• 关键词: Acoustics; Acute; Address; Animal Model; Animals; Area; Auditory Perception; Auditory area; Auditory system; Automobile Driving; Behavioral; Brain; Callithrix; Callithrix jacchus jacchus; Cerebral cortex; Chronic; Cochlea; Cochlear Implants; Code; Communication; Contralateral; Data; Development; Ear; Electric Stimulation; Environment; Exhibits; Foundations; Frequencies; Goals; Hearing; Hearing Aids; Human; Individual; Ipsilateral; Knowledge; Laboratories; Lateral; Left; Light; Modeling; Nature; Neuronal Plasticity; Neurons; Phase; Physiologic pulse; Population; Primates; Process; Production; Prosthesis; Research; Scheme; Signal Transduction; Stimulus; Techniques; Technology; Testing; Time; Training; auditory feedback; awake; base; design; experience; implantable device; improved; insight; neural prosthesis; public health relevance; rehabilitation strategy; relating to nervous system; research study; response; sound; sound frequency; speech processing; success

 DESCRIPTION (provided by applicant): The long-term goal of our research is to elucidate neural coding and plasticity mechanisms underlying cortical processing of cochlear implant (CI) signals in the context of vocal communication. We have established a new CI model (the common marmoset) to pursue these questions. The present application builds on that foundation and represents the next key steps towards our long-term objectives. Marmosets have a rich vocal repertoire, are highly communicative, and can potentially be used to study vocal production and auditory feedback mechanisms related to speech processing in CI subjects, which is an area that lacks suitable animal models. The hearing range of the marmoset is similar to that of humans and its auditory cortex shares similar organizations as humans. These similarities make it a highly valuable animal model to address issues in CI research pertaining to human users. The PI's laboratory is a pioneer in marmoset research, and the proposed research will benefit from techniques we developed over the past two decades to study marmoset auditory cortex in awake and behaving conditions. Aim 1 will compare auditory cortex neuron selectivity for acute and chronic CI stimuli. Our preliminary studies showed that primary auditory cortex (A1) neurons that are acoustically selective to both frequency and sound level are often unresponsive to electrical stimulation of the cochlea. It is not clear how these highly selective cortical neurons behave in the chronic CI stimulation condition. Aim 2 will define cortical representations of time-varying cochlear implant stimuli in alert primates. Temporally modulated signals are critical components of vocal communication sounds of humans and animals. Previous CI studies in anesthetized animals have encountered limits of cortical phase locking between 20-60 Hz, leaving unanswered the question of how higher frequency envelope modulations, which can be perceived by CI users, are represented in auditory cortex. Aim 3 will characterize neural responses to CI stimulation in non-primary auditory cortex. Currently, our knowledge on how the auditory cortex processes CI input has almost exclusively relied on studies of A1. Little is known about how cortical areas outside A1 are engaged by CI stimulation at the single neuron level. The results of these aims will help elucidate cortical processes involved in electric hearing and provide insights for improving current cochlear implant designs.

 描述（由申请人提供）：我们研究的长期目标是阐明语音交流背景下人工耳蜗（CI）信号皮质处理的神经编码和可塑性机制。我们建立了一个新的CI模型（普通绒猴）来探讨这些问题。本申请建立在这一基础上，代表了实现我们长期目标的下一个关键步骤。绒猴具有丰富的声音库，是高度沟通的，并且可以潜在地用于研究与CI受试者的语音处理相关的声音产生和听觉反馈机制，这是一个缺乏合适的动物模型的领域。绒猴的听觉范围与人类相似，其听觉皮层与人类共享类似的组织。这些相似性使其成为一个非常有价值的动物模型，以解决与人类用户有关的CI研究中的问题。PI的实验室是绒猴研究的先驱，拟议的研究将受益于我们在过去二十年中开发的技术，以研究绒猴在清醒和行为条件下的听觉皮层。目的1将比较急性和慢性CI刺激的听皮层神经元选择性。我们的初步研究表明，初级听觉皮层（A1）神经元，是声学选择性的频率和声级往往是无反应的电刺激耳蜗。尚不清楚这些高度选择性的皮层神经元在慢性CI刺激条件下如何表现。目标2将定义 警觉灵长类动物时变耳蜗植入刺激的皮质表征。时间调制信号是人类和动物语音交流的重要组成部分。先前在麻醉动物中的CI研究遇到了20-60 Hz之间的皮层相位锁定的限制，留下了未回答的问题，即CI用户可以感知的更高频率的包络调制如何在听觉皮层中表示。目的3将描述非初级听觉皮层对CI刺激的神经反应。目前，我们关于听觉皮层如何处理CI输入的知识几乎完全依赖于A1的研究。很少有人知道A1以外的皮层区域是如何参与CI刺激在单个神经元水平。这些目标的结果将有助于阐明参与电听觉的皮层过程，并为改进目前的人工耳蜗设计提供见解。