Mapping the Deaf Auditory Cortex

绘制聋人听觉皮层图

• 批准号: 7045951
• 负责人: JOHN W BELLIVEAU
• 金额: $ 8.54万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-04-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7045951
• 关键词: auditory cortex; brain electrical activity; brain mapping; clinical research; deafness; electroencephalography; functional magnetic resonance imaging; human subject; magnetoencephalography; neural plasticity; neuronal transport; thalamic nuclei; thalamocortical tract

DESCRIPTION (provided by applicant): Traditionally, the sensory areas of the brain were believed to be exclusively devoted for processing of sensory information from one set of sensory organs, i.e., uni-modal. Increasing evidence from both animal and human studies now suggest that even the very primary sensory cortices have the capacity to process information from the other modalities. Greater understanding of the neural mechanisms underlying cross-modal plasticity is crucial for the rehabilitation of sensory deprived humans and development of neural prostheses. Recent imaging studies on congenitally deaf adults have shown that the deaf "auditory" cortex can process both visual and tactile information. However, the functional organization of the deaf "auditory" cortex is not known, as spatiotemporal processing of both visual and tactile information has not been investigated in the same subjects. Furthermore, the mere fact that the auditory cortices of the congenitally deaf can be activated by stimuli of different sensory modalities tells us very little about the level of the auditory pathway where these plastic changes take place. The measured cortical activations could reflect reorganization of the thalamic nuclei, and/or plasticity in thalamo-cortical as well as in cortico-cortical connections. In Specific Aim 1 the investigators will delineate structural plasticity both at the cortical and sub-cortical level. They will use anatomical and diffusion tensor magnetic resonance imaging in a cohort of congenitally deaf and age-matched hearing subjects to reveal putative thalamic and axonal connectivity differences. In Specific Aim 2 the investigators will combine functional magnetic resonance imaging with electromagnetic recordings to reveal the possible spatiotemporal differences in the activation of the deaf "auditory" cortex during visual and vibratory tactile stimulation. This will allow the investigators to distinguish whether overlapping or separate neuronal networks support the cross-modal plasticity of the deaf 'auditory' cortex.

描述（由申请人提供）：传统上，大脑的感觉区域被认为专门用于处理来自一组感觉器官（即单模态）的感觉信息。 现在，来自动物和人类研究的越来越多的证据表明，即使是最初级的感觉皮层也有能力处理来自其他模式的信息。 更好地理解跨模式可塑性背后的神经机制对于感觉缺失人类的康复和神经假体的开发至关重要。 最近对先天性耳聋成年人的成像研究表明，耳聋的“听觉”皮层可以处理视觉和触觉信息。 然而，聋人“听觉”皮层的功能组织尚不清楚，因为尚未在同一受试者中研究视觉和触觉信息的时空处理。 此外，先天性聋人的听觉皮层可以被不同感觉方式的刺激激活，这一事实并不能告诉我们有关发生这些可塑性变化的听觉通路的水平的信息。 测量的皮质激活可以反映丘脑核团的重组和/或丘脑-皮质以及皮质-皮质连接的可塑性。 在具体目标 1 中，研究人员将描述皮质和皮质下水平的结构可塑性。 他们将在一组先天性耳聋和年龄匹配的听力受试者中使用解剖和扩散张量磁共振成像，以揭示假定的丘脑和轴突连接差异。 在具体目标 2 中，研究人员将功能性磁共振成像与电磁记录相结合，揭示视觉和振动触觉刺激过程中聋人“听觉”皮层激活可能存在的时空差异。 这将使研究人员能够区分重叠或独立的神经元网络是否支持聋人“听觉”皮层的跨模式可塑性。