The Occipital Cortex in Cross-Modal Sensory Processing

跨模式感觉处理中的枕叶皮层

• 批准号: 7104935
• 负责人: Lotfi Merabet
• 金额: $ 15.03万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-01 至 2010-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7104935
• 关键词: behavior test; behavioral /social science research tag; bioimaging /biomedical imaging; blindness; brain mapping; clinical research; functional magnetic resonance imaging; human subject; neural information processing; neural plasticity; occipital lobe /cortex; patient oriented research; touch; transcranial magnetic stimulation; visual perception

DESCRIPTION (provided by applicant): Current evidence suggests that the occipital cortex (normally associated with visual perception) actively participates in non-visual sensory tasks. For example, it has been demonstrated both in sighted and blind individuals that this area is implicated in the processing of sensory information obtained through touch. The purpose of this research proposal is to investigate the neurophysiology and neuroplasticity of cross-modal sensory interactions. Specifically, the study has three aims: (Aim 1). In congenitally blind and sighted individuals, what roles do occipital (visual) cortical areas play in tactile spatial discrimination tasks? (Aim 2) Does the tactile exploration of complex objects and visual scenes (e.g., faces and houses) by sighted and blind individuals activate known higher-order visual areas? (Aim 3) Does tactile stimulation modulate occipital cortex function? We will employ fMRI and TMS to pursue these questions. Subjects will perform spatial discrimination and object recognition tasks to tactile presented stimuli (simple raised dot texture patterns and complex objects such as faces), fMRI will be used to map and compare the cortical areas activated during these tactile tasks in the sighted and blind. In a second set of experiments, we will assess the modulation of occipital cortex activity and function during a cross-modal visuo-tactile task. TMS will be used to induce and assess changes in phosphene perception as a function of simultaneous tactile stimulation. The candidate wishes to learn, master and combine the techniques of fMRI and TMS with the goal of becoming an independent clinician-scientist. The proposed experiments will contribute to our understanding as to how objects are represented within the visual brain and how information obtained from touch contributes to this processing. Furthermore, comparing these processes in the blind will help uncover the adaptive mechanisms underlying object representation in the absence of vision. These results are likely to have implications for both the rehabilitation and education of the blind and visually impaired.

描述（由申请人提供）：当前的证据表明，枕皮层（通常与视觉感知相关）积极参与非视觉感觉任务。例如，在视力和盲人中都证明了该领域与通过触摸获得的感官信息的处理有关。该研究建议的目的是研究跨模式感觉相互作用的神经生理学和神经塑性。具体而言，该研究具有三个目的：（目标1）。在先天盲人和视力的人中，枕骨（视觉）皮质区域在触觉空间歧视任务中扮演什么角色？ （AIM 2）通过视力和盲人对复杂物体和视觉场景（例如面孔和房屋）的触觉探索是否会激活已知的高阶视觉区域？ （AIM 3）触觉刺激调节枕皮层功能是否功能？我们将采用fMRI和TMS来提出这些问题。受试者将对触觉刺激执行空间歧视和对象识别任务（简单升高的点纹理模式和复杂的对象（例如面孔）），fMRI将用于绘制和比较在视线和盲目的这些触觉任务中激活的皮质区域。在第二组实验中，我们将评估在跨模式视觉触诊任务中枕皮层活性和功能的调节。 TMS将用于诱导和评估磷光感知的变化，这是同时触觉刺激的函数。候选人希望学习，掌握和结合fMRI和TMS的技术，以成为独立的临床医生。提出的实验将有助于我们对视觉大脑中对象的表示以及从触摸获得的信息如何有助于此处理的理解。此外，比较盲人中的这些过程将有助于在没有视力的情况下发现对象表示的基础机制。这些结果可能对盲人和视力障碍的康复和教育具有影响。