Collaborative Research: Multisensory Influences On Touch Perception--fMRI, MEG, and TMS Studies

在我们的日常生活中，我们经常面对来自多种感官模式的信息。最近，人们对以一种感觉模态呈现的刺激影响另一种感觉模态的情况越来越感兴趣。例如，蚊子的嗡嗡声似乎增强了我们皮肤对触觉（触觉刺激）的敏感性；看到昆虫在别人的手臂上爬行似乎会影响我们自己的触觉。尽管最近有几项研究考察了听觉和视觉对触觉的影响，但负责这些相互作用的大脑机制却知之甚少。由美国国家科学基金会资助的托尼·罗（莱斯大学）和迈克尔·比彻姆（休斯顿德克萨斯大学健康科学中心）将联合使用聚合方法来研究孤立的触觉处理以及人类大脑中视觉和听觉对触觉的影响。我们将进行心理物理研究，以确定视觉和听觉对触觉感知影响的最佳刺激参数。功能磁共振成像（fMRI）、经颅磁刺激（TMS）和脑磁图（MEG）将用于定位涉及整合多感觉信息的大脑区域。虽然大多数实验将使用正常对照进行，但额外的一系列实验将在一位中风后获得听觉-触觉联觉的独特患者中进行。病人左手和手臂的触觉受损，但他现在在那个区域对声音有触觉反应。将对该患者进行心理物理和影像学实验，以确定导致联觉的神经机制，特别是可塑性的神经变化是否重构了患者的体感皮层，使其现在对声音作出反应。这些研究不仅将加深我们对多感觉整合的理解，而且将对人类大脑的一般信息处理机制提供更深入的认识。这些知识将有助于开发更好的康复工具，为先天性或后天的感觉缺陷的一个或多个感觉系统的患者。此外，这项研究将更好地了解发生在成人大脑中的自然和脑损伤引起的变化的机制。这笔资金将用于支持休斯敦地区认知神经科学和脑成像领域的本科生、研究生和博士后学员的研究培训机会。除了培养下一代脑科学家外，这项研究的结果将通过科学和非专业出版物以及其他媒体渠道传播，从而使社会对人类大脑有更深入的了解和欣赏。

In our everyday lives, we are frequently confronted with information from multiple sensory modalities. Recently, there has been increasing interest in the circumstances under which stimuli presented in one sensory modality influence sensations in a different modality. For instance, the sound of a mosquito buzzing seemingly enhances sensitivity to touch (tactile stimulation) on our skin; seeing an insect crawling on someone else's arm seems to affect our own tactile perception. Despite several recent studies examining the influence of audition and vision on touch, the brain mechanisms responsible for these interactions are poorly understood. An NSF-funded collaborative effort of Tony Ro (Rice University) and Michael Beauchamp (University of Texas Health Science Center, Houston) will use a combination of converging methods to examine tactile processing in isolation and the influence of vision and audition on touch in the human brain. Psychophysical studies will be conducted to determine the optimal stimulus parameters that demonstrate an influence of vision and audition on tactile perception. Functional magnetic resonance imaging (fMRI), transcranial magnetic stimulation (TMS), and magnetoencephalography (MEG) will be used to localize the brain regions involved with integrating multisensory information. While most of these experiments will be conducted using normal controls, an additional series of experiments will be conducted in a unique patient who acquired auditory-tactile synesthesia following a stroke. Tactile sensitivity on the patient's left hand and arm was impaired, but he now feels tactile sensations in that area in response to sounds. Psychophysical and imaging experiment will be completed on this patient to determine the neural mechanisms responsible for the synesthesia, especially whether plastic neural changes have reconstituted the patient's somatosensory cortex so that it is now responds to sounds.These studies will not only better our understanding of multisensory integration, but will provide a deeper appreciation of general information processing mechanisms of the human brain. Such knowledge will contribute towards the development of better rehabilitative tools for patients with congenital or acquired sensory deficits to one or more of the sensory systems. Additionally, this research will provide a better understanding of the mechanisms of natural and brain-damaged induced changes that take place in the adult human brain. The funding will be used to support research training opportunities for undergraduate, graduate, and post-doctoral trainees in cognitive neuroscience and brain imaging in the Houston area. In addition to training the next generation of brain scientists, the findings of this research will be disseminated through scientific and lay publications, as well as other media outlets, allowing for a deeper understanding and appreciation of the human brain in society.