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个感官通道的信息。最近，人们对在一种感觉通道中呈现的刺激影响另一种通道中的感觉的情况越来越感兴趣。例如，蚊子嗡嗡的声音似乎会增强我们皮肤对触摸(触觉刺激)的敏感度；看到昆虫爬在别人的手臂上似乎会影响我们自己的触觉感知。尽管最近有几项研究考察了听觉和视觉对触觉的影响，但负责这些互动的大脑机制却知之甚少。美国国家科学基金会资助的一项由Tony Ro(莱斯大学)和Michael Beuchamp(德克萨斯大学休斯顿健康科学中心)合作的工作将使用融合方法的组合来研究孤立的触觉处理以及视觉和听力对人脑触摸的影响。将进行心理物理研究，以确定最佳刺激参数，以证明视觉和听力对触觉的影响。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。虽然大多数实验将在正常对照组中进行，但另外一系列实验将在一名中风后获得听觉-触觉联觉的独特患者身上进行。患者左手和手臂的触觉敏感度受损，但他现在感觉到该区域对声音的触觉反应。将在这名患者身上完成心理物理和成像实验，以确定导致联觉的神经机制，特别是可塑性神经变化是否重组了患者的躯体感觉皮质，使其现在对声音有反应。这些研究不仅将加深我们对多感觉整合的理解，而且将使我们更深入地了解人脑的一般信息处理机制。这些知识将有助于为先天或后天感觉障碍患者开发更好的康复工具。此外，这项研究将更好地理解成人大脑中发生的自然和脑损伤诱导变化的机制。这笔资金将用于支持休斯顿地区认知神经科学和脑成像本科生、研究生和博士后受训人员的研究培训机会。除了培训下一代脑科学家外，这项研究的结果还将通过科学和非专业出版物以及其他媒体传播，使社会能够更深入地了解和欣赏人脑。

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.