Crossmodal interactions in selective attention: A combined human lesion/transcranial magnetic stimulation study

注意力的各个方面在指导人类行为方面至关重要。大脑使用这些机制来增强对当前与行为相关的感觉信息的处理，并抑制不相关的感觉信息。虽然动物和人类的研究都有相当多的知识，关于注意如何在个体感觉通道(视觉、触觉、听觉等)中运作，但对注意力如何整合这些不同通道的信息知之甚少。理解这些“跨模式”注意机制很重要，原因有几个。首先，主要感觉区域的大部分大脑活动是由个体的注意状态调节的，因此发现跨通道注意是如何工作的将有助于我们从总体上理解感觉加工的神经机制。其次，人类感知的最基本方面从根本上依赖于注意力；如果没有注意力，我们就会认为来自不同感官的输入是零碎的，而不是捆绑在一起形成连贯的多模式表征。最后，许多后天和发育性神经障碍的特征是注意力受损。这个项目将研究中风患者的跨模式空间注意，这些患者的单一视觉脑区(枕叶皮质)或多感官脑区(顶叶皮质)受损。它还将测量健康参与者的跨模式相互作用的程度，使用皮质经颅磁刺激(TMS)来诱导可逆的、模仿中风患者的“虚拟”损伤。这项研究的具体目标是解释视觉和触觉的输入如何相互作用以产生连贯的感知；并通过利用任何保留的跨模式注意机制，为开发更有效的中风患者康复技术提供经验基础。

Aspects of attention are of central importance in guiding human behaviour. The brain uses these mechanisms to enhance the processing of sensory information that is currently relevant for behaviour, and to suppress irrelevant sensory information. Although there is a considerable body of knowledge, from both animal and human research, on how attention operates within individual sensory modalities (vision, touch, hearing, etc.), very little is known about how attention integrates information across these different modalities. An understanding of these 'crossmodal' attentional mechanisms is important for several reasons. First, much brain activity in primary sensory areas is modulated by the attentive state of the individual, so discovering how crossmodal attention works will facilitate our understanding of the neural mechanisms of sensory processing generally. Second, the most basic aspects of human perception are fundamentally dependent upon attention; without attention we would perceive inputs from the different senses as fragmentary, rather than as bound together into coherent multimodal representations. Finally, many acquired and developmental neurological disorders are characterised by debilitating impairments of attention. This project will examine crossmodal spatial attention in stroke patients with damage to an exclusively visual brain area (occipital cortex), or to a multisensory brain area (parietal cortex). It will also measure the extent of crossmodal interactions in healthy participants, using cortical transcranial magnetic stimulation (TMS) to induce reversible, 'virtual' lesions that mimic those of the stroke patients. The specific goals of the research are to explain how inputs from the senses of vision and touch interact to give rise to coherent perception; and to provide an empirical foundation for the development of more effective rehabilitative techniques for stroke patients, by exploiting any preserved crossmodal attentional mechanisms.