Reverse engineering brain networks for scene and object processing with non-invasive neuromodulation

目的：来自行为测量、神经成像和临床数据的越来越多的证据表明，物体和场景是独立处理的，与直觉相反的是，场景可以被分类，而不需要识别它的任何组成物体。这项研究的目标是考察物体和场景加工之间的关系，特别是物体选择性皮质区域对场景加工的贡献及其推论。我的实验室已经证明，经颅磁刺激(TMS)对对象选择性皮质的非侵入性神经调节在整个大脑的场景处理区域和行为上都有远程影响，它改变了我们感知场景的能力。这一观察首次表明，物体和场景的处理可能并不像之前认为的那样独立，而是可能涉及相互联系。在所提出的研究方案中，我将在行为和神经水平上评估物体偏好皮层对场景知觉和场景偏好皮层对物体知觉的功能连接性。*科学方法：我将使用几种互补的方法，包括功能磁共振成像(FMRI)、功能引导的TMS和行为测量。我提出了三个主要的实验来解决以下问题：*1.在对象优先和场景优先的大脑皮层中进行了什么水平的语义编码？它是什么时候发生的？我将对对象优先和场景优先的皮质进行离线TMS，以确定这些区域对对象和场景的语义编码水平的贡献。随后，将进行在线TMS以确定神经调制的目标对象和场景区域中的时间编码。*2.物体和场景处理大脑皮层之间的功能连接是什么？我将使用连续的TMS-fMRI设计来测量对象和场景优先皮质网络中场景和对象诱导的BOLD信号，然后离线重复TMS到对象和场景优先皮质。在类似的范例中，我将在fMRI扫描过程中使用与MR兼容的线圈在线应用TMS，以观察刺激部位偏远区域的实时神经调制效应。*3.枕外侧(LO)对象选择区域和场景选择皮质之间的解剖学联系是什么？我将使用弥散张量成像(DTI)来确定这些区域之间的白质连接。*：这项研究的新颖性和意义在于，它将进一步细化我们对大脑皮质中视觉图像处理网络如何相互作用的理解。

OBJECTIVE: Mounting evidence from behavioural measures, neuroimaging and clinical data has shown that objects and scenes are processed independently and that, counterintuitively, a scene can be categorized without the need to recognize any of its constituent objects. The goal of this research program is to examine the relationship between object and scene processing and, in particular, the contribution of object-selective cortical areas to scene processing and their corollary. My laboratory has demonstrated that non-invasive neuromodulation of object-selective cortex with transcranial magnetic stimulation (TMS) has remote effects across the brain in scene processing regions and behaviourally, it alters our ability to perceive scenes. This observation suggests for the first time that object and scene processing may not be as independent as previously thought but might instead involve mutual connections. In the proposed research program I will assess the functional connectivity of object-preferential cortex on scene perception and scene-preferential cortex on object perception at both the behavioural and neural level. ******SCIENTIFIC APPROACH: I will use several complementary methods, including functional magnetic resonance imaging (fMRI), functionally-guided TMS, and behavioural measures. I propose three main experiments to address the following questions: ******1. What level of semantic coding is performed in object-preferential and scene-preferential cortices? When does it occur? I will perform offline TMS to object-preferential and scene-preferential cortices to determine the contribution of these regions to levels of semantic coding of objects and scenes. Subsequently, online TMS will be performed to determine the temporal coding in the neuromodulated target object and scene regions. ***2. What is the functional connectivity between object and scene processing cortical areas? I will use a consecutive TMS-fMRI design to measure scene- and object-induced BOLD signal in the object and scene-preferential cortical networks following offline low frequency repetitive TMS to object and scene-preferential cortex. In a similar paradigm, I will apply TMS online during fMRI scanning using an MR-compatible coil to observe real-time neuromodulatory effects in remote regions to the stimulation site. ***3. What is the anatomical connectivity between the lateral occipital (LO) object-selective area and scene-selective cortex? I will use diffusion tensor imaging (DTI) to determine white matter connectivity between these areas.******NOVELTY AND SIGNIFICANCE: This novelty and significance of this research is that it will further refine our understanding of how visual image processing networks in the cortex interact.