Cortical Areas and Neural Connections Underlying Scene Processing

描述(申请人提供)：在人类受试者中，神经成像和其他技术表明，视觉皮质的不同区域对不同类型的视觉刺激有特定的反应。例如，面孔会选择性地激活一组特定的大脑区域，而场景则会激活另一组区域，包括名为“PPA”、“TOS”和“RSC”的区域。了解对环境中场景做出反应的区域的功能和联系，将为正常受试者导航和感知视觉场景所使用的总体策略提供基本的见解。此外，这些皮质中枢的大脑损伤与许多神经综合征有关，包括肢体失认症、导航失认症和威廉姆斯综合征。由于可用于研究人类受试者的技术不能揭示这一网络功能的所有基本神经机制，动物模型为理解环境感知的神经基础提供了必要的手段。这项提议的目标之一就是提供这样一个模式。我们的第一个目标(目标1)是通过使用功能磁共振成像(FMRI)在非人类灵长类动物中证明三个场景响应区的存在，然后对皮质图进行定量比较，以表明场景响应区在人类和猴子之间是一致的。根据我们的初步数据，我们预计这一目标将圆满完成。这将使得能够使用经典的微创技术(例如神经追踪器)来澄清场景处理的特定电路(目标2)。三种基于核磁共振的技术(包括新方法)将被用来追踪灵长类动物这三个区域之间的神经联系。多种追踪技术的使用将提供有关皮质连接的综合信息，并在一个共同的系统中验证每一种技术。目标2还将回答有关神经场景处理的神经连接的具体问题：这三个区域是否相互连接，和/或与背侧(什么)流连接，和/或以多突触方式连接到海马体，在海马体中，位置编码神经元是众所周知的？在目标#3中，我们将使用fMRI来跟踪感觉驱动的信息(在目标#1/2中)到灵长类皮质中更高的大脑水平，这些信息是在场景识别任务中驱动的。在人类中，相同的识别任务在大脑皮层区域产生了强大的活动，与面部识别任务产生的活动不同。我们的假设是，当猴子执行相同的识别任务时，fMRI活动将在相应的皮质区域产生。成功完成所有AIMS将使用不同的基于MRI的方法来展示警觉灵长类动物的场景处理网络，从感觉驱动到任务驱动，以及这些区域之间的联系。 与公共健康相关：拟议的研究将确定参与视觉场景处理的大脑区域和连接。这种大脑信息对正常视力至关重要，在多种神经综合征和发育障碍中都会受到干扰，包括威廉姆斯综合征和导航失认。

DESCRIPTION (provided by applicant): In human subjects, neuroimaging and other techniques have revealed that different regions of visual cortex respond specifically to distinct types of visual stimuli. For instance, faces selectively activate one specific set of brain regions, and scenes activate a different set, including the areas named 'PPA,' 'TOS' and 'RSC'. Understanding the function and connections of the regions that respond to scenes in the environment will provide fundamental insights about the overall strategies used by normal subjects to navigate and to perceive visual scenes. Moreover, brain damage to each of these cortical centers has been implicated in numerous neurological syndromes, including prosopagnosia, navigation agnosia and Williams Syndrome. Because the techniques available to study human subjects cannot reveal all of the basic neural mechanisms underlying the function of this network, animal models provide an essential means to understand the neural basis of the environmental perception. One goal of this proposal is to provide such a model. Our first goal (Aim #1) is to demonstrate the existence of three scene-responsive areas by using functional magnetic imaging (fMRI) in non-human primates, then to compare the cortical maps quantitatively, to show that the scene-responsive regions correspond across humans and monkeys. Based on our preliminary data, we anticipate successful completion of this aim. This will enable the use of classical, minimally invasive techniques (e.g. neural tracers) to clarify the specific circuits of scene processing (Aim #2). Three MRI-based techniques (including novel methods) will be used to trace the neural connections between each of these three areas in primates. The use of multiple tracing techniques will furnish integrated information about the cortical connections, and validate each of the techniques in a common system. Aim #2 will also answer specific questions about the neural connections underlying neural scene processing: do these three areas connect with each other, and/or with the dorsal (the 'what') stream, and/or multi-synaptically to the hippocampus, in which 'place-coding' neurons are well-known? In Aim #3, we will use fMRI to track sensory-driven information (in Aims #1/2) to higher brain levels in primate cortex, which are driven during scene recognition tasks. In humans, an identical recognition task produced robust activity in the cortical patches distinct from those produced in a face recognition task. Our hypothesis is that fMRI activity will be produced in homologous cortical areas, when monkeys are performing an equivalent recognition task. Successful completion of all aims will use different MRI-based methods to demonstrate a scene- processing network in alert primates, ranging from sensory-driven to task-driven, and the connections between these areas. PUBLIC HEALTH RELEVANCE: The proposed research will identify brain regions and connections that are involved in the processing of visual scenes. Such brain information is crucial in normal vision, and it is disturbed in multiple neurological syndromes and developmental disorders, including Williams syndrome and navigation agnosia.