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题名	“大范围首先”拓扑视知觉加工的神经通路研究
作者	孟千力
学位类别	博士
答辩日期	2011-05
授予单位	中国科学院研究生院
授予地点	北京
导师	马原野
关键词	爱耳浪根纲领 拓扑性质 情绪 双眼竞争 经颅磁刺激 洞
其他题名	the neural mechanism of global-first topological perception
学位专业	神经生物学
中文摘要	视觉从哪里开始？不同于传统的“由局部到整体”理论，“大范围首先”理论提出视知觉是从整体到局部。克莱因的爱耳浪根纲领提出各种形状性质可以由不同层次的几何学，即由欧几里得几何学、仿射几何学、射影几何学和拓扑学来加以描述。根据几何不变性，最为稳定和大范围的是拓扑性质。在视知觉同样有一个与其十分相吻合的知觉功能层次，其中拓扑性质知觉较之其它局部几何性质知觉，是最基本，最早期的知觉，知觉物体是从抽提拓扑性质开始的。然而对于拓扑性质知觉加工的神经通路的研究还不够完善。目前的脑成像研究发现拓扑性质知觉的神经表达位于前颞叶，但是在经典的视觉通路中，前颞叶位于视觉腹侧通路的最末端，是物体识别加工的高级区域。然而大量的行为实验均表明被加工于前颞叶的拓扑性质知觉是视知觉的最初期阶段，其敏感性和反应时上均优先于局部性质，这似乎是矛盾的。那么对于拓扑性质知觉的加工，是否不通过传统的经典视觉通路，而是经由其他的通路加工呢？本文就这个问题展开研究。 有研究表明除了经典的视觉通路，还有一条"古老"的皮层下通路主要负责快速加工和情绪相关的信息. 这条通路绕开初级视觉皮层，由上丘，枕核和杏仁核组成。如果拓扑性质知觉也通过这条通路加工，那么情绪的加工应该会干扰拓扑性质知觉加工。我们的研究表明，不管是意识上，还是意识下的恐惧情绪都可以稳定的干扰拓扑性质知觉，但是对于其他局部几何性质知觉却没有影响。进一步的脑成像实验表明，杏仁核确实参与了拓扑性质知觉的加工。 洞的个数是拓扑不变量之一。洞可以作为一种整体性质被抽提出来。我们的实验发现：相对于非洞的图形，有洞的图形更容易突破双眼竞争中产生的抑制，到达意识上而被知觉到。采用经颅磁刺激技术抑制初级视觉皮层的功能，实验结果发现非洞图形的辨认会受到影响，但是有洞图形的辨认不会受到干扰，从而说明了洞的加工是不主要依赖于初级视觉皮层的。 本文的实验结果都一致支持拓扑性质知觉的加工不依赖于初级视觉皮层，但是要直接证明拓扑性质知觉的加工是通过皮层下通路，还需要更多的实验验证。
英文摘要	Where does vision begin? Competing with the mainstream view of "local to global", the topological approach emphasizes a "global-first" approach to perceptual organization by claiming that global topological invariants are extracted at the very beginning of visual processing. According to the levels of structural stability, a functional hierarchy in which the relative salience or priority in the perception of different geometric properties is remarkably consistent with the hierarchy of geometries (Euclidean, affine, projective and topological property) stratified by Klein's Erlangen Program. In the functional hierarchies, the topological property is the most stable and basic property that is the first to be extracted by the visual system to form basic constraints on object coding. However, it is still an unsolved question that how the topological perception is processed by the visual system. Some fMRI studies find the robust activation of anterior temporal lobe (ATL) responding to the topological perception. It seems like a contradiction that the beginning of visual perception is processed by the terminator of the typical visual pathway. In this paper, we aim to find out whether the topological perception is processed by the typical visual pathway or the other fast pathway. There is a phylogenetically older subcortical visual system including superior colliculus (SC), pulvinar and amygdala is found to process the less detailed but faster processing about emotion, bypassing the primary visual cortex. If topological perception is processed by this subcortical pathway, we suppose that emotion will interfere with topological perception. Our studies systematically and consistently demonstrated that fear emotion with or without conscious awareness both interrupted the topological perception, but not the perception of the other geometrical properties. The fMRI results further illustrated that amygdala actually took part in the topological perception processing.Hole is one of the basic topological properties. In the binocular rivalry study, we found that compared with no-hole, the hole property took less time to overcome the suppression induced by the dominate flash visual pattern and to be perceived with conscious awareness. Furthermore, we proceeded to apply Transcranial magnetic stimulation (TMS) on V1 to directly suppress the neural activation of V1, we found that the suppresstion did impair the performance of the discrimination of no-hole, but not hole. The results of TMS study provided a powerful demonstration to confirm that the hole perception could be processed indepent of the primary visual cortex. All the experiments consistently supported that the topological perception could be processed bypassing the primary visual cortex and maybe processed by the subcortical pathway. However, more experiments are needed to investigate it.
语种	中文
公开日期	2013-04-24
内容类型	学位论文
源URL	[http://159.226.149.42:8088/handle/152453/7392]
专题	昆明动物研究所_认知障碍病理学
推荐引用方式 GB/T 7714	孟千力. “大范围首先”拓扑视知觉加工的神经通路研究[D]. 北京. 中国科学院研究生院. 2011.

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