2003-08-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/700372摘要：「知覺群聚現象」（perceptual grouping）是視覺系統的重要功能之一，意指人們會很自然地整合影像的組成部分，以形成對該影像的新知覺。雖然文獻中已經有不少行為取向的研究，但知覺群聚現象的神經生理基礎仍不明朗。近來，知覺群聚現象的神經生理研究正逐漸累積中，在過去兩年來至少有數篇期刊論文與不少學術會議報告致力於此方面的研究。 本計畫將提出一個知覺群聚的工作模型（working model）：根據文獻裡的資料顯示，大腦皮質V1/V2負責處理刺激情境對知覺群聚的影響，而已知大腦皮質V1/V2的神經細胞主要的功能在於處理刺激的局部成分。這意味著該處的神經細胞有增益性的互動始能產生情境效果。V1神經細胞互動後所產生的調節反應，由大腦皮質V4的神經細胞接收，並整合V1神經細胞所送來的局部訊息以偵測影像中是否包含曲線。大腦皮質的側枕葉綜合體（lateral occipital complex，簡稱LOC）將曲線整合以形成整體知覺，並將影像裡的目標物體與背景分離。本計畫的主要目的在於檢驗上述的知覺群聚的工作模型，亦即檢視在視覺訊息處理過程的腹側管道（ventral stream，包含V1、<br> Abstract: Perceptual grouping refers to the phenomenon that a human observer integrates image components together to form a percept of a new object. Perceptual grouping is an essential function for the visual system. However, while there are many behavior studies on perceptual grouping, the neurophysiological basis of perception grouping is unclear. Lately, there is a growing interest in the neurophysiology of perceptual grouping: there were several journal articles on this issue in the past two years and even more conference reports. From evidence in the literature, a working model for perceptual grouping is proposed here. The contextual effects in brain area V1/V2 imply a facilitative interaction among neurons responding to local elements. A neuron in the brain area V4 picks up the local response modulation in V1 created by the facilitative interaction and is able to detect curves in an image. The area LOC (lateral occipital complex) links curves together to form a global percept and separate the target object from the rest of the image. This project will test the working model by determining the role of each brain area in the ventral stream (V1, V2 and LOC) in perceptual grouping. A set of stimuli that emphasize certain aspects of perceptual grouping will be used. These stimuli should produce a differential response in the target brain areas. The blood oxygenation level dependent (BOLD) activation will be measured in the human occipital cortex to those stimuli with function magnetic resonance imaging technique (fMRI). The orientation and chromaticity tuning functions for perceptual grouping in ventral brain areas will be measured and compared with psychophysics results. In addition, the BOLD activation to certain aspect of perceptual grouping, such as local interaction, curvature formation and figure-ground segregation, and the response strength as a function of signal-to-noise ratio in an image will be measured. These results will help identify the role of each brain areas. Finally, we will explore the possible involvement of the dorsal stream in perceptual grouping. The existence of which may lead to a future project.大腦皮質磁核共振造影神經生理NeuroimagingBOLDperceptual groupingglass patternfMRIcontour integration