运用pRF技术对汉语母语者早期视皮层的研究

发布时间：2018-01-22 15:37

本文关键词： 初级视皮层汉字阅读视网膜皮质拓扑映射神经元群感受野视知觉学习　出处：《华东师范大学》2014年硕士论文　论文类型：学位论文

【摘要】：认知神经科学研究发现,法语和英语母语阅读者的左侧初级视皮层对其母语文字会有选择性的反应,而且激活位置与日常阅读中文字呈现的视野位置相对应。这种特异性产生的机制是可能是视知觉学习,即文字持续刺激阅读所偏向的视野,造成了相应皮层区域的知觉学习。由于阅读从左往右水平书写的现代汉语时,视知觉广度偏向视野的右侧水平子午线,我们根据视网膜与皮质之间的映射关系推测：长期的汉字阅读经验会改变汉语母语者的左侧初级视皮层,尤其是其中表征视野右侧水平子午线的皮层功能甚至结构。但是考虑到汉字相对于字母文字的复杂性与特殊性,汉字阅读可能也需要右侧V1及相对较高级视觉区域的参与。为了研究上述问题,本研究借助功能磁共振成像及神经元群感受野分析技术(population receptive field, pRF),精确地定位了熟练的汉语阅读者的早期视皮层(V1、V2和V3)及其他感兴趣区,并分析了它们的感受野和表面积。统计结果显示,左腹侧V3的皮层表面积和感受野显著大于右腹侧V3,而且左腹侧V3的感受野大小与被试的汉字阅读成绩呈显著正相关。此外,垂直子午线的感受野显著大于水平子午线。而包括V1在内的其他感兴趣区的表面积和感受野大小在左右脑之间均不存在显著差异。这表明双侧V1和左腹侧V3都参与了汉字阅读加工。汉字与字母文字在早期视皮层偏侧化模式上的差异说明,文字阅读具体征用哪些视觉区域取决于文字系统的特征及其视觉加工的要求。
[Abstract]:Cognitive neuroscience studies have found that the left primary visual cortex of French and English native speakers responds selectively to their native language. Moreover, the activation position corresponds to the visual field position of the text in daily reading. This specific mechanism may be visual perceptual learning, that is, the visual field biased by the text continuous stimulation of reading. As a result of reading from left to right level writing modern Chinese visual perception breadth deviates to the right horizontal meridian of the field of vision. According to the mapping relationship between retina and cortex, we speculate that long-term Chinese character reading experience will change the left primary visual cortex of native Chinese speakers. In particular, the cortical function and structure of the horizontal meridian on the right side of the visual field are represented, but the complexity and particularity of Chinese characters relative to alphabetic characters are considered. Chinese character reading may also require the participation of the right V1 and the relatively advanced visual regions. In this study, functional magnetic resonance imaging (fMRI) and neuronal group receptive field analysis were used to study the population receptive field (pRFs). The early visual cortex (V1, V2 and V3) and other regions of interest of the skilled Chinese readers were accurately located, and their receptive fields and surface areas were analyzed. The cortical surface area and receptive field of left ventral V3 were significantly larger than that of right ventral V3, and the size of left ventral V3 was positively correlated with the reading scores of Chinese characters. The receptive field of vertical meridian is significantly larger than that of horizontal meridian, while the surface area and the size of receptive field in other regions of interest, including V1, have no significant difference between the left and right brain. This indicates that bilateral V1 and left ventral V. The differences between Chinese characters and alphabetic characters in the early visual cortex lateralization model were all involved in the processing of Chinese characters. Which visual areas are requisitioned by text reading depends on the characteristics of the character system and the requirements of visual processing.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：B842

【相似文献】