Beijing Key Lab of Learning and Cognition, School of Psychology, Capital Normal University, China.
State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, China.
Neuroscience. 2018 Oct 15;390:256-264. doi: 10.1016/j.neuroscience.2018.08.024. Epub 2018 Sep 1.
We aimed to investigate the role of dorsal and ventral visual systems in rapid naming of simple Chinese characters. Twenty college students (10 female; M = 22.5 years) were required to covertly read a character- and a cross-matrix during an fMRI experiment. A basic prosaccade and a prosaccade-naming task were also performed to confirm the functional significance of the findings. The results of whole brain analysis showed that both dorsal and ventral visual systems were activated in the character-matrix reading. The cross-matrix scanning elicited weaker activation in the left middle frontal gyrus, superior temporal gyrus, and ventral occipitotemporal cortex. Next, whereas both top-down and bottom-up effective connectivities (ECs) were found between these two systems in the character-matrix reading, only top-down ECs were observed in the cross-matrix scanning. Moreover, in the character-matrix reading, we found a negative correlation between the reaction time of naming in the prosaccade-naming task and the EC strength from visual word form area to superior temporal gyrus and a positive correlation between the reaction time in the basic prosaccade task and the EC strength from middle frontal gyrus to intraparietal sulcus. The cross-matrix scanning did not show any brain-behavior relationship. These results suggest that while the dorsal visual system is mainly engaged in eye-movement control, the ventral system is associated more with orthographic processing and orthography-phonology mapping.
我们旨在探究中文简体字快速命名中背侧和腹侧视觉系统的作用。二十名大学生（10 名女性；平均年龄 22.5 岁）在 fMRI 实验中被要求在字符和交叉矩阵之间进行隐蔽阅读。还进行了基本的 prosaccade 和 prosaccade-naming 任务，以确认发现的功能意义。全脑分析的结果表明，背侧和腹侧视觉系统都在字符矩阵阅读中被激活。在交叉矩阵扫描中，左侧额中回、颞上回和腹侧枕颞皮质的激活较弱。接下来，虽然在字符矩阵阅读中发现这两个系统之间存在自上而下和自下而上的有效连通性（EC），但在交叉矩阵扫描中只观察到自上而下的 EC。此外，在字符矩阵阅读中，我们发现 prosaccade-naming 任务中命名反应时间与从视觉词形区到颞上回的 EC 强度之间存在负相关，而基本 prosaccade 任务中的反应时间与从中额回到顶内沟的 EC 强度之间存在正相关。在交叉矩阵扫描中没有发现任何脑-行为关系。这些结果表明，背侧视觉系统主要参与眼球运动控制，而腹侧系统则与正字法处理和正字法-语音映射更相关。
