边界促进空间导航的认知神经机制

Cognitive neural mechanism of boundary processing in spatial navigation

边界是指在人的视野中占据较大比例,且具有立体拓展平面的障碍物,对于人类和动物的空间导航行为具有极大的促进作用。认知发展研究发现儿童早期(1岁半~2岁)通过加工边界的空间几何结构实现物体定位,并且随着年龄的发展逐渐学会利用边界的高度信息(3.1岁~4.7岁)、长度信息(4~5岁)、视觉阻碍性信息(5岁)等完成空间导航。基于这些认知过程,神经影像学研究主要以成人为研究被试,发现大脑中的内侧颞叶和顶叶脑区在边界加工中有着不同功能作用。具体而言,边界的空间几何结构及构成要素(高度、长度和角度)体位置的学习和提取则由海马负责。但是,仍存在一些研究问题值得未来深入S探c讨i。e第n一c,e拓展深化边界促进与后顶叶之间的功能交互。第三,密切关注大脑对场地边界与场地中心编码的心理或神经表征的区别和联系。第四,重点考察阿尔兹海默症有关基因易感人群在基于边界导航的行为受损情况。最后,延伸探讨边界在长时记忆、时间知觉、视觉空间、社交网络等领域的影响机制。

Boundaries are obstacles with extended surfaces in the spatial environment and contribute significantly to the spatial navigation for humans and animals.Cognitive developmental studies found that children could reorient successfully by using the geometry of the boundary when they were disoriented at the age of 1.5~2 years old,and gradually using the vertical information until they were 3.1~4.7 years old,length information until the age of 4~5,and visual opaqueness information until the age of 5 years old in navigation.In addition,neuroimaging studies in adults have found that the medial temporal lobe and parietal lobe play different roles in boundary processing.Specifically,the boundary geometry and constituent elements were represented in the parahippocampal place area and the retrosplenial complex.Furthermore,the navigational affordance for a boundary was represented in the occipital parietal area.Finally,encoding and retrieval of the boundary-based object’s location were associated with the hippocampus.Several issues are unaddressed that should be investigated in future.First,future studies should explore the comprehensive cognitive processes of boundary-based navigation and its development trajectory.Second,further research could explore the functional interaction between the medial temporal lobe and posterior parietal cortex.Third,we could pay attention to the distinctions and associations between the cognitive neural mechanisms of the boundary and geometry center encoding.Forth,further study could investigate specific behavioral impairment of boundary-based navigation in individuals with at-genetic-risk Alzheimer’s disease.Finally,we could about the boundary influence mechanisms in long-term memory,time estimation,visual space,and social networks.