Iaria Giuseppe, Arnold Aiden E G F, Burles Ford, Liu Irene, Slone Edward, Barclay Sarah, Bech-Hansen Torben N, Levy Richard M
Department of Psychology and Hotchkiss Brain Institute, NeuroLab University of Calgary 2500 University Drive NW, Calgary, Alberta, Canada, T2N 1N4; Alberta Children's Hospital Research Institute, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada, T2N 1N4.
Hippocampus. 2014 Nov;24(11):1364-74. doi: 10.1002/hipo.22317. Epub 2014 Jul 4.
Developmental topographical disorientation (DTD) is a newly discovered cognitive disorder in which individuals experience a lifelong history of getting lost in both novel and familiar surroundings. Recent studies have shown that such a selective orientation defect relies primarily on the inability of the individuals to form cognitive maps, i.e., mental representations of the surrounding that allow individuals to get anywhere from any location in the environment, although other orientation skills are additionally affected. To date, the neural correlates of this developmental condition are unknown. Here, we tested the hypothesis that DTD may be related to ineffective functional connectivity between the hippocampus (HC; known to be critical for cognitive maps) and other brain regions critical for spatial orientation. A group of individuals with DTD and a group of control subjects underwent a resting-state functional magnetic resonance imaging (rsfMRI) scan. In addition, we performed voxel-based morphometry to investigate potential structural differences between individuals with DTD and controls. The results of the rsfMRI study revealed a decreased functional connectivity between the right HC and the prefrontal cortex (PFC) in individuals with DTD. No structural differences were detected between groups. These findings provide evidence that ineffective functional connectivity between HC and PFC may affect the monitoring and processing of spatial information while moving within an environment, resulting in the lifelong selective inability of individuals with DTD to form cognitive maps that are critical for orienting in both familiar and unfamiliar surroundings.
发育性地形定向障碍（DTD）是一种新发现的认知障碍，患者在陌生和熟悉的环境中都有终生迷路的经历。最近的研究表明，这种选择性定向缺陷主要源于个体无法形成认知地图，即对周围环境的心理表征，从而使个体能够从环境中的任何位置到达任何地方，不过其他定向技能也会受到额外影响。迄今为止，这种发育状况的神经关联尚不清楚。在此，我们检验了一个假设，即DTD可能与海马体（HC，已知对认知地图至关重要）和其他对空间定向至关重要的脑区之间的功能连接无效有关。一组患有DTD的个体和一组对照受试者接受了静息态功能磁共振成像（rsfMRI）扫描。此外，我们进行了基于体素的形态学测量，以研究DTD患者与对照组之间潜在的结构差异。rsfMRI研究结果显示，DTD患者右侧HC与前额叶皮质（PFC）之间的功能连接减少。两组之间未检测到结构差异。这些发现提供了证据，表明HC与PFC之间的功能连接无效可能会影响在环境中移动时对空间信息的监测和处理，导致DTD患者终生选择性地无法形成对在熟悉和陌生环境中定向至关重要的认知地图。
