Ekstrom Arne D, Kahana Michael J, Caplan Jeremy B, Fields Tony A, Isham Eve A, Newman Ehren L, Fried Itzhak
Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454, USA.
Nature. 2003 Sep 11;425(6954):184-8. doi: 10.1038/nature01964.
Place cells of the rodent hippocampus constitute one of the most striking examples of a correlation between neuronal activity and complex behaviour in mammals. These cells increase their firing rates when the animal traverses specific regions of its surroundings, providing a context-dependent map of the environment. Neuroimaging studies implicate the hippocampus and the parahippocampal region in human navigation. However, these regions also respond selectively to visual stimuli. It thus remains unclear whether rodent place coding has a homologue in humans or whether human navigation is driven by a different, visually based neural mechanism. We directly recorded from 317 neurons in the human medial temporal and frontal lobes while subjects explored and navigated a virtual town. Here we present evidence for a neural code of human spatial navigation based on cells that respond at specific spatial locations and cells that respond to views of landmarks. The former are present primarily in the hippocampus, and the latter in the parahippocampal region. Cells throughout the frontal and temporal lobes responded to the subjects' navigational goals and to conjunctions of place, goal and view.
啮齿动物海马体中的位置细胞是哺乳动物神经元活动与复杂行为之间相关性最显著的例子之一。当动物穿过其周围环境的特定区域时,这些细胞会提高其放电频率,提供一个依赖于环境的环境地图。神经影像学研究表明海马体和海马旁区域与人类导航有关。然而,这些区域也对视觉刺激有选择性反应。因此,目前尚不清楚啮齿动物的位置编码在人类中是否有同源物,或者人类导航是否由不同的、基于视觉的神经机制驱动。当受试者探索和导航一个虚拟城镇时,我们直接记录了人类颞叶内侧和额叶中的317个神经元的活动。在这里,我们提供了证据,证明人类空间导航存在一种神经编码,该编码基于在特定空间位置做出反应的细胞以及对地标视图做出反应的细胞。前者主要存在于海马体中,后者存在于海马旁区域。额叶和颞叶中的细胞对受试者的导航目标以及位置、目标和视图的组合做出反应。