Kumaran Dharshan, Maguire Eleanor A
Wellcome Department of Imaging Neuroscience, Institute of Neurology, University College London, London WC1N 3BG, United Kingdom.
J Neurosci. 2005 Aug 3;25(31):7254-9. doi: 10.1523/JNEUROSCI.1103-05.2005.
The hippocampus is widely accepted to play a pivotal role in memory. Two influential theories offer competing accounts of its fundamental operating mechanism. The cognitive map theory posits a special role in mapping large-scale space, whereas the relational theory argues it supports amodal relational processing. Here, we pit the two theories against each other using a novel paradigm in which the relational processing involved in navigating in a city was matched with similar navigational and relational processing demands in a nonspatial (social) domain. During functional magnetic resonance imaging, participants determined the optimal route either between friends' homes or between the friends themselves using social connections. Separate brain networks were engaged preferentially during the two tasks, with hippocampal activation driven only by spatial relational processing. We conclude that the human hippocampus appears to have a bias toward the processing of spatial relationships, in accordance with the cognitive map theory. Our results both advance our understanding of the nature of the hippocampal contribution to memory and provide insights into how social networks are instantiated at the neural level.
海马体在记忆中发挥关键作用已被广泛认可。两种有影响力的理论对其基本运作机制给出了相互竞争的解释。认知地图理论认为海马体在绘制大规模空间地图方面具有特殊作用，而关系理论则认为它支持无模态关系处理。在此，我们使用一种新颖的范式让这两种理论相互较量，在该范式中，城市导航中涉及的关系处理与非空间（社交）领域中类似的导航和关系处理需求相匹配。在功能磁共振成像过程中，参与者利用社交关系确定朋友家之间或朋友自身之间的最佳路线。在这两项任务中，分别有不同的脑网络被优先激活，海马体的激活仅由空间关系处理驱动。我们得出结论，根据认知地图理论，人类海马体似乎偏向于处理空间关系。我们的研究结果既推进了我们对海马体对记忆贡献本质的理解，也为社交网络在神经层面是如何形成的提供了见解。
