Neural Mechanisms of Hierarchical Planning in a Virtual Subway Network.
Neural Mechanisms of Hierarchical Planning in a Virtual Subway Network.
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DOI：
10.1016/j.neuron.2016.03.037
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发表时间：
2016-05-18
期刊：
影响因子：
16.2
通讯作者：
Summerfield C
中科院分区：
文献类型：
--
作者：
Balaguer J;Spiers H;Hassabis D;Summerfield C
规划允许组织行动以追求未来的目标。然而，在自然环境中，对多种可能的未来状态进行规划会产生高昂的计算成本。为了有效地表示计划，状态可以分层地聚集到“上下文”中。例如，将地铁网络的旅程表示为一系列单独的状态（车站）比编码一系列上下文（线路）和上下文切换（线路变化）的成本更高。在这里，我们使用功能性大脑成像，要求人类在虚拟地铁网络中执行规划任务。行为分析表明，人类执行的是分层组织的计划。背内侧前额叶皮层和前运动皮层的大脑活动与分层计划表示的成本和这些区域中独特的神经信号信号上下文和上下文切换成比例。这些结果表明，人类使用尾部前额叶结构网络来表示分层计划。人类以分层方式表示计划，在上下文和状态上分层计划的复杂性编码在尾侧前额叶皮层中腹内侧前额叶皮层和海马体编码与目标状态的接近度当前上下文可以从背内侧前额叶皮层解码为了有效地表示计划，世界的状态可以分层地聚集到“上下文”中。巴拉格尔等人。研究表明，当人类在虚拟地铁环境中导航时，功能磁共振成像信号编码了分层计划的复杂性。
Planning allows actions to be structured in pursuit of a future goal. However, in natural environments, planning over multiple possible future states incurs prohibitive computational costs. To represent plans efficiently, states can be clustered hierarchically into “contexts”. For example, representing a journey through a subway network as a succession of individual states (stations) is more costly than encoding a sequence of contexts (lines) and context switches (line changes). Here, using functional brain imaging, we asked humans to perform a planning task in a virtual subway network. Behavioral analyses revealed that humans executed a hierarchically organized plan. Brain activity in the dorsomedial prefrontal cortex and premotor cortex scaled with the cost of hierarchical plan representation and unique neural signals in these regions signaled contexts and context switches. These results suggest that humans represent hierarchical plans using a network of caudal prefrontal structures. Humans represent plans in a hierarchical fashion, over contexts as well as states Hierarchical plan complexity is encoded in caudal prefrontal cortex Ventromedial prefrontal cortex and hippocampus encode proximity to a goal state The current context can be decoded from the dorsomedial prefrontal cortex To represent plans efficiently, states of the world can be clustered hierarchically into “contexts”. Balaguer et al. show that as humans navigate a virtual subway environment, fMRI signals encode the complexity of a hierarchical plan.