Structure of spontaneous UP and DOWN transitions self-organizing in a cortical network model.
Structure of spontaneous UP and DOWN transitions self-organizing in a cortical network model.
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在皮质网络模型中自发和下向过渡的自发结构。
DOI：
10.1371/journal.pcbi.1000022
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发表时间：
2008-03-07
影响因子：
4.3
通讯作者：
Fukai, Tomoki
中科院分区：
文献类型：
--
作者：
Kang, Siu;Kitano, Katsunori;Fukai, Tomoki
突触可塑性被认为在局部皮层网络的经验依赖性自组织中起着至关重要的作用。在没有感觉刺激的情况下，大脑皮层表现出在UP和DOWN状态之间的自发膜电位转换。为了揭示皮层网络如何发展自发活动，或者相反，自发活动如何结构皮层网络，我们分析了兴奋性和抑制性神经元的循环网络模型的自组织，这是现实的，足以复制上下状态，与尖峰定时依赖可塑性（STDP）。自组织网络中的单个神经元在两态转换中表现出各种各样的时间模式。此外，该模型开发了一个前馈网络结构，产生了不同的剧目的精确序列的UP状态。我们的模型表明，自组织活动很好地类似于自发活动的皮层网络，如果STDP是伴随着修剪弱突触。这些结果表明，两种状态的膜电位转换在局部皮层回路的结构中起着积极的作用。大脑的信息处理主要依赖于神经元回路。因此，阐明大脑回路的结构是理解大脑如何处理信息的关键一步。特别是，大脑皮层占据了灵长类动物和人类大脑的很大一部分，因此局部皮层网络的组织对于高级认知功能的出现至关重要。然而，局部皮层网络的复杂结构和计算在很大程度上仍然未知。在这项研究中，我们调查的神经元布线和活动的自组织与突触可塑性的局部皮层网络模型。突触可塑性描述了神经元对之间的突触如何根据个体对的活动而被修改。在我们的模型中，自组织的不规则活动与睡眠期间观察到的自发皮层活动惊人地相似。此外，这种自主活动包含了各种各样的精确定时的时间序列。局部皮层网络是否能产生如此精确的时间序列，目前在神经科学中还存在争议。睡眠状态下时间序列的自我组织表明，它们可能在学习感官体验和运动技能方面发挥积极作用，睡眠对这些技能至关重要。
Synaptic plasticity is considered to play a crucial role in the experience-dependent self-organization of local cortical networks. In the absence of sensory stimuli, cerebral cortex exhibits spontaneous membrane potential transitions between an UP and a DOWN state. To reveal how cortical networks develop spontaneous activity, or conversely, how spontaneous activity structures cortical networks, we analyze the self-organization of a recurrent network model of excitatory and inhibitory neurons, which is realistic enough to replicate UP–DOWN states, with spike-timing-dependent plasticity (STDP). The individual neurons in the self-organized network exhibit a variety of temporal patterns in the two-state transitions. In addition, the model develops a feed-forward network-like structure that produces a diverse repertoire of precise sequences of the UP state. Our model shows that the self-organized activity well resembles the spontaneous activity of cortical networks if STDP is accompanied by the pruning of weak synapses. These results suggest that the two-state membrane potential transitions play an active role in structuring local cortical circuits. Information processing by the brain relies crucially on neuronal circuits. Therefore, clarifying the structure of the brain circuitry is a crucial step towards understanding how the brain processes information. In particular, the cerebral cortex occupies a large portion of the brain in primates and humans, so the organization of local cortical networks is essential for the emergence of higher cognitive functions. However, the complex structure and computations of local cortical networks remain largely unknown. In this study, we investigate the neuronal wiring and activity self-organizing with synaptic plasticity in a model of local cortical networks. Synaptic plasticity describes how synapses between neuron pairs are modified according to activities of the individual pairs. The irregular activity self-organizing in our model surprisingly resembles the spontaneous cortical activity observed during sleep. Moreover, such an autonomous activity contains a diverse repertoire of precisely timed temporal sequences. Whether local cortical networks produce such precise temporal sequences is currently debated in neuroscience. The self-organization of temporal sequences in the sleep-like state suggests that they may play an active role in learning sensory experiences and motor skills, for which sleep is known to be crucial.
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影响因子：
2.5
作者：
Compte, A;Sanchez-Vives, MV;Wang, XJ
通讯作者：
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