Does the entorhinal cortex use the Fourier transform?
Does the entorhinal cortex use the Fourier transform?
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DOI：
10.3389/fncom.2013.00179
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发表时间：
2013
影响因子：
3.2
通讯作者：
Ji X
中科院分区：
文献类型：
--
作者：
Orchard J;Yang H;Ji X
当动物在其空间环境中占据以六角网格模式组织的位置时，内嗅皮层(EC)中的一些神经元发生火灾。位置细胞也被观察到，只有当动物占据环境的特定区域时才会放电。这两种类型的细胞都表现出theta周期调制，在4-12赫兹范围内发射脉冲。网格细胞发射相对于theta循环进动的动作电位的爆发，这种现象被称为“theta进动”。已经提出了各种模型来解释这些现象，以及它们与导航的关系。其中最有希望的是振荡器干扰模型。Welday等人提出的振荡器组模型。展示了所有这些特征。然而，他们的模拟是基于理论振荡器，而不是完全用尖峰神经元实现的。我们通过多种方式扩展他们的工作。首先，我们将振荡器放在频域中，并根据傅立叶理论对模型进行重新表述。其次，从这个角度来看，实现空间地图需要进行分工：位置与地图布局。动物的位置被编码在振荡器的相位中，而空间地图形状被隐含地编码在振荡器和读出节点之间的连接的权重中。第三，它揭示了振荡器的相位都需要在频域内符合线性关系。第四，我们使用尖峰泄漏积分与点火(LIF)神经元实现了EC的部分模型。第五，我们设计了新的耦合机制，受到全局相位约束的启发，并证明了它们能够保持尖峰神经振荡器保持一致的构型。我们的模型演示了位胞、格胞和位相进动。傅立叶模型还为未来的研究提供了方向，例如整合感觉反馈以对抗漂移，或者解释为什么网格细胞存在。
Some neurons in the entorhinal cortex (EC) fire bursts when the animal occupies locations organized in a hexagonal grid pattern in their spatial environment. Place cells have also been observed, firing bursts only when the animal occupies a particular region of the environment. Both of these types of cells exhibit theta-cycle modulation, firing bursts in the 4–12 Hz range. Grid cells fire bursts of action potentials that precess with respect to the theta cycle, a phenomenon dubbed “theta precession.” Various models have been proposed to explain these phenomena, and how they relate to navigation. Among the most promising are the oscillator interference models. The bank-of-oscillators model proposed by Welday et al. exhibits all these features. However, their simulations are based on theoretical oscillators, and not implemented entirely with spiking neurons. We extend their work in a number of ways. First, we place the oscillators in a frequency domain and reformulate the model in terms of Fourier theory. Second, this perspective suggests a division of labor for implementing spatial maps: position vs. map layout. The animal's position is encoded in the phases of the oscillators, while the spatial map shape is encoded implicitly in the weights of the connections between the oscillators and the read-out nodes. Third, it reveals that the oscillator phases all need to conform to a linear relationship across the frequency domain. Fourth, we implement a partial model of the EC using spiking leaky integrate-and-fire (LIF) neurons. Fifth, we devise new coupling mechanisms, enlightened by the global phase constraint, and show they are capable of keeping spiking neural oscillators in consistent formation. Our model demonstrates place cells, grid cells, and phase precession. The Fourier model also gives direction for future investigations, such as integrating sensory feedback to combat drift, or explaining why grid cells exist at all.
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影响因子：
7.8
作者：
Rolls, Edmund T.;Stringer, Simon M.;Elliot, Thomas
通讯作者：
Elliot, Thomas
DOI：
10.1523/jneurosci.6048-08.2009
发表时间：
2009-06-10
期刊：
The Journal of neuroscience : the official journal of the Society for Neuroscience
影响因子：
--
作者：
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通讯作者：
Lisman JE
影响因子：
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作者：
通讯作者：
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影响因子：
2.9
作者：
Mathis, Alexander;Herz, Andreas V. M.;Stemmler, Martin
通讯作者：
Stemmler, Martin
影响因子：
3.5
作者：
OKEEFE, J;RECCE, ML
通讯作者：
RECCE, ML