Neural field model to reconcile structure with function in primary visual cortex.
Neural field model to reconcile structure with function in primary visual cortex.
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DOI：
10.1371/journal.pcbi.1005821
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发表时间：
2017-10
影响因子：
4.3
通讯作者：
Chavane F
中科院分区：
文献类型：
--
作者：
Rankin J;Chavane F
初级视皮层（V1）中的电压敏感染料成像实验表明，局部定向视觉刺激在刺激视网膜定位足迹内引起稳定的定向选择性激活。皮层激活动态地延伸远远超出视网膜定位足迹，但周边传播保持非选择性-一个令人惊讶的发现，鉴于一些解剖功能研究显示的方向特异性的远程连接。在这里，我们使用一个计算模型来研究这种明显的差异，通过研究预期的人口反应，使用已知的已发表的解剖学约束。在一个具有多个亚群编码方向的平面神经场模型中，模拟了输入驱动的局域态动力学。现实的连接配置文件具有控制远程连接的聚类和它们的取向偏差的参数。我们发现解剖学相关的参数范围和方向选择性激活的急剧衰减之间存在大量重叠，这与成像实验一致。通过这种方式，我们的研究调和了报告的长距离连接的方向偏好与方向选择性神经活动的功能表达。我们的研究结果表明，这种急剧的衰减是偶然的三个因素，即远程连接是足够的扩散，这些连接的方向偏置是在一个中间范围（与解剖学一致），并通过抑制的兴奋是充分平衡。相反，我们的建模结果预测，抑制强度降低，虚假的方向选择性激活可以通过长距离的横向连接产生。此外，如果横向连接的方向偏差非常强，或者如果抑制特别弱，则网络的运行接近于不稳定，导致无限的皮层激活。光学成像技术可以揭示皮层激活的动态模式，这些模式编码低水平的视觉特征，如位置和方向，这些特征由前馈投射、复发性和长距离皮层内连接形成。解剖学研究已经描述了皮质内连接的特征，然而，根据这些数据预测诱发活动如何在皮质上传播并非易事。事实上，仍然有一个明显的冲突之间的报告方向偏见的皮层连接，和成像研究的传播皮层活动。我们的研究调和结构（解剖）与功能（诱发活动），使用动态神经场模型，预测皮质激活的动态设置的灵感和参数匹配到现有的解剖数据。
Voltage-sensitive dye imaging experiments in primary visual cortex (V1) have shown that local, oriented visual stimuli elicit stable orientation-selective activation within the stimulus retinotopic footprint. The cortical activation dynamically extends far beyond the retinotopic footprint, but the peripheral spread stays non-selective—a surprising finding given a number of anatomo-functional studies showing the orientation specificity of long-range connections. Here we use a computational model to investigate this apparent discrepancy by studying the expected population response using known published anatomical constraints. The dynamics of input-driven localized states were simulated in a planar neural field model with multiple sub-populations encoding orientation. The realistic connectivity profile has parameters controlling the clustering of long-range connections and their orientation bias. We found substantial overlap between the anatomically relevant parameter range and a steep decay in orientation selective activation that is consistent with the imaging experiments. In this way our study reconciles the reported orientation bias of long-range connections with the functional expression of orientation selective neural activity. Our results demonstrate this sharp decay is contingent on three factors, that long-range connections are sufficiently diffuse, that the orientation bias of these connections is in an intermediate range (consistent with anatomy) and that excitation is sufficiently balanced by inhibition. Conversely, our modelling results predict that, for reduced inhibition strength, spurious orientation selective activation could be generated through long-range lateral connections. Furthermore, if the orientation bias of lateral connections is very strong, or if inhibition is particularly weak, the network operates close to an instability leading to unbounded cortical activation. Optical imaging techniques can reveal the dynamical patterns of cortical activation that encode low-level visual features like position and orientation, which are shaped by both feed-forward projections, recurrent and long-range intra-cortical connections. Anatomical studies have characterized intra-cortical connections, however, it is non-trivial to predict from this data how evoked activity might spread across cortex. Indeed, there remains an apparent conflict between the reported orientation bias of cortical connections, and imaging studies on the propagation of cortical activity. Our study reconciles structure (anatomy) with function (evoked activity) using a dynamic neural field model that predicts the dynamics of cortical activation in a setting both inspired by and parametrically matched to the available anatomical data.
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影响因子：
2.5
作者：
BRAITENBERG, V
通讯作者：
BRAITENBERG, V
DOI：
10.1098/rstb.2000.0769
发表时间：
2001-03-29
影响因子：
6.3
作者：
Bressloff, PC;Cowan, JD;Wiener, MC
通讯作者：
Wiener, MC
影响因子：
3
作者：
Chavane F;Sharon D;Jancke D;Marre O;Frégnac Y;Grinvald A
通讯作者：
Grinvald A
影响因子：
2.5
作者：
Chemla, Sandrine;Chavane, Frederic
通讯作者：
Chavane, Frederic
影响因子：
1.2
作者：
Blumenfeld B;Bibitchkov D;Tsodyks M
通讯作者：
Tsodyks M