覆盖、连续性与视皮层结构
Coverage, Continuity and Visual Cortical Architecture
摘要：
许多哺乳动物的初级视觉皮层包含了视觉空间的连续表征，并叠加了大致重复的非周期性方位偏好图。最近发现，方位偏好图（OPMs）服从统计规律，这显然是不变性的物种之间广泛分离的真兽类进化。在这里，我们研究是否最突出的模型之一，优化皮质地图，弹性网络（EN）模型，可以重现这种常见的设计。EN模型生成的表示，最佳的贸易刺激空间覆盖和地图的连续性。虽然这个模型已被用于许多研究，没有分析结果的精确布局的预测OPM已获得迄今为止。我们提出了一种数学方法来分析计算EN模型预测的皮质表示，用于刺激位置和方向的联合映射。我们发现，在所有以前研究的制度，预测的OPM布局是完美的周期性。通过EN参数空间的无偏搜索确定了一个新的制度的非周期性的OPM的风车密度低于实验中发现的。在一个极端的限制，非周期性的OPM定量类似实验观察出现。这些布局的稳定性来自于强的非局部相互作用，而不是覆盖连续性妥协。我们的研究结果表明，优化模型的刺激表示占主导地位的非局部抑制性相互作用原则上能够正确预测常见的OPM设计。他们质疑视觉皮层特征表征可以用覆盖连续性妥协来解释。
英文摘要：
The primary visual cortex of many mammals contains a continuous representation of visual space, with a roughly repetitive aperiodic map of orientation preferences superimposed. It was recently found that orientation preference maps (OPMs) obey statistical laws which are apparently invariant among species widely separated in eutherian evolution. Here, we examine whether one of the most prominent models for the optimization of cortical maps, the elastic net (EN) model, can reproduce this common design. The EN model generates representations which optimally trade of stimulus space coverage and map continuity. While this model has been used in numerous studies, no analytical results about the precise layout of the predicted OPMs have been obtained so far. We present a mathematical approach to analytically calculate the cortical representations predicted by the EN model for the joint mapping of stimulus position and orientation. We find that in all previously studied regimes, predicted OPM layouts are perfectly periodic. An unbiased search through the EN parameter space identifies a novel regime of aperiodic OPMs with pinwheel densities lower than found in experiments. In an extreme limit, aperiodic OPMs quantitatively resembling experimental observations emerge. Stabilization of these layouts results from strong nonlocal interactions rather than from a coverage-continuity-compromise. Our results demonstrate that optimization models for stimulus representations dominated by nonlocal suppressive interactions are in principle capable of correctly predicting the common OPM design. They question that visual cortical feature representations can be explained by a coverage-continuity-compromise.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
