Dellen Babette K, Clark John W, Wessel Ralf
Bernstein Center for Computational Neuroscience Göttingen, Max-Planck-Institute for Dynamics and Self-Organization, Bunsenstrasse 10, 37073 Göttingen, Germany.
Spat Vis. 2009;22(4):301-24. doi: 10.1163/156856809788746291.
We propose a generalized energy model of complex cells to describe modulatory contextual influences on the responses of neurons in the primary visual cortex (V1). Many orientation-selective cells in V1 respond to contrast of orientation and motion of stimuli exciting the classical receptive field (CRF) and the non-CRF, or surround. In the proposed model, a central spatiotemporal filter, defining the CRF, is nonlinearly combined with a spatiotemporal filter extending into the non-CRF. These filters are assumed to describe simple-cell responses, while the nonlinear combination of their responses describes the responses of complex cells. This mathematical operation accounts for the inherent nonlinearity of complex cells, such as phase independence and frequency doubling, and for nonlinear interactions between stimuli in the CRF and surround of the cell, including sensitivity to feature contrast. If only the CRF of the generalized complex cell is stimulated by a drifting grating, the model reduces to the standard energy model. The theoretical predictions of the model are supported by computer simulations and compared with experimental data from V1.
我们提出了一种复杂细胞的广义能量模型，以描述对初级视觉皮层（V1）中神经元反应的调制性上下文影响。V1中的许多方向选择性细胞对刺激经典感受野（CRF）和非CRF（即周围区域）的方向对比度和运动做出反应。在所提出的模型中，定义CRF的中央时空滤波器与延伸到非CRF的时空滤波器进行非线性组合。这些滤波器被假定用于描述简单细胞的反应，而它们反应的非线性组合则描述复杂细胞的反应。这种数学运算解释了复杂细胞固有的非线性，如相位独立性和频率加倍，以及细胞CRF和周围区域中刺激之间的非线性相互作用，包括对特征对比度的敏感性。如果仅由漂移光栅刺激广义复杂细胞的CRF，该模型就简化为标准能量模型。该模型的理论预测得到了计算机模拟的支持，并与来自V1的实验数据进行了比较。
