Pouget A, Sejnowski T J
Department of Brain and Cognitive Sciences, University of Rochester, New York 14627, USA.
Psychol Rev. 2001 Jul;108(3):653-73. doi: 10.1037/0033-295x.108.3.653.
The basis function theory of spatial representations explains how neurons in the parietal cortex can perform nonlinear transformations from sensory to motor coordinates. The authors present computer simulations showing that unilateral parietal lesions leading to a neuronal gradient in basis function maps can account for the behavior of patients with hemineglect, including (a) neglect in line cancellation and line bisection experiments; (b) neglect in multiple frames of reference simultaneously; (c) relative neglect, a form of what is sometime called object-centered neglect; and (d) neglect without optic ataxia. Contralateral neglect arises in the model because the lesion produces an imbalance in the salience of stimuli that is modulated by the orientation of the body in space. These results strongly support the basis function theory for spatial representations in humans and provide a computational model of hemineglect at the single-cell level.
空间表征的基函数理论解释了顶叶皮质中的神经元如何执行从感觉坐标到运动坐标的非线性转换。作者进行了计算机模拟，结果表明，导致基函数图中神经元梯度的单侧顶叶损伤可以解释半侧空间忽视患者的行为，包括：（a）在线条消除和线条二等分实验中的忽视；（b）同时在多个参照系中的忽视；（c）相对忽视，一种有时被称为以物体为中心的忽视形式；以及（d）无视觉性共济失调的忽视。在该模型中，对侧忽视的出现是因为损伤导致了由身体在空间中的方向所调节的刺激显著性失衡。这些结果有力地支持了人类空间表征的基函数理论，并提供了一个单细胞水平的半侧空间忽视计算模型。
