Wang Xiaolan, Fung C C Alan, Guan Shaobo, Wu Si, Goldberg Michael E, Zhang Mingsha
Department of Neuroscience, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA; Kavli Institute for Neuroscience, Columbia University, New York, NY 10032, USA.
State Key Laboratory of Cognitive Neuroscience and Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China; Department of Physics, The Hong Kong University of Science and Technology, Clear Water, Hong Kong, China.
Neuron. 2016 Apr 20;90(2):400-9. doi: 10.1016/j.neuron.2016.02.035. Epub 2016 Mar 31.
Humans and monkeys have access to an accurate representation of visual space despite a constantly moving eye. One mechanism by which the brain accomplishes this is by remapping visual receptive fields around the time of a saccade. In this process a neuron can be excited by a probe stimulus in the current receptive field, and also simultaneously by a probe stimulus in the location that will be brought into the neuron's receptive field by the saccade (the future receptive field), even before saccade begins. Here we show that perisaccadic neuronal excitability is not limited to the current and future receptive fields but encompasses the entire region of visual space across which the current receptive field will be swept by the saccade. A computational model shows that this receptive field expansion is consistent with the propagation of a wave of activity across the cerebral cortex as saccade planning and remapping proceed.
尽管眼睛在不断移动,但人类和猴子仍能获得视觉空间的精确表征。大脑实现这一点的一种机制是在扫视发生时重新映射视觉感受野。在这个过程中,一个神经元可以被当前感受野中的探测刺激所激发,同时也可以被扫视将带入该神经元感受野的位置(未来感受野)中的探测刺激所激发,甚至在扫视开始之前。在这里,我们表明扫视周围的神经元兴奋性不仅限于当前和未来的感受野,而是涵盖了当前感受野将被扫视扫过的整个视觉空间区域。一个计算模型表明,这种感受野扩展与扫视计划和重新映射过程中活动波在大脑皮层中的传播是一致的。