CEREBRAL CORTICAL MECHANISMS FOR EYE MOVEMENTS AND VISUAL ATTENTION

研究人员通过三条线索来确定大脑皮层如何 它的传出区域控制眼球运动和视觉空间注意力。 在第一首单曲中，用神经元记录来探索这种机制 借此，猴子的顶叶皮质达到了空间上的准确性。它是 众所周知，顶神经元对某个部位的刺激有反应。 视网膜，也就是接受野。顶叶神经元的感受野 在眼球跳动前的瞬间变化，这样他们就会做出反应， 在眼球运动之前，刺激将在他们的接受区 在运动之后。与此同时，目前的视网膜位置变成了 没有反应。这些数据证实了视网膜有一种特定的移位 感受野，而不是兴奋性的一般变化。 在第二项研究中，我们评估了恒河猴的眼球运动能力。 当猴子在实验前后执行眼球运动任务时 小脑深部核团的电解性损害。我们的一些赤字 发现这与小脑发挥调节作用是一致的 眼球跳动的幅度，但不是在启动它们时：猴子 他们眼球跳动的幅度变化性增加， 他们倾向于超过目标，这种不准确是依赖于 根据眼睛在轨道上的初始位置；他们无法调整 针对目标运动的眼跳运动的幅度；以及他们 无法在模型中调整他们眼球跳动的幅度 肌肉无力的症状。 第三，人类小脑上端蒂的表现 损伤是在平稳追踪任务中研究的。相互之间的交叉耦合 演示了扭转和垂直追逐系统。

Three lines of inquiry were followed to determine how the cerebral cortex and its efferent regions control eye movements and visuospatial attention. In the first single, a neuron recording was used to probe the mechanisms whereby the parietal cortex of the monkey achieves spatial accuracy. It is well known that parietal neurons respond to stimuli in a certain location o the retina, the receptive field. The receptive fields of parietal neurons transiently change before a saccadic eye movement, so that they respond, before the eye movement, to stimuli that will be in their receptive fields after the movement. At the same time, the current retinal location becomes unresponsive. These data establish that there is a specific shift of retina receptive field, rather than a general change of excitability. In the second, the oculomotor performance of rhesus monkeys was assessed while the monkeys performed an oculomotor task before and after electrolytic lesions of the deep cerebellar nuclei. A number of deficits we found that were consistent with the cerebellum playing a role in adjusting the amplitude of saccadic eye movements but not in initiating them: monkeys had increased variability in the amplitude of their saccadic eye movements, they had tended to overshoot targets and this inaccuracy was dependent upon the initial position of the eye in the orbit; they were unable to adju the amplitude of their saccadic eye movements for target motion; and they could not adjust the amplitude of their saccadic eye movements in a model of muscle weakness. In the third, the performance of humans with superior cerebellar peduncle lesions was studied in a smooth pursuit task. Cross-coupling between the torsional and vertical pursuit systems was demonstrated.