Selective activation of visual cortex neurons by fixational eye movements: Implications for neural coding
Selective activation of visual cortex neurons by fixational eye movements: Implications for neural coding
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DOI：
10.1017/s0952523801182118
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发表时间：
2001-03-01
影响因子：
1.9
通讯作者：
Gur, M
中科院分区：
文献类型：
--
作者：
Snodderly, DM;Kagan, I;Gur, M
在正常视觉期间，当受试者试图将他们的注视固定在小刺激特征上时，小的注视眼球运动持续存在。我们记录了猕猴初级视皮层（V1）单个神经元的脉冲活动，而他们的注视眼运动移动的感受野激活区（AR）的上方和周围的一个固定的刺激。研究发现，眼动激活有三种类型：（1）当注视：II眼跳将AR移到刺激物上、离开刺激物或穿过刺激物时，眼跳细胞放电。(2)位置/漂移呼叫在扫视间（漂移）间隔期间放电，并且不被扫视激活，扫视使AR扫过刺激而不停留在它上面。为了激活这些神经元，AR被放置在刺激上是至关重要的，并且这些细胞中的许多细胞对对比度的符号是有选择性的。它们的AR比其他细胞类型更小。(3)混合细胞在扫视后立即爆发活动，并在扫视间隔期间继续以较低的速率发射。每个神经元的倾向，消防短暂的突发或持续列车的冲动后眼跳是强烈相关的，其响应的短暂性，以固定的闪光刺激。对于一只猴子，确定了伴随注视扫视的视网膜外影响。在自然观看过程中，不同的眼动类别可能对视觉加工做出不同的贡献。位置/漂移神经元非常适合于编码视觉场景的空间细节，因为它们的小AR尺寸和它们对对比度和视网膜位置的选择性。然而，扫视神经元传输相对于视网膜图像的空间细节模糊的信息，因为无论AR落在刺激轮廓上，还是AR离开或穿过轮廓并落在另一个位置，它们都被激活。扫视神经元可能参与构建一个稳定的世界，尽管不断的视网膜图像运动，以及在抑制潜在的混乱输入与扫视。
During normal vision, when subjects attempt to fix their gaze on a small stimulus feature, small fixational eye movements persist. We have recorded the impulse activity of single neurons in primary visual cortex (V1) of macaque monkeys while their fixational eye movements moved the receptive-field activating region (AR) over and around a stationary stimulus. Three types of eye movement activation were found. (1) Saccade cells discharged when a Fixation:ll saccade moved the AR onto the stimulus, off the stimulus, or across the stimulus. (2) Position/drift calls discharged during the intersaccadic (drift) intervals and were not activated by saccades that swept the AR across the stimulus without remaining on it. To activate these neurons, it was essential that the AR be placed on the stimulus and many of these cells were selective for the sign of contrast. They had smaller ARs than the other cell types. (3) Mixed cells fired bursts of activity immediately following saccades and continued to fire at a lower rate during intersaccadic intervals. The tendency of each neuron to fire transient bursts or sustained trains of impulses following saccades was strongly correlated with the transiency of its response to stationary flashed stimuli. For one monkey, an extraretinal influence accompanying fixational saccades was identified. During natural viewing, the different eye movement classes probably make different contributions to visual processing. Position/drift neurons are well suited for coding spatial details of the visual scene because of their small AR size and their selectivity for sign of contrast and retinal position. However, saccade neurons transmit information that is ambiguous with respect to the spatial details of the retinal image because they are activated whether the AR lands on a stimulus contour, or the AR leaves or crosses the contour and lands in another location. Saccade neurons may be involved in constructing a stable world in spite of incessant retinal image motion, as well as in suppressing potentially confusing input associated with saccades.