Activity of neurons in area 6 of the cat during fixation and eye movements.
Activity of neurons in area 6 of the cat during fixation and eye movements.
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猫注视和眼球运动期间第 6 区神经元的活动。
DOI：
10.1017/s0952523898151088
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发表时间：
1998
影响因子：
1.9
通讯作者：
Gafka,AC
中科院分区：
文献类型：
--
作者：
Weyand,TG;Gafka,AC
我们研究了6区的645个神经元的视觉特性，在5只猫接受训练，在视觉任务。我们记录的区域与据信包含在灵长类动物中观察到的前眼区的猫科同源物的区域相对应。尽管预期具有扫视前活动的细胞将是常见的，但只有一小部分（约5%）的细胞显示出可能与随后的扫视眼球运动有关的活动。这些前运动细胞似乎分布在皮层的一个广泛区域，与其他细胞类型混合在一起。在灵长类动物中，与扫视相关的活动往往只发生在“有目的的”扫视期间。至少30%（208/645）的神经元是视觉神经元，其中许多细胞拥有巨大的感受野，似乎包括整个对侧视野。视觉反应一般衰减固定在眼科任务。虽然注意力机制可能在这种衰减中发挥作用，但该皮层区域也表现出强大的横向相互作用，其中空间移位的视觉刺激相互抑制。大多数细胞，视觉反应或没有，固定的影响。几乎相同比例的细胞在固定过程中表现出活性的增加或减少。对于许多受固定影响的细胞来说，这种调节的来源似乎反映了认知过程，而不是感觉或运动过程。这包括表现出预期活动的细胞，以及只有在任务背景下才会对奖励做出反应的细胞。基于扫视前神经元的缺乏，很难得出结论，猫的这一皮层区域与猴子的额叶眼区是同源的。然而，当考虑到这两种动物的眼部习惯的差异时，我们相信同源性符合。除了前运动神经元，在这个区域发现的其他几种细胞类型的特性可能有助于控制凝视。
We studied the visuomotor properties of 645 neurons in area 6 of five cats trained in oculomotor tasks. The area we recorded from corresponds well with territories believed to contain the feline homologue of the frontal eye fields observed in primates. Despite an expectation that cells with pre-saccadic activity would be common, only a small fraction (∼5%) of the cells displayed activity that could be linked to subsequent saccadic eye movements. These pre-motor cells appeared to be distributed over a broad region of cortex mixed in with other cell types. As in primates, saccade-related activity tended to occur only during “purposeful” saccades. At least 30% (208/645) of the neurons were visual, with many of these cells possessing huge receptive fields that appeared to include the entire contralateral visual field. Visual responsiveness was generally attenuated by fixation during the oculomotor tasks. Although attentional mechanisms may play a role in this attenuation, this cortical area also exhibits powerful lateral interactions in which spatially displaced visual stimuli suppress each other. Most cells, visually responsive or not, were affected by fixation. Nearly equal proportions of cells showed increases or decreases in activity during fixation. For many of the cells affected by fixation, the source of this modulation appears to reflect cognitive, rather than sensory or motor processes. This included cells that showed anticipatory activity, and cells that responded to the reward only when it was presented in the context of the task. Based on the paucity of pre-saccadic neurons, it would be difficult to conclude that this region of cortex in the cat is homologous to the frontal eye fields of the monkey. However, when considered in the context of differences in the oculomotor habits of these two animals, we believe the homology fits. In addition to pre-motor neurons, the properties of several other cell types found in this area could contribute to the control of gaze.