Functional microarchitecture underlying target selection and saccade generation in the primate frontal eye field

无论我们是在人群中寻找朋友，还是试图在凌乱的桌子上找到一支笔，我们的大脑都必须不断区分许多不同的视觉对象。为了详细地检查视觉对象，我们通常会看着它，以便对象福尔斯在我们视网膜上分辨率最高的区域。然而，正如我们从日常经验中所知道的那样，我们也可以在保持眼睛静止的同时将注意力转移到视野的外围。这种形式的注意力被认为是一种神经过程，它增强了来自视野特定部分的信号。目前的观点是，控制眼球运动的大脑区域也会进行注意力转移。根据这一假设，注意力转移被认为是有计划的眼球运动。这一观点得到了人类脑功能成像研究的支持。这些研究表明，大脑前部的一个大脑区域，称为额叶眼区，对眼球运动和注意力转移都很活跃。然而，对猴子的研究记录了额叶眼区单个神经细胞的活动，表明不同的神经细胞群可能参与眼球运动和注意力转移。为了直接测试额叶眼野神经细胞是否向脑干中控制眼球运动的神经机制和大脑后部与视觉有关的大脑区域发送相同类型的信号，我们将在猴子身上识别并记录这些信号。这些实验将直接测试注意力的转移是否涉及额叶眼区的神经细胞群，这些神经细胞群也控制眼球运动。

Whether we look for a friend in the crowd or try to find a pen on our messy desk, our brain has to constantly distinguish between many different visual objects. To examine a visual object in detail, we generally look towards it so that the object falls on the region of our retina that has the highest resolution. However, as we all know from daily experience, we can also shift our attention to the periphery of our visual field while keeping our eyes still. This form of attention is thought to be a neural process that enhances the signals from a particular part of the visual field. The current view is that the brain areas that control eye movements also perform shifts of attention. According to this hypothesis, shifts of attention are thought to be planned eye movements. This view has been supported by functional brain imaging studies in humans. These studies have shown that a brain area in the frontal part of the brain, called the frontal eye field, is active both for eye movements and shifts of attention. However, studies in monkeys that recorded the activity of single nerve cells in the frontal eye field have suggested that separate groups of nerve cells may be involved in eye movements and shifts of attention. To directly test whether frontal eye field nerve cells send the same type of signal to the neural machinery in the brain stem that controls eye movements and to brain areas in the back of the brain that are involved in vision, we will identify and record these signals in monkeys. These experiments will directly test whether shifts of attention involve the groups of nerve cells in the frontal eye field that also control eye movements.