The sudden appearance of a visual distractor shortly before saccade initiation can capture spatial attention and modulate the saccade trajectory in spite of the ongoing execution of the initial plan to shift gaze straight to the saccade target. To elucidate the neural correlates underlying these curved saccades, we recorded from single neurons in the frontal eye field of two male rhesus monkeys shifting gaze to a target while a distractor with the same eccentricity appeared either left or right of the target at various delays after target presentation. We found that the population level of presaccadic activity of neurons representing the distractor location encoded the direction of the saccade trajectory. Stronger activity occurred when saccades curved toward the distractor, and weaker when saccades curved away. This relationship held whether the distractor was ipsilateral or contralateral to the recorded neurons. Meanwhile, visually responsive neurons showed asymmetrical patterns of excitatory responses that varied with the location of the distractor and the duration of distractor processing relating to attentional capture and distractor inhibition. During earlier distractor processing, neurons encoded curvature toward the distractor. During later distractor processing, neurons encoded curvature away from the distractor. This was observed when saccades curved away from distractors contralateral to the recording site and when saccades curved toward distractors ipsilateral to the recording site. These findings indicate that saccadic motor planning involves dynamic push–pull hemispheric interactions producing attraction or repulsion for potential but unselected saccade targets.

尽管正在执行将视线直接转移到扫视目标的初始计划，但在扫视开始前不久突然出现的视觉干扰物可以捕获空间注意力并调节扫视轨迹。为了阐明这些弯曲扫视背后的神经相关性，我们从两只雄性恒河猴额眼场中的单个神经元中记录了将视线转移到目标上，而具有相同偏心率的干扰物在目标出现后以不同的延迟出现在目标的左侧或右侧。我们发现代表干扰物位置的神经元的扫视前活动总体水平编码了扫视轨迹的方向。当眼跳向干扰物弯曲时，活动更强，而当眼跳弯曲离开时，活动较弱。无论干扰物是记录的神经元的同侧还是对侧，这种关系都成立。同时，视觉反应神经元表现出不对称的兴奋反应模式，这些模式随干扰物的位置以及与注意力捕获和干扰物抑制相关的干扰物处理的持续时间而变化。在早期的干扰物处理过程中，神经元编码朝向干扰物的曲率。在后来的干扰物处理过程中，神经元对远离干扰物的曲率进行编码。当眼跳弯曲远离记录位点对侧的干扰物时，以及当扫视弯曲向记录位点同侧的干扰物时，可以观察到这种情况。这些发现表明，扫视运动计划涉及动态推拉半球相互作用，对潜在但未选择的扫视目标产生吸引力或排斥力。