The goal of this short review is to call attention to a yawning gap of knowledge that separates two processes essential for saccade production. On the one hand, knowledge about the saccade generation circuitry within the brainstem is detailed and precise – push-pull interactions between gaze-shifting and gaze-holding processes control the time of saccade initiation, which begins when omnipause neurons are inhibited and brainstem burst neurons are excited. On the other hand, knowledge about the cortical and subcortical premotor circuitry accomplishing saccade initiation has crystalized around the concept of stochastic accumulation – the accumulating activity of saccade neurons reaching a fixed value triggers a saccade. Here is the gap: we do not know how the reaching of a threshold by premotor neurons causes the critical pause and burst of brainstem neurons that initiates saccades. Why this problem matters and how it can be addressed will be discussed. Closing the gap would unify two rich but curiously disconnected empirical and theoretical domains.

这篇简短评论的目的是引起人们对一个巨大的知识差距的关注，该差距将两个对眼跳产生至关重要的过程分开。一方面，关于脑干内扫视生成电路的知识是详细而精确的——凝视转移和凝视保持过程之间的推拉交互控制了扫视开始的时间，当全脑神经元被抑制和脑干神经元爆裂时开始很兴奋。另一方面，关于完成跳视启动的皮层和皮层下运动前回路的知识已经围绕随机积累的概念具体化——跳视神经元的累积活动达到固定值会触发跳视。这是差距：我们不知道运动前神经元达到阈值是如何导致引发跳视的脑干神经元的关键停顿和爆发。将讨论为什么这个问题很重要以及如何解决它。缩小差距将统一两个丰富但奇怪地相互关联的经验和理论领域。