College of Engineering, Computing and Mathematics, University of Exeter, North Park Road, Exeter, EX4 4QF, UK.
Biol Cybern. 2020 Oct;114(4-5):519-532. doi: 10.1007/s00422-020-00845-7. Epub 2020 Sep 30.
The rapid eye movements (saccades) used to transfer gaze between targets are examples of an action. The behaviour of saccades matches that of the slow-fast model of actions originally proposed by Zeeman. Here, we extend Zeeman's model by incorporating an accumulator that represents the increase in certainty of the presence of a target, together with an integrator that converts a velocity command to a position command. The saccadic behaviour of several foveate species, including human, rhesus monkey and mouse, is replicated by the augmented model. Predictions of the linear stability of the saccadic system close to equilibrium are made, and it is shown that these could be tested by applying state-space reconstruction techniques to neurophysiological recordings. Moreover, each model equation describes behaviour that can be matched to specific classes of neurons found throughout the oculomotor system, and the implication of the model is that build-up, burst and omnipause neurons are found throughout the oculomotor pathway because they constitute the simplest circuit that can produce the motor commands required to specify the trajectories of motor actions.
快速眼动（扫视）用于在目标之间转移注视，是动作的一个例子。扫视的行为与 Zeeman 最初提出的动作慢-快模型相匹配。在这里，我们通过引入一个累加器来扩展 Zeeman 的模型，该累加器代表目标存在的确定性的增加，同时引入一个积分器，将速度命令转换为位置命令。包括人类、恒河猴和老鼠在内的几种有中心凹的物种的扫视行为都可以通过增强模型来复制。对扫视系统在接近平衡时的线性稳定性进行了预测，并表明可以通过将状态空间重建技术应用于神经生理学记录来测试这些预测。此外，每个模型方程都描述了可以与整个眼动系统中发现的特定神经元类相匹配的行为，并且该模型的含义是，构建、爆发和全暂停神经元存在于整个眼动通路中，因为它们构成了可以产生指定运动动作轨迹所需的运动命令的最简单电路。
