A sensory-motor decoder that transforms neural responses in extrastriate area MT into smooth pursuit eye movements.
A sensory-motor decoder that transforms neural responses in extrastriate area MT into smooth pursuit eye movements.
复制标题
一种感觉运动解码器，可将纹外区域 MT 的神经反应转化为平滑的眼球追踪运动。
DOI：
10.1101/2023.05.12.540526
复制
发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Lisberger,StephenG
中科院分区：
文献类型：
--
作者：
Behling,Stuart;Lisberger,StephenG
视觉运动通过感觉运动解码器驱动平滑的追踪眼球运动，该解码器使用多个并行神经通路将纹外区MT中的群体反应转化为运动。我们评估了解码器的挑战追求猴子减少运动的可靠性，通过减少运动的连贯性补丁的点。我们的策略是确定如何减少点的一致性改变人口的反应在MT。然后，我们预测的解码器，将MT人口的响应点相干诱导的赤字开始追求和稳态跟踪的属性。在追求启动，减少点相干性降低MT人口的响应幅度，而不改变其峰值的首选速度。成功的解码器通过将1）来自群体响应的峰值的目标速度的估计与2）基于群体响应的幅度的视觉运动增益相乘来再现所测量的眼球运动。在稳态跟踪过程中，用于追踪启动的解码器未能再现这样的悖论：尽管图像持续运动，但稳态眼速不会加速到目标速度。即使猴子的眼速稳定在远低于目标速度，它也能预测眼睛加速到目标速度。为了解释点相干性对稳态眼速的影响，我们假设解码器使用感觉运动增益来调制通常维持完美稳态跟踪的眼速正反馈。然后，由于低正反馈增益和MT驱动的加速度引起的眼减速之间的平衡，稳态跟踪持续不佳。NEW & NOTEWORTHY通过用降级的感觉刺激挑战感觉运动系统，我们揭示了感觉运动解码器如何将纹外区MT中的群体响应转换为平滑追踪眼运动的启动和稳态行为的命令。结论是基于测量MT中的多个目标速度和不同水平的运动可靠性的群体响应，并评估具有生物激励架构的解码器，以确定创建测量的眼球运动的解码器属性。
Visual motion drives smooth pursuit eye movements through a sensory-motor decoder that uses multiple parallel neural pathways to transform the population response in extrastriate area MT into movement. We evaluated the decoder by challenging pursuit in monkeys with reduced motion reliability created by reducing coherence of motion in patches of dots. Our strategy was to determine how reduced dot coherence changes the population response in MT. We then predicted the properties of a decoder that transforms the MT population response into dot coherence-induced deficits in the initiation of pursuit and steady-state tracking. During pursuit initiation, decreased dot coherence reduces MT population response amplitude without changing the preferred speed at its peak. The successful decoder reproduces the measured eye movements by multiplication of1) the estimate of target speed from the peak of the population response with2) visual-motor gain based on the amplitude of the population response. During steady-state tracking, the decoder that worked for pursuit initiation failed to reproduce the paradox that steady-state eye speeds do not accelerate to the target speed despite persistent image motion. It predicted eye acceleration to target speed even when monkeys’ eye speeds were steady at well below the target speed. To account for the effect of dot coherence on steady-state eye speed, we postulate that the decoder uses sensory-motor gain to modulate the eye velocity positive feedback that normally sustains perfect steady-state tracking. Then, poor steady-state tracking persists because of balance between eye deceleration caused by low positive feedback gain and acceleration driven by MT.NEW & NOTEWORTHYBy challenging a sensory-motor system with degraded sensory stimuli, we reveal how the sensory-motor decoder transforms the population response in extrastriate area MT into commands for the initiation and steady-state behavior of smooth pursuit eye movements. Conclusions are based on measuring population responses in MT for multiple target speeds and different levels of motion reliability and evaluating a decoder with a biologically motivated architecture to determine the decoder properties that create the measured eye movements.