Physiology of Active Vision Laboratory, Werner Reichardt Centre for Integrative Neuroscience, Tübingen University, Tübingen 72076, Germany.
Hertie Institute for Clinical Brain Research, Tübingen University, Tübingen 72076, Germany.
Proc Natl Acad Sci U S A. 2023 Sep 19;120(38):e2305759120. doi: 10.1073/pnas.2305759120. Epub 2023 Sep 11.
Movement control is critical for successful interaction with our environment. However, movement does not occur in complete isolation of sensation, and this is particularly true of eye movements. Here, we show that the neuronal eye movement commands emitted by the superior colliculus (SC), a structure classically associated with oculomotor control, encompass a robust visual sensory representation of eye movement targets. Thus, similar saccades toward different images are associated with different saccade-related "motor" bursts. Such sensory tuning in SC saccade motor commands appeared for all image manipulations that we tested, from simple visual features to real-life object images, and it was also strongest in the most motor neurons in the deeper collicular layers. Visual-feature discrimination performance in the motor commands was also stronger than in visual responses. Comparing SC motor command feature discrimination performance to that in the primary visual cortex during steady-state gaze fixation revealed that collicular motor bursts possess a reliable perisaccadic sensory representation of the peripheral saccade target's visual appearance, exactly when retinal input is expected to be most uncertain. Our results demonstrate that SC neuronal movement commands likely serve a fundamentally sensory function.
运动控制对于与我们的环境成功互动至关重要。然而，运动并不是完全与感觉隔离开来的，这在眼球运动中尤其如此。在这里，我们展示了上丘（SC）发出的神经元眼球运动指令，该结构通常与眼球运动控制有关，包含了对眼球运动目标的强大视觉感觉代表。因此，类似的扫视对不同的图像会产生不同的扫视相关“运动”爆发。这种在 SC 扫视运动指令中的感觉调谐似乎适用于我们测试的所有图像操作，从简单的视觉特征到现实生活中的物体图像，而且在较深的脑丘层中的大多数运动神经元中最强。运动指令中的视觉特征辨别性能也强于视觉反应。将 SC 运动命令特征辨别性能与在稳定注视时的初级视觉皮层进行比较，揭示了脑丘运动爆发在外周扫视目标的视觉外观上具有可靠的眼跳前感觉代表，而正是在视网膜输入最不确定的时候。我们的结果表明，SC 神经元运动指令可能具有基本的感觉功能。
