Committee on Computational Neuroscience, University of Chicago, Chicago, IL, USA.
Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL, USA.
Cereb Cortex. 2019 Dec 17;29(11):4613-4627. doi: 10.1093/cercor/bhy337.
Manual interactions with objects require precise and rapid feedback about contact events. These tactile signals are integrated with motor plans throughout the neuraxis to achieve dexterous object manipulation. To better understand the role of somatosensory cortex in interactions with objects, we measured, using chronically implanted arrays of electrodes, the responses of populations of somatosensory neurons to skin indentations designed to simulate the initiation, maintenance, and termination of contact with an object. First, we find that the responses of somatosensory neurons to contact onset and offset dwarf their responses to maintenance of contact. Second, we show that these responses rapidly and reliably encode features of the simulated contact events-their timing, location, and strength-and can account for the animals' performance in an amplitude discrimination task. Third, we demonstrate that the spatiotemporal dynamics of the population response in cortex mirror those of the population response in the nerves. We conclude that the responses of populations of somatosensory neurons are well suited to encode contact transients and are consistent with a role of somatosensory cortex in signaling transitions between task subgoals.
与物体的手动交互需要有关接触事件的精确和快速反馈。这些触觉信号与整个神经系统中的运动计划相结合，以实现灵巧的物体操作。为了更好地了解感觉皮层在与物体交互中的作用，我们使用慢性植入的电极阵列测量了感觉神经元群体对皮肤凹陷的反应，这些凹陷旨在模拟与物体的接触开始、维持和终止。首先，我们发现感觉神经元对接触开始和结束的反应远小于它们对接触维持的反应。其次，我们表明，这些反应可以快速可靠地对模拟接触事件的特征进行编码——它们的时间、位置和强度，并可以解释动物在幅度辨别任务中的表现。第三，我们证明了皮层中群体反应的时空动态与神经中的群体反应相呼应。我们的结论是，感觉神经元群体的反应非常适合编码接触瞬变，并且与感觉皮层在信号任务子目标之间的转换中的作用一致。
