Giovannucci Andrea, Badura Aleksandra, Deverett Ben, Najafi Farzaneh, Pereira Talmo D, Gao Zhenyu, Ozden Ilker, Kloth Alexander D, Pnevmatikakis Eftychios, Paninski Liam, De Zeeuw Chris I, Medina Javier F, Wang Samuel S-H
Princeton Neuroscience Institute and Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Center for Computational Biology, Flatiron Institute, Simons Foundation, New York, New York, USA.
Nat Neurosci. 2017 May;20(5):727-734. doi: 10.1038/nn.4531. Epub 2017 Mar 20.
Cerebellar granule cells, which constitute half the brain's neurons, supply Purkinje cells with contextual information necessary for motor learning, but how they encode this information is unknown. Here we show, using two-photon microscopy to track neural activity over multiple days of cerebellum-dependent eyeblink conditioning in mice, that granule cell populations acquire a dense representation of the anticipatory eyelid movement. Initially, granule cells responded to neutral visual and somatosensory stimuli as well as periorbital airpuffs used for training. As learning progressed, two-thirds of monitored granule cells acquired a conditional response whose timing matched or preceded the learned eyelid movements. Granule cell activity covaried trial by trial to form a redundant code. Many granule cells were also active during movements of nearby body structures. Thus, a predictive signal about the upcoming movement is widely available at the input stage of the cerebellar cortex, as required by forward models of cerebellar control.
小脑颗粒细胞构成了大脑神经元的一半，为浦肯野细胞提供运动学习所需的情境信息，但它们如何编码这些信息尚不清楚。在这里，我们使用双光子显微镜在小鼠依赖小脑的眨眼条件反射的多天时间里追踪神经活动，结果表明颗粒细胞群体获得了预期眼睑运动的密集表征。最初，颗粒细胞对中性视觉和体感刺激以及用于训练的眶周吹气有反应。随着学习的进展，三分之二被监测的颗粒细胞获得了一种条件反应，其时间与习得的眼睑运动相匹配或先于习得的眼睑运动。颗粒细胞活动逐次协变以形成冗余编码。许多颗粒细胞在附近身体结构的运动过程中也很活跃。因此，正如小脑控制的前馈模型所要求的那样，在小脑皮质的输入阶段广泛存在关于即将发生运动的预测信号。
