葡萄牙尚帕利莫未知技术中心Megan R. Carey、Dominique L. Pritchett研究小组发现，攀缘纤维为联想学习提供了重要的指导性信号。相关论文于2024年4月2日发表于国际顶尖学术期刊《自然—神经科学》杂志上。

据了解，监督式学习依赖于指导性信号，这些信号塑造神经回路的输出，以支持习得的行为改变。攀缘纤维(CF)输入到小脑皮层是脊椎动物大脑中传递神经指导信号的最强候选之一。然而，最近的研究表明，浦肯野细胞刺激也可以驱动小脑学习，这两种神经元类型在为小脑依赖行为提供指向性信号方面的相对重要性仍未得到解决。

在本研究中，课题组研究人员对各种小脑回路元件的细胞类型进行特异性干扰，以系统地评估它们对小鼠延迟眨眼条件反射的贡献。研究结果表明，尽管光遗传刺激攀缘纤维或浦肯野细胞可以在某些条件下驱动学习，但即使攀缘纤维信号的细微减少也完全阻碍了自然刺激的学习。该研究得出结论，攀缘纤维和相应的浦肯野细胞复合体尖峰响应，为关联性小脑学习提供了重要的指导信号。

附：英文原文

Title: Climbing fibers provide essential instructive signals for associative learning

Author: Silva, N. Tatiana, Ramrez-Buritic, Jorge, Pritchett, Dominique L., Carey, Megan R.

Issue&Volume: 2024-04-02

Abstract: Supervised learning depends on instructive signals that shape the output of neural circuits to support learned changes in behavior. Climbing fiber (CF) inputs to the cerebellar cortex represent one of the strongest candidates in the vertebrate brain for conveying neural instructive signals. However, recent studies have shown that Purkinje cell stimulation can also drive cerebellar learning and the relative importance of these two neuron types in providing instructive signals for cerebellum-dependent behaviors remains unresolved. In the present study we used cell-type-specific perturbations of various cerebellar circuit elements to systematically evaluate their contributions to delay eyeblink conditioning in mice. Our findings reveal that, although optogenetic stimulation of either CFs or Purkinje cells can drive learning under some conditions, even subtle reductions in CF signaling completely block learning to natural stimuli. We conclude that CFs and corresponding Purkinje cell complex spike events provide essential instructive signals for associative cerebellar learning.

DOI: 10.1038/s41593-024-01594-7

Source: https://www.nature.com/articles/s41593-024-01594-7