Suvrathan Aparna, Payne Hannah L, Raymond Jennifer L
Department of Neurobiology, Stanford University, Stanford, CA 94305, USA.
Department of Neurobiology, Stanford University, Stanford, CA 94305, USA.
Neuron. 2016 Dec 7;92(5):959-967. doi: 10.1016/j.neuron.2016.10.022. Epub 2016 Nov 10.
It is widely assumed that the complexity of neural circuits enables them to implement diverse learning tasks using just a few generic forms of synaptic plasticity. In contrast, we report that synaptic plasticity can itself be precisely tuned to the requirements of a learning task. We found that the rules for induction of long-term and single-trial plasticity at parallel fiber-to-Purkinje cell synapses vary across cerebellar regions. In the flocculus, associative plasticity in vitro and in vivo is narrowly tuned for an interval of ∼120 ms, which compensates for the specific processing delay for error signals to reach the flocculus during oculomotor learning. In the vermis, which supports a range of behavioral functions, plasticity is induced by a range of intervals, with individual cells tuned for different intervals. Thus, plasticity at a single, anatomically defined type of synapse can have properties that vary in a way that is precisely matched to function.
人们普遍认为，神经回路的复杂性使它们能够仅通过几种通用形式的突触可塑性来执行各种学习任务。相比之下，我们报告称，突触可塑性本身可以根据学习任务的要求进行精确调整。我们发现，平行纤维到浦肯野细胞突触处长期和单次试验可塑性的诱导规则在小脑区域有所不同。在绒球中，体外和体内的联合可塑性在约120毫秒的时间间隔内被精确调整，这补偿了眼动学习期间误差信号到达绒球的特定处理延迟。在支持一系列行为功能的蚓部，可塑性由一系列时间间隔诱导，单个细胞针对不同的时间间隔进行调整。因此，在单一解剖学定义的突触类型处的可塑性可以具有以与功能精确匹配的方式变化的特性。
