Nordeen K W, Nordeen E J
Department of Brain and Cognitive Sciences, University of Rochester, New York 14627, USA.
J Neurobiol. 1997 Nov;33(5):532-48. doi: 10.1002/(sici)1097-4695(19971105)33:5<532::aid-neu4>3.0.co;2-5.
In songbirds, vocal learning occurs during periods of major cellular and synaptic change. This neural reorganization includes massive synaptogenesis associated with the addition of new neurons into the vocal motor pathway, as well as pruning of connections between song regions. These observations, coupled with behavioral evidence that song development requires NMDA receptor activation in specific song nuclei, suggest that experiences associated with vocal learning are encoded by activity driven, Hebbianlike processes of synaptic change akin to those implicated in many other forms of developmental plasticity and learning. In this review we discuss the hypothesis that develpmental and/or seasonal changes in NMDA receptor function and the availability of new synapses may modulate thresholds for plasticity and thereby define sensitive periods for vocal learning.
在鸣禽中，发声学习发生在主要的细胞和突触变化时期。这种神经重组包括与新神经元添加到发声运动通路相关的大量突触形成，以及鸣唱区域之间连接的修剪。这些观察结果，再加上行为证据表明鸣唱发育需要特定鸣唱核中的NMDA受体激活，表明与发声学习相关的经历是由活动驱动的、类似于赫布式的突触变化过程编码的，类似于许多其他形式的发育可塑性和学习中涉及的过程。在这篇综述中，我们讨论了这样一种假说，即NMDA受体功能的发育和/或季节性变化以及新突触的可用性可能调节可塑性阈值，从而确定发声学习的敏感期。
