Department of Cellular and Physiological Sciences and the Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.
PLoS Biol. 2012 Jan;10(1):e1001236. doi: 10.1371/journal.pbio.1001236. Epub 2012 Jan 10.
Sensory experience drives dramatic structural and functional plasticity in developing neurons. However, for single-neuron plasticity to optimally improve whole-network encoding of sensory information, changes must be coordinated between neurons to ensure a full range of stimuli is efficiently represented. Using two-photon calcium imaging to monitor evoked activity in over 100 neurons simultaneously, we investigate network-level changes in the developing Xenopus laevis tectum during visual training with motion stimuli. Training causes stimulus-specific changes in neuronal responses and interactions, resulting in improved population encoding. This plasticity is spatially structured, increasing tuning curve similarity and interactions among nearby neurons, and decreasing interactions among distant neurons. Training does not improve encoding by single clusters of similarly responding neurons, but improves encoding across clusters, indicating coordinated plasticity across the network. NMDA receptor blockade prevents coordinated plasticity, reduces clustering, and abolishes whole-network encoding improvement. We conclude that NMDA receptors support experience-dependent network self-organization, allowing efficient population coding of a diverse range of stimuli.
感觉体验驱动发育神经元产生显著的结构和功能可塑性。然而，为了使单个神经元的可塑性能够最佳地改善感觉信息的整个网络编码，必须协调神经元之间的变化，以确保有效地表示整个刺激范围。我们使用双光子钙成像来监测超过 100 个神经元在使用运动刺激进行视觉训练期间的诱发活动，研究了发育中的非洲爪蟾视顶盖在视觉训练期间的网络级变化。训练导致神经元反应和相互作用的刺激特异性变化，从而提高了群体编码。这种可塑性具有空间结构，增加了调谐曲线相似性和附近神经元之间的相互作用，减少了远距离神经元之间的相互作用。训练不能通过类似反应的神经元的单个簇来改善编码，而是改善跨簇的编码，表明网络中的协调性可塑性。NMDA 受体阻断可防止协调性可塑性，减少聚类并消除整个网络编码的改善。我们得出结论，NMDA 受体支持经验依赖性网络自组织，允许对各种刺激进行有效的群体编码。
