Laboratory of Neurobiology, The Rockefeller University, New York, New York, United States of America.
PLoS Biol. 2010 Jun 15;8(6):e1000395. doi: 10.1371/journal.pbio.1000395.
Cortical topography can be remapped as a consequence of sensory deprivation, suggesting that cortical circuits are continually modified by experience. To see the effect of altered sensory experience on specific components of cortical circuits, we imaged neurons, labeled with a genetically modified adeno-associated virus, in the intact mouse somatosensory cortex before and after whisker plucking. Following whisker plucking we observed massive and rapid reorganization of the axons of both excitatory and inhibitory neurons, accompanied by a transient increase in bouton density. For horizontally projecting axons of excitatory neurons there was a net increase in axonal projections from the non-deprived whisker barrel columns into the deprived barrel columns. The axon collaterals of inhibitory neurons located in the deprived whisker barrel columns retracted in the vicinity of their somata and sprouted long-range projections beyond their normal reach towards the non-deprived whisker barrel columns. These results suggest that alterations in the balance of excitation and inhibition in deprived and non-deprived barrel columns underlie the topographic remapping associated with sensory deprivation.
皮层拓扑结构可以作为感觉剥夺的结果而被重新映射，这表明皮层回路不断地被经验所改变。为了观察改变的感觉经验对皮层回路特定成分的影响，我们在完整的小鼠体感皮层中对使用基因修饰的腺相关病毒标记的神经元进行成像，在剪去胡须之前和之后进行观察。在剪去胡须之后，我们观察到兴奋性和抑制性神经元的轴突发生了大规模和快速的重组，伴随着突触及密度的短暂增加。对于水平投射的兴奋性神经元的轴突，来自非剥夺的胡须桶柱的轴突投射到剥夺的胡须桶柱中有净增加。位于剥夺的胡须桶柱中的抑制性神经元的轴突侧支在它们的胞体附近回缩，并向非剥夺的胡须桶柱长出远距离的投射，超出了它们的正常范围。这些结果表明，在剥夺和非剥夺的桶柱中，兴奋和抑制的平衡的改变是与感觉剥夺相关的拓扑重映射的基础。
