Rasmussen C E, Willshaw D J
Centre for Cognitive Science, University of Edinburgh, Scotland, United Kingdom.
Biol Cybern. 1993;68(5):409-19. doi: 10.1007/BF00198773.
In the establishment of connections between nerve and muscle there is an initial stage when each muscle fibre is innervated by several different motor axons. Withdrawal of connections then takes place until each fibre has contact from just a single axon. The evidence suggests that the withdrawal process involves competition between nerve terminals. We examine in formal models several types of competitive mechanism that have been proposed for this phenomenon. We show that a model which combines competition for a presynaptic resource with competition for a postsynaptic resource is superior to others. This model accounts for many anatomical and physiological findings and has a biologically plausible implementation. Intrinsic withdrawal appears to be a side effect of the competitive mechanism rather than a separate non-competitive feature. The model's capabilities are confirmed by theoretical analysis and full scale computer simulations.
在神经与肌肉建立连接的过程中，存在一个初始阶段，此时每条肌纤维由几种不同的运动轴突支配。随后连接会逐渐减少，直到每条纤维仅与单个轴突建立联系。有证据表明，减少过程涉及神经末梢之间的竞争。我们在形式模型中研究了针对这一现象提出的几种竞争机制。我们表明，一种将对突触前资源的竞争与对突触后资源的竞争相结合的模型优于其他模型。该模型解释了许多解剖学和生理学发现，并且具有生物学上合理的实现方式。内在减少似乎是竞争机制的副作用，而非一个独立的非竞争特征。该模型的能力通过理论分析和全面的计算机模拟得到了证实。
