PMC

Neuronal number control in the developing nervous system. In the developing PNS, neurons compete for survival factors, such as neurotrophins, provided by targeted cells as a means of attaining optimal innervation. In the developing CNS, there are two proposed models for interneuron cell death. (1) ‘Individual autonomous’ model: interneuron cell death is intrinsically determined within each interneuron precursor in a manner independent from their interactions with other cells; each cell has a probability of Pi to survive; (2) ‘Population autonomous’ model: developing interneurons compete for limited survival signals produced by other interneurons born around the same time; individual neurons affect each other and the population as a whole has a probability of Pi to survive.