Modeling the natural variability in the shape of dendritic trees: Application to basal dendrites of small rat cortical layer 5 pyramidal neurons

The emergence of dendritic complexity is studied by means of a mathematical model, based on randomly branching and randomly propagating growth cones. Branching probabilities, which depend on the position and decrease with the number of growth cones in the growing tree, are su$cient to account for the observed variation in the number and connectivity pattern of dendritic segments. Segment length distributions of small rat cortical layer 5 pyramidal cell basal dendrites are now accurately reproduced by also assuming randomness in the rate of growth cone propagation. Di!erent mean propagation rates are predicted for two distinct phases of dendritic development. ( 1999 Elsevier Science B.V. All rights reserved.