NEURONAL GROWTH VIA HYBRID SYSTEM OF SELF-GROWING AND DIFFUSION-BASEDGRAMMAR RULES .1.

The formation of neuronal networks requires axonal growth towards targ et neurons. A simple set of grammar rules is introduced to describe ax onal growth towards target cells situated both at short and long dista nces from the growing neuron. Growth for short distances is described by growth following the highest gradient of a chemical compound (which is spread by diffusion from the targets). This approach fails to desc ribe long-distance growth, which is addressed by adopting a graph gram mar theory for growing toes. With these rules a flexible tool to draw network of neurons by computer can be developed.