The neural system is a complex self-wiring system, which consists of a huge number of interconnected individual cells (neurons). Two main types of signaling exist in a neural system: short-range synaptic signaling between neurons, provided by neurotransmitters, which acts on postsynaptic neuron's state and long(short)-range signaling by chemicals that acts on neuron's geometrical properties (position of cell, dendrites, axons). Each function of the mature neural system depends on the actions of distinct neuronal circuits and therefore proper functioning of the neural net depends on correctness of axonal projections and interneuronal connections. It is currently accepted that cortical maps are dynamic constructs that are remodeled in response to external input. Two types of plasticity in neural system are known: synaptic plasticity and structural plasticity. Synaptic plasticity involves activity-dependent weight changes between previously connected neurons. Structural plasticity includes remodeling of axons and dendrites, synapse formation and elimination. Dynamical rewiring could provide an important mechanism for information storage, although at a cost of more complex biological machinery and slower learning. Understanding structural plasticity requires identification of physical mechanisms that lead to formation new synaptic connections. Like as synaptic plasticity structural plasticity is controlled by neuronal activity. Neuronal activity controls metabolic process in neurons through calcium influx through voltage dependent calcium channels.
The model for description of activity dependent synaptic connections wiring in neural networks is based on the following experimental data (1)-(3) and assumption (4)-(5):