[Possibilities of detecting the plasticity of monosynaptic excitable connections during the analysis of impulse activity of neurons using cross-correlation histograms and Cox's method].

By the method of mathematical modelling, stationary irregular exogenous impulse activity of two monosynaptically connected neurones (N1 and N2; excitatory connection) was reproduced. The degree of impulse flows N1 and N2 dependence was estimated by the value P12, proportional to the height of crosscorrelation histogram peak, and by Cox's coefficient beta 12. The dynamics was studied of P12, beta 12 and of values P1* and P2*, proportional to mean interpulse intervals of N1 and N2, at changes of connection efficiency, neurones excitability and of influence of afferent synaptic bombardment on them. The following signs of modification of existing between N1 and N2 monosynaptic excitatory connection were established: 1) change of P12 in direction opposite to that of P1* and P2* change; 2) differently directed changes of beta 12 and P2* of postsynaptic N2.