Correlational association between changes in cell excitability and synaptic efficiency during posttetanic reorganizations in the cortex.

A positive linear association between the posttetanic changes in synaptic efficiency and the shifts in the cellular excitability observed at the same time was established using the method of calculation of the coefficient of correlation (CC) between the changes in the direct and synaptic components of the response of the pyramidal tract. The CC values found at the initial stages of the formation of the trace process decrease with time, and a significant correlational association between the changes in the components is absent by an hour after the tetanic stimulation. Such temporal specificity in the contingency of the mechanisms studied presupposes at a certain stage in the organization of the trace a communality of intracellular molecular substrate which determines the manifestation of these mechanisms. Correlation analysis carried out suggests that cortical plasticity is a complex dynamic system, the understanding of which requires not only the elucidation of the elementary cellular mechanisms forming it, but the study of the character of the interaction between them as well.