Subcortical nerve centers

The activity of the subcortical nerve centers is determined on the basis of the relative powers of the respiratory waves and waves of the first and second-order (S2 / S, S1 / S, Sd / S, where S = S2 + S1 + Sd) with the allocation of states of pronounced and moderate increase in the activity of the subcortical nerve centers, normal activity of the subcortical nerve centers, moderate and pronounced weakening of the activity of the subcortical nerve centers.

Source: http://csp-athletics.ru/images/doc/metod/control/metod-control-10.pdf