Biophysics of complex systems and mathematical models. Co-ordination of the limbs during running of the dog

Investigation of the kinematics of running of the dog on a treadmill allows us to draw certain conclusions which may also apply to the general case of control of movement. They are in agreement with the statement of Bernshtein on the multi-level mechanism of construction of movement [5] and the concepts of Gel'fand, Gurfinkel' and Tsetlin [6] on the use of interaction between the controlled elements in the task of control. Previous studies [1, 2] yielded information suggesting that during natural motor activity-locomotion-definite linkages are superimposed on the apparatus of control of the joints of one limb. This makes it possible to control a smaller number of independent parameters than the number of joints (muscles) involved in running. Probably, in different motor tasks these linkages may differ. After the linkages have been superimposed on the apparatus of control of the joints of one limb the task of construction of running boils down to inter-limb co-ordination. The results of this work make very plausible the assumption that for this co-ordination inter-limb interaction is of fundamental importance. It may also be assumed that within one class of movement, for example, running at different speeds, the main scheme of interaction of the limbs remains unchanged. The quantitative changes in this interaction may be sufficient to obtain different patterns of movement best corresponding to the current conditions. It is also possible that there are comparatively few different schemes of interaction of the muscles during motor activity. Then it would suffice to assign the main scheme to the higher sections of the nervous system (possibly even leaving the choice of the parameters of interaction to autonomous mechanisms) in order to obtain adaptive motor activity.