[Analysis of the free behavior of an animal based on its probabilistic characteristics].

It is shown that the process of rat behaviour in probabilistic media ("open field" test) corresponds to the basic conditions which determine the concept of the Markov continuous chain. To characterize the degree of orderliness (non-orderliness) of the integrated behavioural activity, the parameter of the Markov process entropy may be used. Dependence has been found between the level of behaviour entropy and individual characteristics of the organization of orienting-investigating activity of rats in the "open field" test.