“Object permanence” test for rats. First experiments

The description of the developed experimental set, permitting to evaluate rats solution of the “object permanence” test (be J. Piaget), which reflects animal capacity to operate one of the most simple empirical rules (by Krushinsky), i.e. capacity to solve elementary logic task. An animal, being placed in the brightly lit part of the box, is eager to run into the dark one via underpass, although after the first attempts the underpass was hidden by several means, and now an animal can solve the task overcoming the obstacle in case it operates the object permanence rule. The test solution does not require the previous learning, and it is similar to the test used in mice experiments. The test was applied in experiments with rats of five genetic groups – outbred Wistar and Long-Evans rats, rats of inbred audiogenic-prone Krushinsky – Molodkina (KM) strain, the strain derived from KM rats, selected for audiogenic non-proneness and inbred SHR strain with spontaneous arterial hypertension. The preliminary experiments (performed with an animal during one experimental day) revealed interstrain differences with the test solution prevalence in SHR strain. This test could be used in pharmacological and neurophysiological experiments with rats.