Involvment of inhibitory skills in behaviour of mice subjected to detour test
BACKGROUND AND AIMS: A common test of intelligence is the detour task, where various barriers are applied to prevent animals from reaching a goal. However, there is no information available about the effect of goal visibility on rodent behavior and about the involvement of inhibitory skills and physical cognition in performance of rodents faced with the detour problem. Therefore, we tested the effect of target visibility both in naïve mice and in subjects that already had an experience in detouring obstacles. METHODS: The subjects were F1 hybrid (C57BL10×CBA/H) male mice. The water escape paradigm was used to motivate mice to detour the barrier. The apparatus consisted of circular tank and visible platform. Transparent, semitransparent and opaque barriers were used to prevent animals from reaching their goal. RESULTS: We have found that naïve mice tested with transparent barrier displayed high level of perseveration. In contrast, mice that were initially trained with opaque or semitransparent barriers displayed no deficits during tasks applying transparent barrier. Improvement in both transparent and semitransparent groups was associated with changes in path direction. We have also found that mice displayed consistent lateralization during inward and outward detour trials. CONCLUSIONS: We have found that both inhibitory skills and physical cognition affects performance of mice subjected to the detour task. The difficulty to inhibit proponent responses interfered with the ability of mice to find the proper solution. We have also found that mice followed their respective left or right side instead of using landmarks to navigate during the test. Obtained results show for the first time that behavior of mice subjected to the detour task is comparable with the behavior of other species including human infants and monkeys.