ИСТИНА

The mouse strains, selected for “plus” and “minus” puzzle-box solution, are now at F9 “stage”. The puzzle box test @evaluates the ability of an animal to use the “object permanence” rule (the object perceived recently could be found even if not seen anymore). The statistically significant interstrain differences are still present between “plus” and “minus” strain mice in test presentations when the underpass (leading to safe dark box compartment) was blocked by a (removable) plug. In F6, F7 and later the differences were found also in the neophagophobia test (new food in new environment) as well as in the test on attention. During the latter test an animal is presented with an object, which moves along the circular experimental box. The approaches to this object as well as exploration behavior were registered during the object presentation. There were 5 different object (plastic toys, small plastic spoon and discs) shown to animals in the chance sequence. The expression of active attention in mice of “plus” strain was higher (indexed by different variables), than in “minus” mice. The comparison of recent memory in mice of F5-F8 also demonstrated that in “plus” strain this character had higher scores, than in “minus” mice. The increased attention scores reported here are another evidence of the prevalence in cognitive traits expression in selected strain “plus”. Earlier we described that while trying to penetrate into the dark compartment of the puzzle-box “plus” mice removed the plug successfully, while “minus” mice failed to do so in significantly higher proportions of cases. Although “minus” mice tried to do so - they actively manipulated the plug, but were unable to remove it. We may conclude that that both – plus and minus mice “understand” the object permanence rule, as they try to use the hidden underpass. But only “plus” strain animals were able to realize such solution. Together with increased attention abilities this could mean that “plus” mice are superior in “executive” functions expression.