[Behavior of mice with robertsonian translocations of chromosomes]. / Povedenie myshei s robertsonovskimi translokatsiiami khromosom.

The behaviour of mice with normal karyotype and those with robertsonian translocations was studied. The ability of the animals to solve an extrapolatory task was analysed. The experimental procedure was initiated with presentation of a food bait which the animal could reach only through a small opening in a screen. As the mouse started drinking, the food cup was moved leftward or rightward disappearing from the animal's view. The problem was to move in the direction of food, in which case the mouse could find it behind one of two feeding holes, to the right or to the left of the starting point. Laboratory mice were not able to solve this problem, whereas mice containing Rb(8, 17)1 IEM in karyotype demonstrated the extrapolatory ability - they solve the task correctly in a significant majority of cases. By means of a series of backcrosses of Rb(8, 17)1 IEM carriers on CBA strain (these mice have no extrapolatory ability) and subsequent inbreeding, a novel inbred strain was obtained, coisogenic to CBA and possessing the robertsonian translocation Rb(8, 17)1 IEM. These mice with the CBA genetic background solve the extrapolatory problem successfully, the level of correct choices being significantly above the 50% chance level. At the same time, their performance was lower than that of outbred mice with Rb(8, 17)1 IEM, the phenomenon possibly being the result of the influence of CBA genetic background. Mice with Rb(8, 17)6 Sic were also shown to possess the extrapolatory ability.(ABSTRACT TRUNCATED AT 250 WORDS)

[The capacity of dogs to solve problems by operating with the empirical dimensions of figures]. / Izuchenie sposobnosti sobak k resheniiu zadach po operirovaniiu émpiricheskoi razmernost'iu figur

An investigation was made into the dogs capacity for operating with empirical dimensions of figures, i.e. the animal's capacity for solving problems based on the fact that out of two figures a volumetric bait can be placed only in a volumetric figure and not in a flat one. In experiments using two methods (single and multiple presentations of figures, each time of a new pair), the dogs were incapable of solving the problems. They were able, however, to elaborate in the course of learning a visual differentiation of a volumetric figure from a flat one, which implies the formation of a generalization of the volume cue as the only invariant in all the pairs of figures. The investigation into operation with empirical dimensions of figures as one of the objective parameters in estimating elementary reasoning activity of animals indicates that by this criterion dogs range in the philogenetic series by far lower than the previously studied marmoset monkeys and dolphins.

[Ability of birds of the Corvidae family to operate by the empirical dimensions of figures]. / Sposobnost' k operirovaniiu émpiricheskoi razmernost'iu figur u ptits semeistva Corvidae.

The reasoning ability was investigated in 29 Corvidae birds. The experimental task consisted in finding a hidden bait, the task being based on the fact that volumetric bait could be hidden in a volumetric geometrical figure only and not in a flat one. Thus it was possible to value the bird's ability to operate the empirical dimensions of objects. It was found that although the structure of bird brain is basically different from that of mammals, Corvidae surpass carnivorous mammals (dogs and cats) in solving this problem, their ability to operate the dimensions of objects being developped almost as well as that of monkeys.

[Features of the dynamics of the forebrain EEG of Emys orbicularis during the solving of an extrapolation problem]. / Osobennosti dinamiki EEG perednego mozga bolotnykh cherepakh pri reshenii ékstrapoliatsionnoi zadachi.

Sharp EEG changes are recorded in bioelectrical activity of the dorsal cortex and dorsal ventricular edge in marsh tortoises in conditions of free movement during solving of an extrapolation task (a test of elementary reasoning ability). These changes of a pathological character, accompanied by neurotic states, were observed in some animals having correctly solved the task several times in succession (2-5), beginning with the first presentation. Such changes of EEG and behaviour were not found in tortoises that committed errors at first presentations of the task and only gradually learned correct solving. Formation of the adequate behaviour can proceed by two means: on the basis of elementary reasoning ability and learning. Disturbance of adequate behaviour in the experiment with characteristic changes of EEG testifies to a difficult state of the animal during solving of the extrapolation task.

[Physiological and genetic ways of studying the extrapolation capability of mice]. / Puti fiziologo-geneticheskogo issledovaniia sposobnosti k ékstrapoliatsii u myshei.

Elementary reasoning--the ability of mice to extrapolate the direction of alimentary stimulus movement--was investigated in gentically different groups of animals. It was shown that mice possessing. Robertsonian translocation Rb(8,17) 11EM were superior in the extrapolation task solving than mice with normal kariotype, or mice with Robertsonian translocations of other types (RB(5, 19)1Wh, Rb(6, 15)1ALD, Rb(9, 14)6Bnr, Rb(16, 17)7bnr). Mice selected for low brain weight were superior in the extrapolation task solving than mice with high brain weight in 3--11 generations of selection. In F12--F14 this difference was absent. Mice with Robertsonian translocations and mice selected for brain weight are perspective models for physiological and genetic study of elementary reasoning.

[Features of higher nervous activity in mice with Robertsonian chromosomal translocations]. / Osobennosti vysshei nervnoi deiatel'nosti myshei s robertsonovskimi translokatsiiami khromosom.

The ability of laboratory mice to learn to solve a simple food searching task, and their ability to extrapolate the direction of stimulus movement, were investigated in animals of CBA inbred strain (64 mice) and in mice with Robertsonian fusion of 8 and 17 chromosomes -- Rb (8, 17) 1 IEM possessing different genetic background (122 mice). As the ability for extrapolation is tested while the animal has no previous experience of such task solving, this form of behaviour seems to be different from conditioning. Mice with Rb (8, 17) 1 IEM but not CBA mice proved to be capable to solve the extrapolatory task at its first presentation. Their learning ability was found to be also superior to that of CBA mice. The present data proved that mice with Rb (8, 17) 1 IEM translocation may serve as a very promising model for investigation of complex behaviour patterns.

[Effect of hyperbaric oxygenation on animal deaths from acute circulatory disorders caused by intense cerebral excitation]. / Vliianie giperbaricheskoi oksigenatsii na smertnost' zhivotnykh ot ostrykh narushenii krovoobrashcheniia, vyzvannykh rezkim vozbuzhdeniem mozga.

Sound exposure to 100--120 dB caused death of about 6--16% of white rats KM line from the blood circulation disturbances. The hyperbaric oxygenation (2 atm) decreased the death rate among rats of 4 to 15 months old while having no effect upon younger ones (2--4 months old). The rats who died in hyperbaric oxygenation suffered from O2 intoxication more often than those who survived. Administration of caffeine reduced the positive effect of hyperbaric oxygenation.