PubMed HealthSearch

Biomedical subjects

L P Rudenko

Publications and source records attributed to L P Rudenko.

At least 19 recordsLinked to original sources

On the mechanisms of the formation of backward connections.

In a study carried out on dogs by Pavlov's methods of classical and instrumental alimentary conditioning the influence of the duration of intervals between paired stimuli has been shown on the manifestation of backward connections: the shorter the interval the more distinct their manifestation. The percentage of Backward connections was much higher after multiple reinforcements than after a single one. The effects of interval duration as well as of repeated presentation of paired stimuli on backward connections show that these factors are of considerable importance for their formation.

Animals

On the functional stucture of conditioned reflexes to serial stimuli in dogs.

The functional structure of conditioned reflexes to a stimulus series has been studied. The serial stimulus consisted of a tone of 600 Hz, passive lifting of the right forepaw, and a puff of air directed at the eye, the latter component of the series being reinforced by food. Four dogs were wed. Objective registration of the effector manifestations to each component stimulus has shown that, during the elaboration of a conditioned alimentary reflex to the serial stimulus, conditioned connections are formed by each component with the alimentary center and by each preceding stimulus with all subsequent stimuli, irrespective of their position in the series. All excitation foci which function in the given stimulus set become interconnected. Direct connections of each stimulus component with the alimentary center are never inhibited. The multiplicity of duplicating direct connections and the presence of backward connections impart to composite reflexes the reliability and adaptive strength which is necessary for the formation of behavioral acts.

Animals

[The relation of the typological classification of dogs to their behavioral characteristics in variations between the probability and the value of reinforcement].

In studying of dogs behaviour in coordinates system "Requirements and probability of their satisfaction" it has been established that selection of behaviour strategy is closely connected with individual typological properties of animals. In experiments with equally-probable alimentary reinforcement a direct correlation was found between the strength parameter of the nervous system and the strategy of dogs behaviour. Animals of strong types manifested the character of reaction which consisted in determination and goal-directedness, while the animals of the weak type manifested other character, having features of uncertainty, indefinition, hesitations. In conditions of conflict between probability and value of reinforcement the dogs manifested two opposite strategies of behaviour: orientation to highly probable events (choleric and phlegmatic) and to low-probable events (sanguinic and melancholic) what is connected with individual properties of functioning and the character of interaction of four brain structures (frontal cortex, hippocampus, hypothalamus, amygdala).

Animals

[Individual behavior characteristics of dogs in conflict between the probability and the quality of reinforcement].

In experiments on dogs with equiprobable right and left reinforcements in the choice of feeder in conditions of free behaviour, direct correlation was found between the strength of the nervous system and the strategy of dogs behaviour. The dogs of strong type, despite the difference in equilibration and lability, manifested one, similar strategy of behaviour with dominating preferences, definite and goal-directed actions; the dogs of the weak type displayed another strategy, characterized by uncertainty, permanent hesitations in choice reaction. In situation of competition of probability and value of reinforcement, some different aspects of animals typology appeared, presumably connected with individual characteristics of functioning of four brain structures as a basis of types of higher nervous activity (frontal cortex, hippocampus, amygdala, hypothalamus). Behaviour of choleric and flegmatic was oriented to a high probability of events and that of sanguinic and melancholic--to a low one. Thus, "informational" and "motivational" factors of behaviour organization are connected with interaction of specialized brain macrostructures, and properties of this interaction become apparent in animals typology.

Animals

[Natural 1st and 2d degree conditioned food reflexes in the dog in relation to space orientation].

In three dogs formation and performance of spatial alimentary natural conditioned responses of the second order was studied when the dog had to find food preliminarily shown to it in one of the four food-distributors (psychonervous activity directed by a food image in terms proposed by I. S. Beritashvili). Characteristics of this form of behaviour were demonstrated and discussed: rapid formation, dependence of performance on the delay time, conflict between responses of the first and the second order. In the second series of the experiments food-procuring behaviour of dogs was studied under conditions of conflict between the quality (value) of alimentary reinforcement and probability of its finding in certain food-distributor. Such kind of behavior was shown to depend on the motivation level and individual characteristics of the dog. Interaction of "informational" (anterior areas of the neocortex, hippocampus) and "motivational" (nuclei of amigdalar complex, hypothalamus) cerebral structures is supposed to underlie the organization of behaviour.

Animals