[Individual prognostic behavioral features in dogs during the choice between probability and value of reinforcement].

A strategy and latency of choice between the probability (100, 50, 30, 20 and 0% probabilities were tested) and value (high and low) of the reinforcement were investigated in dogs. The greatest differences in dogs' behavior were observed under conditions of uncertainty when the valuable reinforcement was presented with probabilities from 50 to 20%. According to subjective evaluation of uncertain situation, dogs were divided into "inclined to risk" (more frequently choosing low-probable but valuable food) and "careful" (more frequently choosing high-probable but less valuable food). The choice of less probable reinforcement, especially under conditions of increasing uncertainty, was performed with longer latency that the choice of the 100%-reinforcement, which points to the strengthening of cognitive processes under conditions of a "difficult choice". The situation of uncertainty increased the emotionally negative state of the dogs (whimper, refusal of meal, etc.).

[Age-related and individual psychological differences in student behavior under conditions of the reward choice].

Strategies of behavior of choice between the probability (100-0%) and value of the reward (scored as 1-5 or 6-10 on a 10-point scale) depending on the traits of impulsivity/reflectivity, anxiety, and emotional state were studied in schoolchildren at the age of 7-8 (form 1-2), 9-10 (form 3-4), and 11-14 (form 5-7). Differences in behavioral strategies were highest among the children who "worked" under conditions of 50-10% probability of getting a valuable reward. Children who more frequently chose lower scores but occurring with the highest (100%) probability were referred to as "careful", and those who chose higher scores with lower probability were referred to as "inclined towards risky behavior" ("risky"). On this principle, schoolchildren of each age group were assigned to "risky", "moderately risky", moderately careful", and "careful" groups. Individual-psychological differences between the groups were more pronounced at the age of 11-14 years than at the age of 7-8 years. Under conditions of 25% probability of getting a valuable reward, differences in behavioral strategy were essential between the "risky" and "careful" group; under conditions of 10% of probability, the differences between the "moderately risky" and the remaining groups were most pronounced. Choice of a reward received with lower probability under conditions of uncertainty (50-10%) was performed with longer latency than the choice of the reward received with 100% probability. There were more "careful" children in the 3th-4th forms, a "moderate inclination to risky behavior" prevailed in the 5th-7th forms. From the 1st to 7th form, impulsivity prevailed in children "moderately inclined to risk", whereas there were more reflective children in "careful" and "moderately careful" groups. Choice behavior had an impact on the emotional state of children. Heart rate increased after the choice performance. In "careful" children scores of personal and class anxiety were higher than in the "moderately risky" group.

[Significance of motivation balance for a choice of dog's behavior under conditions of environmental uncertainty].

Two experimental models with a choice between two reinforcements were used for assessment of individual typological features of dogs. In the first model dogs were given the choice of homogeneous food reinforcements: between less valuable constantly delivered reinforcement and more valuable reinforcement but delivered with low probabilities. In the second model the dogs had the choice of heterogeneous reinforcements: between performing alimentary and defensive reactions. Under conditions of rise of uncertainty owing to a decrease in probability of getting the valuable food, two dogs continued to prefer the valuable reinforcement, while the third animal gradually shifted its behavior from the choice of a highly valuable but infrequent reward to a less valuable but easily achieved reinforcement. Under condition of choice between the valuable food reinforcement and avoidance of electrocutaneous stimulation, the first two dogs preferred food, whereas the third animal which had been previously oriented to the choice of the low-valuable constant reinforcement, steadily preferred the avoidance behavior. The data obtained are consistent with the hypothesis according to which the individual typological characteristics of animals's (human's) behavior substantially depend on two parameters: extent of environmental uncertainty and subjective features of reinforcement assessment.

[Features of differential inhibition in choice between alimentary and defensive response].

Instrumental defensive (avoidance/escape) and alimentary responses (reinforced with palatable food) in dogs were conditioned by the same stimulus (6-Hz light flashes). Differential inhibition for these responses (0.6-Hz flashes) was formed in unalterable series. Later on, alternative experiments with choice between reinforcements were carried out. In both of experimental series, the degree of alimentary excitability (hunger, satiation) was changed. Numbers of responses to differential and positive conditioned stimuli and their latencies were calculated. Under condition of choice (electrodes on a leg and a pedal in front of a dog) the response depended on a dominant motivation. The dogs differed in the degree of motivation dominance. Differential inhibition was less perfect in unalterable experimental series with dominant motivation. Under conditions of choice between alimentary and defensive reinforcements, the response to the differential stimuli depended on the balance between these motivations: two days of hunger increased the number of alimentary responses, defensive responses prevailed after satiation.

[Individual typological features of the dog behavior during the choice between food and avoidance of electrocutaneous stimulation].

Two conditioned reflexes (CR) on flash were elaborated in five dogs in three experimental series. In one of them pressing on pedal were constantly reinforced with two pieces of liver, in other--escape or avoidance of skin stimulation with lifting of leg. In a third series, series of reinforcement choice, in front of animal with electrodes, fasting on leg, put the pedal. During of choice series defensive reactions were dominated in two dogs, alimentary reactions--three of them. For restoration alimentary behaviour in dog with great dominating of defensive reactions were many times reinforced with--food "passive" pressing legs on pedal during conditional stimuli, dog with less dominating of these reactions for restoration were enough a few coupling of conditional stimuli with food. With intensification electrocutaneus stimulation of legs or decreasing alimentary reinforcement we a success of diminishing of degree of alimentary reaction domination in one dog and in other ones temporarily changed of these domination on prevalence of defensive reactions. The results were compared with data, obtained in these dogs with technique of choice between probability and value of alimentary reinforcement. This comparison were permitted us of ranging dogs on scale "carefulness-riskiness", revealed of individual typological features of these animals.

[Choice between probability and value of alimentary reinforcement as means for revealing individual typological features of dog behavior].

Individual typological features of behavior of dogs were investigated by the method of choice between the low-valuable food available constantly and food of high quality presented with low probability. Animals were subjected to instrumental conditioning with the same conditioned stimuli but different types of reinforcement. Depression of a white pedal was always reinforced with meat-bread-crumb mixture, depression of a black pedal was reinforced with two pieces of liver (with probabilities of 100, 40, 33, 20, or 0%). The choice of reinforcement depended on probability of valuable food and individual typological features of the nervous system of a dog. Decreasing the probability of the reinforcement value to 40-20% revealed differences in behavior of dogs. Dogs of the first group, presumably with the weak type of the nervous system, more frequently pressed the white pedal (always reinforced) than the black pedal thus "avoiding a situation of risk" to receive an empty cup. They displayed symptoms of neurosis: whimper, refusals of food or of the choice of reinforcement, and obtrusive movements. Dogs of the second group, presumably with the strong type of the nervous system, more frequently pressed the black pedal (more valuable food) for the low-probability reward until they obtained the valuable food. They did not show neurosis symptoms and were not afraid of "situation of risk". A decrease in probability of the valuable reinforcement increased a percentage of long-latency depressions of pedals. It can be probably suggested that this phenomenon was associated with increasing involvement of cognitive processes, when contributions of the assessments of probability and value of the reinforcement to decision making became approximately equal. Choice between the probability and value of alimentary reinforcement is a good method for revealing individual typological features of dogs.

[Individual typological characteristics of higher nervous performance and asymmetry of hippocampus and amygdala electrical activity in dogs]. / Individual'no-tipologicheskie osobennosti vysshei nervnoi deiatel'nosti sobak i mezhpolusharnaia asimmetriia élektricheskoi aktivnosti gippokampa i mindaliny.

Electrical activity of the frontal cortex, dorsal hippocampus, basolateral amygdala and lateral hypothalamus of both hemispheres was recorded in nine dogs in the state of quiet wakefulness without any stimulation. Individual typological features of higher nervous activity were assessed by the animal performance under conditions of free choice of the reinforcement mode: either high probable but of low alimentary quality, or with low probability but more valuable. Mean values of the maxima of crosscorrelation function between electrical activity of the investigated structures of two hemispheres were used as a basis for assessment of conditions for interaction between left and right formations. For the hippocampus and amygdala, in some dogs these conditions were the best in the theta and beta 2 ranges, in other animals--in the theta and alpha bands. In phlegmatic dogs, spectral densities in the theta range were higher in the left hippocampus than in the symmetrical structure, in sanguine animals spectral densities in the theta and beta 2 ranges in the hippocampus and amygdala were higher in the right hemisphere than in the left one. Thus, the hemispheric asymmetry of electrical activity of the limbic formations seems to be an important factor, which determines the individual typological features of the higher nervous activity in dogs.

[The typological characteristics of higher nervous activity in dogs and the maxima of the cross-correlation function between the electrical activities of the frontal cortex and the brain limbic systems]. / Tipologicheskie osobennosti vysshei nervnoi deiatel'nosti sobak i maksimumy funktsii krosskorreliatsii mezhdu élektricheskoi aktivnost'iu frontal'noi kory i limbicheskikh struktur mozga.

Electrical activity of the frontal cortex, dorsal hippocampus, basolateral amygdala and lateral hypothalamus was recorded in eight dogs with chronically implanted electrodes. Mean values of the maxima of crosscorrelation function (MCCF) between electrical potentials in the theta, alpha and beta-2 ranges were used as a basis for assessment of conditions for interaction between these structures. Typological features of the higher nervous activity were assessed by the animal performance under conditions of free choice of the reinforcement mode of a conditioned stimulus: either high probable but of low alimentary quality or with low probability but more valuable. The mean MCCF values in the theta range were higher than in the other ranges. The brain structure which had the high MCCF in the theta-range, at least, with two of the structures under study was considered as "dominant". It was shown that hippocampus was the dominant structure for melancholic dogs, the frontal cortex was in phlegmatics. The hypothalamus was shown to be the "dominant structure" in both sanguine and choleric animals, but, for the most part, its activity was correlated with different structures. Thus, conditions for interaction between the frontal cortex, hippocampus, amygdala and hypothalamus seem to be an important factor, which determines typological features of the higher nervous activity of dogs.

[I. P. Pavlov's theory on higher nervous activity: the landmarks and trends in its development]. / Teoriia I. P. Pavlova o vysshei nervnoi deiatel'nosti: vekhi i tendentsii razvitiia.

The theory of higher nervous activity created in Pavlovian time is compared with the present-day state of the theory developing due to appearance of new methods, techniques, facts, and concepts. Three principles of Pavlovian theory: determinism; analysis and synthesis; structural approach, as well s types of conditioned reflexes and techniques, types of higher nervous activity, and inhibition problems are discussed. The theory of higher nervous activity is schematically depicted as a tree, some branches of which are presented by facts and concepts obtained and introduced by I.P. Pavlov and his followers during his life, the others are formed by new facts and concepts advancing the theory. What is obsolete in the theory, what are the most prominent tendencies of its development and its new branches are discussed.

[The effect of anxiolytics and an anxiogen on the electrical activity of the frontal cortex and limbic structures of dogs with different nervous system properties]. / Vliianie anksiolitikov i anksiogena na élektricheskuiu aktivnost' frontal'noi kory i limbicheskikh struktur sobak s raznymi svoistvami nervnoi sistemy.

The influence of benzodiazepine anxiolytics (diazepam, medazepam, nozepam) and anxiogen corasole on the electrical activity of the dorsal hippocampus, frontal cortex, basolateral amygdala, and lateral hypothalamus was studied in 8 dogs with implanted electrodes. The anxiolytics decreased anxiety and reduced the theta-rhythm frequency in all the structures under study. The effect was most pronounced in the dorsal hippocampus. The excitable dogs with initially more frequent theta rhythm turned to be less sensitive to diazepam than more calm animals with prevailing inhibition. The higher dose of diazepam was necessary for excitable dogs to obtain the same electrophysiological effect. At the end of the drug action, the theta-rhythm power significantly increased in the dorsal hippocampus in all the animals, and in the excitable dogs it increased also in the frontal cortex. Moreover, diazepam produced as decrease in the beta 2-frequency and increase in the frequency of the alpha-like rhythm. The anxiogen intake resulted in an increase in dogs' alertness and motor activity, accompanied by an increase in the theta-rhythm frequency. Anxiogen increased the frequency asymmetry of theta between hemispheres in the hippocampus and amygdala.

[The similarity and difference between dogs assessed by the indices of the summary electrical activity of the frontal cortex, hippocampus, amygdala and hypothalamus]. / Skhodstvo i razlichie mezhdu sobakami, otsenivaemye po pokazateliam summarnoi élektricheskoi aktivnosti frontal'noi kory, gippokampa, mindaliny i gipotalamusa.

Eight dogs were bilaterally implanted with stainless steel electrodes in dorsal and ventral hippocampi (DHp, VHp), basolateral amygdala (BLA), lateral hypothalamus (LH) and with silver spherical electrodes in the frontal cortex (FC). The EEG of these structures was recorded in the state of wakefulness without any stimulation. Rhythmical activity in the theta (4.4 +/- 0.05 Hz) and alpha (10.7 +/- 0.2 Hz) ranges was revealed in all the dogs. Rhythm of the beta-2 range (22.4 +/- 0.1 Hz) was recorded in four, and that of the beta-3 (37.8 +/- 0.5 Hz) only in two of the animals. The mean frequency of the theta-rhythm recorded in the LH was higher (p < 0.001) than that in the VHp and AMB. The spectral density in the theta range was higher in the VHp than that in the other structures (p < 0.01). The same values for the DHp and AMB were higher that for the LH (p < 0.001) and FC (p < 0.01). The spectral densities in the right DHp and VHp were higher than in the symmetrical left derivations (p < 0.001). The dogs were different in the expression of specific rhythms, their frequency and power. These characteristics depended on the degree of emotional excitation and motor activity of the dogs during recording of the electrical activity.

[The autonomic component of food and defensive conditioned reflexes acquired to bursts of light and electrostimulation of the limbic structures and the basal ganglia]. / Vegetativnyi komponent pishchevykh i oboronitel'nykh uslovnykh refleksov, sformirovannykh na vspyshki sveta, élektrostimuliatsiiu limbicheskikh struktur i bazal'nykh gangliev.

Alimentary and defensive instrumental conditioned responses (CRs) to light flashes, electrical stimulation of the dorsal hippocampus and the nucleus caudatus were elaborated in seven dogs. These CRs were tested by electrostimulation of the limbic structures and the basal ganglia. Motor and vegetative components of CRs were compared. If there occurred an instrumental movement during the conditioned stimulus the heart rate increased with a high probability. If there were no movement the heart rate increase approached the level of significance only in five dogs of seven. The heart rate always increased in the positive generalization tests while in the negative ones the heart rate either decreased or increased to a lesser degree.

[The contribution of Academician L. A. Orbeli to the theory of higher nervous activity]. / Vklad akademika L. A. Orbeli v uchenie o vysshei nervnoi deiatel'nosti.

In the paper are discussed the main directions of the investigation of the higher nervous activity, fruitfully developed by academician L. A. Orbeli and his school. These directions are the following: the evolutionary approach, the study of the influence of the sympathetic nervous and endocrine systems, of the role of the extracortical brain structures, especially the hypothalamus and the cerebellum, and the significance of pain and efferent systems for the higher nervous activity.

[A collector of evoked potentials]. / Sobiratel' vyzvannykh potentsialov.

The collector is an adaptive algorithm for pattern recognition. It proposes new in-line fully-automatic technique to learn and recognize effective patterns of input data stream. Evoked potentials (EP) were recorded by ADDA 100 KHz, 4 channels, and described by 200 points per each EP. The collector recognized different studies of conditioned response (CR) by patterns of EPs in amygdalar central nucleus. In dogs with implanted into the limbic structures concentric electrodes an instrumental CR was elaborated to electrical stimulation of the dorsal hippocampus. Generalization or transfer of this CR was tested by means of electrostimulation of amygdalar basal nucleus. The generalization in the first experiment took place approximately in 86% of cases, in the second one in 52% of cases. In the first experiment the amplitudes of initial negativity and of late positive waves were smaller than those in the second one and in the experiments before conditioning.

[Evoked potentials of the brain limbic structures during a change in the motivational state of dogs and during the realization of unconditioned reflex reactions]. / Vyzvannye potentsialy limbicheskikh struktur mozga pri izmenenii motivatsionnogo sostoianiia sobak i osushchestvlenii bezuslovnoreflektornykh reaktsii.

In experiments on 6 dogs it has been shown that in the EPs led from the hippocampus in response to electrostimulation of limbic structures and from the latters at the hippocampus stimulation, initial negativity, after positivity and late negative wave are the most stable components. At transition from one functional state to another two latter waves are subjected to the greatest changes. Amplitude-temporal characteristics of intralimbic EPs depend on the level and type of motivation, degree of emotional stress and properties of conditioned reaction.

[Intralimbic evoked potentials in the formation of an instrumental food conditioned reflex to hippocampal electrostimulation in dogs]. / Vnutrilimbicheskie vyzvannye potentsialy pri formirovanii instrumental'nogo pishchevogo uslovnogo refleksa na élektrostimuliatsiiu gippokampa sobak.

In dogs with the electrodes implanted in the hippocampus, amygdala, septum and hypothalamus an instrumental alimentary conditioned reflex (CR) was elaborated to electrostimulation of the hippocampus. Intralimbic evoked potentials (EPs) were studied during the elaboration and extinction of this reflex and during stimulations of limbic structures conducted with the purpose of CR generalization checking. Late EP components in the lateral hypothalamus and central nucleus of the amygdala changed during CR elaboration and extinction and in the hippocampus during amygdala testing. In both cases the amplitude of trace positivity and of slow negative wave was less, when during stimulation of the structure an instrumental movement was initiated than at its absence.

[The role of the basal ganglia in the reproducibility of instrumental reactions acquired to electrostimulation of the hippocampus]. / Rol' bazal'nykh gangliev v vosproizvodimosti instrumental'nykh reaktsii, vyrabotannykh na élektrostimuliatsiiu gippokampa.

In dogs with electrodes implanted into the brain, a defensive instrumental conditioned reflex (CR) was elaborated to light flashes, stimulation of the dorsal hippocampus (DH) and caudate nucleus (CN) stimulation. Reproducibility of the learned movement was tested for the contralateral DN, CN, nucleus accumbens (AN) and pallid globe (PG). In the second series the percent of the elicited movements was compared to EPs, appearing in response to signal and testing stimulation. The degree was elucidated of structures participation in motivational, signal and executive links of CR. Low degree of AN participation in the executive CR link (2-nd series) and a high degree of AN and PG participation in the signal link (3-d series) were shown. Thus, intrasystemic CR generalization was more effective than the intersystemic one.

[Dependence of the electrical activity of the amygdaloid complex on motivation level and emotional status in the dog]. / Zavisimost' élektricheskoi aktivnosti mindalevidnogo kompleksa ot urovnia motivatsii i émotsional'nogo sostoianiia sobaki.

On the basis of spectral analysis of prolonged realizations (hundreds of seconds) of electrosubcorticograms of the amygdalar complexes of three dogs, the effect of increase in power of amygdalar rhythmic activity was found, at the change of motivation level in conditions of dominance of alimentary or defensive motivation independently of its kind. Resonance characteristics of the system responsible for the generation of the given rhythm remain unchanged; this allows to explain the increase of the spectral peak by the rise of the inflow of afferent impulse activity to the amygdala. At presence of competitive motivations no summation of their influences is observed; a more complex effect on the rhythm arises in the amygdala.

[The role of signal and motivational links of a conditioned reflex in the initiation of instrumental movements in dogs]. / Rol' signal'nogo i motivatsionnogo zven'ev uslovnogo refleksa v initsiatsii instrumental'nykh dvizhenii u sobak.

Alimentary instrumental conditioned reflex (CR) was elaborated in dogs to light flashes (I series), electrostimulation (ES) of the hippocampus (II series) and the hypothalamus (III series). Nonreinforced ES of the hypothalamus, amygdala, hippocampus and septum reproduced pressings on the pedal to the least extent in the I series (17-40% of trials), increasing in the II-nd one up to 40-87% during stimulation of the lateral hypothalamus, medial amygdala and contralateral hippocampus. In the III-rd series the number of pressings increased statistically significantly in comparison with the I-st series for most structures. Probably, besides the artificial increase of motivation during ES of the limbic structures which took place in all series, in the II-nd and III-rd series significance for movement reproduction was acquired by CR generalization appearing due to close interconnection of the structures. In this phenomenon connections (evaluated by the EPs) from the tested structures to the initially signal one are important.