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.     

Patterns in the transition from normal to neurosis in dogs with different typological traits in food and defensive situations

At comparison of the formation of neurosis in dogs with different typological characteristics in conditions with alimentary and pain reinforcement, a resemblance was revealed of transition from norm to the initial stage of pathology. In strong animals a development was seen of compensatory tachycardia at circular changes of conditioned activity. Weak type dogs are characterized by a lowering or full disappearance of reflexes in combination with bradycardia. The method of differentiation, allowing in situations with alimentary reinforcement to classify the tested animals according to the type of higher nervous activity and differentiate the states of "norm" and "initial stage of neurosis", proved to be effective for the analogous aims also in studies with defensive reinforcement.     

Individual typological characteristics of higher nervous performance and asymmetry of hippocampus and amygdala electrical activity in dogs

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 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).     

Interhemispheric asymmetry and the typological characteristics of the nervous system in rats

The paper is devoted to studies of interrelations between behavioural dominance of the left or right hemisphere and typological characteristics of the nervous system in rats. Rats with a strong type of nervous system are shown to possess species-specific interhemispheric asymmetry. In animals with a balanced nervous system it is greater than in animals with an unbalanced nervous system. Rats with a weak type of nervous system have no species-specific interhemispheric asymmetry.     

The type of higher nervous activity in twins]

Exmination of twelve pairs of monozygote (MT) and dizygote (DT) twins and their control groups revealed an identity of the higher nervous activity type and a high positive intrapair and group correlation of typological parameters in MT (0.42); a predominantly different typological classification and a lower correlation in DT (0.33); a low correlation in the control group No. 1 and mere traces of general positive correlation in group No. 2 (0.07) and No. 3. The data point to the considerable genetic dependence of the higher nervous activity type; they also serve as a verification of the method used.     

Activity of key redox enzymes in rabbits with different typologic features

It has been found that the activity of LDG, PDG, IDG, SDG, NADN-DG, NADFN-DG, CO, G-6-FDG and 6-FGDG in the cerebral cortex, liver and kidneys of rabbits with a strong type of nervous activity, as a rule, is higher than in the animals with a weak type of the nervous system. Between the animals with different types of the nervous system distinctions are also revealed in the character of regulation of a number of metabolic cycles. It is suggested that typological features of the nervous system are determined by the character of metabolic processes.     

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]

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.     

Electroencephalographic characteristics in animals with different typologic characteristics of their higher nervous activity]

Manifestation of typological characteristics of higher nervous activity in EEG energo-(amplitude-) frequency parameters were studied in chronic experiments on cats in a state of rest. EEG Of the animals of a strong nervous system type were characterized by a comparatively steady prevalence of alpha-activity and a stable relationship between the summary energy parameters of the basic frequencies. The brain electrical activity of cats with a weak type of higher nervous activity was in some cases characterized by instability of the general pattern: the summary parameter of each rhythm often changed, while at different intervals of time any of them could be recorded as predominant; in other cases slow waves were steadily prominent, and the summary energy of alpha-activity was low.     

EEG and success in learning the job of autotransport driver in persons with different typologic characteristics of the nervous system

The properties of nervous processes: mobility and strength (capacity for work), were determined by the Khilchenko method in healthy subjects learning the trade of an automobile driver. People with different individual typological characteristics of higher nervous activity displayed significant differences in EEG energo-frequency parameters of different brain areas. It has been shown that EEG of practically healthy people at rest, in conjunction with other informative psycho-physiological data, offers promise for appraising the individual typological characteristics of a person in predicting the professional suitability for driving automobiles.     

The effect of an extra-stimulus on successive inhibition following differentiations]

The influence of a foreign stimulus on the aftereffect of inhibitory stimuli was studied in experiments on dogs with salivary conditioned reflexes. The dynamics of temperature changes in the parotid salivary gland was used as an indicator since the action of a differentiation stimulus was accompanied by a drop in its temperature; each differentiation, whether rough, medium or fine--had its own limit of the gland's temperature drop during intensification of differentiation inhibition. It has been found that the dynamics of the gland temperature changes in the trace pauses and in response to a foreign stimulus depends on the modality of the stimulus, the duration of its action in the experiment, the typological properties of the animal's nervous system and the fineness of differentiation.     

Stress and immunity: an integrated view of relationships between the brain and the immune system

The old notion that stress exacerbates the progression of physical illness via its corticosteroid-mediated immunosuppressive effects must be revised. Experimental and clinical studies demonstrate that both laboratory and natural stressors alter the activities of lymphocytes and macrophages in a complex way that depends on the type of immune response, the physical and psychological characteristics of the stressor and the timing of stress relative to the induction and expression of the immune event. The influences of stress on immunity are mediated not only by glucocorticoids but also by catecholamines, endogenous opioids and pituitary hormones such as growth hormone. Sensitivity of the immune system to stress is not simply fortuitous but is an indirect consequence of the regulatory reciprocal influences that exist between the immune system and the central nervous system. The immune system receives signals from the brain and the neuroendocrine system via the autonomic nervous system and hormones and sends information to the brain via cytokines. These connections appear to be part of a long-loop regulatory feedback system that plays an important role in the coordination of behavioral and physiological responses to infection and inflammation.     

Typological characteristics of dogs in the initial period of the development of neurosis

In the initial period of neurosis, significant differences were found in changes of motor and vegetative reactions in dogs of dissimilar typology. Animals with strong type of the nervous system displayed cyclic transitions from the normal state to the initial stage of pathology and vice versa. Such transitions were practically absent in dogs of the weak type. A method is proposed providing efficient classification of experimental dogs according to their types of higher nervous activity and differentiation of the normal state and the initial stage of neurosis.     

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.     

心率变异性评估运输应激对Beagle犬自主神经功能的影响

目的 基于心率变异性(heart rate variability,HRV)分析评估运输应激对Beagle犬自主神经功能的影响,并界定其恢复期.方法 16只Beagle犬随机分成两组(每组8只),即对照组和运输应激组,利用大动物无创生理信号遥测技术,分别监测清醒自由活动状态下对照组和运输应激组应激4 h后、恢复1、2、...     

Individual sensitivity of Wistar rats to piracetam

Effects of repeated piracetam (PIR) injections in a dose of 40 and 250 mg/kg/day on the learning in Water rats were studied. It has been found that character of the effects depends on typological features of the animals. Rats with strong predominance of excitation (choleric type) showed low sensitivity to PIR. Small dose of PIR provoked clear negative effect in rats with relative balance of the basic nervous processes: excitation and inhibition (sanguine and phlegmatic types). Despite of expressed activation of associative process, it complicated integrative activity. Small dose of PIR showed anxiolytic and psycho-stimulant actions only in initially unlearned rats characterized by high level of fear. Large dose of PIR had negative influence on the learning process in all animals, irrespective of typological features. Thus, the results of this study allow to suppose that the individual sensitivity of an animal to action of a pharmacological medication is caused by morpho-functional and neurochemical intraspecific heterogeneity.     

Radiation physiology of higher nervous activity: results and perspectives

Reflex forming and stabilization, the typological peculiarities of the experimental animals' higher nervous activity were discussed. The problems of the central nervous system functional reactions to irradiation in small doses, the chronic irradiation in particular, influence to higher nervous activity of heavy particles irradiation and neurochemical mechanisms of the disturbances in the central nervous system require further experimental investigations.     

The influence of examination stress on psychophysiological characteristics and heart rate in students

With the aim to assess the influence of pre-examination psychoemotional stress on the level of centralization of the heart rate control, mathematical analysis of ECG of students was performed in normal condition (a common day of academic semester), before, and after an examination. The ECG was recorded and processed with the help of IBM-486 PC. R-R cardiointevalograms were processed by the method of variational pulsometry after Baevsky. Common quantitative heart rate indices were studied. The level of anxiety of students was assessed by Spilberger, and subjective estimations of general condition, activity and mood were obtained from the respective questionnaire. Three types of heart rate reactions on the examination stress were revealed. The reactions depended on the individual typological characteristics and the state of autonomic nervous system.     

Feedback and the typological characteristics of higher nervous activity]

Apparatus of the theory of automatic regulation and control systems is applied for explanation of typological characteristics of the higher nervous activity. On the basis of the analysis of activity of four types of automatic control systems a hypothesis is suggested that these characteristics are connected with organization of the feedback in the functional system, and analogies drawn between the types of the higher nervous activity and types of automatic systems.     

Typological characteristics of conditioned reflex learning in monkeys

Three types of conditioned learning dynamics were singled out in males of the rhesus monkeys by the speed of formation of a positive motor instrumental reflex and differentiation. Type I is characterized by the fastest mastering of separate subprograms and of the whole test program of conditioned behaviour, by optimal functional characteristics in the process of learning and by a high adaptivity in new conditions. The most prolonged formation of the conditioned reflexes occurs in monkeys of the III-d type; 50% of them do not master the whole learning program; monkeys with such type of learning dynamics have no adaptation of previously acquired conditioned stereotype to new environmental conditions. Monkeys of the II-nd type of learning dynamics possess intermediate characteristics. A notion is substantiated of interconnection of higher nervous activity properties with typological characteristics of conditioned learning dynamics in monkeys.