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.     

The dependence of the rate of learning on the probability of the random performance of an acquired reaction under different regimens of aversive reinforcement in rats

Learning of rats in the process of elaboration of instrumental conditioned reflex takes place much faster at the probability of random fulfillment of correct reaction (PRCR) equal to 0.25 and 0.125 than at PRCR 0.5 and 0.05. Decrease of the frequency of positive reinforcements of correct reactions from 100 to 25% does not influence the speed of learning at PRCR 0.25 and 0.125, however significantly retards the process of learning at PRCR 0.05. There exist optimum and pessimum for learning PRCR values at different regimes of reinforcement.     

Ensemble activity of visual and frontal cortex in the conditions of choice of different value food reinforcement in cats

The method of "low choice" of food value reinforcement depending on delayed response to its reception demonstrated various strategy of behaviour, showing short or delayed responses of pressing pedal for reception of low or high value of food reinforcement. In trained cats, multiunit activity was recorded in investigated brain areas and functional interneuron interactions were subsequently analysed. Significant prevalence of interneuron interactions was revealed in "impulsive" animals in both cortical zones as well as intergroup differences during the pre-signal and signal periods in visual and frontal cortex.     

Matching-to-sample by pigeons: the dissociation of comparison choice frequency from the probability of reinforcement

It has been proposed that comparison choice in matching-to-sample should depend on two factors, the relative probability of reinforcement associated with each of the comparison stimuli and the conditional probability of each comparison stimulus being correct given presentation of one of the samples. DiGian and Zentall [DiGian, K.A., Zentall, T.R., 2007. Matching-to-sample in pigeons: in the absence of sample memory, sample frequency is a better predictor of comparison choice than the probability of reinforcement for comparison choice. Learn Behav. 35, 242-261] have shown that sample frequency together with the probability of choosing each of the comparison stimuli in training can influence comparison choice when delays are introduced, when the number of reinforcements associated with each of the comparison stimuli is equated. Furthermore, Zentall and Clement [Zentall, T.R., Clement, T.S., 2002. Memory mechanisms in pigeons: Evidence of base-rate neglect. J. Exp. Psych.: Anim. Behav. Proc. 28, 111-115] have found that sample frequency can affect comparison choice when delays are introduced independently of the number of choices of each of the comparison stimuli in training and the number of reinforcements associated with each of the comparison stimuli is equated. In the present experiment we found that the probability of choosing each of the comparison stimuli in training can affect comparison choice when delays are introduced, independently of sample frequency and when the number of reinforcements associated with each of the comparison stimuli is equated. Together, these experiments suggest that when the sample is not available, there is a partial dissociation between comparison choice and the probability of reinforcement associated with each of the comparison stimuli.     

Human temperament and choice preference between probability of the goal achievement and the goal value

The purpose of this work was to experimentally ascertain the relationships between human formal-dynamic properties (temperament) and characteristics of his/her motivation sphere associated with the choice of a profession. Thirty eight students of a sports institute (aged 19-28) took part in the study. The formal-dynamic properties were assessed with the help of Rusalov's Questionnaire. The motivation of the choice of profession was assessed with the help of the specially developed test questionnaire. Two main components of choice motivation were identified: the value of the profession and probability of mastering this profession. It was found that persons of sanguine temperament (with a higher capacity for work, mobile and quick) are oriented primarily to the value of profession, while persons of melancholic temperament to the probability of mastering this profession.     

The choice of reinforcement quality depending on the delay time of the instrumental reaction in cats]

In experiments on seven cats instrumental delayed reflexes with different quality reinforcement were elaborated by method of "active choice", where the time of delay of the motor reaction served as a signal of quality of the reinforcement. Five cats used a strategy with long delay high-quality reinforcement (meat), and two cats preferred short delay and low-quality reinforcement (bread-meat mixture). In special experiments with the change of alimentary motivation (24-hour alimentary deprivation and saturation of animals) it was established that the level of alimentary motivation within the studied limits did not change the strategy of behaviour preferred by the given animal. Individually varying ability to choice of reaction determining more valuable reinforcement it is possible to consider as an experimental analogue of the mechanisms of will. The question is discussed about the role of typological properties of cats in choice of behaviour strategy.     

Effects of different fuchsin analogs on the Feulgen reaction

The Feulgen reaction is used for cytophotometric quantitation of nuclear DNA. Schiff's reagents used in the Feulgen reaction usually are prepared from basic fuchsin, a variable mixture of four triaminotriphenylmethane analogs. The effect of the several fuchsin analogs on the quality of Schiff's staining of hydrolyzed DNA is not known. In this investigation Schiff's reagents prepared from relatively pure fuchsin analogs were used to determine whether different fuchsin analogs affect the absorbance of the Schiff's reagent-DNA complexes formed in solution. It has been determined that the complex formed by pararosaniline-Schiff's reagent and hydrolyzed DNA exhibits lower absorption than do corresponding complexes formed by Schiff's reagents prepared from magenta II or from new fuchsin.     

Effects of free-food deliveries and delays on choice under concurrent-chains schedules

Pigeons responded on a concurrent-chains schedule with two equal variable-interval (VI) schedules as initial links and delays to food of 3 and 12s as the two terminal links. In even-numbered sessions, no other reinforcement schedule was present, and all pigeons showed a strong preference for the response key that had the shorter, 3-s terminal-link delay. In odd-numbered sessions, the initial links were interrupted at random times by one of three different types of events. When the interruptions were immediate food deliveries, the response percentages increased on the key that had the 3-s delay. When the interruptions were 30-s delays followed by food, the response percentages remained approximately unchanged. When the interruptions were 30-s delays with no food, the response percentages decreased. The results were used to compare the predictions of different mathematical models of concurrent-chains performance. The results favored models that assume that preference is determined by the relative amount of advantage that is gained when a terminal link is entered.     

Effects of different heparins on the enhancement of the thrombin-antithrombin reaction

Kinetic analyses were made of the thrombin/antithrombin III (ATIII) reaction in the presence of catalytic amounts of three kinds of mammalian HA-heparin (bovine, pig and whale), which have the same affinities for ATIII. In the absence of NaCl, the first-order rate constant was higher with whale HA-heparin than with the other two HA-heparins. However, the strength of the interactions of thrombin with the HA-heparins was in the order, bovine greater than pig greater than whale. Thus, the slow reactions in the case of bovine and pig HA-heparins were probably due to preferential binding of the two HA-heparins to thrombin rather than to ATIII, thus causing the HA-heparins to be inhibitory for the reaction by reducing the turnover rates of the polysaccharides as catalysts. In the presence of 0.15M NaCl, the first-order rate constants were slightly higher in the case of pig HA-heparin than of the other two HA-heparins. Since the strength of the interactions of these HA-heparins with thrombin was in the order, pig greater than or equal to bovine greater than whale, the faster reactions were probably due to higher associations of the enzyme with the essential HA-heparin-ATIII complex.     

Effects of different feeder layers on short-term culture of prepubertal bovine testicular germ cells in-vitro

Spermatogonial stem cells (SSCs) are exceptional adult stem cells that transfer genes to new generations. This behavior makes them unique cells for the production of transgenic farm animals. However, this goal has been hampered by their spontaneous differentiation during in vitro culture. Therefore, the objective of this study was the evaluation of the effects of different feeders on in vitro short-term culture of prepubertal bovine testicular germ cells. The isolated cell suspensions containing SSCs were enriched by Bovine serum albumin (BSA) and gelatin and were cultured in the presence of Glial-derived neurotrophic factor (GDNF), Epidermal Growth Factor (EGF) and basic Fibroblastic Growth Factor (bFGF). After 7 d of culture, colonies were harvested and cultured on four different feeders, including SIM mouse embryo-derived thioguanine and ouabain resistant (STO), mouse embryonic fibroblast, bovine Sertoli cells (BSC) and on a laminin-coated plate. The number and area of colonies were measured at seven, 11 and 14 d post-culture. The expression of germ cells markers was detected using immunofluorescence and flow cytometry analyses on day 7, and quantitative real-time PCR at 14 d post-culture. Immunocytochemical staining revealed that colonies were positive for Dolichos biflorus agglutinin (DBA), Thy-1, Oct-4, c-ret, α6-integrin, β1-integrin and negative for c-kit. In addition, the number and area of those colonies formed on the STO feeder were significantly greater than the other groups. Relative expressions of Thy-1 in the STO and in BSC groups were significantly higher than other groups but expression of Oct-4 was highest in the laminin group compared to other groups. In conclusion, STO might be a suitable feeder layer for in vitro propagation of bovine testicular germ cells.     

Effects of different feeder layers on culture of bovine embryonic stem cell-like cells in vitro

To find a suitable feeder layer is important for successful culture conditions of bovine embryonic stem cell-like cells. In this study, expression of pluripotency-related genes OCT4, SOX2 and NANOG in bovine embryonic stem cell-like cells on mouse embryonic fibroblast feeder layers at 1–5 passages were monitored in order to identify the possible reason that bovine embryonic stem cell-like cells could not continue growth and passage. Here, we developed two novel feeder layers, mixed embryonic fibroblast feeder layers of mouse and bovine embryonic fibroblast at different ratios and sources including mouse fibroblast cell lines. The bovine embryonic stem cell-like cells generated in our study displayed typical stem cell morphology and expressed specific markers such as OCT4, stage-specific embryonic antigen 1 and 4, alkaline phosphatase, SOX2, and NANOG mRNA levels. When feeder layers and cell growth factors were removed, the bovine embryonic stem cell-like cells formed embryoid bodies in a suspension culture. Furthermore, we compared the expression of the pluripotent markers during bovine embryonic stem cell-like cell in culture on mixed embryonic fibroblast feeder layers, including mouse fibroblast cell lines feeder layers and mouse embryonic fibroblast feeder layers by real-time quantitative polymerase chain reaction. Results suggested that mixed embryonic fibroblast and sources including mouse fibroblast cell lines feeder layers were more suitable for long-term culture and growth of bovine embryonic stem cell-like cells than mouse embryonic fibroblast feeder layers. The findings may provide useful experimental data for the establishment of an appropriate culture system for bovine embryonic stem cell lines.     

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).     

The model of the reward choice basing on the theory of reinforcement learning

We developed the model of alimentary instrumental conditioned bar-pressing reflex for cats making a choice between either immediate small reinforcement ("impulsive behavior") or delayed more valuable reinforcement ("self-control behavior"). Our model is based on the reinforcement learning theory. We emulated dopamine contribution by discount coefficient of this theory (a subjective decrease in the value of a delayed reinforcement). The results of computer simulation showed that "cats" with large discount coefficient demonstrated "self-control behavior"; small discount coefficient was associated with "impulsive behavior". This data are in agreement with the experimental data indicating that the impulsive behavior is due to a decreased amount of dopamine in striatum.     

Flower choice in honeybees: Effects of food value and flower density

To test the effects of food value on the flower choice, individual honeybees (Apis mellifera) were offered a choice of 25 % sucrose solution (SS) and 1 of 6 different SSs, ranging from 5 % to 50 % SS, at either a low or a high flower density. Artificial flowers were filled with each SS. The honeybees showed a stronger preference for a concentrated SS to a diluted SS at a high than at a low flower density, and the degree of preference was positively correlated to the difference in the sucrose concentration between paired SSs. These foraging patterns were consistent with qualitative predictions from optimal foraging theory. Furthermore, it was found that experience in feeding on a concentrated SS lowered the foraging motivation for a diluted SS at the high flower density, but not at the low flower density. I discuss the effects of food density, food profitability and experience on the foraging behaviour of honeybees.     

共振呼吸反馈训练对运动员心率变异性和选择反应时的影响

目的:探讨共振呼吸调节对运动员认知任务表现的提升作用。方法:将30名射击运动员随机分为试验组(n=15)和对照组(n=15)。试验组运动员进行每次30～40 min、每周5 d,共计4周的心率变异性生物反馈训练(HRV训练),掌握共振呼吸调节方法,以相同频次进行呼吸调节(每分钟6次);试验采用试验组、对照组前后测的设计,利用第三版神经行为测试评价系统(NES-C3)、生理相干和自主平衡系统SPCS采集运动员的选择反应时和心率变异性(HRV)数据;正式检测,首先让所有运动员经历安静阶段并进行选择反应时测试,随后试验组运动员进行共振呼吸调节,而对照组运动员休息,最后所有运动员再次进行选择反应时测试,测量运动员的心率变异性。结果:与安静阶段相比,试验组运动员心率(HR)显著下降(P<0.05),心脏总功率(TP)和低频功率(LF)与安静阶段相比显著增加(P<0.01),低频/高频功率(LF/HF)也显著增加(P<0.05),自我调节后的选择反应时显著降低(P<0.05);而对照组无显著变化(P>0.05)。结论:共振呼吸调节法可以显著增强运动员的心率变异性水平,...