negative stimulus
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Learning allows animals to respond to changes in their environment within their lifespan. However, many responses to the environment are innate, and need not be learned. Depending on the level of cognitive flexibility an animal shows, such responses can either be modified by learning or not. Many ants deposit pheromone trails to resources, and innately follow such trails. Here, we investigated cognitive flexibility in the ant Lasius niger by asking whether ants can overcome their innate tendency and learn to avoid conspecific pheromone trails when these predict a negative stimulus. Ants were allowed to repeatedly visit a Y-maze, one arm of which was marked with a strong but realistic pheromone trail and led to a punishment (electroshock and/or quinine solution), and the other arm of which was unmarked and led to a 1 M sucrose reward. After circa 10 trials ants stopped relying on the pheromone trail, but even after 25 exposures they failed to improve beyond chance levels. However, the ants did not choose randomly: rather, most ants begun to favour just one side of the Y-maze, a strategy which resulted in more efficient food retrieval over time, when compared to the first visits. Even when trained in a go/no-go paradigm which precludes side bias development, ants failed to learn to avoid a pheromone trail. These results show rapid learning flexibility towards an innate social signal, but also demonstrate a rarely seen hard limit to this flexibility.

In order to be successful and have high standards of animal welfare, modern zoos strive to regularly modify, improve, and build animal enclosures and visitor areas. However, these periods of development could result in temporary durations of sub-optimal welfare for animals housed nearby. In this study, we monitored the behavior of three Asiatic lions (Panthera leo persica) prior to, during, and following a period of construction on a nearby building. Our results provide evidence that welfare may have been temporarily reduced during the construction period. Compared to the pre-construction period, the male exhibited an increase in pacing behavior and all three lions reduced the time they spent resting. We infer that the most significant negative stimulus related to the construction was sound and/or ground vibrations, as a physical barrier ruled out stress from visual stimuli. The behavioral response to the construction work was relatively short-lived and no long-term changes were observed one year on. This research highlights the importance of measuring animal behavior around events outside routine husbandry, and considering animal welfare on an individual basis. Finally, this work adds to the body of literature surrounding the impacts of construction on animal wellbeing and outlines some suggestions for potential mitigation.

Despite dogs’ widespread use as detection systems, little is known about how dogs generalize to variations of an odorant’s concentration. Further, it is unclear whether dogs can be trained to discriminate between similar concentration variations of an odorant. Four dogs were trained to an odorant (0.01 air dilution of isoamyl acetate) in an air-dilution olfactometer, and we assessed spontaneous generalization to a range of concentrations lower than the training stimulus (Generalization Test 1). Dogs generalized to odors within a 10-fold range of the training odorant. Next, we conducted discrimination training to suppress responses to concentrations lower than a concentration dogs showed initial responding towards in Generalization Test 1 (0.0025 air dilution). Dogs successfully discriminated between 0.0025 and 0.01, exceeding 90% accuracy. However, when a second generalization test was conducted (Generalization Test 2), responding at the 0.0025 concentration immediately recovered and was no different than in Generalization Test 1. Dogs were then tested in another generalization test (Compound Discrimination and Generalization) in which generalization probes were embedded within discrimination trials, and dogs showed suppression of responding to the 0.0025 concentration and lower concentrations in this preparation. These data suggest dogs show limited spontaneous generalization across odor concentration and that dogs can be trained to discriminate between similar concentrations of the same odorant. Stimulus control, however, may depend on the negative stimulus, suggesting olfactory concentration generalization may depend on relative stimulus control. These results highlight the importance of considering odor concentration as a dimension for generalization in canine olfactory research.

Alzheimer’s disease (AD) is a long-lasting progressive neurodegenerative disease that degrades memory and cognitive function and is often complicated by disorientation and other psychiatric syndromes. At present, to improve the condition of patients with AD, for their treatment, use the drug memantine. The drug is a noncompetitive antagonist of NMDA glutamate receptors in the brain. The present experiments aimed to test the influence of memantine on the memory processes in rats. We used the passive avoidance test “Stepdown”. The latter is used to assess memory function based on the association formed between a particular environment that an animal is learning to avoid and a negative stimulus in the form of a weak electric shock to the feet. We found that memantine significantly, twice, decreased the latency time step-down from the platform in rats during their familiarization with the chamber. The rats became more determined and less afraid of the unknown environment under memantine. Memantine significantly affected the emotionality of young rats, which leads to errors in the passive avoidance test. However, it did not impair memory. It can be concluded that memantine induces a shift toward greater excitability in rats.

362 patients with cognitive impairment in depressive disorders were examined: 123 patients with recurrent depressive disorder (RDD), 141 patients with bipolar affective disorder (BAD) and 98 patients with prolonged depressive reaction (PDR). A set of research methods was used: clinical-psychopathological, psychodiagnostic (Munsterberg test) and statistical. The features of the perception process were established for various types of depressive disorders: in patients with RDD, there was a predominance of average, increased and decreased selectivity of attention to neutral stimulus (30.89 %, 21.95 % and 21.95 %, respectively), high selectivity of attention to negative stimulus (33.33 %) and decreased and low selectivity of attention to positive stimulus (54.47 % and 20.33 %, respectively); in patients with BAD, a predominance of average and reduced selectivity of attention to neutral stimulus (45.39 % and 36.17 %, respectively) and average selectivity of attention to negative and positive stimulus (38.30 % and 38.30 %, respectively) were recorded; in patients with PDR, the prevalence of average and reduced selectivity of attention to neutral stimulus (42.86 % and 34.69 %, respectively), increased and decreased selectivity of attention to negative stimulus (29.59 % and 16.33 %, respectively), increased selectivity of attention to positive stimulus (43.88 %). Key words: patients with cognitive impairment, depressive disorders, perception process, recurrent depressive disorder, bipolar depressive disorder, prolonged depressive reaction

There is considerable interest in Cognitive Bias Modification (CBM) as a potential treatment for overweight / obesity. Inhibitory Control Training (ICT) and Evaluative Conditioning (EC) are two popular paradigms which rely on associatively learned responses (unhealthy food -> inhibition, or unhealthy food-> negative stimulus, respectively) through repeated cue-response contingencies. Both ICT and EC have demonstrated some effectiveness for reducing food intake, value and / or choice, when administered in the laboratory and online. However, studies have been criticised for inconsistencies in design (e.g. use of inadequate control groups) which makes it difficult to draw robust conclusions. In two pre-registered, online studies our aim was to examine active ICT (study 1) and EC (study 2) in multiple groups where the cue->response contingencies were systematically varied (100%, 75%, 50%, 25%), before examining food-cue valuations and hypothetical food choice. In both studies varying the cue-> response contingencies did not lead to significant changes in food-cue devaluation following training. ICT did not substantially influence hypothetical food choice, whereas there was weak evidence that EC reduced choice for unhealthy foods, compared to a control group with 50% cue-response contingencies. Taken together both studies provide limited evidence for online CBM as a viable psychological treatment – at least through the mechanism of food-cue devaluation or changes in healthy and unhealthy food choice. Future research is needed to investigate the factors that contribute towards successful CBM training to critically evaluate the potential for these strategies within health interventions.

The present article deals with maintenance and features of the using of ecological financial and credit instruments which predetermine to the incipience of the ecological economy in the world and in Ukraine. We’ve found its influence to reduction of emissions of greenhouse gases and development of renewable energy sources. It was analyzed socio-economic problems of financing events for the establishment of the "green" economy in the countries of the world. The ways of decision of these problems by using “green” finance and their elements such as climatic finances, climatic positive and negative stimulus, carbon tax, "green" bonds, "green" tariff, "green" certificate etс are offered in this article. We have investigated socio-economic preconditions of receiving financial support from the Green Climate Fund and other international financial organizations to individual Ukrainian enterprises, territorial communities and households in modern terms. We educed the problems of application of "green" tariff in the countries of the world and in Ukraine and explained ways of decision these problems.  

The rapid development of Artificial Intelligence (AI) in recent years has greatly improved humans’ quality of life and promoted Information Systems (IS) development progress. Business Intelligence (BI) system is one of the tools in the field of IS which obtained benefits from the development of AI. The adoption of BI can enhance the competitive aspect of a business organization in today’s highly competitive business environment and play an important role in determining a business organization’s success. However, literature shows that the adoption rate of the BI system is low and it is predicted that the adoption rate will not increase a lot in near future. Prior research studies paid less attention in a comprehensive study that review research articles related to BI system adoption in regard to discuss the issues and research gaps. There is an absence of a clear agenda or roadmap in the research area of BI adoption. Therefore, this study aims to synthesize and analyze research studies of BI adoption in the past two decades, identify the major theories that researchers have used to predict the adoption of BI, and summarize key antecedents that influence the adoption of BI. This study reviewed 44 research articles published on the adoption of BI between the year 2000 and the first quarter of 2020. The findings first indicate that the analysis of BI adoption literature is not comprehensive enough. Researchers in the past two decades commonly rely on TAM and its modifications to measure the adoption of BI. The finding also indicates that there are limited research studies on the negative stimulus of BI adoption. This study proposes the agenda for continued research in the area of BI adoption that targets identified gaps in the literature.

Previous behavioral studies using stimulus-response compatibility tasks have shown that people are faster to carry out instructed approach/avoidance responses to positive/negative stimuli. This result has been taken as evidence that positive/negative stimulus valence directly activates a tendency to approach/avoid, which in turn, facilitates execution of instructed approach/avoidance behavior. In these studies, however, it cannot be excluded that the results reflect a purely semantic link between stimulus valence and instructed responses. According to this alternative interpretation, positive/negative stimuli do not elicit an approach/avoidance tendency, but instead they interact with the positive/negative valence of the instructed responses, and in this way, produce the observed compatibility effect. To circumvent this possible disadvantage of compatibility tasks, we used a novel method for the measurement of early action tendencies: TMS induced MEPs. In two experiments, participants were first trained to abduct the index finger to approach and the thumb to avoid. Then, they observed a series of positive and negative stimuli. Each stimulus was followed by a TMS pulse (at 400 ms post-stimulus onset) and MEPs were measured continuously on the muscles of both fingers. These observation trials were randomly intermixed with response trials, in which neutral stimuli were presented and participants were instructed to approach/avoid the stimuli. In Experiment 1, participants received clear visual feedback on the outcome of their response in the response trials. In Experiment 2, we omitted this feedback to test whether it was necessary for the effect to occur. The results indicated higher MEPs for the approach/avoidance finger after positive/negative stimuli in Experiment 1 but not in Experiment 2. Analyses on the data aggregated over both experiments suggest that the visual feedback was necessary for stimulus valence to elicit action tendencies. Taken together, the results are in line with the results of behavioral studies with compatibility tasks, suggesting that stimulus valence directly elicits specific action tendencies already at 400 ms but they indicate that clear visual feedback is necessary for this effect to occur.