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This paper presents a closed-form cooperative avoidance control design for 3-dimensional rigid-body agents. New avoidance functions are designed to integrate the collision risk with the addition of motion and posture information. Time-varying sensing regions enable the conflict resolution actions only when there is a potential risk of collision, thus further reducing some unnecessary interference with other objectives. These characteristics lead to the less-conservative avoidance response, smoother maneuvers, and milder motion trajectories. The stability of the proposed method is analyzed and the corresponding proofs and guaranties for collision-free maneuvering, are provided. Performance comparisons are presented for two simulation scenarios, which illustrate the effectiveness and reliability of the new method.

Owing to their predictability, tidal currents are an attractive source of renewable energy. However, data on the environmental impacts, especially at array scale, are lacking. We present a spatial analysis of telemetry data, identifying the effects of the presence and operations of the world's first commercial sized tidal turbine array on the movements of an acoustically sensitive marine mammal; the harbour seal (Phoca vitulina). No significant change in at sea distribution was detected between pre and post installation of the 4 turbine array. However, seals showed overt avoidance responses during turbine operations, with a significant decrease in predicted abundance (95% CIs: −11%, −49%) within ∼2 km of the array. These results provide important information for estimating collision rates between seals and tidal turbine arrays and demonstrate an analytical framework which can be used to assess the effect of arrays on other marine animal distributions. Collision risk models used to estimate collision rate between tidal turbines and marine mammals traditionally assume some non-empirical degree of avoidance, or no avoidance. The avoidance response elicited by seals to these devices could reduce the likelihood of direct collisions, with estimated avoidance rates measured here suggesting a decrease in total number of between 0.4% and 2% per annum. Further, given sustained barrier effects were not identified, avoidance may only be occurring during the potentially dangerous periods during operations thereby not restricting movement through the site at all times. However, future environmental impact assessments and spatial planning for array deployments should consider the potential for repulsion of acoustically sensitive top-predators away from ecologically important sites.

The present study evaluated the ability of Dichlorvos and Paraquat to provoke avoidance response in fingerlings of Nile tilapia Oreochromis niloticus and estimate the population immediate decline (PID). The non-forced multi-compartmented system used for non-forced assays, were constructed to allow free movement of fishes along six compartments. Fishes (n=3 per compartment/treatment, totaling 18 per system) were exposed to a gradient of Dichlorvos (1.0, 2.0, 4.0, 5.0 and 6.0 mg L-1) and Paraquat (10.0, 30.0, 50.0, 70.0, 100.0 mg L-1) and their distribution were recorded at 20 min interval for a 3-h period. Mortalities recorded in forced exposures were 17% and 0% at lowest concentrations and, 67% and 83% at highest concentrations for Dichlorvos and Paraquat correspondingly. For non-forced exposure, fishes presented a significant (p < 0.005) gradient-dependent spatial avoidance for both pesticides after 3-h. They avoided the lowest concentrations of Dichlorvos and Paraquat (1.0 and 10.0 mg L-1) by 40% and 90% respectively and 100% at the highest concentrations for both pesticides. The PID was driven by avoidance behavior rather than mortality. This result indicates that the dangers of pesticide contamination is not only in their toxicity to organisms, but also, in habitat selection processes by organism resulting in serious environmental turbulence.

Some wind farms have implemented automated camera-based monitoring systems, e.g., IdentiFlight to mitigate the impact of wind turbines on protected birds. These systems have promoted the collection of large amounts of unique data that can be used to describe flight behavior in a novel way. The aim of this study was to evaluate how this unique data can be used to create a robust quantitative behavioral analysis, that can be used to identify risk-prone flight behavior and avoidance behavior and thereby used to assess collision risk in the future. This was achieved through a case study at a wind farm on the Swedish island Gotland, where golden eagles (Aquila chrysaetos), white-tailed eagles (Haliaeetus albicilla), and red kites (Milvus milvus), were chosen as the bird species. These three species are generally rare breeds in Europe and have also been shown to be particularly vulnerable to collisions with wind turbines. The results demonstrate that data from the IdentiFlight system can be used to identify risk-prone flight behaviors, e.g., tortuous flight and foraging behavior. Moreover, it was found that these flight behaviors were affected by both weather conditions, but also their distance to the nearest wind turbine. This data can, thus, be used to evaluate collision risk and avoidance behavior. This study presents a promising framework for future research, demonstrating how data from camera-based monitoring systems can be utilized to quantitatively describe risk-prone behavior and thereby assess collision risk and avoidance behavior.

Excessive acid deposition causes soil acidification, and changes the soil microhabitat, thus affecting the survival and reproduction of soil organisms. Folsomia candida (Collembola, Isotomidae), as a model organism, is widely used to assess the chemical toxicity in soil, and its avoidance response can indicate the environmental changes. In this study, we used Folsomia candida to assess the risks of acid deposition on soil ecosystems. Different pH (3.0, 3.5, 4.0, 4.5, 5.0, and 5.5) treatments were set up in petri dish experiments, and the avoidance behavior of Folsomia candida was measured after 12, 24, and 48 h exposure to the pH conditions. The results indicated that (1) both the exposure duration and pH level influenced avoidance behavior of collembolan. (2) After 12 h exposure, most of the individuals showed avoidance behavior but without significant differences among the treatments. (3) After 24 h exposure, significant avoidance behavior was observed at pH 3.0, 3.5, and 4.0. (4) After 48 h exposure, avoidance behavior was found in all treatment conditions except for pH 5.5. This study clarified the direct responses of soil fauna to acid deposition, and indicated that both pH and length of exposure influenced the avoidance behavior of Folsomia candida. During the experimental period, the collembolan reacted negatively and showed consistent avoidance behavior at pH 3.0, 3.5, and 4.0. Reversed avoidance behavior was apparent between pH 4.5 and 5.0 and not observed at pH 5.5, indicating that the latter was the preferred pH environment.

Chemical cues can alert prey to the presence of predators before the predator is within visual proximity. Recognition of a predator’s scent is therefore an important component of predator awareness. We presented predator and control scents to wild, wild-born captive, and predator-naive captive-born pygmy bluetongue lizards to determine (1) whether lizards respond to reptile chemical cues differently from controls, (2) whether captive lizards respond more strongly to a known predator than to other predatory reptiles, (3) whether captive-born lizards recognise predators innately, whether captive-born lizards have reduced predator recognition compared with wild lizards and whether time spent in captivity reduces responses to predators, and (4) whether the avoidance response to predator detection differs between naive and experienced lizards. There was no significant difference in the number of tongue flicks to predator scent among wild, wild-born and captive-born lizards, suggesting that predator detection is innate in the pygmy bluetongue lizard and time in captivity did not reduce predator recognition. The number of tongue flicks directed towards brown snake scent was significantly higher than that to the novel and water controls for all lizard origins. Lizards of all origins continued to bask in the presence of predator scents, suggesting that chemical cues alone may be insufficient to instigate an avoidance response and other cues may be required.

Introduction: Patients with dementia show reduced adaptive, behavioral, and physiological responses to environmental threats. Physical exercise is expected to delay brain aging, maintain cognitive function and, consequently, help dementia patients face threats and protect themselves skillfully. Methods: To confirm this, we aimed to investigate the effects of the shaking exercise on the avoidance function in the senescence-accelerated mouse-prone strain-10 (SAMP-10) model at the behavioral and tissue levels. SAMP-10 mice were randomized into 2 groups: a control group and a shaking group. The avoidance response (latency) of the mice was evaluated using a passive avoidance task. The degree of amygdala and hippocampal aging was evaluated based on the brain morphology. Subsequently, the association between avoidance response and the degree of amygdala-hippocampal aging was evaluated. Results: Regarding the passive avoidance task, the shaking group showed a longer latency period than the control group (p < 0.05), even and low intensity staining of ubiquitinated protein, and had a higher number of and larger neurons than those of the control group. The difference between the groups was more significant in the BA region of the amygdala and the CA1 region of the hippocampus (staining degree: p < 0.05, neuron size: p < 0.01, neuron counts: p < 0.01) than in other regions. Conclusions: The shaking exercise prevents nonfunctional protein (NFP) accumulation, neuron atrophy, and neuron loss; delays the aging of the amygdala and hippocampus; and maintains the function of the amygdala-hippocampal circuit. It thus enhances emotional processing and cognition functions, the memory of threats, the skillful confrontation of threats, and proper self-protection from danger.

Background Behaviour of potential host fish during chemical treatment against the ectoparasite Gyrodactylus salaris is a vital factor in designing treatment strategies, evaluating risk factors and establishing insights into previously failed treatments. The effectiveness of any chemical treatment may be compromised if fish either are forced to, or seek out actively, areas of the river where the water quality is less affected by the chemicals. The aim of this study was to develop and apply an acoustic fish tag for fish localization with sensors for in situ measurement of water conductivity and temperature to investigate fish behaviour before, during and after an aluminium (Al) treatment. The sensor tag allowed discrimination between water qualities, and thereby quantification of exposure to treatment water. Findings Adult Atlantic salmon and anadromous brown trout from river Lærdalselva were tagged with external conductivity transmitters and followed daily by a network of passive receivers and by manual tracking 1 week ahead of treatment, during a 2-week aluminium (Al) treatment period and one week after an Al treatment. The results show no avoidance behaviour related to the Al treatment and most of the fish exhibited a behaviour during the treatment that did not differ significantly from the behaviour observed before or after the treatment. Data collected from the tags showed that the fish experienced increased conductivity during Al administration, suggesting successful exposure to treatment water. The tag gave verifiable environmental information and functioned well in the turbulent and acoustically demanding river environment, albeit with variable detection range. Conclusions The conductivity and temperature tag provided novel data on fish behaviour and exposure during the Al treatment period. Results show that fish exhibit normal behaviour during this period and no avoidance response can be detected in the collected data.

The sporangiophores of Phycomyces blakesleeanus have been used as a model system to study sensory transduction, helical growth, and to establish global biophysical equations for expansive growth of walled cells. More recently, local statistical biophysical models of the cell wall are being constructed to better understand the molecular underpinnings of helical growth and its behavior during the many growth responses of the sporangiophores to sensory stimuli. Previous experimental and theoretical findings guide the development of these local models. Future development requires an investigation of explicit and implicit assumptions made in the prior research. Here, experiments are conducted to test three assumptions made in prior research, that (a) elongation rate, (b) rotation rate, and (c) helical growth steepness, R, of the sporangiophore remain constant during the phototropic response (bending toward unilateral light) and the avoidance response (bending away from solid barriers). The experimental results reveal that all three assumptions are incorrect for the phototropic response and probably incorrect for the avoidance response but the results are less conclusive. Generally, the experimental results indicate that the elongation and rotation rates increase during these responses, as does R, indicating that the helical growth steepness become flatter. The implications of these findings on prior research, the “fibril reorientation and slippage” hypothesis, global biophysical equations, and local statistical biophysical models are discussed.

There has been little information about the role of histamine on the central nervous system (CNS), different from dopamine and serotonin. In the present study, therefore, the effects of histamine and related compounds on the CNS were studied using rats. Intracerebroventricular (i.c.v.) injection of histamine and 2-methylhistamine ameliorated memory deficit after long interrution of learning in active avoidance response. First generation H1-antagonists inhibited active avoidance response, whereas newly develpoed H1-antagonists showed little effect. α-Fluoromethylhistidine, an histidine decarboxylase inhibitor, also inhibited active avoidance response. In radial maze performance, almost the same findings were obtained. I.c.v. injection of histamine and H1-agonists inhibited amygdaloid kindled seizures. First generation H1-antagonists attenuated histamine-induced inhibition of amygdaloid kindled seizures. Both i.c.v. and intraperitoneal injections of H3-antagonist, thioperamide, resulted in a dose-related inhibition of amygdaloid kindled seizures. The effect of thioperamide was inhibited by an H3-agonists and H1-antagonists. Similar to nitrazepam, diphenhydramine and chlorpheniramine caused a shortening of sleep latency. On the other hand, no significant effects were observed with second generation H1-antagonists. These findings suggest that histamine plays an important role in learning and memory via H1-receptors, an inhibition of amygdaloid kindled seizures induced by histamine occurred through not only H1-receptors but also H3-receptors, and that classic H1-antagonists can be useful as a effective hypnotic for difficulty in falling asleep.

This research aimed to confirm the predator avoidance behavior of mice from snake droppings as a stimulant. Snake droppings are obtained from snakes fed with mice that come from the same strain as the mice being tested for response. Snake droppings were diluted into three different concentrations (25%, 50%, and 75%). The results showed that male individuals tend to avoid the odor stimuli than the female, it’s shown by the higher avoidance duration in males than the females. The results also indicate that innate behavior takes role in the avoidance response since the mice have never been exposed to any presence of predator.

Trait or stimulus valence related differences in heart rate change have often been investigated in psychophysiological research. However, the influence of different behavioral responses during motivational contexts on cardiac response patterns has been neglected so far. In this manuscript, HR change during movement via joystick during the negatively valent motivational condition of a virtual T-maze was investigated in two studies. Concerning the behavior, two specific avoidance response types could be identified in previous studies: a backwards withdrawal and an approach to safety. HR change and skin conductance response were hypothesized to be differentially related to these response patterns. For HR changes, the proposed difference was found. Participants facing the safety zone during their avoidance showed cardiac responses associated with the defensive response. In contrast, participants facing the negative entity of the virtual T-maze during their backwards withdrawal yielded cardiac responses associated with orienting reactions. Interestingly, these differences were found independently of the stimuli used in the two paradigms (monster vs. man). These findings lead to the conclusion that the execution of different behavioral responses during motivational conditions is an important factor in analyzing psychophysiological patterns, because they change according to the executed behavior and the linked visual and motivational properties.

While interest in active avoidance has recently been resurgent, many concerns relating to the nature of this form of learning remain unresolved. By separating stimulus and response acquisition, aversive Pavlovian-instrumental transfer can be used to measure the effect of avoidance learning on threat processing with more control than typical avoidance procedures. However, the motivational substrates that contribute to the aversive transfer effect have not been thoroughly examined. In three studies using rodents, the impact of a variety of aversive signals on shock-avoidance responding (i.e., two-way shuttling) was evaluated. Fox urine, as well as a tone paired with the delivery of the predator odor were insufficient modulatory stimuli for the avoidance response. Similarly, a signal for the absence of food did not generate appropriate aversive motivation to enhance shuttling. Only conditioned Pavlovian stimuli that had been paired with unconditioned threats were capable of augmenting shock-avoidance responding. This was true whether the signaled outcome was the same (e.g., shock) or different (e.g., klaxon) from the avoidance outcome (i.e., shock). These findings help to characterize the aversive transfer effect and provide a more thorough analysis of its generalization to warning signals for different kinds of threats. This feature of aversive motivation has not been demonstrated using conventional avoidance procedures and could be potentially useful for applying avoidance in treatment settings.

The aim of this study was to evaluate fear condition responses in sheep and goat and to relate this to the neuroarchitecture of their amygdala. Forty adult sheep (Uda breed) and 40 adult goats (Red Sokoto breed) were fear-conditioned by associating the sound of a car horn (neutral stimuli) with water spray (aversive stimuli) and the fear response was determined by direct observation of the behavior of the sheep and goats and measuring their flight distances and escape time. Eight groups were studied, each comprising of 10 animals (five sheep and five goats). Goats and sheep were tested alternately in the morning of every day of the week for three consecutive weeks, in which 4 days was used for habituation and 3 days for testing. Histologically, neurons in the central and basolateral complex of the amygdala were studied and analyzed using Nissl and golgi staines. Behaviorally, goats elicited an active avoidance response expressed as flight with concomitant intense flight distances (p < .001) compared to sheep. Although, sheep had larger brain parameters, it showed attenuated basolateral amygdala cytoarchitecture consistent with reduced fear perception and response. Goats had significantly more densely distributed pyramidal and spiny stellate neurons in the basolateral amygdala while sheep showed more non-pyramidal and aspiny neurons. These results provide interesting practical perspectives on how adaptions in the amygdala coincides with alterations in fear conditioning in domestic animals and may be the basis for the higher incidence of the sheep in automobile accidents than goats in developing countries especially Africa.

Dementia is a set of symptoms that include worsening of the routine of cognitive tasks, learning, reproducibility, and gait disturbances beyond typical aging. Activated c AMP can produce anti-apoptosis activity, neuroprotective activity, motor improvement, and cognitive enhancement activity. Cilostazol can increase c AMP levels, so this study aimed to evaluate the influence of cilostazol on learning-memory and motor coordination by rodent models. The rats were divided into 5 and 6 groups with 6 rats in each to test the hypothesis respectively. Before MES seizure induction the rats were trained for conditioned avoidance response for 14 days and the best one was selected for assessment. The performance of intervention treated groups to determine the memory retention effect was measured by applying a fixed number of shocks. The intervention treated groups were tested for motor coordination performance by rotarod test (4-45 RPM accelerating speed for 5 min) after 30 and 60 min. The latency time of each rat falls off from the rod for the first time was noted. The results were presented as Mean ± SD, tested by ordinary two way ANOVA followed by Tukey's multiple comparisons test. Cilostazol 100 mg/kg p.o demonstrated a significant memory enhancement activity in the conditioned avoidance response technique. Cilostazol 20mg/kg i.p alone and along with diazepam 2 mg/kg demonstrated a significant motor coordination performance in both sessions. The present study concludes that cilostazol has improved the learning & memory and motor coordination performances.

This paper is focused on the dynamics of the formation of conditioned responses in rats that experienced 14-day moderate magnetic shielding and were placed into a shelter setup when conducting the Barnes maze task. It was found that the acquisition rate of the conditioned active avoidance response was faster in rats under magnetic shielding conditions than that in the control animals. A direct accelerating effect of a moderate geomagnetic environment on the acquisition of the conditioned active avoidance response is thought to be extremely unlikely and the observed effect appears to be due to well-known biorhythm changes in pain sensitivity in hypomagnetic conditions associated with the development of hyperalgesia during the first week, which is an additional motivation for the formation of the conditioned active avoidance response in the Shelter setup. A two-phase change in pain sensitivity of male rats for a 14-day period was shown in the electrostimulation setup: hyperalgesia occurred during the first week and hypoalgesia was induced during the second week. The Barnes maze task did not reveal any differences between groups of control animals and experimental animals in recorded behavioral indices in hypomagnetic conditions within a 14-day period. Therefore, the accelerated formation of conditioned active avoidance response in rats under hypomagnetic conditions is most likely due to a significant increase in pain sensitivity during the first week of the experiment.

Caenorhabditis elegans secretes a complex cocktail of small chemicals collectively called ascaroside pheromones which serves as a chemical language for intra-species communication. Subsets of ascarosides have been shown to mediate a broad spectrum of C. elegans behavior and development, such as gender-specific attraction, repulsion, aggregation, olfactory plasticity, and dauer formation. Recent studies show that specific components of ascarosides elicit a rapid avoidance response that allows animals to avoid predators and escape from unfavorable conditions. Moreover, this avoidance behavior is modulated by external conditions, internal states, and previous experience, indicating that pheromone avoidance behavior is highly plastic. In this review, we describe molecular and circuit mechanisms underlying plasticity in pheromone avoidance behavior which pave a way to better understanding circuit mechanisms underlying behavioral plasticity in higher animals, including humans.

The human-assisted movement of species beyond their native range facilitates novel interactions between invaders and native species that can determine whether an introduced species becomes invasive and the nature of any consequences for native communities. Avoiding costly interactions through recognition and avoidance can be compromised by the naïvety of native species to novel invaders and vice versa. We tested this hypothesis using the common wall lizard, Podarcis muralis, and the native lizard species with which it may now interact in Britain (common lizard, Zootoca vivipara, sand lizard, Lacerta agilis) and on Vancouver Island (northern alligator lizard, Elgaria coerulea) by exploring species' responses (tongue flicks, avoidance behaviour) to heterospecific scent cues in controlled experiments. The tongue flick response of P. muralis depended on the different species’ scent, with significantly more tongue flicks directed to E. coerulea scent than the other species and the control. This recognition did not result in any other behavioural response in P. muralis (i.e. attraction, aggression, avoidance). Lacerta agilis showed a strong recognition response to P. muralis scent, with more tongue flicks occurring close to the treatment stimuli than the control and aggressive behaviour directed towards the scent source. Conversely, Z. vivipara spent less time near P. muralis scent cues than the control but its tongue flick rate was higher towards this scent in this reduced time, consistent with an avoidance response. There was no evidence of E. coerulea recognition of P. muralis scent in terms of tongue flicks or time spent near the stimuli, although the native species did show a preference for P. muralis-scented refuges. Our results suggest a variable response of native species to the scent of P. muralis, from an avoidance response by Z. vivipara that mirrors patterns of exclusion observed in the field to direct aggression observed in L. agilis and an ambiguous reaction from E. coerulea which may reflect a diminished response to a cue with a low associated cost. These results have significant implications for the invasive success and potential impacts of introduced P. muralis populations on native lizards.

En la evitación discriminada, una respuesta emitida durante la señal impide la aparición de un estímulo aversivo. La extinción de las respuestas de evitación se ha estudiado como la terminación de la relación instrumental entre la respuesta y el estímulo aversivo. Su compresión ha sido primordial para comprender el mantenimiento de la respuesta de evitación en humanos. Se compararon tres procedimientos de extinción de la respuesta de evitación en humanos. Veintisiete participantes, aprendieron una tarea de evitación discriminada dividida en dos fases: Pavloviana, con apareamientos de dos señales (Estímulo Condicionados; EC 1 y EC2) con un sonido (90 dB, 60 Hz), e Instrumental, donde la respuesta R1 ante el EC1 o la respuesta R2 ante el EC2 evitaba el sonido. Posterior a estas fases, fueron asignados a tres grupos, cada grupo experimentó diferentes procedimientos de extinción; (Estímulo Incondicionado, EI) donde R1 no termino con la señal, pero si con el sonido, (EC) donde R1 termino con la señal, pero no con el sonido, y (EC/EI) donde R1 no termino con ninguno de los estímulos (señal, sonido). En todos los grupos R2 continuó evitando el sonido. Los resultados mostraron que las respuestas de evitación R1 disminuyeron en los grupos EC y EC/EI, y no se extinguieron en el grupo EI. Estos resultados enfatizan la importancia de la terminación de la señal en el mantenimiento del aprendizaje de evitación discriminada.

The present study compared the direct and derived extinction of avoidance responses in equivalence classes. Two classes with four abstract figures in each class (Class 1: A1-B1-C1-D1; Class 2: A2-B2-C2-D2) were first established. An avoidance response that was trained in the presence of one stimulus (B1) was emitted under control of the other stimuli from the same class (C1 and D1). The subjects were then assigned to two different groups (Direct Extinction Group and Derived Extinction Group). Different extinction procedures were implemented for each group. In the Direct Extinction Group, B1 was presented in extinction. In the Derived Extinction Group, C1 was presented in extinction. Finally, the transfer of extinction was evaluated in the presence of the other stimuli from each class. In the Direct Extinction Group, avoidance responses were extinguished for 4 of the 16 participants in the presence of B1. In the Derived Extinction Group, avoidance responses were extinguished for 10 of the 16 participants in the presence of C1. The results indicated that derived extinction occurred more easily than direct extinction. Considering that avoidance responses were extinguished only for a few participants, future studies should implement more efficient procedures to establish avoidance extinction and then evaluate possible differences between derived and direct extinction in the transfer of extinction.

There has been a recent surge of interest in the development of the Judgement Bias Test (JBT) as a translational assay and objective measure of depressive interpretation bias. Judgement bias, namely the tendency of favoring an approach/avoidance response towards ambiguous cues, is thought to reflect a biased interpretation or anticipation of the cues. However, no study has examined the relationship between judgement bias and depressive interpretation bias. We validated the JBT against established measurements of interpretation bias in a college sample (Study 1) and an adolescent sample (Study 2). In both samples, a negative judgement bias was significantly associated with a depressive interpretation bias. However, the strength of the associations was only moderate and failed to meet the minimum qualification of convergent validity. Our results suggest that judgement bias and interpretation bias might be related but distinct. The JBT should not be used as an indirect assessment of interpretation bias in its current form, and it would be premature to claim that animal studies using the JBT could inform our understanding of cognitive biases in mood disorders. Nevertheless, the JBT might be useful for studying specific mechanisms, such as reward processing under ambiguity.

Los estudios de evasión espacial en sistemas multicompartimentado han demostrado la habilidad de algunos organismos para detectar la contaminación y huir hacia zonas menos contaminadas. Esta respuesta previene efectos adversos a nivel individual, aunque lleva a una pérdida local de especies, lo que podría provocar problemas a nivel ecosistémico. La evasión es estudiada mediante sistemas de ensayos con una exposición que simula un gradiente de contaminación y permite que los organismos elijan las zonas más favorables. Debido a que hay pocos estudios en comparación con las respuestas ecotoxicológicas tradicionales, es crucial saber cuán sensible es la respuesta de evasión frente a las demás respuestas ampliamente usadas. El presente trabajo se centró en comparar la sensibilidad de la evasión espacial con las respuestas ecotoxicológicas tradicionales mediante tres herramientas: representación del perfil de sensibilidad por grupos biológicos, creación de la distribución de las especies en función de la sensibilidad y finalmente calculándose la concentración de riesgo a 5% de las especies. El estudio ofrece una visión de la sensibilidad de la respuesta de evasión para especies de agua dulce y marinas como una señal del potencial riesgo asociado a la contaminación y discute la relevancia ecológica de dicha respuesta. Se ha observado que la evasión es una respuesta muy sensible al ser comparada con otras respuestas ecotoxicológicas y se constata la importancia de incluir dicha respuesta para evaluar los riesgos ecológicos de los contaminantes sobre la dispersión de los organismos. Palabras clave: evasión espacial; sistema multicompartimentado; exposición no forzada; cobre; HC5, SSD.

Aim Phosphodiesterase 10A (PDE10A) inhibitors not only have antipsychotic‐like effects but also cause cognitive enhancement without affecting extrapyramidal side effects in rodents, suggesting that PDE10A may be a novel approach for the treatment of schizophrenia. However, how a combination of PDE10A inhibitor with a currently available antipsychotic drug, risperidone contributes to the effect of each compound in rats remains unclear. The purpose of the present study was to examine the combination effects of MR1916 with a currently available antipsychotic drug, risperidone, in rats. Methods We examined the combination effects of the PDE10A inhibitor, MR1916 with risperidone on conditioned avoidance response (CAR) to assess antipsychotic‐like effects in rats. We also examined them on catalepsy as extrapyramidal side effects and novel object recognition test in cognitive functions in rats. Results MR1916 (0.025‐0.2 mg/kg, p.o.) and risperidone (0.75‐6 mg/kg, p.o.) alone attenuated the CAR in a dose‐dependent manner. The combination of MR1916 (0.025 mg/kg, p.o.) with risperidone (0.75 mg/kg, p.o.) significantly enhanced the attenuation of CAR without increasing the escape failure response. At the same dosage, the cataleptic effects were not enhanced by combined treatment of MR1916 with risperidone. Furthermore, the enhancement of object recognition memory induced by MR1916 (0.3 mg/kg, p.o.) was not affected by the combination with risperidone (0.75 mg/kg, p.o.). Conclusion The combination of MR1916 with risperidone may have additive antipsychotic‐like effects without affecting extrapyramidal side effects, and the cognitive‐enhancing effect of MR1916 may not be interfered with the addition of risperidone., We found that a novel PDE10A inhibitor, MR1916 with risperidone addtively enhanced the attenuation of conditioned avoidance response without increasing cataleptic effects. Additionaly, the enhancement in object recognition memory induced by MR1916 was not affected by the combination with risperidone.