Abstract: The two sides of the brain may be differently involved in the modulation of immune responses as demonstrated by lesional and behavioral approaches in rodents. Lesions of right or left neocortex induced opposite effects on various immune parameters including mitogen-induced lymphoproliferation, interleukin-2 production, macrophage activation or natural killer cell activity. This animal model, useful to elucidate whereby the brain and the immune system can communicate, appears to be suitable for studying the immune perturbations observed during stroke in humans. Brain asymmetry in modulation of immune reactivity may also be demonstrated in intact animal using a behavioral paradigm. The direction of a lateralized motor behavior ie paw preference in a food reaching task, correlated with an asymmetrical brain organization, was shown to be associated with lymphocyte reactivity, natural killer cell activity and auto-antibody production. The association between paw preference and immune reactivity in mice varies according to the immune parameters tested and is a sex-dependent phenomenon in which genetic background may be involved. The experimental models for investigating asymmetrical brain modulation of the immune system should be useful for studying several physiological, pathological and genetic aspects of neuroimmunomodulation.

Abstract: Bringing the head and neck of ridden horses into a position of hyperflexion is widely used in equestrian sports. In our study, the hypothesis was tested that hyperflexion is an acute stressor for horses. Salivary cortisol concentrations, heart rate, heart rate variability (HRV) and superficial body temperature were determined in horses (n = 16) lunged on two subsequent days. The head and neck of the horse was fixed with side reins in a position allowing forward extension on day A and fixed in hyperflexion on day B. The order of treatments alternated between horses. In response to lunging, cortisol concentration increased (day A from 0.73 ± 0.06 to 1.41 ± 0.13 ng/ml, p < 0.001; day B from 0.68 ± 0.07 to 1.38 ± 0.13 ng/ml, p < 0.001) but did not differ between days A and B. Beat-to-beat (RR) interval decreased in response to lunging on both days. HRV variables standard deviation of RR interval (SDRR) and RMSSD (root mean square of successive RR differences) decreased (p < 0.001) but did not differ between days. In the cranial region of the neck, the difference between maximum and minimum temperature was increased in hyperflexion (p < 0.01). In conclusion, physiological parameters do not indicate an acute stress response to hyperflexion of the head alone in horses lunged at moderate speed and not touched with the whip. However, if hyperflexion is combined with active intervention of a rider, a stressful experience for the horse cannot be excluded.

Abstract: In most experimental work on animal cognition, researchers attempt to control for multiple interacting variables by training subjects prior to testing, allowing subjects to participate voluntarily, and providing subjects with food rewards. However, do such methods encourage selection bias from subjects’ personalities? In this study, we trained eighteen zoo-housed capuchin monkeys (Sapajus apella) for two experiments, under conditions of positive reinforcement (i.e. food rewards) and free-choice participation. Using a combination of behavioral and rater-based methods, we identified and validated five personality dimensions in these capuchins (Assertiveness, Openness, Neuroticism, Sociability, and Attentiveness). Scores on Openness were positively related to individual differences in monkey task participation, reflecting previous work showing that such individuals are often more active, curious, and willing to engage in testing. We also found a negative relationship between scores on Assertiveness and performance on tasks, which may reflect the trade-offs between speed and accuracy in these animals’ decision-making. Highly Assertive individuals (the most sociable within monkey groups) may also prioritize social interactions over engaging in research. Lastly, monkeys that consistently participated and performed well on both tasks showed significantly higher Openness and lower Assertiveness compared to others, mirroring relationships found between personality, participation, and performance among all participants. Participation and performance during training was clearly biased toward individuals with particular personalities (i.e. high Openness, low Assertiveness). Results are discussed in light of the need for careful interpretation of comparative data on animal cognition and the need for researchers to take personality selection bias more seriously.
Animal Cognition Animal Cognition Look
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Abstract: This article traces the history of scientific and empirical interval training. Scientific research has shed some light on the choice of intensity, work duration and rest periods in so-called 'interval training'. Interval training involves repeated short to long bouts of rather high intensity exercise (equal or superior to maximal lactate steady-state velocity) interspersed with recovery periods (light exercise or rest). Interval training was first described by Reindell and Roskamm and was popularised in the 1950s by the Olympic champion, Emil Zatopek. Since then middle- and long- distance runners have used this technique to train at velocities close to their own specific competition velocity. In fact, trainers have used specific velocities from 800 to 5000m to calibrate interval training without taking into account physiological markers. However, outside of the competition season it seems better to refer to the velocities associated with particular physiological responses in the range from maximal lactate steady state to the absolute maximal velocity. The range of velocities used in a race must be taken into consideration, since even world records are not run at a constant pace. Copyright 2001 Adis International

Abstract: Horses are one-sided, not only on a motor level, but they also prefer to use one eye, ear or nostril over the other under particular circumstances. Horses usually prefer using the left eye to observe novel objects and humans. This preference is more marked in emotional situations and when confronted with unknown persons. Thus the horse’s visual laterality provides a good option for assessing its mental state during training or in human-horse interactions. A strong preference for the left eye may signal that a horse cannot deal with certain training situations or is emotionally affected by a particular person.
Pferde benutzen für die Begutachtung von Objekten und Menschen bevorzugt eine bestimmte Nüster, ein Ohr oder ein Auge. So betrachten die meisten Pferde Objekte und Menschen mit dem linken Auge. Die Lateralitätsforschung erklärt diese sensorische Lateralität mit der Verarbeitung von Informationen unterschiedlicher Qualität in verschiedenen Gehirnhälften und zeigt auf, dass positive und negative emotionale Informationen sowie soziale Sachverhalte mit dem linken Auge aufgenommen und vorwiegend an die rechte Gehirnhälfte weitergegeben werden. In diesem Zusammenhang ermöglicht die visuelle Lateralität, den Gemütszustand des Pferdes im Training und im therapeutischen Fördereinsatz zu erkennen und zu berücksichtigen.