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Licka, T., Kapaun, M., & Peham, C. (2004). Influence of rider on lameness in trotting horses. Equine Vet J, 36(8), 734–736.
Abstract: REASONS FOR PERFORMING STUDY: Equine lameness is commonly evaluated when the horse is being ridden, but the influence of the rider on the lameness has not been documented. OBJECTIVE: To document the effect of 2 riders of different training levels on the vertical movement of the head and croup. METHODS: Twenty mature horses were ridden at trot by an experienced dressage rider and a novice rider, as well as trotted in hand. Kinematic measurements of markers placed on the horse's head and sacral bone were carried out. The asymmetries of the vertical head and sacral bone motion were calculated as lameness parameters and compared with paired t tests. RESULTS: Trotting in hand, 17 horses showed forelimb lameness (1-4/10) and 13 hindlimb lameness (1-2/10). Intra-individually, 11 horses showed significant differences in forelimb lameness and 4 horses showed significant differences in hindlimb lameness when ridden. Over all horses, hindlimb lameness increased significantly under the dressage rider compared to unridden horses. CONCLUSIONS: The presence of a rider can alter the degree of lameness; however, its influence cannot be predicted for an individual horse. POTENTIAL RELEVANCE: In order to evaluate mild lameness, horses should be evaluated at trot both under saddle and in hand. If lameness is exacerbated, a second rider may be helpful; the level of training of the rider should be taken into consideration.
Keywords: Animals; Biomechanics; Body Weight; Exercise Test/veterinary; Female; Forelimb/physiopathology; Gait/*physiology; Head Movements/*physiology; Hindlimb/physiopathology; Horse Diseases/diagnosis/*physiopathology; Horses; Humans; Lameness, Animal/diagnosis/*physiopathology; Male; Stress, Mechanical; Weight-Bearing/physiology
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Fruehwirth, B., Peham, C., Scheidl, M., & Schobesberger, H. (2004). Evaluation of pressure distribution under an English saddle at walk, trot and canter. Equine Vet J, 36(8), 754–757.
Abstract: REASONS FOR PERFORMING STUDY: Basic information about the influence of a rider on the equine back is currently lacking. HYPOTHESIS: That pressure distribution under a saddle is different between the walk, trot and canter. METHODS: Twelve horses without clinical signs of back pain were ridden. At least 6 motion cycles at walk, trot and canter were measured kinematically. Using a saddle pad, the pressure distribution was recorded. The maximum overall force (MOF) and centre of pressure (COP) were calculated. The range of back movement was determined from a marker placed on the withers. RESULTS: MOF and COP showed a consistent time pattern in each gait. MOF was 12.1 +/- 1.2 and 243 +/- 4.6 N/kg at walk and trot, respectively, in the ridden horse. In the unridden horse MOF was 172.7 +/- 11.8 N (walk) and 302.4 +/- 33.9 N (trot). At ridden canter, MOF was 27.2 +/- 4.4 N/kg. The range of motion of the back of the ridden horse was significantly lower compared to the unridden, saddled horse. CONCLUSIONS AND POTENTIAL RELEVANCE: Analyses may help quantitative and objective evaluation of the interaction between rider and horse as mediated through the saddle. The information presented is therefore of importance to riders, saddlers and equine clinicians. With the technique used in this study, style, skill and training level of different riders can be quantified, which would give the opportunity to detect potentially harmful influences and create opportunities for improvement.
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Zhang, T. - Y., Parent, C., Weaver, I., & Meaney, M. J. (2004). Maternal programming of individual differences in defensive responses in the rat. Ann N Y Acad Sci, 1032, 85–103.
Abstract: This paper describes the results of a series of studies showing that variations in mother-pup interactions program the development of individual differences in behavioral and endocrine stress responses in the rat. These effects are associated with altered expression of genes in brain regions, such as the amygdala, hippocampus, and hypothalamus, that regulate the expression of stress responses. Studies from evolutionary biology suggest that such “maternal effects” are common and often associated with variations in the quality of the maternal environment. Together these findings suggest an epigenetic process whereby the experience of the mother alters the nature of the parent-offspring interactions and thus the phenotype of the offspring.
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Zhou, W. - X., Sornette, D., Hill, R. A., & Dunbar, R. I. M. (2005). Discrete hierarchical organization of social group sizes. Proc Biol Sci, 272(1561), 439–444.
Abstract: The 'social brain hypothesis' for the evolution of large brains in primates has led to evidence for the coevolution of neocortical size and social group sizes, suggesting that there is a cognitive constraint on group size that depends, in some way, on the volume of neural material available for processing and synthesizing information on social relationships. More recently, work on both human and non-human primates has suggested that social groups are often hierarchically structured. We combine data on human grouping patterns in a comprehensive and systematic study. Using fractal analysis, we identify, with high statistical confidence, a discrete hierarchy of group sizes with a preferred scaling ratio close to three: rather than a single or a continuous spectrum of group sizes, humans spontaneously form groups of preferred sizes organized in a geometrical series approximating 3-5, 9-15, 30-45, etc. Such discrete scale invariance could be related to that identified in signatures of herding behaviour in financial markets and might reflect a hierarchical processing of social nearness by human brains.
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Gomez, J. - C. (2005). Species comparative studies and cognitive development. Trends. Cognit. Sci., 9(3), 118–125.
Abstract: The comparative study of infant development and animal cognition brings to cognitive science the promise of insights into the nature and origins of cognitive skills. In this article, I review a recent wave of comparative studies conducted with similar methodologies and similar theoretical frameworks on how two core components of human cognition--object permanence and gaze following--develop in different species. These comparative findings call for an integration of current competing accounts of developmental change. They further suggest that evolution has produced developmental devices capable at the same time of preserving core adaptive components, and opening themselves up to further adaptive change, not only in interaction with the external environment, but also in interaction with other co-developing cognitive systems.
Keywords: Animals; Attention/physiology; Brain/*growth & development; Child, Preschool; Cognition/*physiology; Concept Formation/physiology; Dogs; Evolution; Fixation, Ocular; Gorilla gorilla; Humans; Infant; Learning/*physiology; Macaca mulatta; Mental Recall/physiology; Personal Construct Theory; Psychomotor Performance/physiology; Species Specificity
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Russell, J. L., Braccini, S., Buehler, N., Kachin, M. J., Schapiro, S. J., & Hopkins, W. D. (2005). Chimpanzee (Pan troglodytes) intentional communication is not contingent upon food. Anim. Cogn., 8(4), 263–272.
Abstract: Studies of great apes have revealed that they use manual gestures and other signals to communicate about distal objects. There is also evidence that chimpanzees modify the types of communicative signals they use depending on the attentional state of a human communicative partner. The majority of previous studies have involved chimpanzees requesting food items from a human experimenter. Here, these same communicative behaviors are reported in chimpanzees requesting a tool from a human observer. In this study, captive chimpanzees were found to gesture, vocalize, and display more often when the experimenter had a tool than when she did not. It was also found that chimpanzees responded differentially based on the attentional state of a human experimenter, and when given the wrong tool persisted in their communicative efforts. Implications for the referential and intentional nature of chimpanzee communicative signaling are discussed.
Keywords: *Animal Communication; Animals; *Feeding Behavior; Female; Humans; Male; Pan troglodytes/*psychology
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Panksepp, J. (2005). Affective consciousness: Core emotional feelings in animals and humans. Conscious Cogn, 14(1), 30–80.
Abstract: The position advanced in this paper is that the bedrock of emotional feelings is contained within the evolved emotional action apparatus of mammalian brains. This dual-aspect monism approach to brain-mind functions, which asserts that emotional feelings may reflect the neurodynamics of brain systems that generate instinctual emotional behaviors, saves us from various conceptual conundrums. In coarse form, primary process affective consciousness seems to be fundamentally an unconditional “gift of nature” rather than an acquired skill, even though those systems facilitate skill acquisition via various felt reinforcements. Affective consciousness, being a comparatively intrinsic function of the brain, shared homologously by all mammalian species, should be the easiest variant of consciousness to study in animals. This is not to deny that some secondary processes (e.g., awareness of feelings in the generation of behavioral choices) cannot be evaluated in animals with sufficiently clever behavioral learning procedures, as with place-preference procedures and the analysis of changes in learned behaviors after one has induced re-valuation of incentives. Rather, the claim is that a direct neuroscientific study of primary process emotional/affective states is best achieved through the study of the intrinsic (“instinctual”), albeit experientially refined, emotional action tendencies of other animals. In this view, core emotional feelings may reflect the neurodynamic attractor landscapes of a variety of extended trans-diencephalic, limbic emotional action systems-including SEEKING, FEAR, RAGE, LUST, CARE, PANIC, and PLAY. Through a study of these brain systems, the neural infrastructure of human and animal affective consciousness may be revealed. Emotional feelings are instantiated in large-scale neurodynamics that can be most effectively monitored via the ethological analysis of emotional action tendencies and the accompanying brain neurochemical/electrical changes. The intrinsic coherence of such emotional responses is demonstrated by the fact that they can be provoked by electrical and chemical stimulation of specific brain zones-effects that are affectively laden. For substantive progress in this emerging research arena, animal brain researchers need to discuss affective brain functions more openly. Secondary awareness processes, because of their more conditional, contextually situated nature, are more difficult to understand in any neuroscientific detail. In other words, the information-processing brain functions, critical for cognitive consciousness, are harder to study in other animals than the more homologous emotional/motivational affective state functions of the brain.
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Lafferty, K. D. (2005). Look what the cat dragged in: do parasites contribute to human cultural diversity? Behav. Process., 68(3), 279–282. |
Fox, N. A. (2004). Temperament and early experience form social behavior. Ann N Y Acad Sci, 1038, 171–178.
Abstract: Individual differences in the way persons respond to stimulation can have important consequences for their ability to learn and their choice of vocation. Temperament is the study of such individual differences, being thought of as the behavioral style of an individual. Common to all approaches in the study of temperament are the notions that it can be identified in infancy, is fairly stable across development, and influences adult personality. We have identified a specific temperament type in infancy that involves heightened distress to novel and unfamiliar stimuli. Infants who exhibit this temperament are likely, as they get older, to display behavioral inhibition-wariness and heightened vigilance of the unfamiliar-particularly in social situations. Our work has also described the underlying biology of this temperament and has linked it to neural systems supporting fear responses in animals. Children displaying behavioral inhibition are at-risk for behavioral problems related to anxiety and social withdrawal.
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Staunton, H. (2005). Mammalian sleep. Naturwissenschaften, 92(5), 203–220.
Abstract: This review examines the biological background to the development of ideas on rapid eye movement sleep (REM sleep), so-called paradoxical sleep (PS), and its relation to dreaming. Aspects of the phenomenon which are discussed include physiological changes and their anatomical location, the effects of total and selective sleep deprivation in the human and animal, and REM sleep behavior disorder, the latter with its clinical manifestations in the human. Although dreaming also occurs in other sleep phases (non-REM or NREM sleep), in the human, there is a contingent relation between REM sleep and dreaming. Thus, REM is taken as a marker for dreaming and as REM is distributed ubiquitously throughout the mammalian class, it is suggested that other mammals also dream. It is suggested that the overall function of REM sleep/dreaming is more important than the content of the individual dream; its function is to place the dreamer protagonist/observer on the topographical world. This has importance for the developing infant who needs to develop a sense of self and separateness from the world which it requires to navigate and from which it is separated for long periods in sleep. Dreaming may also serve to maintain a sense of 'I'ness or “self” in the adult, in whom a fragility of this faculty is revealed in neurological disorders.
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