Hauser MD. (1997). Artifactual kinds and functional design features: what a primate understands without language. Cognition, 64, 285.
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Giraldeau, L. - A. (1997). The ecology of information use. In J. R. Krebs, & N. B. Davies (Eds.), Behavioural ecology : an evolutionary approach. Cambridge, Mass.: Blackwell Science.
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Gibson, K. T., Burbidge, H. M., & Anderson, B. H. (1997). Tendonitis of the branches of insertion of the superficial digital flexor tendon in horses. Aust Vet J, 75(4), 253–256.
Abstract: OBJECTIVE: To describe clinical findings, ultrasonographic features and outcome of injury to the branches of insertion of the superficial digital flexor (SDF) tendon in horses. DESIGN: Retrospective study of 14 cases. PROCEDURE: Fourteen Thoroughbred horses with tendonitis affecting the branches of insertion of the SDF tendon were examined for lameness, location and amount of swelling, and the presence of other musculoskeletal abnormalities. The flexor tendons were assessed by ultrasonographic examination, and recommendations were made for management of the cases. Outcome was assessed by re-examination of some horses, direct communication with the owner or trainer, and examination of race records. RESULTS: The lateral SDF branch was affected in 10 horses; the medial branch in three, and both branches in one horse. Two horses had concurrent injuries to the SDF tendon in the metacarpal region of the contralateral limb. Ultrasonographic findings included swelling of the affected SDF branch, peritendinous fluid accumulation, disruption of normal fibre alignment on sagittal scan, and variable loss of echogenicity. As healing occurred, there was return of normal echogenicity, but normal fibre alignment did not return completely and apparent adhesions formed between the affected SDF branch and adjacent structures. Seven of 10 horses which returned to their previous use were able to compete without further tendon injury. Recurrence of injury occurred in one case, and another two horses developed tendonitis in the metacarpal region. One horse was retired from racing but was able to compete at dressage without recurrence of injury. Two horses were retired for breeding without returning to training, and one horse was sold and lost to follow up but did not race. CONCLUSION: The prognosis is fair for return to previous use following injury to the branches of insertion of the SDF tendon in athletic horses.
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Gallup, G. G. J. (1997). On the rise and fall of self-conception in primates. Ann N Y Acad Sci, 818, 72–82.
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Galloux, P., & Barrey, E. (1997). Components of the total kinetic moment in jumping horses. Equine Vet J Suppl, (23), 41–44.
Abstract: Thirty horses were filmed with a panning camera operating at 50 frames/s as they jumped over a 1.20 x 1.20 m fence. The markers of 9 joints on the horse and 7 joints on the rider were tracked in 2D with the TrackEye system. The centre of gravity and moment of inertia of each segment were calculated using a geometric algorithm and a cylindric model, respectively. The kinetic moment of each part of the horse was calculated after filtering, and resampling of data. This method showed the relative contribution of each body segment to the body overall rotation during the take-off, jump and landing phases. It was found that the trunk, hindlimbs and head-neck had the greatest influence. The coordination between the motion of the body segments allowed the horse to control its angular speed of rotation over the fence. This remained nearly constant during the airborne phase (120 +/- 5 degrees/s). During the airborne phase, the kinetic moment was constant because its value was equal to the moment of the external forces (722 +/- 125 kg x m2/s).
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Gallagher, M., & Rapp, P. R. (1997). The Use Of Animal Models To Study The Effects Of Aging On Cognition. Annual Review of Psychology, 48(1), 339–370.
Abstract: This review addresses the importance of animal models for understanding the effects of normal aging on the brain and cognitive functions. First, studies of laboratory animals can help to distinguish between healthy aging and pathological conditions that may contribute to cognitive decline late in life. Second, research on individual differences in aging, a theme of interest in studies of elderly human beings, can be advanced by the experimental control afforded in the use of animal models. The review offers a neuropsychological framework to compare the effects of aging in human beings, monkeys, and rodents. We consider aging in relation to the role of the medial temporal lobe in memory, the information processing functions of the prefrontal cortex in the strategic use of memory, and the regulation of attention by distributed neural circuitry. We also provide an overview of the neurobiological effects of aging that may account for alterations in psychological functions.
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Foster, T. M., Temple, W., Cameron, B., & Poling, A. (1997). Demand curves for food in hens: Similarity under fixed-ratio and progressive-ratio schedules. Behav. Process., 39(2), 177–185.
Abstract: Demand curves were generated for five domestic hens under progressive-ratio 5 schedules of food delivery and under fixed-ratio schedules of food delivery that began at fixed-ratio 5 and were incremented by 5 each session. All sessions ended after 10 consecutive minutes without a response. Although response rates at a given ratio were higher under the progressive-ratio schedule, all hens completed higher ratios under the fixed-ratio schedule. Similar, but not identical, demand curves were generated under progressive-ratio and fixed-ratio schedules. Under both schedules, consumption (reinforcers earned) decreased as cost (ratio size) increased. Data generally were well described by an equation in which elasticity of demand is constant, although an equation in which elasticity could vary accounted for slightly more of the variance.
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Foster, T. M., Matthews, L. R., Temple, W., & Poling, A. (1997). Concurrent schedule performance in domestic goats: persistent undermatching. Behav. Process., 40(3), 231–237.
Abstract: Performance of nine domestic goats responding under concurrent variable-interval variable-interval schedules of food delivery was examined, with results analyzed in terms of the generalized matching equation. Substantial undermatching of response and time allocation ratios to obtained reinforcement ratios was evident. Post-reinforcement pause time ratios approximately matched obtained reinforcement ratios. Subtracting these times from total time allocation values yielded net time allocation ratios, which undermatched obtained reinforcement ratios to a greater degree than whole-session time allocation ratios. Slopes of regression lines relating behavioral outputs to environmental inputs characteristically were below 0.6, which is similar to previous findings in dairy cows tested under comparable conditions.
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Flannery, B. (1997). Relational discrimination learning in horses. Appl. Anim. Behav. Sci., 54(4), 267–280.
Abstract: This series of studies investigated horses' ability to learn the concept of sameness under several different conditions. Before experimentation began, three horses were shaped to touch individually presented stimuli with their muzzles, and then to make two responses to two matching cards from an array of three. A modified version of the identity matching-to-sample (IMTS) procedure was used to present stimuli in a variety of configural arrangements on a barn wall (Experiment 1 and Experiment 2), and on a flat panel mounted to a barn door (Experiment 3). The task in each experiment was to select the two stimulus cards that were the same (either circles or Xs) and to avoid the nonmatching stimulus card (either a star or a square). In Experiment 1, the mean accuracy rate for selecting the matching alternatives was 74%. The horses' accuracy levels reached a mean level of 83% during Experiment 2, in which they received additional trials and an intermittent secondary reinforcement schedule. In Experiment 3, when the stimuli were moved further apart from each other within arrangements and were presented on a novel background, the mean accuracy rate was 73%. These data demonstrate that horses can learn complex discrimination problems involving the concept of sameness, and that they are able to generalize this learning to a novel stimulus presentation situation. These results also suggest that a relational discrimination test may be useful for assessing horses' learning ability and the level of training appropriate for individual horses.
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Dusek, J. A., & Eichenbaum, H. (1997). The hippocampus and memory for orderly stimulus relations. Proc. Natl. Acad. Sci. U.S.A., 94(13), 7109–7114.
Abstract: Human declarative memory involves a systematic organization of information that supports generalizations and inferences from acquired knowledge. This kind of memory depends on the hippocampal region in humans, but the extent to which animals also have declarative memory, and whether inferential expression of memory depends on the hippocampus in animals, remains a major challenge in cognitive neuroscience. To examine these issues, we used a test of transitive inference pioneered by Piaget to assess capacities for systematic organization of knowledge and logical inference in children. In our adaptation of the test, rats were trained on a set of four overlapping odor discrimination problems that could be encoded either separately or as a single representation of orderly relations among the odor stimuli. Normal rats learned the problems and demonstrated the relational memory organization through appropriate transitive inferences about items not presented together during training. By contrast, after disconnection of the hippocampus from either its cortical or subcortical pathway, rats succeeded in acquiring the separate discrimination problems but did not demonstrate transitive inference, indicating that they had failed to develop or could not inferentially express the orderly organization of the stimulus elements. These findings strongly support the view that the hippocampus mediates a general declarative memory capacity in animals, as it does in humans.
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