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Author Acuna, B.D.; Sanes, J.N.; Donoghue, J.P. doi  openurl
  Title Cognitive mechanisms of transitive inference Type Journal Article
  Year 2002 Publication Experimental brain research. Experimentelle Hirnforschung. Experimentation cerebrale Abbreviated Journal Exp Brain Res  
  Volume 146 Issue 1 Pages 1-10  
  Keywords Adolescent; Adult; Attention/*physiology; Cognition/*physiology; Female; Humans; Learning/physiology; Linear Models; Male; Photic Stimulation; Psychomotor Performance/physiology; Reaction Time/physiology  
  Abstract We examined how the brain organizes interrelated facts during learning and how the facts are subsequently manipulated in a transitive inference (TI) paradigm (e.g., if A<B and B<C, then A<C). This task determined features such as learned facts and behavioral goals, but the learned facts could be organized in any of several ways. For example, if one learns a list by operating on paired items, the pairs may be stored individually as separate facts and reaction time (RT) should decrease with learning. Alternatively, the pairs may be stored as a single, unified list, which may yield a different RT pattern. We characterized RT patterns that occurred as participants learned, by trial and error, the predetermined order of 11 shapes. The task goal was to choose the shape occurring closer to the end of the list, and feedback about correctness was provided during this phase. RT increased even as its variance decreased during learning, suggesting that the learnt knowledge became progressively unified into a single representation, requiring more time to manipulate as participants acquired relational knowledge. After learning, non-adjacent (NA) list items were presented to examine how participants reasoned in a TI task. The task goal also required choosing from each presented pair the item occurring closer to the list end, but without feedback. Participants could solve the TI problems by applying formal logic to the previously learnt pairs of adjacent items; alternatively, they could manipulate a single, unified representation of the list. Shorter RT occurred for NA pairs having more intervening items, supporting the hypothesis that humans employ unified mental representations during TI. The response pattern does not support mental logic solutions of applying inference rules sequentially, which would predict longer RT with more intervening items. We conclude that the brain organizes information in such a way that reflects the relations among the items, even if the facts were learned in an arbitrary order, and that this representation is subsequently used to make inferences.  
  Address (down) Department of Neuroscience, Box 1953, Brown Medical School, Providence, RI 02912, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0014-4819 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12192572 Approved no  
  Call Number refbase @ user @ Serial 602  
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Author Hall, R.A.; Broom, A.K.; Smith, D.W.; Mackenzie, J.S. openurl 
  Title The ecology and epidemiology of Kunjin virus Type Journal Article
  Year 2002 Publication Current Topics in Microbiology and Immunology Abbreviated Journal Curr Top Microbiol Immunol  
  Volume 267 Issue Pages 253-269  
  Keywords Animals; Culicidae/virology; Ecosystem; Horse Diseases/etiology; Horses; Humans; Insect Vectors; Population Surveillance; West Nile Fever/*epidemiology/*etiology/veterinary; West Nile virus/classification/genetics/immunology/*isolation & purification  
  Abstract  
  Address (down) Department of Microbiology and Parasitology, School of Molecular and Microbial Sciences, The University of Queensland, St. Lucia, Queensland 4072, Australia  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0070-217X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12082993 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2642  
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Author Waite, T.A. doi  openurl
  Title Interruptions improve choice performance in gray jays: prolonged information processing versus minimization of costly errors Type Journal Article
  Year 2002 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 5 Issue 4 Pages 209-214  
  Keywords Animals; *Behavior, Animal; *Choice Behavior; Female; Learning; Male; Models, Biological; Motivation; Reinforcement Schedule; Songbirds/*physiology; Time Factors  
  Abstract Under the assumption that selection favors minimization of costly errors, erroneous choice may be common when its fitness cost is low. According to an adaptive-choice model, this cost depends on the rate at which an animal encounters the choice: the higher this rate, the smaller the cost of choosing a less valuable option. Errors should thus be more common when interruptions to foraging are shorter. A previous experiment supported this prediction: gray jays, Perisoreus canadensis, were more error prone when subjected to shorter delays to access to food rewards. This pattern, though, is also predicted by an attentional-constraints model. Because the subjects were able to inspect the rewards during delays, their improved performance when subjected to longer delays could have been a byproduct of the experimentally prolonged opportunity for information processing. To evaluate this possibility, a follow-up experiment manipulated both delay to access and whether rewards could be inspected during delays. Depriving jays of the opportunity to inspect rewards (using opaque lids) induced only a small, nonsignificant increase in error rate. This effect was independent of length of delay and so the jays' improved performance when subjected to longer delays was not simply a byproduct of prolonged information processing. More definitively, even when the jays were prevented from inspecting rewards during delays, their performance improved when subjected to longer delays. The findings are thus consistent with the adaptive-choice model.  
  Address (down) Department of Evolution, Ecology, and Organismal Biology, Ohio State University, 1735 Neil Avenue, Columbus, OH 43210-1293, USA. waite.1@osu.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12461598 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2592  
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Author Soproni, K.; Miklósi, Á.; Topál, J.; Csányi, V. url  doi
openurl 
  Title Dogs' (Canis familiaris) responsiveness to human pointing gestures Type Journal Article
  Year 2002 Publication Journal of Comparative Psychology (Washington, D.C. : 1983) Abbreviated Journal J Comp Psychol  
  Volume 116 Issue 1 Pages 27-34  
  Keywords Analysis of Variance; Animals; *Behavior, Animal; Choice Behavior; Dogs/*psychology; Female; Gestures; Male; *Recognition (Psychology); Species Specificity  
  Abstract In a series of 3 experiments, dogs (Canis familiaris) were presented with variations of the human pointing gesture: gestures with reversed direction of movement, cross-pointing, and different arm extensions. Dogs performed at above chance level if they could see the hand (and index finger) protruding from the human body contour. If these minimum requirements were not accessible, dogs still could rely on the body position of the signaler. The direction of movement of the pointing arm did not influence the performance. In summary, these observations suggest that dogs are able to rely on relatively novel gestural forms of the human communicative pointing gesture and that they are able to comprehend to some extent the referential nature of human pointing.  
  Address (down) Department of Ethology, Eotvos Lorand University, Budapest, Hungary. krisztinasoproni@hotmail.com  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0735-7036 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11926681 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4962  
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Author Santamaria, S.; Back, W.; van Weeren, P.R.; Knaap, J.; Barneveld, A. openurl 
  Title Jumping characteristics of naive foals: lead changes and description of temporal and linear parameters Type Journal Article
  Year 2002 Publication Equine Veterinary Journal. Supplement Abbreviated Journal Equine Vet J Suppl  
  Volume Issue 34 Pages 302-307  
  Keywords Animals; Animals, Newborn/*physiology; Biomechanics; Female; Forelimb/physiology; Gait/*physiology; Hindlimb/physiology; Horses/*physiology; Locomotion/*physiology; Male  
  Abstract The selection of foals as future showjumpers remains a subjective process based on qualitative parameters; and hence, frequently suffers from disparity in the criteria used by experts in the field. A detailed biomechanical description of foals while jumping would be most helpful in providing a better basis for the accurate assessment of their future athletic ability. The Qualisys Pro Reflex system was used to capture 3-dimensional kinematics of 41 Dutch Warmblood foals age 6 months free jumping a vertical fence, preceded by a cross pole fence. The left lead was the most preferred lead for both the fore- and hindlimbs, from the landing following the cross poles to the first move-off stride after clearing the vertical fence. The foals displayed a high incidence of rotary gallop during both the jump stride (divided into take-off, jump suspension and landing) and the first move-off stride, while change of lead was frequently observed during jump suspension. At the take-off side of the fence, the trailing forelimb in the last approach stride was placed furthest from the fence, whereas the trailing hindlimb at take-off was placed closest (P<0.05). At the landing side, the trailing forelimb was the closest and the leading hindlimb of the move-off stride 1 was the furthest (P<0.05). The trailing forelimb in the approach stride 1 had a significantly longer stance phase duration than the leading forelimb. At landing, the leading forelimb stance phase lasted longer than that of the trailing forelimb (P<0.05). The hindlimbs did not differ in their stance phase duration at take-off. The height reached by the hooves above the fence top was significantly greater in the hind limbs (P<0.05). In addition, the hindlimbs (97.1 +/- 2.6%) shortened more than the forelimbs (92.6 +/- 5.7%) (P<0.05). It is concluded that the overall jumping technique of foals is similar to that reported in literature for mature horses. If the patterns are consistent throughout the rearing period, the quantitative analysis of the kinematics of free jumping foals may provide a valid quantitative basis for early selection.  
  Address (down) Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht, The Netherlands  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Area Expedition Conference  
  Notes PMID:12405705 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3784  
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Author Quiroz-Rothe, E.; Novales, M.; Aguilera-Tejero, E.; Rivero, J.L.L. openurl 
  Title Polysaccharide storage myopathy in the M. longissimus lumborum of showjumpers and dressage horses with back pain Type Journal Article
  Year 2002 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J  
  Volume 34 Issue 2 Pages 171-176  
  Keywords Amylases/analysis; Animals; Back Pain/etiology/*veterinary; Biopsy; Carbohydrate Metabolism, Inborn Errors/diagnosis/pathology/*veterinary; Diagnosis, Differential; Glycogen/analysis; Horse Diseases/*diagnosis/pathology; Horses; Microscopy, Electron; Muscle, Skeletal/pathology; Muscular Diseases/diagnosis/pathology/*veterinary; Polysaccharides/*metabolism; Rhabdomyolysis/diagnosis/pathology/veterinary  
  Abstract This study was designed to investigate whether horses with clinical signs of back pain due to suspected soft tissue injuries were affected by polysaccharide storage myopathy (PSSM). Diagnosis of PSSM in muscle biopsies obtained from the M. longissimus lumborum of 5 showjumpers and 4 dressage horses with a history of back pain is reported. M. longissimus lumborum biopsies of these horses were characterised histopathologically and in 3/9 cases also by electron microscopy. Observations were compared with M. gluteus biopsies of the same horses, and with M. gluteus biopsies obtained from 6 Standardbreds with recurrent exertional rhabdomyolysis and from 6 healthy trotters. M. longissimus biopsies from horses with back pain showed pathognomonic signs of PSSM, i.e. high glycogen and/or abnormal complex amylase-resistant polysaccharide deposits. Similar features were found in M. gluteus biopsies of the same horses. Sections of horses with rhabdomyolysis had increased PAS stain when compared with healthy horses, but did not show amylase-resistant material. Qualitative observations were corroborated by quantitative histochemistry (optical densities) of sections stained with PAS and amylase PAS. This study demonstrated the presence of PSSM in the M. longissimus of showjumpers and dressage horses with back pain and indicates that epaxial muscle biopsy is an option in diagnosing back problems in horses when clinical examination and imaging techniques do not provide a precise diagnosis.  
  Address (down) Department of Comparative Anatomy, Faculty of Veterinary Science, University of Cordoba, Spain  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0425-1644 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:11905436 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3727  
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Author Nicol, C.J.; Davidson, H.P.D.; Harris, P.A.; Waters, A.J.; Wilson, A.D. openurl 
  Title Study of crib-biting and gastric inflammation and ulceration in young horses Type Journal Article
  Year 2002 Publication The Veterinary record Abbreviated Journal Vet. Rec.  
  Volume 151 Issue 22 Pages 658-662  
  Keywords Animal Husbandry/methods; Animals; Antacids/therapeutic use; *Behavior, Animal; Diet/veterinary; Endoscopy, Gastrointestinal/veterinary; Feces/chemistry; Female; Gastritis/diet therapy/physiopathology/*veterinary; Horse Diseases/diet therapy/*physiopathology/psychology; Horses; Hydrogen-Ion Concentration; Male; Random Allocation; Stereotyped Behavior/*physiology; Stomach Ulcer/diet therapy/physiopathology/*veterinary; Treatment Outcome; Weaning  
  Abstract Nineteen young horses that had recently started to perform the stereotypy of crib-biting were compared with 16 non-stereotypic horses for 14 weeks. After initial observations of their behaviour and an endoscopic examination of the condition of their stomachs, the horses were randomly allocated to a control or an antacid diet At the start of the trial, the stomachs of the crib-biting foals were significantly more ulcerated and inflamed than the stomachs of the normal foals. In addition, the faecal pH of the crib-biting foals (6.05) was significantly lower than that of the normal foals (6.58). The antacid diet resulted in a significant improvement in the condition of the horses' stomachs. The crib-biting behaviour declined in most of the foals, regardless of their diet, but tended to decline to a greater extent in the foals on the antacid diet.  
  Address (down) Department of Clinical Veterinary Science, University of Bristol, Langford House, Bristol BS40 5DU  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0042-4900 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12498408 Approved no  
  Call Number refbase @ user @ Serial 83  
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Author Dugatkin, L.A. doi  openurl
  Title Animal cooperation among unrelated individuals Type Journal Article
  Year 2002 Publication Die Naturwissenschaften Abbreviated Journal Naturwissenschaften  
  Volume 89 Issue 12 Pages 533-541  
  Keywords Animals; Phylogeny; *Social Behavior; Species Specificity  
  Abstract The evolution of cooperation has long been a topic near and dear to the hearts of behavioral and evolutionary ecologists. Cooperative behaviors run the gamut from fairly simple to very complicated and there are a myriad of ways to study cooperation. Here I shall focus on three paths that have been delineated in the study of intraspecific cooperation among unrelated individuals: reciprocity, byproduct mutualism, and group selection. In each case, I attempt to delineate the theory underlying each of these paths and then provide examples from the empirical literature. In addition, I shall briefly touch upon some recent work that has attempted to examine (or re-examine) the role of cognition and phylogeny in the study of cooperative behavior. While empirical and theoretical work has made significant strides in the name of better understanding the evolution and maintenance of cooperative behavior in animals, much work remains for the future. “From the point of view of the moralist, the animal world is on about the same level as the gladiator's show. The creatures are fairly well treated, and set to fight; whereby the strongest, the swiftest and the cunningest live to fight another day. The spectator has no need to turn his thumb down, as no quarter is given em leader the weakest and the stupidest went to the wall, while the toughest and the shrewdest, those who were best fitted to cope with their circumstances, but not the best in any other way, survived. Life was a continuous free fight, and em leader a war of each against all was the normal state of existence.” (Huxley 1888)  
  Address (down) Department of Biology, University of Louisville, Louisville, KY 40292, USA. lee.dugatkin@louisville.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-1042 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12536274 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2797  
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Author Earley, R.L.; Dugatkin, L.A. doi  openurl
  Title Eavesdropping on visual cues in green swordtail (Xiphophorus helleri) fights: a case for networking Type Journal Article
  Year 2002 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume 269 Issue 1494 Pages 943-952  
  Keywords *Aggression; Animals; *Behavior, Animal; *Cyprinodontiformes; Female; Male  
  Abstract Aggressive contests probably occur in networking environments where information about fighting ability is conveyed both to an opponent and to individuals peripheral to the fight itself, the bystanders. Our primary aim was to investigate the relative influences of eavesdropping and prior social experience on the dynamics of aggressive contests in Xiphophorus helleri. A bystander's ability to witness an encounter was manipulated using clear, one-way mirror, and opaque partitions. After watching (or not watching) the initial contest, the bystander encountered either the winner or loser of the bout. Treatment comparisons of bystander-winner or bystander-loser contest dynamics indicated the presence or absence of winner, loser, or eavesdropping effects. Winner and loser effects had negligible influences on bystander contest dynamics. Eavesdropping significantly reduced the bystander's propensity to initiate aggression, escalate, and win against seen winners regardless of whether the watched bout had escalated or not. Though eavesdropping had relatively little effect on bystander-loser contest dynamics, bystanders were less prone to initiate aggression and win against losers that had escalated in the witnessed bout. Thus, bystanders appear to preferentially retain and utilize information gained about potentially dangerous opponents (winners or persistent losers). Our data lend clear support for the importance of eavesdropping in visually based aggressive signalling systems.  
  Address (down) Department of Biology, Life Science, Room 139, University of Louisville, Louisville, KY 40292, USA. rlearl01@athena.louisville.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12028778 Approved no  
  Call Number refbase @ user @ Serial 498  
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Author Viscido, S.V.; Miller, M.; Wethey, D.S. openurl 
  Title The dilemma of the selfish herd: the search for a realistic movement rule Type Journal Article
  Year 2002 Publication Journal of theoretical biology Abbreviated Journal J. Theor. Biol.  
  Volume 217 Issue 2 Pages 183-194  
  Keywords Animals; *Behavior, Animal; *Mass Behavior; Models, Biological; *Motor Activity; Predatory Behavior  
  Abstract The selfish herd hypothesis predicts that aggregations form because individuals move toward one another to minimize their own predation risk. The “dilemma of the selfish herd” is that movement rules that are easy for individuals to follow, fail to produce true aggregations, while rules that produce aggregations require individual behavior so complex that one may doubt most animals can follow them. If natural selection at the individual level is responsible for herding behavior, a solution to the dilemma must exist. Using computer simulations, we examined four different movement rules. Relative predation risk was different for all four movement rules (p<0.05). We defined three criteria for measuring the quality of a movement rule. A good movement rule should (a) be statistically likely to benefit an individual that follows it, (b) be something we can imagine most animals are capable of following, and (c) result in a centrally compact flock. The local crowded horizon rule, which allowed individuals to take the positions of many flock-mates into account, but decreased the influence of flock-mates with distance, best satisfied these criteria. The local crowded horizon rule was very sensitive to the animal's perceptive ability. Therefore, the animal's ability to detect its neighbors is an important factor in the dynamics of group formation.  
  Address (down) Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208, USA. viscido@u.washington.edu  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-5193 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:12202112 Approved no  
  Call Number refbase @ user @ Serial 554  
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