Acuna, B. D., Sanes, J. N., & Donoghue, J. P. (2002). Cognitive mechanisms of transitive inference. Exp Brain Res, 146(1), 1–10.
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.
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Akins, C. K., Klein, E. D., & Zentall, T. R. (2002). Imitative learning in Japanese quail (Coturnix japonica) using the bidirectional control procedure. Anim Learn Behav, 30(3), 275–281.
Abstract: In the bidirectional control procedure, observers are exposed to a conspecific demonstrator responding to a manipulandum in one of two directions (e.g., left vs. right). This procedure controls for socially mediated effects (the mere presence of a conspecific) and stimulus enhancement (attention drawn to a manipulandum by its movement), and it has the added advantage of being symmetrical (the two different responses are similar in topography). Imitative learning is demonstrated when the observers make the response in the direction that they observed it being made. Recently, however, it has been suggested that when such evidence is found with a predominantly olfactory animal, such as the rat, it may result artifactually from odor cues left on one side of the manipulandum by the demonstrator. In the present experiment, we found that Japanese quail, for which odor cues are not likely to play a role, also showed significant correspondence between the direction in which the demonstrator and the observer push a screen to gain access to reward. Furthermore, control quail that observed the screen move, when the movement of the screen was not produced by the demonstrator, did not show similar correspondence between the direction of screen movement observed and that performed by the observer. Thus, with the appropriate control, the bidirectional procedure appears to be useful for studying imitation in avian species.
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Andersen, N. H., Norgaard, A., Jensen, T. J., & Ulstrup, J. (2002). Sequential unfolding of the two-domain protein Pseudomonas stutzeri cytochrome c4. Journal of Inorganic Biochemistry, 88(3-4), 316–327.
Abstract: P. stutzeri cytochrome c4 is a di-haem protein, composed of two globular domains each with His-Met coordinated haem, and a hydrogen bond network between the domains. The domain foldings are highly symmetric but with specific differences including structural differences of ligand coordination, and different spin states of the oxidised haem groups. We have studied unfolding of oxidised P. stutzeri cyt c4 induced thermally and by chemical denaturants. Horse heart cyt c was a reference molecule. Isothermal unfolding induced by guanidinium chloride and acid was followed by Soret, α/β, and 701-nm band absorption, and by far-UV circular dichroism spectroscopy. Multifarious patterns emerge, but the two domains clearly unfold sequentially. One phase, assigned to unfolding of the N-terminal domain, proceeds at guanidinium concentrations up to [approximate]1.0 M. This is followed by two overlapping phases at higher concentrations. The intermediate state maintains Fe-Met coordination, assigned to the C-terminal domain. Interdomain interaction is reflected in decreasing values of the cooperativity parameters. Differential scanning calorimetry shows a single peak, but two peaks appear when guanidinium chloride up to 0.4 M is present. This reflects different chemical action in chemical and thermal unfolding. Acid-induced unfolding kinetics was addressed by pH jumps using diode array stopped-flow techniques. Three kinetic phases in the 701 nm Fe-Met marker band, and four phases in the Soret and α/β bands, spanning 4-1000 ms could be distinguished on pH jumps from 7.5 to the range 2.5-3.5. In this range of time and pH cyt c appears to unfold in no more than two phases. Spectral properties of the kinetic intermediates could be identified. Sequential domain unfolding, formation of high-spin states, and an intermediate state with Fe-Met coordination to a single haem group are features of the unfolding kinetics.
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Appleby M. (2002). Consciousness, Cognition and Animal Welfare – J.K. Kirkwood, R.C. Hubrecht, S. Wickens, H. O'Leary, S. Oakley (Eds.), Universities Federation for Animal Welfare, 2001, 251 pp., Paperback, Supplement to Volume 10 of Animal Welfare, 15/US$ 30, ISSN 0962-7286. Appl. Anim. Behav. Sci., 77, 239–241.
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Appleby, M. (2002). Consciousness, Cognition and Animal Welfare: J.K. Kirkwood, R.C. Hubrecht, S. Wickens, H. O'Leary, S. Oakley (Eds.), Universities Federation for Animal Welfare, 2001, 251 pp., Paperback, Supplement to Volume 10 of Animal Welfare, [pound sign]15/US$ 30, ISSN 0962-7286. Appl. Anim. Behav. Sci., 77(3), 239–241.
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Aureli, F., Cords, M., & van Schaik, C. P. (2002). Conflict resolution following aggression in gregarious animals: a predictive framework. Anim. Behav., 64(3), 325–343.
Abstract: Knowledge of how animals manage their conflicts is critical for understanding the dynamics of social systems. During the last two decades research on gregarious animals, especially primates, has focused on the mechanisms of conflict management, mainly on friendly postconflict reunions (also called `reconciliation') in which former opponents exchange affiliative behaviour soon after an aggressive conflict. Our aim in this paper is to present a framework in which the costs and benefits of friendly postconflict reunions, both for each individual opponent and for their mutual relationship, are used to predict the patterning of postconflict resolution mechanisms in other gregarious animals. The framework predicts the occurrence of postconflict reunions in species that live in stable social units, have individualized relationships, and experience postconflict hostility, but especially in those in which intragroup aggression disrupts valuable relationships. The critical issue is whether aggressive conflicts occur between cooperative partners and whether the level of aggression is sufficient to jeopardize the benefits associated with such valuable relationships. We conclude by proposing four research priorities to evaluate the role of friendly reunions in negotiating relationships and the way they are themselves influenced by asymmetries in partner value and biological market effects. Copyright 2002 The Association for the Study of Animal Behaviour. Published by Elsevier Science Ltd. All rights reserved.
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Barnard, C. J., & Luo, N. (2002). Acquisition of dominance status affects maze learning in mice. Behav. Process., 60(1), 53–59.
Abstract: Learning is likely to be costly and thus subject to trade-off with other components of life history. An obvious prediction, therefore, is that investment in learning, and thus learning performance, will vary with individual life history strategy and the reproductive value of the learning outcome. We tested this idea in the context of social dominance in male laboratory mice, using a simple radial maze paradigm to compare the ability of high- and low-ranking male mice to track changing food location. We tested animals in randomly selected pairs before and after establishing aggressive rank relationships to distinguish intrinsic differences in learning ability from those attributable to acquiring high or low rank. There was no difference in learning between later dominants and subordinates prior to establishing rank relationships. After pairing, however, dominants showed a significantly greater percentage of correct responses, with the difference being greatest earlier in a sequence of trials. The percentage of correct responses also increased with the amount of aggression initiated during pairing. The results thus appeared to reflect a state-dependent change in learning associated with the aggressive social relationships formed during pairing.
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Barrey, E., Desliens, F., Poirel, D., Biau, S., Lemaire, S., Rivero, J. L. L., et al. (2002). Early evaluation of dressage ability in different breeds. Equine Vet J Suppl, (34), 319–324.
Abstract: Dressage is one of the Olympic equestrian sports practiced in several countries using different horse breeds. Specific characteristics of the walk, trot and canter are required for dressage. It has been assumed that some of these traits could be selected for genetically and contribute to dressage performance. The purpose of this study was to compare the walk, trot and conformation characteristics in young horses of different breeds used for dressage. A total of 142 horses age 3 years were classified into 3 groups of breeds (German, French and Spanish saddle horses) and tested using the same procedure. The skeletal conformation measurements were made by image analysis. Gait variables of the walk and trot were measured by the accelerometric gait analysis system Equimetrix. Discriminant analysis could explain the variability between the groups by taking into account the walk (P<0.0003), trot (P<0.0001) and conformation variables (P<0.0001). Many gait and conformation variables were significantly different between the breeds. In summary, the German horses had gait characteristics more adapted for dressage competition, and the results of this group could be used as a reference for early evaluation in dressage. Purebred Spanish horses could be considered as a reference for collected gaits used for farm work and old academic dressage. The gait and conformation tests could be applied in a breeding or crossing plan to detect more accurately young horses with good dressage ability.
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Barton, R. (2002). The evolutionary ecolgy of the primate brain. In P. C. Lee (Ed.), Comparative Primate Socioecology (pp. 167–204). Cambridge: Cambridge University Press.
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Bello, T. R. (2002). Practical treatment of body and open leg wounds of horses with bovine collagen, biosynthetic wound dressing and cyanoacrylate. Journal of Equine Veterinary Science, 22(4), 157–164.
Abstract: Horses with severe and deep lacerations are represented by ten cases in which treatment emphasized the use of bovine collagen preparations to promote controlled second-degree repair. Traumatized areas were tarsal, metatarsal, neck, forearm, metacarpal and pastern. Wound size changes were recorded. Depending on the wound type, the site was treated with antibiotic-steroid ointment, organic acid cream, sterile collagen particles, suspension or dressings protected by hydrogel dressing, non-adherent pads, occlusive skin dressings, roll gauze and elastic tape. In three cases, a fiberglas cast was applied over a hind leg wound and lacerated tendon for stability. When controlled granulation of the deeper wounds reached skin level, the area often was stabilized by only cyanoacrylate spray. As these cases presented a wide range of trauma each with a unique history, healing rates were based on initial measurements. An overall progression of wound reduction occurred at a predictable rate. The exogenous collagen formulations were used to stimulate controlled granulation, ie. to “jump start” the healing process. Collagen particles, suspension or dressings were packed into depressions, placed under suture lines, secured over abraded tissue, and placed under protective bandage or cast. To further evaluate the use of cyanoacrylate tissue spray in wound treatments, an additional ten cases are presented. The variety of wounds were produced experimentally in Center-owned ponies or provided as clinical cases. Wound size changes and healing progress were recorded. Wounds occurred on the neck, abdomen, metacarpal, metatarsal, fetlock and pastern areas. Depending on wound type, the site was treated with cyanoacrylate only; or treated as above until controlled granulation attained skin level. In one case punch grafts of skin were transferred from one foreleg to the opposite with the horse standing. Cyanoacrylate spray provided a water proof barrier protecting the wound from dirt, debris and insects as well as stabilizing full-thickness skin lacerations by bridging normal to traumatized skin allowing uninterrupted granulation and epithelialization. The use of a neck cradle prevented wound disturbance and stall confinement aided stabilization.
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