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Author Vallortigara, G.; Rogers, L.J. url  doi
openurl 
  Title Survival with an asymmetrical brain: advantages and disadvantages of cerebral lateralization Type Journal Article
  Year (up) 2005 Publication The Behavioral and Brain Sciences Abbreviated Journal Behav Brain Sci  
  Volume 28 Issue 4 Pages 575-89; discussion 589-633  
  Keywords Animals; Attention/*physiology; Behavior/*physiology; Behavior, Animal/*physiology; Dominance, Cerebral/*physiology; *Evolution; Humans; Models, Biological; Visual Perception/physiology  
  Abstract Recent evidence in natural and semi-natural settings has revealed a variety of left-right perceptual asymmetries among vertebrates. These include preferential use of the left or right visual hemifield during activities such as searching for food, agonistic responses, or escape from predators in animals as different as fish, amphibians, reptiles, birds, and mammals. There are obvious disadvantages in showing such directional asymmetries because relevant stimuli may be located to the animal's left or right at random; there is no a priori association between the meaning of a stimulus (e.g., its being a predator or a food item) and its being located to the animal's left or right. Moreover, other organisms (e.g., predators) could exploit the predictability of behavior that arises from population-level lateral biases. It might be argued that lateralization of function enhances cognitive capacity and efficiency of the brain, thus counteracting the ecological disadvantages of lateral biases in behavior. However, such an increase in brain efficiency could be obtained by each individual being lateralized without any need to align the direction of the asymmetry in the majority of the individuals of the population. Here we argue that the alignment of the direction of behavioral asymmetries at the population level arises as an “evolutionarily stable strategy” under “social” pressures occurring when individually asymmetrical organisms must coordinate their behavior with the behavior of other asymmetrical organisms of the same or different species.  
  Address Department of Psychology and B.R.A.I.N. Centre for Neuroscience, University of Trieste, 34123 Trieste, Italy. vallorti@univ.trieste.it  
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  Series Volume Series Issue Edition  
  ISSN 0140-525X ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16209828 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4622  
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Author Ventolini, N.; Ferrero, E.A.; Sponza, S.; Della Chiesa, A.; Zucca, P.; Vallortigara, G. url  doi
openurl 
  Title Laterality in the wild: preferential hemifield use during predatory and sexual behaviour in the black-winged stilt Type Journal Article
  Year (up) 2005 Publication Animal Behaviour Abbreviated Journal Anim. Behav.  
  Volume 69 Issue 5 Pages 1077-1084  
  Keywords  
  Abstract We recorded preferential use of the left and right monocular visual field in black-winged stilts, Himantopus himantopus, during predatory pecking and during courtship and mating behaviour in a naturalistic setting. The stilts had a population-level preference for using their right monocular visual field before predatory pecking; pecks that followed right-hemifield detection were more likely to be successful than pecks that followed left-hemifield detection, as evinced by the occurrence of swallowing and shaking head movements after pecking. In contrast, shaking behaviour, a component of courtship displays, and copulatory attempts by males were more likely to occur when females were seen with the left monocular visual field. Asymmetric hemifield use observed in natural conditions raises interesting issues as to the costs and benefits of population-level behavioural lateralization in wild animals.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-3472 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5589  
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Author Chiesa, A.D.; Pecchia, T.; Tommasi, L.; Vallortigara, G. doi  openurl
  Title Multiple landmarks, the encoding of environmental geometry and the spatial logics of a dual brain Type Journal Article
  Year (up) 2006 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 9 Issue 4 Pages 281-293  
  Keywords Animals; Association Learning/*physiology; Chickens; *Cues; Dominance, Cerebral/*physiology; *Environment; Exploratory Behavior/*physiology; Logic; Space Perception/*physiology; Spatial Behavior/physiology  
  Abstract A series of place learning experiments was carried out in young chicks (Gallus gallus) in order to investigate how the geometry of a landmark array and that of a walled enclosure compete when disoriented animals could rely on both of them to re-orient towards the centre of the enclosure. A square-shaped array (four wooden sticks) was placed in the middle of a square-shaped enclosure, the two structures being concentric. Chicks were trained to ground-scratch to search for food hidden in the centre of the enclosure (and the array). To check for effects of array degradation, one, two, three or all landmarks were removed during test trials. Chicks concentrated their searching activity in the central area of the enclosure, but their accuracy was inversely contingent on the number of landmarks removed; moreover, the landmarks still present within the enclosure appeared to influence the shape of the searching patterns. The reduction in the number of landmarks affected the searching strategy of chicks, suggesting that they had focussed mainly on local cues when landmarks were present within the enclosure. When all the landmarks were removed, chicks searched over a larger area, suggesting an absolute encoding of distances from the local cues and less reliance on the relationships provided by the geometry of the enclosure. Under conditions of monocular vision, chicks tended to rely on different strategies to localize the centre on the basis of the eye (and thus the hemisphere) in use, the left hemisphere attending to details of the environment and the right hemisphere attending to the global shape.  
  Address Department of Psychology and B.R.A.I.N. Centre for Neuroscience, University of Trieste, via S. Anastasio 12, 34100, Trieste, Italy  
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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:16941155 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2443  
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Author Zucca, P.; Milos, N.; Vallortigara, G. doi  openurl
  Title Piagetian object permanence and its development in Eurasian jays (Garrulus glandarius) Type Journal Article
  Year (up) 2007 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 10 Issue 2 Pages 243-258  
  Keywords Animals; *Behavior, Animal; Birds/*physiology; *Cognition; *Cues  
  Abstract Object permanence in Eurasian jays (Garrulus glandarius) was investigated using a complete version of the Uzgiris and Hunt scale 1. Nine hand-raised jays were studied, divided into two groups according to their different developmental stages (experiment 1, older jays: 2-3 months old, n = 4; experiment 2, younger jays: 15 days old, n = 5). In the first experiment, we investigated whether older jays could achieve piagetian stage 6 of object permanence. Tasks were administered in a fixed sequence (1-15) according to the protocols used in other avian species. The aim of the second experiment was to check whether testing very young jays before their development of “neophobia” could influence the achievement times of piagetian stages. Furthermore, in this experiment tasks were administered randomly to investigate whether the jays' achievement of stage 6 follows a fixed sequence related to the development of specific cognitive abilities. All jays tested in experiments 1 and 2 fully achieved piagetian stage 6 and no “A not B” errors were observed. Performance on visible displacement tasks was better than performance on invisible ones. The results of experiment 2 show that “neophobia” affected the response of jays in terms of achievement times; the older jays in experiment 1 took longer to pass all the tasks when compared with the younger, less neophobic, jays in experiment 2. With regard to the achieving order, jays followed a fixed sequence of acquisition in experiment 2, even if tasks were administered randomly, with the exception of one subject. The results of these experiments support the idea that piagetian stages of cognitive development exist in avian species and that they progress through relatively fixed sequences.  
  Address Department of Psychology, Laboratory of Animal Cognition and Comparative Neuroscience, Via S. Anastasio 12, 34100, Trieste, Italy. zucca@units.it  
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  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17242935 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2423  
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Author Chiandetti, C.; Regolin, L.; Sovrano, V.A.; Vallortigara, G. doi  openurl
  Title Spatial reorientation: the effects of space size on the encoding of landmark and geometry information Type Journal Article
  Year (up) 2007 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 10 Issue 2 Pages 159-168  
  Keywords Animals; Chickens/*physiology; *Feeding Behavior; Male; Orientation/*physiology; Pattern Recognition, Visual/*physiology; *Space Perception  
  Abstract The effects of the size of the environment on animals' spatial reorientation was investigated. Domestic chicks were trained to find food in a corner of either a small or a large rectangular enclosure. A distinctive panel was located at each of the four corners of the enclosures. After removal of the panels, chicks tested in the small enclosure showed better retention of geometrical information than chicks tested in the large enclosure. In contrast, after changing the enclosure from a rectangular-shaped to a square-shaped one, chicks tested in the large enclosure showed better retention of landmark (panels) information than chicks tested in the small enclosure. No differences in the encoding of the overall arrangement of landmarks were apparent when chicks were tested for generalisation in an enclosure differing from that of training in size together with a transformation (affine transformation) that altered the geometric relations between the target and the shape of the environment. These findings suggest that primacy of geometric or landmark information in reorientation tasks depends on the size of the experimental space, likely reflecting a preferential use of the most reliable source of information available during visual exploration of the environment.  
  Address Department of Psychology and B.R.A.I.N. Centre for Neuroscience, University of Trieste, Via S. Anastasio 12, 34123, Trieste, Italy. cchiandetti@univ.trieste.it  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:17136416 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2433  
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Author Clara, E.; Regolin, L.; Vallortigara, G.; Rogers, L. doi  openurl
  Title Perception of the stereokinetic illusion by the common marmoset (Callithrix jacchus) Type Journal Article
  Year (up) 2007 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 10 Issue 2 Pages 135-140  
  Keywords Animals; Behavior, Animal/*physiology; Callithrix/*physiology; Female; Male; *Optical Illusions; Pattern Recognition, Visual/*physiology  
  Abstract Stereokinetic illusions have never been investigated in non-human primates, nor in other mammalian species. These illusions consist in the perception of a 3D solid object when certain 2D stimuli are rotated slowly in the plane perpendicular to the line of sight. The ability to perceive the stereokinetic illusion was investigated in the common marmoset (Callithrix jacchus). Four adult marmosets were trained to discriminate between a solid cylinder and a solid cone for food reward. Once learning criterion was reached, the marmosets were tested in sets of eight probe trials in which the two solid objects used at training were replaced by two rotating 2D stimuli. Only one of these stimuli produced, at least to the human observer, the stereokinetic illusion corresponding to the solid object previously reinforced. At test, the general behaviour and the total time spent by the marmosets observing each stimulus were recorded. The subjects stayed longer near the stimulus producing the stereokinetic illusion corresponding to the solid object reinforced at training than they did near the illusion corresponding to the previously non-rewarded stimulus. Hence, the common marmosets behaved as if they could perceive stereokinetic illusions.  
  Address Centre for Neuroscience and Animal Behaviour, University of New England, Armidale, NSW, 2351, Australia. elena.clara@unipd.it  
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  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16924457 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2445  
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Author Sovrano, V.A.; Bisazza, A.; Vallortigara, G. doi  openurl
  Title How fish do geometry in large and in small spaces Type Journal Article
  Year (up) 2007 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 10 Issue 1 Pages 47-54  
  Keywords Animals; *Association Learning; Color Perception; Cues; *Discrimination Learning; *Distance Perception; *Fishes; Male; Pattern Recognition, Visual; Social Environment; *Space Perception; Visual Perception  
  Abstract It has been shown that children and non-human animals seem to integrate geometric and featural information to different extents in order to reorient themselves in environments of different spatial scales. We trained fish (redtail splitfins, Xenotoca eiseni) to reorient to find a corner in a rectangular tank with a distinctive featural cue (a blue wall). Then we tested fish after displacement of the feature on another adjacent wall. In the large enclosure, fish chose the two corners with the feature, and also tended to choose among them the one that maintained the correct arrangement of the featural cue with respect to geometric sense (i.e. left-right position). In contrast, in the small enclosure, fish chose both the two corners with the features and the corner, without any feature, that maintained the correct metric arrangement of the walls with respect to geometric sense. Possible reasons for species differences in the use of geometric and non-geometric information are discussed.  
  Address Department of General Psychology, University of Padua, Via Venezia, 8, 35131, Padova, Italy. valeriaanna.sovrano@unipd.it  
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  ISSN 1435-9448 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16794851 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2462  
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Author Quaranta, A.; Siniscalchi, M.; Vallortigara, G. url  doi
openurl 
  Title Asymmetric tail-wagging responses by dogs to different emotive stimuli Type Abstract
  Year (up) 2007 Publication Current biology : CB Abbreviated Journal Curr Biol  
  Volume 17 Issue 6 Pages R199-R201  
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  Publisher Cell Press Place of Publication Editor  
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  Series Volume Series Issue Edition  
  ISSN 0960-9822 ISBN Medium  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5733  
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Author Versace, E.; Morgante, M.; Pulina, G.; Vallortigara, G. url  doi
openurl 
  Title Behavioural lateralization in sheep (Ovis aries) Type Journal Article
  Year (up) 2007 Publication Behavioural Brain Research Abbreviated Journal Behav. Brain. Res.  
  Volume 184 Issue 1 Pages 72-80  
  Keywords Lateralization; Laterality; Brain asymmetry; Hemisphere; Sheep; Lamb; Strength of lateralization  
  Abstract This study investigates behavioural lateralization in sheep and lambs of different ages. A flock was tested in a task in which the animals were facing an obstacle and should avoid it on either the right or left side to rejoin flock-mates (adult sheep) or their mothers (lambs). A bias for avoiding the obstacle on the right side was observed, with lambs apparently being more lateralized than sheep. This right bias was tentatively associated with the left-hemifield laterality in familiar faces recognition which has been documented in this species. Differences between adult sheep and lambs were likely to be due to differences in social reinstatement motivation elicited by different stimuli (flock-mates or mothers) at different ages. Preferential use of the forelegs to step on a wood-board and direction of jaw movement during rumination was also tested in adult animals. No population bias nor individual-level lateralization was observed for use of the forelegs. At the same time, however, there was a large number of animals showing individual-level lateralization for the direction of jaw movement during rumination even though there was no population bias. These findings highlight that within the same species individual- and population-level lateralization can be observed in different tasks. Moreover, the results fit the general hypothesis that population-level asymmetries are more likely to occur in tasks that require social coordination among behaviourally asymmetric individuals.  
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  ISSN 0166-4328 ISBN Medium  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 6701  
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Author Ghirlanda, S.; Frasnelli, E.; Vallortigara, G. url  doi
openurl 
  Title Intraspecific competition and coordination in the evolution of lateralization Type Journal Article
  Year (up) 2009 Publication Philosophical Transactions of the Royal Society B: Biological Sciences Abbreviated Journal Phil. Trans. Biol. Sci.  
  Volume 364 Issue 1519 Pages 861-866  
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  Abstract Recent studies have revealed a variety of left–right asymmetries among vertebrates and invertebrates. In many species, left- and right-lateralized individuals coexist, but in unequal numbers (‘population-level’ lateralization). It has been argued that brain lateralization increases individual efficiency (e.g. avoiding unnecessary duplication of neural circuitry and reducing interference between functions), thus counteracting the ecological disadvantages of lateral biases in behaviour (making individual behaviour more predictable to other organisms). However, individual efficiency does not require a definite proportion of left- and right-lateralized individuals. Thus, such arguments do not explain population-level lateralization. We have previously shown that, in the context of prey–predator interactions, population-level lateralization can arise as an evolutionarily stable strategy when individually asymmetrical organisms must coordinate their behaviour with that of other asymmetrical organisms. Here, we extend our model showing that populations consisting of left- and right-lateralized individuals in unequal numbers can be evolutionarily stable, based solely on strategic factors arising from the balance between antagonistic (competitive) and synergistic (cooperative) interactions.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5346  
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