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Author Regolin, L.; Tommasi, L.; Vallortigara, G. doi  openurl
  Title Visual perception of biological motion in newly hatched chicks as revealed by an imprinting procedure Type Journal Article
  Year 2000 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 3 Issue 1 Pages 53-60  
  Keywords  
  Abstract Day-old chicks were exposed to point-light animation sequences depicting either a walking hen or a rotating cylinder. On a subsequent free-choice test (experiment 1) the chicks approached the novel stimulus, irrespective of this being the hen or the cylinder. In order to obtain equivalent local motion vectors, in experiments 2 and 3 newly hatched chicks were exposed either to a point-light animation sequence depicting a walking hen, or to a positionally scrambled walking hen (i.e. an animation in which exactly the same set of dots in motion as that employed for the walking hen was presented, but with spatially randomized starting positions). Chicks tested on day 1 (experiment 2) or on day 2 (i.e. after a period in the dark following exposure on day 1 (experiment 3)) proved able to discriminate the two animation sequences: males preferentially approached the novel stimulus, females the familiar one. These results indicate that discrimination was not based on local motion vectors, but rather on the temporally integrated motion sequence.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 3314  
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Author Vallortigara, G.; Regolin, L.; Rigoni, M.; Zanforlin, M. doi  openurl
  Title Delayed search for a concealed imprinted object in the domestic chick Type Journal Article
  Year 1998 Publication Animal Cognition Abbreviated Journal Anim. Cogn.  
  Volume 1 Issue 1 Pages 17-24  
  Keywords  
  Abstract Five-day-old chicks were accustomed to follow an imprinted object (a small red ball with which they had been reared) that was moving slowly in a large arena, until it disappeared behind an opaque screen. In experiments, each chick was initially confined in a transparent cage, from where it could see and track the ball while it moved towards, and then beyond, one of two screens. The screens could be either identical or differ in colour and pattern. Either immediately after the disappearance of the ball, or with a certain delay, the chick was released and allowed to search for its imprinted object behind either screen. The results showed that chicks took into account the directional cue provided by the ball movement and its concealment, up to a delay period of about 180 s, independently of the perceptual characteristics of the two screens. If an opaque partition was positioned in front of the transparent cage immediately after the ball had disappeared, so that, throughout the delay, neither the goal-object nor the two screens were visible, chicks were still capable of remembering and choosing the correct screen, though over a much shorter period of about 60 s. The results suggest that, at least in this precocial bird species, very young chicks can maintain some form of representation of the location where a social partner was last seen, and are also capable of continuously updating this representation so as to take into account successive displacements of the goal-object.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 3347  
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Author Sovrano, V.A.; Rainoldi, C.; Bisazza, A.; Vallortigara, G. url  openurl
  Title Roots of brain specializations: preferential left-eye use during mirror-image inspection in six species of teleost fish Type Journal Article
  Year 1999 Publication Behavioural Brain Research Abbreviated Journal Behav. Brain. Res.  
  Volume 106 Issue 1-2 Pages 175-180  
  Keywords Predator fixation; Fish; Left-eye preference  
  Abstract It has recently been reported that predator inspection is more likely to occur when a companion (i.e. the mirror image of the test animal) is visible on the left rather than on the right side of mosquitofish Gambusia holbrooki. This very unexpected outcome could be consistent with the hypothesis of a preferential use of the right eye during sustained fixation of a predator as well as of a preferential use of the left eye during fixation of conspecifics. We measured the time spent in monocular viewing during inspection of their own mirror images in females of six species of fish, belonging to different families--G. holbrooki, Xenotoca eiseni, Phoxinus phoxinus, Pterophyllum scalare, Xenopoecilus sarasinorum, and Trichogaster trichopterus. Results revealed a consistent left-eye preference during sustained fixation in all of the five species. Males of G. holbrooki, which do not normally show any social behaviour, did not exhibit any eye preferences during mirror-image inspection. We found, however, that they could be induced to manifest a left-eye preference, likewise females, if tested soon after capture, when some affiliative tendencies can be observed. These findings add to current evidence in a variety of vertebrate species for preferential involvement of structures located in the right side of the brain in response to the viewing of conspecifics.  
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  Area Expedition Conference  
  Notes Approved no  
  Call Number refbase @ user @ Serial 614  
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Author Siniscalchi, M.; Sasso, R.; Pepe, A.M.; Vallortigara, G.; Quaranta, A. url  doi
openurl 
  Title Dogs turn left to emotional stimuli Type Journal Article
  Year 2010 Publication Behavioural Brain Research Abbreviated Journal Behav. Brain. Res.  
  Volume 208 Issue 2 Pages 516-521  
  Keywords Dog; Laterality; Vision; Behaviour; Physiology; Cognition; Emotion; Animal welfare  
  Abstract During feeding behaviour, dogs were suddenly presented with 2D stimuli depicting the silhouette of a dog, a cat or a snake simultaneously into the left and right visual hemifields. A bias to turn the head towards the left rather than the right side was observed with the cat and snake stimulus but not with the dog stimulus. Latencies to react following stimulus presentation were lower for left than for right head turning, whereas times needed to resume feeding behaviour were higher after left rather than after right head turning. When stimuli were presented only to the left or right visual hemifields, dogs proved to be more responsive to left side presentation, irrespective of the type of stimulus. However, cat and snake stimuli produced shorter latencies to react and longer times to resume feeding following left rather than right monocular visual hemifield presentation. Results demonstrate striking lateralization in dogs, with the right side of the brain more responsive to threatening and alarming stimuli. Possible implications for animal welfare are discussed.  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0166-4328 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5080  
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Author Vallortigara, G.; Andrew, R.J. url  doi
openurl 
  Title Differential involvement of right and left hemisphere in individual recognition in the domestic chick Type Journal Article
  Year 1994 Publication Behavioural Processes Abbreviated Journal Behav. Process.  
  Volume 33 Issue 1-2 Pages 41-57  
  Keywords Right hemisphere; Left hemisphere; Domestic fowl; Lateralization; Chick  
  Abstract Right hemisphere advantage in individual recognition (as shown by differences between response to strangers and companions) is clear in the domestic chick. Chicks using the left eye (and so, thanks to the complete optic decussation, predominantly the right hemisphere) discriminate between stranger and companion. Chicks using the right eye discriminate less clearly or not at all. The ability of left eyed chicks to respond to differences between strangers and companions stimuli is associated with a more general ability to detect and respond to novelty: this difference between left and right eyed chicks also holds for stimuli which are not social partners. The right hemisphere also shows advantage in tasks with a spatial component (topographical learning; response to change in the spatial context of a stimulus) in the chick, as in humans. Similar specialisations of the two hemispheres are also revealed in tests which involve olfactory cues presented by social partners. The special properties of the left hemisphere are less well established in the chick. Evidence reviewed here suggests that it tends to respond to selected properties of a stimulus and to use them to assign it to a category; such assignment then allows an appropriate response. When exposed to an imprinting stimulus (visual or auditory) a chick begins by using right eye or ear (suggesting left hemisphere control), and then shifts to the left eye or ear (suggesting right hemisphere control), as exposure continues. The left hemisphere here is thus involved whilst behaviour is dominated by vigorous response to releasing stimuli presented by an object. Subsequent learning about the full detailed properties of the stimulus, which is crucial for individual recognition, may explain the shift to right hemisphere control after prolonged exposure to the social stimulus. There is a marked sex difference in choice tests: females tend to choose companions in tests where males choose strangers. It is possible that this difference is specifically caused by stronger motivation to sustain social contact in female chicks, for which there is extensive evidence. However, sex differences in response to change in familiar stimuli are also marked in tests which do not involve social partners. Finally, in both sexes there are two periods during development in which there age-dependent shifts in bias to use one or other hemisphere. These periods (days 3-5 and 8-11) coincide with two major changes in the social behaviour of chicks reared by a hen in a normal brood. It is argued that one function of these periods is to bring fully into play the hemisphere most appropriate to the type of response to, and learning about, social partners which is needed at particular points in development. Parallels are discussed between the involvement of lateralised processes in the recognition of social partners in chicks and humans.  
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  Series Volume Series Issue Edition  
  ISSN 0376-6357 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5341  
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Author Ghirlanda, S.; Vallortigara, G. url  doi
openurl 
  Title The evolution of brain lateralization: a game-theoretical analysis of population structure Type Journal Article
  Year 2004 Publication Proceedings of the Royal Society of London. Series B: Biological Sciences Abbreviated Journal  
  Volume 271 Issue 1541 Pages 853-857  
  Keywords  
  Abstract In recent years, it has become apparent that behavioural and brain lateralization at the population level is the rule rather than the exception among vertebrates. The study of these phenomena has so far been the province of neurology and neuropsychology. Here, we show how such research can be integrated with evolutionary biology to understand lateralization more fully. In particular, we address the fact that, within a species, left– and right–type individuals often occur in proportions different from one–half (e.g. hand use in humans). The traditional explanations offered for lateralization of brain function (that it may avoid unnecessary duplication of neural circuitry and reduce interference between functions) cannot account for this fact, because increased individual efficiency is unrelated to the alignment of lateralization at the population level. A further puzzle is that such an alignment may even be disadvantageous, as it makes individual behaviour more predictable to other organisms. Here, we show that alignment of the direction of behavioural asymmetries in a population can arise as an evolutionarily stable strategy when individual asymmetrical organisms must coordinate their behaviour with that of other asymmetrical organisms. Brain and behavioural lateralization, as we know it in humans and other vertebrates, may have evolved under basically ‘social’ selection pressures.  
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  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5345  
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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 2009 Publication Philosophical Transactions of the Royal Society B: Biological Sciences Abbreviated Journal Phil. Trans. Biol. Sci.  
  Volume 364 Issue 1519 Pages 861-866  
  Keywords  
  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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  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5346  
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Author Siniscalchi, M.; Sasso, R.; Pepe, A.M.; Dimatteo, S.; Vallortigara, G.; Quaranta, A. url  doi
openurl 
  Title Sniffing with the right nostril: lateralization of response to odour stimuli by dogs Type Journal Article
  Year Publication Animal Behaviour Abbreviated Journal Anim. Behav.  
  Volume In Press, Corrected Proof Issue Pages  
  Keywords animal welfare; Canis familiaris; dog; emotion; laterality olfaction; physiology  
  Abstract Lateralization in dogs, Canis familiaris, has been reported for paw usage and response to visual and acoustic stimuli. Surprisingly, however, no investigation of possible lateralization for the most relevant sensory domain of dogs, namely olfaction, has been carried out. Here we investigated left and right nostril use in dogs freely sniffing different emotive stimuli in unrestrained conditions. When sniffing novel nonaversive stimuli (food, lemon, vaginal secretion and cotton swab odours), dogs showed initial preferential use of the right nostril and then a shift towards use of the left nostril with repeated stimulus presentation. When sniffing arousal stimuli such as adrenaline and veterinary sweat odorants, dogs showed a consistent right nostril bias all over the series of stimulus presentations. Results suggest initial involvement of the right hemisphere in processing of novel stimuli followed by the left hemisphere taking charge of control of routine behaviour. Sustained right nostril response to arousal stimuli appears to be consistent with the idea that the sympathetic hypothalamic-pituitary-adrenal axis is mainly under the control of the right hemisphere. The implications of these findings for animal welfare are discussed.  
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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 5394  
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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 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.  
  Address (up)  
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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 Vallortigara, G.; Chiandetti, C.; Sovrano, V.A. url  doi
openurl 
  Title Brain asymmetry (animal) Type Journal Article
  Year 2011 Publication Wiley Interdisciplinary Reviews: Cognitive Science Abbreviated Journal WIREs Cogn Sci  
  Volume 2 Issue 2 Pages 146-157  
  Keywords  
  Abstract Once considered a uniquely human attribute, brain asymmetry has been proved to be ubiquitous among non-human animals. A synthetic review of evidence of animal lateralization in the motor, sensory, cognitive, and affective domains is provided, together with a discussion of its development and possible biological functions. It is argued that investigation of brain asymmetry in a comparative perspective may favor the link between classical neuropsychological studies and modern developmental and evolutionary biology approaches. WIREs Cogni Sci 2011 2 146–157 DOI: 10.1002/wcs.100 For further resources related to this article, please visit the WIREs website  
  Address (up)  
  Corporate Author Thesis  
  Publisher John Wiley & Sons, Inc. Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1939-5086 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number Equine Behaviour @ team @ Serial 5687  
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