Dissertationen zum Thema „Cognition in animals“

The mathematical abilities of animals have long fascinated scientists and the general public alike. However, it is only in the last two decades that researchers have systematically investigated this issue. Numerical abilities are widespread among mammals, birds and fish but little is known about their occurrence in other taxa. They play important functions in several ecological contexts, such as foraging, mate choice, and social interaction. The actual mechanisms underlying number sense in animals and the upper limits of these abilities are still a matter of debate. Conflicting results often emerge when comparing evidence from different species and studies of the same species. It is unclear to what extent this is due to differences in the complexity of the nervous system, to ecology, to phylogeny, or to other factors. Some have argued that intra- and inter-species differences may be due to differences in the used methodology. This is frequent in human literature, but the issue has received little attention in animals. To unravel these issues, we need to expand the number of studied species by including species that belong to a less studied taxa. In addition, there is a need for studies that directly compare different methodologies within the same laboratory. In this thesis, I focus on the two latter issues. In two studies, I investigated the effect of the used methodology on the assessment of numerical abilities in a small teleost fish, Poecilia reticulata. In the first study, I adopted an operant conditioning procedure to train fish to solve a numerical discrimination task using computer-generated stimuli. With this procedure, fish showed very low numerical discrimination performance, considerably lower than that reported in previous studies carried out in the same laboratory, in which fish had to solve a similar numerical task in a more naturalistic setting. In a series of subsequent experiments, I attempted to identify the key factors that determine the different outcome of the two methods. Results only partly answer the question and it is possible that there are non-cognitive factors (i.e. side bias due to cerebral lateralization) that explain the observed difference. Previous studies on guppies showed greater numerical acuity when tested with operant conditioning procedures than when tested with spontaneous preference methods, such as testing the preference for the larger of two social groups (shoal choice test). This difference could be due either to the different accuracy of the two methodologies or to within-species variation in acuity related to the examined context (foraging vs social). In the second study, I set up a modified version of the shoal choice test in order to eliminate some of the limitations of the method that are thought to determine a large imprecision in the measurement. With this new method, guppies were able to discriminate 4 vs. 5 companions, the same limit of numerical discrimination determined with operant conditioning procedures. The last two studies focused on studying numerical cognition in two new species, an amphibian (Hyla intermedia) and an arthropod (Acheta domesticus) in a new context, shelter choice. Both species showed a preference for the larger cluster of shelters and, in a series of subsequent experiments, I tried to determine the mechanism involved in such discrimination. H. intermedia appears to possess a genuine numerical system, being able to select the most numerous set even after I experimentally controlled the perceptual continuous variables, such as cumulative surface area and convex hull, that covary with number. Results suggest that A. domesticus have a less sophisticated system.
Studi empirici e teorici suggeriscono l'esistenza di un sistema per l’elaborazione di informazioni di quantità continue e discrete che si attiva in tutti i contesti che richiedono necessaria questa capacità (e.g., ricerca del cibo, scelta di un compagno). Poiché le caratteristiche di questo sistema sembrano simili tra le specie, alcuni autori hanno suggerito un’origine comune per questo sistema. Tuttavia, risultati contrastanti emergono quando confrontiamo le capacità numeriche tra diverse specie e persino nella stessa specie. In secondo luogo, la maggior parte degli studi si è concentrata su mammiferi, uccelli e pesci. Questo lavoro cerca di rispondere in parte a questi problemi. Nei primi due studi è stato investigato l’effetto della procedura utilizzata per valutare le capacità cognitive in una specie. Sono state indagate le abilità numeriche in guppy (Poecilia reticulata),ovvero un piccolo pesce d’acqua dolce, in un primo test basato su un comportamento spontaneo e un secondo test basato su un addestramento, utilizzando procedure modificate rispetto a lavori precedenti. Il primo esperimento è uno shoal choice test. In questa tipologia di esperimenti si sfrutta la naturale tendenza delle specie sociali, come guppy, ad unirsi in gruppi in situazioni di forte stress. Sono stati modificati alcuni aspetti delle vecchie procedure, confinando i soggetti all’interno di un cilindro trasparente al centro della vasca ed equidistante dagli stimoli. Sono stati studiati un confronto numerico di cui sappiamo che guppy è in grado di risolvere (3 vs. 4 pesci) e due confronti nei quali guppy fallivano secondo studi precedenti (4 vs. 6 e 4 vs. 5 pesci). I risultati hanno mostrato che, utilizzando una nuova procedura, guppy riesce a discriminare anche i confronti numerici più difficili che con le vecchie procedure non era stato possibile. Il secondo esperimento si basa su una classica procedura di addestramento. È stata sviluppata una nuova metodologia analoga a quelle già utilizzate per studiare le abilità numeriche in altri vertebrati: gli stimoli erano gruppi di pedine presentati da un monitor ed i soggetti erano addestrati a scegliere lo stimolo con maggior numerosità. Nonostante il problema cognitivo fosse lo stesso indagato in lavori precedenti, i soggetti hanno ottenuto risultati molto inferiori. Questi lavori ci suggeriscono che le procedure utilizzate possono fortemente influenzare le abilità numeriche di P. reticulata. Studi futuri sulle abilità numeriche e altre abilità cognitive dovrebbero focalizzarsi maggiormente sulle metodologie da adottare per poter confrontare i risultati tra le specie. Nei successivi due lavori, è stata indagata la capacità di discriminazione di quantità in specie finora poco studiate. Nello specifico, è stato condotto un primo lavoro su anfibi anuri (Hyla intermedia), ed un secondo su artropodi (Acheta Domesticus). I soggetti sono posti all’interno di un’ arena circolare di materiale plastico bianco uniformemente illuminata da una lampada posta in cima. Gli stimoli sono figure geometriche stampate su fogli A4 con lo scopo di simulare steli d’erba o rifugi in cui i soggetti possono ripararsi in una situazione pericolosa. Ogni soggetto è testato singolarmente in un unico test, in cui sono presentante coppie di stimoli contenenti un diverso numero di oggetti (quantità discrete) o stimoli di dimensioni diverse (quantità continue). Nel primo lavoro, le raganelle mostrano una preferenza spontanea per il gruppo contente il maggior numero di stimoli (quantità discrete) nei confronti 1 v s4 e 2 vs 4. Controllando la superficie cumulativa totale o lo spazio occupato nel confronto 2 vs 4, le raganelle mantengono la preferenza per lo stimolo più numeroso, suggerendo l’utilizzo di informazioni numeriche. Inoltre, le raganelle discriminano tra singoli stimoli con differente area (quantità continue), mostrando una preferenza per lo stimolo maggiore quando il rapporto tra le aree è 0.25. Successivi controlli hanno evidenziato come le raganelle utilizzano l’altezza e non la larghezza come caratteristica saliente nella discriminazione di quantità continue. Nel secondo lavoro, i grilli mostrano una preferenza per il gruppo contente il maggior numero di stimoli nei confronti 1 vs 4, 2 vs 4, e 2 vs 3. Pareggiando l’area totale degli stimoli nel confronto 2 vs 3, i grilli non mostrano una preferenza per lo stimolo maggiore. Nella discriminazione di quantità continue, i grilli preferiscono gli stimoli maggiori quando il rapporto delle aree è pari a 0.25; ed utilizzano la larghezza e non l’altezza come caratteristica principale degli stimoli. In conclusione, i lavori presentati in questa tesi mostrano come la metodologia utilizzata per indagare le capacità di cognizione numerica negli animali può influenzare i risultati trovati. Questo problema spiegherebbe parte della differenza riscontrata in letteratura tra le diverse specie e all’interno della stessa specie quando si utilizzano paradigmi differenti per valutarne le capacità di cognizione numerica. In secondo luogo, i due studi su anfibi ed invertebrati mostrano come i sistemi alla base della capacità di discriminazione di quantità siano presenti tra le diverse specie. Le differenze tra specie possono essere spiegate, in parte, dalla metodologia utilizzata per valutarle, oppure dalla differenza del sistema percettivo in queste specie. Sono necessari futuri studi su specie poco studiate e nuovi contesti per poter comprendere l’origine e l’evoluzione della cognizione numerica.

Bibliography: leaves 263-278. This research investigated the existence of individual differences in cognitive abilities in mice. Arguments have been put forward regarding the likely bases of such differences.

Thesis (Ph.D)--Psychology, Georgia Institute of Technology, 2009.
Committee Chair: Maple, Terry; Committee Member: Blanchard-Fields, Fredda; Committee Member: Hampton, Robert; Committee Member: Marr, Marcus; Committee Member: Stoinski, Tara. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Research as to how humans group natural kinds, such as animals, is essential to understanding categorization processes. However, it lacks conventional application and generalization to everyday life. Humans are social beings that encounter a wide array of individuals on a daily basis. In these situations, we are required to consider various properties that make up these people. As Keller (2005) suggests, the way we categorize is shaped by our theories about the world. Therefore, when we determine the rationale behind people’s social categorization processes, we are better able to understand people’s perceptions of their social environment. Moreover, when we conduct scientific research on how people categorize race, we gain substantial information about their perceptions and understanding of race. Thus, the goal of the present study was to determine how and to what extent people categorize race and if they use the principles of psychological essentialism to do so. In order to determine if people tend to essentialize race in a similar manner as other natural kinds, the third study of the Hampton, Estes, Simmons (2007) research was replicated. In Study 1 and Study 2, undergraduate participants were obtained from Western Kentucky University’s psychology study board. In Study 1, participants were presented with transformation stories in which an animal or person came to look and act like another animal or person as a result of either mutation or maturation. Approximately one-half of the participants received scenarios that included information about the exemplar’s offspring. Approximately one-half received scenarios that excluded this information. Additional transformation stories that described changes to artifacts and the body (i.e. weight and hair length) were added as filler items. Participants rated the artifact/animal/person’s typicality, category membership, and their level of confidence in their ratings. In addition, they provided justifications for their responses. In Study 2, transformations were described as being the result of unintended or intended changes. In Study 2, one-half of the scenarios included a statement that the animal or human’s offspring resembled the initial state, I. One-half of the scenarios included a statement that the animal or human’s offspring resembled the final state, F. Participants rated the artifact/animal/person’s typicality and category membership. They were also asked to provide justifications for their responses. This study provides further support for the belief of race as a natural kind given that subjects were more likely to essentialize race than animals. The study also suggests that people view race differently than other factors related to appearance (i.e. hair length and weight). In both studies, the majority of subjects were willing to state that a person changed if their hair or weight changed; however, they were unwilling to indicate a person could change their race. Furthermore, the justification data obtained in the study was one of the first studies to differentiate the reasoning used by those who did and did not essentialize animals and race.

By investigating the cognitive capacities of non-human primates, we can begin to understand the cognitive capacities of the evolutionary ancestors we share with these species. While there is a great deal of research exploring the socio-cognitive abilities of simian primates, prosimians have not been sufficiently studied. Without data from these species, our knowledge about the evolution of the primate mind is limited to the common ancestor shared between simian primates only, precluding understanding of the phylogenetic origins of certain phenomena. I explored the socio-cognitive capacities of lemurs, a type of prosimian primate. I studied several areas of social cognition related to social referencing, defined as the ability to use and seek out social information when appraising objects or events. As social referencing is a popular subject in both human developmental and non-human primate literature, I aimed to determine how prosimians’ capacities compare. My research was conducted with captive lemurs of three species: Eulemur fulvus fulvus, Eulemur macaco macaco, and Eulemur fulvus rufus. I found that lemurs use social cues regarding food palatability to modify their own feeding behaviour and that they visually attend to conspecifics differently when presented with novel, as compared to familiar, foods. Lemurs also visually referred to a human experimenter’s face when presented with an anomalous interaction and went on to engage in gaze alternation. Lemurs failed to use information about the experimenter’s attentional state, however, when modifying their use of a trained gesture. Finally, I found that lemurs are able to visually co-orient with conspecifics, correctly prioritising information from the head over that from the body, and that they go on to use conspecific gaze to locate hidden resources. These results show that lemurs are more cognitively advanced than previously thought and the origins of some social referencing skills may be phylogenetically older than previously hypothesised.

Society’s current experience of nature is ambiguous. Just as nature proves severely affected by human activities and vulnerable, it also appears threatening to us. Although the changes in nature have been perceived for long as an ecological crisis, this experience and the challenges it provides have remained persistently exigent over the last four decades. As a consequence, our epistemological understanding of nature and culture as separate entities has been inherently shaken. My study is located among ecocritical attempts to negotiate these experiences. Immanent critiques of E. O. Wilson’s and Bruno Latour’s epistemologies exemplify how we cannot escape the dualism in society’s relationship to nature by simply declaring nature’s and culture’s unity. Relying on the social philosophy of Max Horkheimer and Theodor W. Adorno, I instead consider the dualism as historically both true and false, and argue that instrumental reason provides a socio-psychological barrier to transcending the way Western society relates to nature. Central to the situation’s perpetuation is the confidence that the object of knowledge can be adequately and steadily identified in knowledge. Based on Adorno’s negative dialectics, I develop a model of cognition that works through the dualism within the knowing subject and in its relation to animals. This model is substantiated in the context of Enlightenment thought. A reconstruction of the development of René Descartes’ (1596–1650) epistemology in relation to his philosophy of nature and the place of animals within it shows the animal as particularly resistant to Descartes’ conceptual identification. In the writings on animal behaviour of Hermann Samuel Reimarus (1694–1768) this resistance further manifests as a self-mediation of animals, which denotes the limits to their conceptual assimilation. Maria Sibylla Merian’s (1647–1717) aesthetically mediated insect studies capture this tension between species commonalities and unique particularities, and represent the single specimens as nonidentical individuals. Through critical engagement with these works, my study develops a cognitive approach to nature that preserves its object as qualitatively mediated between universal and particular properties, and inherently nonidentical. Simultaneously, it recovers the animal as an object of knowledge particularly resistant to identificatory thought. Consolidating these two insights, aesthetic mediation of animals provides an experience that reveals to the subject its limited power over the objects and which is capable of raising the memory of nature within the subject.

Nest building in birds has long been assumed to be a behaviour that is not learned, despite suggestive evidence to the contrary. In this thesis I investigated the role of learning in nest building in birds. I focused primarily on the choice of nest material made by zebra finches, in particular between two or more colours of nesting material. Using this aspect of behaviour, I found that adult nest building birds changed their preference for a particular colour of nesting material depending on their own nesting and breeding experience: males that built a nest using material of their less preferred colour later preferred that colour following a successful breeding attempt in that nest. In contrast to this role for learning in adults, in two other experiments I found no evidence that juvenile birds learned about the nest from which they had fledged or that birds learned about what material to nest with from conspecifics. Using wild Southern masked weavers, I also addressed variability in a particular aspect of nest building: the attachment of the very first blade of grass knotted onto a branch. I found that birds did not construct the same attachment each time they did it, even when building at the same location, but that males generally used more loops in their attachments as they built more nests, and when using longer pieces of grass. Finally, I tested zebra finches on a nest building ‘task', using a paradigm often used to test cognitive abilities among tool-users. Birds were presented with two lengths of nest material, one of which was more appropriate for one of two sizes of nest box entrance. I found that nesting birds could choose the appropriate length of material and that the birds' handling of material and their choice of material changed with experience. Taking these results together, it seems that there is a greater role for learning in nest construction than is generally acknowledged and that nest building might involve the same underlying cognitive processes as tool manufacture and use.

Elephants' complex societies, well-developed communication systems, evolutionary history and close working relationship with humans make them an important species for studies of cognition but research on elephant cognition is sparse. In this thesis I aim to illuminate the social cognition involved in the interpretation and production of visual signals by African elephants (Loxodonta africana). My results are intended to contribute to the cross-species literature on social cognition and help to elucidate wild elephant social behaviour. I studied captive elephants, housed at an elephant-back safari company in Victoria Falls, and wild elephants in Hwange National Park, both in Zimbabwe. Wild elephants display a vast array of postures, actions and signals. I found that elephants recognise visual attentiveness in others when they signal silently, producing more signals when their audience can see them, and using the body and face orientation of an audience to judge their attention. When responding to typically human visual signals, elephants immediately responded correctly to deictic gestures, including variants of pointing that they were unlikely to have already experienced. These results indicate elephants' astonishing sensitivity to even subtle social cues. I found no indication that elephants reason about mental states such as false beliefs, or rationality; however, limitations of the experimental design meant I was unlikely to find such an ability even if it is present in elephants. Furthermore, I discovered that elephants have a form of referential indication in their natural communication in the wild. Elephants match their direction of attention with a type of trunk action produced by a group member. Attending to human-like signals, and interpreting them as communicative is an advantage for any animal working with humans and that ability might explain the choice of species that are ancestors of today's domestic animals.

The social transmission of social behaviours in nonhuman primates has been understudied, experimentally, relative to instrumental, food-related behaviours. This is disproportional in relation to the comparatively high percentage of potential social traditions reported in wild primates. I report a systematic survey of the social learning literature and provide quantitative evidence of the discrepancy (Watson and Caldwell, 2009). Addressing the identified deficit in experimental work on social behaviours, I also report three empirical studies investigating the contagious nature of affective states in captive, socially housed marmosets. I carried out an observational study, to determine whether marmosets are influenced by spontaneously produced neighbour calls to perform a range of behaviours associated with similar affect. My results supported a neighbour effect for anxiety in marmosets. Consistent with previous findings for chimpanzees (Baker and Aureli, 1996; Videan et al., 2005), I also found evidence for neighbour effects for aggression and affiliation (Watson and Caldwell, 2010). Through experimental playback, I investigated contingent social contagion in the auditory and visual modalities. The playback of pre-recorded affiliative (chirp) calls was found to be associated with marmosets spending increased time in a range of affiliative behaviours. Playback of video showing conspecifics engaged in a positive affiliative behaviour (allogrooming) also appeared to cause marmosets to spend longer performing various affiliative behaviours. My results indicate that social contagion of affiliation is a multi-modal phenomenon in marmosets and also represent the first evidence that allogrooming is visually contagious in primates. Sapolsky (2006) conceptualised culture as the performance of species-typical behaviours to an unusual extent, termed ‘social culture’. Researchers have yet to directly investigate a transmission mechanism. I investigated whether a social culture of increased affiliation could be initiated in marmosets through the long-term playback, of positive calls, or of video of positive behaviour. The results were consistent with a relatively long-lasting influence of the playback of affiliative calls across several affiliative behaviours. The effect appeared to last substantially beyond the specific hours of playback, between playbacks, and after playback had ceased, potentially indicating a temporary shift in social culture. These results are preliminary but provide some support for the proposal that auditory social contagion may be a transmission mechanism for social culture. The long-term video playback of allogrooming appeared to result in a transitory shift in performance of the identical behaviour (increased allogrooming) after playbacks had ceased. In addition to theoretical implications for social cognition and social culture, my findings have potential practical application for the enhancement of welfare in captive marmosets through sensory, and non-contact social, enrichment.

Many animals socially learn, but very few do so through teaching, where an individual modifies its behaviour in order to facilitate learning for another individual. Teaching behaviour is costly, but can confer numerous advantages, such as high fidelity transmission of information or an increase in the rate of social learning. In many putative cases of teaching, it is not known whether the pupil learns from the modified behaviour. This thesis addresses this issue in three cases of potential teaching behaviour. In particular, it investigates whether the role of food transfers in wild golden lion tamarins is to teach which foods are good to eat (Chapter 5). There was little evidence that novel foods were transferred more than familiar foods, and this was not due to the juveniles attempting to obtain novel foods more than familiar ones, or by adults discarding novel foods more than familiar ones. Transfers were however more successful when donors had previously ingested the food type transferred. Successful food transfers also had a positive correlation with foraging choices once juveniles were older, suggesting they learned from food transfers. In golden lion tamarins, this thesis also examined whether juveniles learned from food-offering calls which substrates were good to forage on (Chapter 6). Juveniles that experienced playback of food-offering calls ate more on a novel substrate, than juveniles that did not experience those playbacks, both immediately as the calls were being played, and in the long term, six months after the playbacks. This suggests that juveniles learned from the playbacks. Finally, this thesis attempted to replicate previous findings showing that hens modify their behaviour when chicks feed from seemingly unpalatable food, and explored whether chicks learned what food to eat based on the maternal display (Chapter 7). The experiment failed to find evidence for teaching behaviour, but results were not inconsistent with previous findings. Moreover, there was little evidence that chicks learned from their mother, quite to the contrary, hens seemed to acquire their foraging decisions based on their chicks' choices.

Thesis (M.A.)--Georgia State University, 2007.
Title from file title page. David A. Washburn, committee chair; Eric Vanman, Michael J. Beran, Heather Kleider, committee members. Electronic text (76 p. : col. ill.) : digital, PDF file. Description based on contents viewed Mar. 25, 2008. Includes bibliographical references (p. 71-76).

Decision making is a framework we impose on a vast universe of possible behaviors to better understand the advantages and disadvantages of acting in different ways. Decisions under uncertainty are of particular interest because stochasticity is a feature of environments both today and throughout evolutionary history. As a result, we might expect decision makers (DMs) to have evolved mechanisms to handle variability. In this dissertation, I examine common decision processes in several model species: European starlings (Sturnus vulgaris), Banded tetras (Astyanax fasciatus) and humans (Homo sapiens). The broad range of approaches discussed include currencies DMs are expected to maximize (Risk Sensitivity Theory, Expected Utility), the currencies DMs do maximize (e.g. long versus short term rate maximizing models), the representation of outcomes in memory (Scalar Expectancy Theory) as well as explicit choice mechanisms (Sequential Choice Model). The first section of this thesis discusses responses to risk, offering humans and starlings choices between options which deliver certain or variable outcomes. Starlings demonstrate sensitivity to changes in the probability of variable outcomes and strong support for local rate maximization. Humans appear similarly sensitive to their own accuracy when task difficulty is varied. When the DM’s affective state was manipulated, neither humans nor starlings exhibit changes in risk preferences, but the effectiveness of these manipulations used could not be confirmed. Another topic of inquiry is the effect of the DM’s state at the time of valuation learning. State dependent valuation learning is demonstrated for the first time in a fish species, but Within Trial Contrast is not observed in starlings. Lastly, two experiments find strong support for the Sequential Choice Model, a promising new model of the mechanism of choice. Taken together, these experiments offer a glimpse into shared decision processes, but leave open questions about the mechanisms through which value is acquired.

A full understanding of any biological trait requires investigation of its evolutionary origin. Primates inspire great curiosity amongst researchers due to the remarkable diversity across species in both anatomical and behavioural traits, including sociality, sexual behaviour, life histories, neuro-anatomy, cognitive abilities and behavioural repertoires. The study of primates has involved comparative approaches since its inception, however, the necessary tools for statistically investigating the macro-evolutionary processes responsible for current diversity in biological traits have been developed only in the last 30 years or so, namely phylogenetic reconstruction and phylogenetic comparative methods. Amongst a multitude of evolutionary questions that can be addressed by phylogenetic comparative analyses, this thesis attempts to address two in particular, concerning primates. First, chapters 3 and 4 use meta-analysis and phylogenetic comparative analyses to investigate the evolution of large, brightly coloured ‘exaggerated sexual swellings' in female Catarrhine (‘Old World') primates. Together, chapters 3 and 4 show that such swellings are signals of temporal fertility, and present evidence to suggest that swellings co-evolved with conditions favouring male mate choice and cryptic female choice, therefore shedding light on the general conditions under which female signals of temporal fertility should evolve. Second, chapters 5 and 6 use phylogenetic comparative analyses investigate the evolution of enlarged brain size in the primate order. Together, chapters 5 and 6 suggest that multiple selection pressures have contributed to diversity in brain size and cognitive traits across primates, including sociality, intra-sexual competition and extended life history. Further, analyses presented in chapter 6 suggest that reliance on learned behaviour is a self-reinforcing evolutionary process, favouring ‘runaway' increases in cognitive abilities and reliance on culture in some primate lineages, which parallels increases in brain size, cognitive ability and reliance on culture in human evolution.

An important element in understanding the evolutionary origin of human language is to explore homologous traits in cognition and communication between primates and humans (Burling, 1993, Hewes, 1973). One proposed modality of language evolution is that of gestural communication, defined as communicative movements of hands without using or touching objects (de Waal, 2003). While homologies between primate calls and language have been relatively well explored, we still have a limited understanding of how cognitive abilities may have shaped the characteristics of primate gestures (Corballis, 2003). Chimpanzees (Pan troglodytes) are our closest living relatives and display some complex cognitive skills in various aspects of their gestural behaviour in captivity (de Waal, 2003, Pollick and de Waal, 2007). However, it is not yet currently clear to what extent these abilities seen in captive apes are typical of chimpanzees in general and to what extent cognitive capacities observed in captive chimpanzees have been enhanced by the socio-cultural environment of captivity such as language training. In this Ph.D. research, I investigated the cognitive skills underlying gestural communication in both wild and language trained chimpanzees, with a special focus on the repertoire and the intentionality of production and comprehension. The study of cognitive skills underlying the production of the repertoire and the role of intentionality is important because these skills are cognitively demanding and are a prerequisite in human infants for their ability to acquire language (Baldwin, 1995, Olson, 1993). My research suggests that chimpanzee gestural communication is cognitively complex and may be homologous with the cognitive skills evident in pre-verbal infants on the cusp of language acquisition. Chimpanzees display a multifaceted and complex signal repertoire of manual gestures. These gestures are the prototypes, within which there is variation, and between which the boundaries are not clear-cut, but there is gradation apparent along several morphological components. Both wild and language trained chimpanzees communicate intentionally about their perceived desires and the actions that they want the recipients to undertake. They do not just express their emotions, but they communicate flexibly by adjusting their communicative tactics in response to the comprehension states of the recipient. Whilst chimpanzees communicate their intentions flexibly, the messages conveyed are specific. However, recipients comprehend gestures flexibly in light of the signaller’s overall intentions. Whilst wild and language trained chimpanzee gestural communication revealed similar cognitive characteristics, language trained chimpanzees outperformed wild apes in that they had ability to use signals which made distinctions that human deictic words can make. Whilst these differences between wild and language trained chimpanzees may be due to the different methodological approaches used, it is conceivable that language training may have influenced captive ape cognitive skills in the representational domain. These results from wild and language trained chimpanzees indicate that chimpanzees possess some form of cognitive skills necessary for language development and that cognitive skills underlying repertoire and use in chimpanzees are a shared capacity between humans, other apes and a common ancestor. These findings render theories of the gestural origins of language more plausible. Related publications: 1. Roberts, A. I., Vick, S.-J., Roberts, S. G. B., Buchanan-Smith, H. M. & Zuberbühler, K. 2012. A structure-based repertoire of manual gestures in wild chimpanzees: Statistical analyses of a graded communication system. Evolution and Human Behavior, Published online: http://dx.doi.org/ 10.1016/j.evolhumbehav.2012.05.006 2. Roberts, A. I., Vick, S.-J. & Buchanan-Smith, H. 2012. Usage and comprehension of manual gestures in wild chimpanzees. Animal Behaviour, Published online: http://dx.doi.org/10.1016/j.anbehav.2012.05.022

Thesis (Ph. D.)--Georgia State University, 2006.
David A. Washburn , committee chair; Claudio C. Cantalupo, Eric J. Vanman, Duane M. Rumbaugh, committee members. Electronic text (102 p. : col. ill.)) : digital, PDF file. Description based on contents viewed July 13, 2007. Includes bibliographical references (p. 79-96).

Gibbons (Hylobatidae), taxonomically apes, have been largely ignored in cognitive research. This is surprising given their unique phylogenetic position, being intermediate between the monkeys and great apes, and the available diversity of extant species. They are therefore, ideally placed to study the evolution of cognitive abilities in the hominoid line; they offer the opportunity to determine how the mental capacities of primates have changed through the transition from monkey to ape. This research aimed to begin to fill the void in our knowledge regarding the cognitive abilities of this family through investigations of their object manipulation and tool-use skills, relating the findings to the evolution of the hominoid brain. In a raking-in task, where the gibbons were presented with a tool that could be used to draw in an out-of-reach food item, these apes evidenced potentially insightful comprehension of object relationships when the tool and goal object were presented in direct alignment. They also proficiently used a rake to retrieve a reward while avoiding a trap that presented an impediment to goal attainment; however, in general, they required a period of learning to perform consistently. Once the necessary relationships between the tool and goal object were not physically situated in the task layout, as in true tool-use manipulation, the gibbons performed poorly. In a raking-in task where the necessary orientation for success had to be produced by the subject, no individual evidenced foresightful comprehension of the required action. There was some suggestion of learning the correct behaviour through associative processes. This finding was also supported by evidence from dipping experiments where the gibbons were provided with a transparent box containing a liquid reward and sticks that could be used as tools to access it. No individual developed dipping behaviour. The gibbons therefore, performed well on tasks when the salient relationships between tool and goal were directly perceivable. Once they became responsible for producing that relationship, performance was poor. When the necessary orientation between the tool and goal was not provided by the experimenter, the gibbons evidenced low motivation to manipulate the objects. Given the gibbons’ requirement for direct visual feedback to comprehend the causal interactions between objects, this likely hindered their learning process. Failure therefore on the true tool-use tasks may not represent a particular cognitive limitation in these apes. A consistent finding was that the hoolock gibbons (Bunopithecus) were the most attentive and effective of the four gibbon genera. This is potentially due to the more variable natural environment experienced by these apes, driving selection for greater exploratory tendencies and flexibility of behaviour. The findings from this, and other work on primate cognition, suggest that contrary to propositions put forward by proponents of modular accounts of hominid brain evolution, the cognitive architecture of non-human primates contains neural mechanisms capable of processing technical information that may not be completely encapsulated. Suggestions that no non-human possesses specialised cognitive machinery for understanding objects as tools are also challenged.

While most human language is expressed verbally, the gestures produced concurrent to speech provide additional information, help listeners interpret meaning, and provide insight into the cognitive processes of the speaker. Several theories have suggested that gesture played an important, possibly central, role in the evolution of language. Great apes have been shown to use gestures flexibly in different situations and to modify their gestures in response to changing contexts. However, it has not previously been determined whether ape gestures are defined by structural variables, carry meaning, are used to intentionally communicate specific information to others, or can be used strategically to overcome miscommunication. To investigate these questions, I studied three captive populations of orangutans (Pongo pygmaeus and P. abelii) in European zoos for 10 months. Sixty-four different gestures, defined through similarities in structure and use, were included in the study after meeting strict criteria for intentional usage. More than half of the gesture types were found to coincide frequently with specific goals of signallers, and were accordingly identified as having meanings. Both structural and social variables were found to determine gesture meaning. The recipient’s gaze in both the present and the past, and the recipient’s apparent understanding of the signaller’s gestures, affected the strategies orangutans employed in their attempts to communicate when confronted with different types of communicative failure (e.g. not seeing, ignoring, misunderstanding, or rejecting a gesture). Maternal influence affected the object-directed behaviour and gestures of infants, who shared more gestures with their mothers than with other females. These findings demonstrate that gesture can be used as a medium to investigate not only the communication but also the cognition of great apes, and indicate that orangutans are more sensitive to the perceptions and knowledge states of others than previously thought.

Understanding intentionality, i.e. coding the object directedness of agents towards objects, is a fundamental component of Theory of Mind abilities. Yet it is unclear how it is perceived and coded in different species. In this thesis, we present a series of comparative studies to explore human adults' and Capuchin monkeys' ability to infer intentional objects from actions. First we studied whether capuchin monkeys and adult humans infer a potential object from observing an object-directed action. With no direct information about the goal-object, neither species inferred the object from the action. However, when the object was revealed, the monkeys retrospectively encoded the directedness of the object-directed action; unexpectedly, in an adapted version of the task adult humans did not show a similar ability. We then adapted another paradigm, originally designed by Kovács et al (2010), to examine whether the two species implicitly register the intentional relation between an agent and an object. We manipulated an animated agent and the participants' belief about a ball's presence behind a hiding screen. We found no evidence showing that humans or monkeys coded object-directedness or belief. More importantly, we failed to replicate the original results from Kovács et al's study, and through a series of follow up studies, we questioned their conclusions regarding implicit ToM understanding. We suggested that, instead of implicit ToM, results like Kovacs et al's might be interpreted as driven by “sub-mentalizing” processes, as suggested by Heyes (2014). We conclude that so called ‘implicit ToM' may be based upon the computation of intentional relations between perceived agents and objects. But, these computations might present limitations, and some results attributed to implicit ToM may in fact reflect “sub-mentalizing” processes.

Bakalauro darbe siekiama ištirti pradinių klasių mokinių, turinčių didelių ir labai didelių specialiųjų ugdymosi poreikių, pasiekimus naminių gyvulių pažinimo srityje. Tyrime dalyvavo pradinių lavinamųjų klasių mokiniai, kuriems nustatytas vidutinis ir žymus intelekto sutrikimas. Interviu dalyvavo pedagogai, ugdantys mokinius, turinčius didelių ir labai didelių specialiųjų ugdymosi poreikių. Iš viso apklausti 30 mokinių ir 6 pedagogai. Buvo parengtas tyrimo instrumentas – klausimynas. Individualia anketine apklausa siekta atskleisti mokinių požiūrį į naminius gyvulius, turimas gamtamokslines žinias ir supratimą apie juos. Norėta ištirti, kokias mokiniai turi vertybines nuostatas naminių gyvulių atžvilgiu, pateikiant klausimus apie mokinių elgesį su artimiausioje aplinkoje esančiais gyvūnais. Tyrinėtas ugdytinių gebėjimas išvardinti naminių gyvulių pavadinimus (pagal sąvoką Naminiai gyvuliai), gebėjimas pamėgdžioti jų skleidžiamus garsus (pagal pateiktą pavadinimą), mokėjimas pavadinti naminius gyvulius apibendrinančiu žodžiu. Siekta sužinoti, koks mokinių supratimas apie naminių gyvulių sandarą (prašant parodyti ir pavadinti kūno dalis) ir funkcijas, poreikius bei svarbą žmogui. Gauti rezultatai parodė, kad dauguma pradinių klasių mokinių, turinčių didelių ir labai didelių specialiųjų ugdymosi poreikių, vardina pagal duotą sąvoką 1-3 naminių gyvulių pavadinimus; paveikslėliuose geriausiai atpažįsta ir pavadina katę ir šunį, karvę, arklį bei kiaulę. Didžioji dalis ugdytinių... [toliau žr. visą tekstą]
The Bachelor's paper aims at examination of the achievements of primary school pupils with severe and very severe educational needs in the field of domestic animal cognition. Pupils of primary school with established average and significant intellectual disabilities participated in the research.. Educators teaching the pupils with severe and very severe special educational needs participated in an interview. In total, 30 pupils and 6 educators have been interviewed. We have prepared a research instrument - a questionnaire. By means of an individual questionnaire survey, we aimed to reveal the attitude of the pupils towards domestic animals, their knowledge available of the natural sciences and their awareness of them. The aim is to investigate what moral values the pupils have in respect of domestic animals by giving questions about the behaviour of the pupils with the animals in their immediate environment. We have investigated an ability of the pupils to list the names of domestic animals (under a concept of Domestic Animals), their ability to imitate their sounds (according to a given name), and their skills to name the domestic animals by a generalising word. We aimed at finding out what is the pupils' understanding of the structure of the domestic animals (by asking to show and name their body parts) ) and the functions, as well as their importance for people. The obtained results have shown that the majority of the primary school pupils with severe and very severe... [to full text]

In this thesis, I explore two subjects of importance to the study of cultural evolution and cumulative culture; behavioural flexibility in chimpanzees, and social transmission in human children. In Chapter 1, I give an overview of current literature on the cognitive requirements of cumulative culture, with a focus on behavioural flexibility as a capacity which facilitates cumulative culture. I also explore a current discussion in the field of cultural evolution; namely the debate between "standard" and cultural attraction-based approaches to the study of cultural evolution. Chapter 2 is an experimental investigation of the capacity of chimpanzees to respond flexibly to a changing foraging task. This study found that chimpanzees did alter their behaviour, but to a limited degree. In Chapter 3 I provide the same artificial foraging task to two further groups of chimpanzees, at a sanctuary in Zambia. This study again found that chimpanzees altered their behaviour in response to task constraints, but also found a significant difference in performance between the two groups tested. Chapter 4 explores one potential factor which may contribute to these group differences; social tolerance. Data on social tolerance from all three groups of chimpanzees is presented. In Chapter 5, I turn to another key factor in the study of culture and also address the cultural attraction approach, by conducting a transmission chain study of four- to eight-year-old human children, comparing the transmission of a symbolic and non-symbolic image. I found that neither image was reliably transmitted along transmission chains. Finally, in Chapter 6, I discuss the findings of the thesis, and suggest that future work considers multiple demographic groups, whether this means the inclusion of multiple groups of apes in studies of non-human primate cognition, or the consideration of how cultural behaviours might be transformed when transmitted by human children rather than adults.

Cumulative culture is rare, if not altogether absent in non-human species. At the foundation of cumulative learning is the ability to flexibly modify, relinquish or build upon prior behaviours to make them more productive or efficient. Within the primate literature, a failure to optimise solutions in this way is often proposed to derive from low-fidelity copying of witnessed behaviours, sub-optimal social learning heuristics, or a lack of relevant socio-cognitive adaptations. However, humans can also be markedly inflexible in their behaviours, perseverating with, or becoming fixated on outdated or inappropriate responses. Humans show differential patterns of flexibility as a function of cognitive load, exhibiting difficulties with inhibiting suboptimal behaviours when there are high demands on working memory. Here I present a series of studies on captive chimpanzees which show that not only is inhibitory control compromised in chimpanzees, but indicate ape behavioural conservatism may be underlain by similar constraints as in humans; chimpanzees show relatively little conservatism when behavioural optimisation involves the inhibition of a well-established but simple solution, or the addition of a simple modification to a well-established but complex solution. In contrast, when behavioural optimisation involves the inhibition of a well-established but complex solution, and especially when the alternative solution is also complex, chimpanzees show evidence of behavioural conservatism. I propose that conservatism is linked to behavioural complexity, potentially mediated by cognitive resource availability, and may be an important factor in the evolution of cumulative culture.

Culture is an important means by which both human and non-human animals transmit useful behaviours between individuals and generations. Amongst animals, chimpanzees live particularly varied cultural lives. However, the processes and factors that influence whether chimpanzees will be motivated to copy an observed behaviour are poorly understood. In this thesis, I explore various factors and their influence on social learning decisions in chimpanzees. In turn, the chapters examine the influence of (i) rank-bias towards copying dominant individuals, (ii) majority and contextual influences and finally (iii) individual differences in proclivity for social learning. In my first experiment, I found evidence that chimpanzees are highly motivated to copy the behaviour of subordinate demonstrators and innovators in an open-diffusion puzzle-box paradigm. In contrast, behaviours seeded by dominant individuals were not transmitted as faithfully. This finding has important implications for our understanding of the emergence of novel traditions. In my second experiment, I found that some chimpanzees are highly motivated to relinquish an existing behaviour to adopt an equally rewarding alternative if it is consistently demonstrated by just one or two individuals within a group context, but not in a dyadic context. This contrasts with prior studies which argue that chimpanzees are highly conservative and may hint at a hitherto unrecognised process by which conformity-like behaviour might occur. Finally, I performed a novel type of ‘meta' analysis on 16 social learning studies carried out at our research site to determine whether individuals demonstrated consistency in their social learning behaviour across experimental contexts. Strong evidence for individual differences in social information use was found, with females more likely to use social information than males. No effect of age, research experience or rearing history was found. This presents a promising new method of studying individual differences in behaviour using the accumulated findings of previous work at a study site.

Finding food in tropical forests poses a potentially major problem for chimpanzees, whose ranging is thought primarily to be directed at locating suitable food resources: (1) chimpanzees are frugivorous, large bodied and live in large home ranges; (2) they lack specialised sensory or locomotor abilities, and terrestrial travel is known to be costly; but (3) fruits are randomly distributed in space and time. Evidence from studies of captive individuals suggests chimpanzees are capable of remembering the locations of out of sight resources and can compute least distance routes to these resources, but whether this ability translates to the natural foraging behaviour of wild chimpanzees has never been investigated. My observational study was designed to assess how the chimpanzees (Pan troglodytes schweinfurthii) of Budongo Forest, Uganda, locate these patchy resources. I mapped the routes of 14 focal individuals over a 12-month period. I considered how these foraging routes were structured by breaking the path into segments of travel between resources. Consecutive segments of travel between resources were found not to be independent, but assembled into "super-segments" that take in a number of resources along one trajectory. These super-segments are not necessarily directed towards feeding resources, however: travel is not always food directed. Comparisons of actual chimpanzee routes with randomly generated simulations suggest most individuals do not attempt to minimise their travel distances. There is evidence to suggest energetically stressed individuals can remember the locations of recently visited food resources and return to these patches in order to minimise travel distances when necessary, but overall, food is not difficult to find for this community of chimpanzees. I propose this is because males defend a territory with super-abundant food resources, meaning availability is not a limiting factor of foraging. Male chimpanzees can be characterised as convenience feeders, taking food whilst satisfying other, social needs.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Para se ajustar a mudanças ambientais, os animais podem aprender sobre tais variações e modular seu comportamento de acordo com suas necessidades. Em alguns casos, no entanto, mudanças no ambiente social ou físico podem gerar estados de medo que levam a respostas de estresse fisiológico e que podem modificar a capacidade de um indivíduo em aprender, impactando negativamente o bem-estar desse animal. O isolamento social, por exemplo, além de estressante para animais sociais, pode proporcionar menor estimulação para esses indivíduos. Neste estudo, nós investigamos se o isolamento social prejudica habilidades de aprendizagem no ciclídeo Cichlasoma paranaense. Dois tratamentos foram comparados, um com indivíduos isolados e outro com peixes dominantes de um grupo social. A habilidade de associar uma pista visual com a comida acessível (recompensa) foi medida em uma tarefa espacial. De fato, menos peixes isolados foram capazes de aprender a tarefa. O resultado observado não se deveu a uma diferença na motivação geral para nadar, se alimentar ou explorar as opções de forrageamento. Os resultados indicam que o isolamento social para uma espécie de peixes normalmente social pode prejudicar a aprendizagem
To adjust to changes in the environment, animals can learn about the changes to help them modulate their behaviour as needed. Sometimes, however, changes in the social or the physical environment can generate fear states that trigger a physiological stress response which modifies an individual’s capacity to learn and can have a negative impact on the welfare of the animal. Social isolation, for example, besides being sressful for social animals, may provide less stimulation for these individuals. Here, we investigated whether social isolation impairs learning skills in a cichlid fish, Cichlasoma paranaense. Two treatments were compared, one with isolated individuals and another with dominant fish from a social group. The ability to associate a visual landmark with an accessible food reward was measured in a spatial task. Overall, fewer isolated fish were able to learn the task. The result was not because of a difference in general motivation to swim, feed, or explore the foraging options. The results indicate that social isolation for a normally social species of fish can impair learning
FAPESP: 2012/10903-5

Orientador: Eliane Gonçalves de Freitas
Coorientador: Victoria A. Braithwaite
Banca: Marisa Fernandes de Castilho
Banca: Thaís Billalba Carvalho
Resumo: Para se ajustar a mudanças ambientais, os animais podem aprender sobre tais variações e modular seu comportamento de acordo com suas necessidades. Em alguns casos, no entanto, mudanças no ambiente social ou físico podem gerar estados de medo que levam a respostas de estresse fisiológico e que podem modificar a capacidade de um indivíduo em aprender, impactando negativamente o bem-estar desse animal. O isolamento social, por exemplo, além de estressante para animais sociais, pode proporcionar menor estimulação para esses indivíduos. Neste estudo, nós investigamos se o isolamento social prejudica habilidades de aprendizagem no ciclídeo Cichlasoma paranaense. Dois tratamentos foram comparados, um com indivíduos isolados e outro com peixes dominantes de um grupo social. A habilidade de associar uma pista visual com a comida acessível (recompensa) foi medida em uma tarefa espacial. De fato, menos peixes isolados foram capazes de aprender a tarefa. O resultado observado não se deveu a uma diferença na motivação geral para nadar, se alimentar ou explorar as opções de forrageamento. Os resultados indicam que o isolamento social para uma espécie de peixes normalmente social pode prejudicar a aprendizagem
Abstract: To adjust to changes in the environment, animals can learn about the changes to help them modulate their behaviour as needed. Sometimes, however, changes in the social or the physical environment can generate fear states that trigger a physiological stress response which modifies an individual's capacity to learn and can have a negative impact on the welfare of the animal. Social isolation, for example, besides being sressful for social animals, may provide less stimulation for these individuals. Here, we investigated whether social isolation impairs learning skills in a cichlid fish, Cichlasoma paranaense. Two treatments were compared, one with isolated individuals and another with dominant fish from a social group. The ability to associate a visual landmark with an accessible food reward was measured in a spatial task. Overall, fewer isolated fish were able to learn the task. The result was not because of a difference in general motivation to swim, feed, or explore the foraging options. The results indicate that social isolation for a normally social species of fish can impair learning
Mestre

O presente relatório pretende descrever as atividades desenvolvidas durante o estágio curricular de seis meses no Hospital Veterinário do Restelo, referindo a casuística acompanhada e incluindo uma monografia sobre a síndrome de disfunção cognitiva canina (DCC). A área com maior representatividade foi a clínica médica, com 75,23% do total de casos acompanhados. A DCC é uma síndrome neurodegenerativa, de etiologia multifatorial, que afeta cães, sobretudo a partir dos 11 anos, estando muitas vezes associada a outras afeções, o que pode dificultar o seu diagnóstico. Os sinais clínicos seguem a sigla DISHA, do inglês disorientation (desorientação), interaction (interação), sleep (sono), house soiling (eliminação errática) e activity (atividade). É necessário excluir outras patologias que possam assumir uma sintomatologia semelhante para se poder estabelecer o diagnóstico de DCC. A terapêutica disponível não reverte os sinais clínicos, pelo que o diagnóstico precoce se torna particularmente importante; Abstract: Small animal clinics The present report aims to describe the activities developed during the six-month period traineeship at Hospital Veterinário de Restelo, referring the accompanied casuistry and including a monography about the canine cognitive dysfunction syndrome (DCC). The most represented field was medical clinic, with 75,23% from the total cases. The DCC is a neurodegenerative syndrome, with multifactorial aetiology, that affects dogs mainly above 11 years old. It is often associated to other affections, which may difficult the diagnosis. The clinical signs follow the acronym DISHA, disorientation, sleep, house soiling and activity. It is necessary to exclude other pathologies that may assume a similar symptomatology to establish the DCC diagnosis. The available therapeutics do not revert the clinical signs, making the early diagnosis particularly important.

L’envelliment progressiu de la població pot implicar una major incidència de malalties neurodegeneratives, el que suposa un problema social important que requereix d’investigació. Les regions cerebrals especialment sensibles als efectes de l’envelliment són l’escorça prefrontal (CPF) i l’hipocamp (HPC), amb especial implicació dels seus receptors d’àcid N-metil-D-aspartat (NMDAr) i α-amino-3-hidroxi-5-metil-4-isoxazolpropionic (AMPAr). Donada la implicació d’aquests receptors glutamatèrgics en els processos cognitius, diversos estudis els han utilitzat com a diana per a tractaments destinats a la millora cognitiva. Així doncs, creiem que l’administració d’agonistes glutamatèrgics podrien revertir dèficits cognitius associats a l’envelliment, o induïts per fàrmacs. En la present tesi hem estudiat en rates l’administració intracerebral al còrtex prelímbic (CPL), d’una banda, de l’ampaquina S18986 per reduir els dèficits de memòria produïts per: a) la hipofunció colinèrgica deguda a l’administració d’escopolamina (SCOP) al CPL (Experiment 1) i b) la inactivació amb muscimol (agonista GABAèrgic) del nucli parafascicular del tàlem (PFn) (Experiment 2). S’han avaluat els efectes dels tractaments en paradigmes conductuals de memòria implícita (Discriminació Simple d’Olors, DSO) i relacional (Transmissió Social de Preferència d’Aliment, TSPA). D’altra banda, també hem estudiat la capacitat del tractament amb d-cicloserina (DCS), un agonista parcial dels NMDAr, per a potenciar en rates envellides la memòria de treball (MT) i la flexibilitat cognitiva,dues funcions cognitives clarament minvadesdurant l’envelliment. Els efectes de l’administració intracerebral de DCS al CPL en aquestes funcions i en la memòria a curt i llarg termini, s’han avaluat utilitzant el paradigmes de DelayedMatching / Non-Matching to Position (DMTP/DNMTP),en un laberint en Y i en una tasca operant de respostes alternes(Experiment 3). Els resultats dels experiments 1 i 2 indiquen que l’SCOP al CPL produeix un efecte bloquejadorde la memòria de la DSO en el record a les 24 hores i que la inactivació del PFn impedeix l’adquisició d’aquesta tasca associativa olfactiva. La hipofunció colinèrgica i l‘alteració de la influència talàmica sobre el CPF podrien explicar aquests resultats. L’S18986 va reduir els errors comesos durant l’adquisició de la tascaDSO, respecte el grup control i el grup tractat amb SCOP. Però, en canvi, aquests efectes facilitadors no van observar-se ni en les sessions de retenció, ni en d’altres models conductuals com la TSPA. Diferents aspectes metodològics, com les dosis administrades o el mitjà de dilució del fàrmac, podrien explicar les divergències observades respecte d’altres antecedents experimentals. Els efectes procognitiusmés destacables els hem observat en l’experiment 3, on l’administració intracerebral de DCS ha revertitles alteracions deMT associades a l’envelliment natural. L’administració pre-entrenament de DCS al CPL ha igualat l’execució de les rates velles tractades a la de les rates joves, amb o sense tractament amb DCS. Aquests resultats concorden amb d’altres estudis que mostren com l’efecte beneficiós de la DCS sembla estarassociat a l’existència d’algun tipus de dèficit cognitiu. En general, l’efecte de la DCS ha estat més evident en la MT (DMTP) que en la flexibilitat cognitiva (DNMTP) o en la memòria a curt termini (laberint en Y). Aquestes divergènciespodrien ser conseqüència d’un efecte de sensibilització dels receptors degut a l’administració crònica del tractament ode la finestra temporal d’aplicació. En canvi, en el test de memòria als set dies de l’aprenentatge de la tasca de respostes alternes, el tractament de DCS en els animals vells va facilitar l’execució, igualant-la a la dels grups d’animals joves. L’administraciódels diferents tractaments aplicats en aquesta tesino va tenir cap efecte significatiu en altres variables que podrien haver intervingut en els resultats, com la capacitat olfactòria, la l’activitat motora ola motivació per menjar. Amb els resultats obtinguts en la present tesi aportem coneixement sobre potencials tractaments dirigits a la modulació glutamatèrgica per a revertir dèficits cognitius resultants de l’envelliment, o d’altres patologies associades a disfuncions cerebrals. Tant l’administració de l’S18986 com de la DCS promouen mecanismes de plasticitat sinàptica, com la potenciació a llarg termini,la qual a mésde facilitar la memòria a llarg termini també podria estar implicada en la memòria a curt termini,prodouint una facilitació de tasques amb un component atencional rellevant. Addicionalment, el fet que l’ús d’agonistes parcials redueixi la possibilitat de toxicitat, i que aquests fàrmacs promoguin mecanismes neuroprotectors, converteix a aquests dos fàrmacs en potencials substàncies nootròpiques, les quals podrien servir com a tractament de dèficits cognitius, tenint en compte que es requereix investigació addicional sobre els possibles efectes dosi-dependents, el perfil agonista i d’altres aspectes.
The progressive aging of the population may involve a high incidence of neurodegenerative diseases, which is an important social problem that requires research. The cerebral regions especially sensitive to the effects of aging are the prefrontal cortex (PFC) and the hippocampus (HPC), with special involvement of its receptors N-methyl-D-aspartate (NMDAr) and α-amino-3-hydroxy-5-methyl-4-isoxazolpropionic (AMPARr). Given the involvement of these glutamatergic receptors in the cognitive processes, several studies have used them as targets for treatments aimed at cognitive improvement. Therefore, we believe that the administration of glutamatergic agonists could reverse cognitive deficits associated with aging, or induced by drugs. In the present thesis we have studied in rats the intracerebral administration in the prelimbic cortex (CPL), on the one hand, of the ampakine S18986 to reduce the memory deficits produced by: a) cholinergic hypofunction due to the administration of scopolamine (SCOP) into the CPL (Experiment 1) and b) inactivation of the parafascicular nucleus of the thalamus (PFn) by muscimol (GABAergic agonist) (Experiment 2). The effects of these treatments have been evaluated in behavioural paradigms of implicit memory (Odour Discrimination Task, ODT) and relational memory (Social Transmission of Food Preference, STPF). On the other hand, we have studied the capacity of the treatment with d-cycloserine (DCS), a partial agonist of the NMDAr, to enhance working memory (WM) and cognitive flexibility in aged rats, two cognitive functions clearly depleted during the aging process. The effects of intracerebral administration of DCS in the CPL on these functions and on short- and long-term memory have been evaluated using the paradigms of Delayed Matching / Non-Matching to Position (DMTP / DNMTP), in a Y-maze and in an operant alternate response task (Experiment 3). The results of experiments 1 and 2 indicate that SCOP into the CPL produces a memory-blocking effect on the DSO in the 24-h recall test and the PFn inactivation prevents the acquisition of this associative olfactory task. The cholinergic hypofunction and the alteration of the thalamic influence on the PFC could explain these results. Moreover, S18986 reduced the number of errors committed in the DSO acquisition, respect to the control group and the group treated with SCOP. However, these facilitating effects are not observed, neither in the retention sessions nor in other behavioural models such as the TSPA. Different methodological aspects, such as the administered doses or the dilution medium of the drug, could explain the divergences observed with respect to other experiments. The most remarkable procognitive effects have been observed in the Experiment 3, where the intracerebral administration of DCS has reversed the WM alterations associated with natural aging. The pre-training administration of DCS to the CPL has matched the performance of the treated old rats to the young rats. These results agree with other studies showing that the beneficial effect of DCS seems to be associated with the existence of some kind of cognitive deficit. In general, the effect of DCS has been more evident in WM (DMTP) than in cognitive flexibility (DNMTP) or in short-term memory (Y-maze). These divergences could be a consequence of a sensitization effect of the receptors due to the chronic administration of the treatment or the temporal administrationwindow. On the other hand, in the 7-d memory test of the alternate response task, the DCS treatment in aged animals facilitated itsperformance, equalling it to the young animals. The administration of the different treatments applied in this thesis did not have any significant effect in other variables that could have influenced the results, such as the olfactory capacity, the motor activity or the motivation to eat. With the results obtained in this thesis we provide knowledge about potential treatments aimed at glutamatergic modulation to reverse cognitive deficits resulting from aging, or other pathologies associated with brain dysfunction. Both the administration of S18986 and the DCS promote mechanisms of synaptic plasticity, such as long-term potentiation, which facilitate long-term memory and also short-term memory, providing facilitation of tasks with a relevant attentional component. Additionally, the fact that the use of partial agonists reduces the possibility of toxicity and that these drugs promote neuroprotective mechanisms, turns these two drugs into potential nootropic substances, which could be used as treatment of cognitive deficits, taking into account that additional research is required on the possible dose-dependent effects, the agonist profile and other issues.

Chez les animaux sociaux, les relations supposent des capacités de discrimination/reconnaissance qui peuvent concerner l’espèce, le groupe ou même un individu. La reconnaissance des congénères nécessite d’une part des invariants phénotypiques de l’espèce et une certaine variabilité entre les individus, et d’autre part les capacités cognitives sous-tendant ces processus. Dans l’étude de comportements sociaux, il est légitime de poser la question de savoir comment les individus perçoivent leurs compagnons, comment ils traitent l’information sociale et quels sont les processus cognitifs mis en jeu. Le but de cette étude a été de caractériser les capacités de reconnaissance sociale et individuelle des bovins, Bos taurus, selon le mode visuel avec des images de têtes d’animaux. Les bovins sont une espèce sociale avec une variabilité phénotypique entre les races et entre les individus, favorable à une approche expérimentale. Et la vue est un canal de communication important dans leurs interactions sociales. L’étude d’un groupe social mixte de génisses, produites ou non par clonage, montre des interactions préférentielles entre sujets issus d’un même mode de production et suppose une certaine reconnaissance. Les génisses interagissent aussi davantage avec des images de congénères familiers dans des expériences de discrimination spontanée. Elles traiteraient ces images comme des représentations d’animaux réels. Des expériences de discrimination, basées sur l’utilisation d’un conditionnement instrumental, ont mis en évidence les capacités de catégorisation des bovins et leurs capacités cognitives de reconnaissance sociale et individuelle. L’ensemble des expériences révèle ainsi des capacités de discrimination visuelle de l’espèce, des congénères familiers, de leur apparentement et de reconnaissance individuelle. Les résultats soulignent l’importance de la familiarité dans la reconnaissance et permettent d’envisager l’étude d’une reconnaissance inter-modale chez les bovins
In social animals, relationships are likely supported by capacities of discrimination/recognition at different levels: the species, the social group or even the individual. The recognition of congeners requires stable phenotypic characteristics of the species and some variability among individuals. In the study of social behaviour, it is legitimate to question how individuals perceive their congeners, how they process social information and what are the cognitive processes involved. Animals can have cognitive abilities of social recognition and of complex cognitive abilities involved in individual recognition. Cattle, Bos taurus, are a social species with a wide phenotypic variability between breeds and between individuals, which allow an experimental approach of social and individual recognition. The aim of this study was to characterize cognitive visual capacities in cattle, using still images of faces of animals in a simultaneous discrimination task. Indeed in cattle, vision is an important mode used in social communication. The observation of a mixed group of heifers produced by cloning or artificial insemination (A. I. ) shows preferential interactions between cattle from the same category (clones-clones or A. I. -A. I. ) involving recognition capacities. Moreover, heifers interact more with images of cows and familiar congeners in spontaneous discrimination tasks. This leads to suppose that they associate still images with representations of real animals. Experiences of discrimination, based on the use of instrumental conditioning, show capacities of categorization in cattle and cognitive abilities of individual and social recognition. Our experiments show capacities of visual discrimination of the species, of familiar congeners, of kin and of individual recognition. All the results underline the role of familiarity in the recognition process. New opportunities for the study of inter-modal recognition in cattle are opened

Seed dispersal by endozoochory is important for the maintenance of plant populations and biodiversity. As a result, understanding the impact that frugivores’ activities have on seed dispersal is essential in order to better understand plant population dynamics. One factor that is known to affect an animal’s behaviour, yet has received little attention in this context, is animal cognition i.e. whether the information animals learn and remember affects where they access fruit and deposit seeds. Therefore, the aim of this thesis was to address how animal learning and memory affects the seed dispersal process, using two key approaches – experimental tests of frugivore cognition, and a model paramaterised to examine the consequences of different cognitive abilities on seed dispersal. Three questions were investigated: (1) The “where?” - whether the ability of frugivores to relocate previously visited food sources impacts upon their movements and, as a consequence, on plants’ seed shadows. The spatial learning and memory of red-footed tortoises was tested using an egocentric task. Tortoises were able to navigate efficiently in the environment, and remembered the spatial location of food for at least two months. A seed dispersal model designed to test whether frugivores with different spatial memory skills differently affect plants’ seed shadow, suggested that animals with long spatial memory relocate more efficiently food sources than animals’ with shorter memory. As a consequence, animals with longer memory survived longer, dispersed a bigger amount of seeds, and moved less at random around the environment, all of which lead to different spatial distribution of deposited seeds. (2) The “What?” - whether seed dispersers’ discriminatory skills and memory affects their choice of fruit. Tortoises’ ability to discriminate between quantity and quality of food was tested. They were able to successfully discriminate between the visual cues indicating different types of food and remembered the task for at least 18 months. A seed dispersal model designed to II investigate whether the memory of quality and quantity of food affects seed dispersal showed that the ability to discriminate between the features of fruits and, in particular, the memory of those, allows animals to base their foraging decision on previous learned experiences, significantly increasing the amount of seed dispersed from the preferred fruit. (3) The “When?” - whether the ability to anticipate events, such as food availability, and learn about plants fruiting cycles affects plants’ seed shadows. Tortoises’ anticipatory skills were tested on a 24 h cycle. They were able to anticipate food delivery, showing an increase in activity immediately prior the scheduled food delivery time. A seed dispersal model designed to test the impact of timing on dispersal showed that animals that are able to anticipate cycles equal to or longer than plants’ fruiting cycle readily relocate food, survive longer and disperse more seeds than those with memory that doesn’t last as long as a fruiting cycle. Finally, I present a model parameterised with red-footed tortoise cognitive data, with the aim to test one of the characteristics that makes tortoises unusual as seed dispersal vectors: the use of gaps in the forest. The results suggest that the active use of gaps enhances the probability of seed deposition in gaps and deforested areas, making tortoises a possible reforestation “tool”. I have demonstrated that the study of frugivores’ cognition can help to build more reliable predictions of seed dispersal by endozoochory: cognition is probably the most effective way to understand and predict an animal’s choices and movements around the environment. Future research should incorporate cognition in the study seed dispersal via endozoochory to have more reliable predictions of plant dynamics.

Animal welfare has long been a subject under debate. Since animals are unable to voice concerns about their living standards it is of interest to find other ways to secure their wellbeing. A new measurement has been introduced where animals’ own judgement can act as an indicator for their emotional state and welfare. This study summarizes key elements from previous literature and research in order to explain the connection between welfare and judgement bias. Emotions have been defined as either an observable reaction to a stimulus or a subjective conscious experience of the stimulus. The second has been difficult to assess in animals since they cannot vocalise their own interpretations, hence emotions in animals are assessed based on the first definition. The study of animal welfare is in short the study of animal’s judgement of the world, which in turn indicate how animals feel. Cognitive judgement bias has been defined as whether an animal assess an ambiguous stimulus as negative or positive, a common method used to demonstrate this concept is the go no-go method. Animals learn to discriminate between two stimuli and is then presented with an ambiguous stimulus. The response to the ambiguous stimulus is recorded and determine if the animal is optimistic or pessimistic in its judgement. Research has been rather successful in determining factors which can affect animal welfare, opening up for deeper discussions concerning animal cognition, awareness and their effect on welfare, but further refinements are required to assess the influence of judgement bias.

Thesis (Ph.D.)--Kent State University, 2008.
Title from PDF t.p. (viewed May 21, 2009). Advisor: Marilyn A. Norconk. Keywords: theoretical evolutionary ecology, optimal foraging theory, diet, nutrition, ranging, cognition, colobine monkeys, Semnopithecus entellus. Includes bibliographical references (p. 166-193).

The purpose of this thesis was to develop methodology by which treatments for the cognitive impairments in Huntington's disease (HD) could be tested. As such, the thesis focused mainly on evaluating rats with quinolinic acid (QA) lesions of the striatum, as this manipulation mimics some aspects of the neural damage in Huntington's disease, to try to identify cognitive deficits of HD resulting from cell loss in the striatum. In the first part (Chapters 3-5), the role of the striatum in implicit memory was investigated. Chapter 3 compared the performance of rats and humans on a reaction time task that evaluated implicit memory by presenting visual stimuli with differing probabilities which change over time. Although rats made higher percentage of incorrect responses and late errors, both groups showed a similar pattern of reaction times. Chapter 4 investigated whether implicit memory (the computation of probabilities to predict the location of a stimulus) was affected by selective blockade of dopaminergic transmission at the D1 or D2 receptors by SCH-23390 and raclopride, respectively. Reaction times were slower with SCH-23390 and raclopride, but only SCH-23390 reduced errors to the least probable target location. Chapter 5 used the same task to evaluate implicit memory in rats with QA lesions of the dorsomedial striatum (DMS). Implicit memory was not affected by lesions of the DMS, which suggested that once a task that requires implicit memory has been learned, the DMS was not involved in sustaining the performance of the task. The second part of this thesis (Chapter 6), explored the contribution of the DMS in habit formation. DMS lesioned rats did not show habitual responding, and were not impaired in learning a new goal-directed behaviour. The third part (Chapters 7 and 8), investigated the role of the dorsal striatum in reversal learning, attentional set-formation, and set-shifting. Dorsal striatum lesioned rats were not impaired in reversal learning, but had a diminished shift-cost, which suggested that dorsal striatum lesions disrupted the formation of attentional sets. These results showed that although QA lesions of the dorsal striatum mimic some aspects of the neural damage in HD, they did not result in the same cognitive deficits observed in patients with HD, at least using the tasks presented in this thesis. However, other animal models of HD could be evaluated using the different tasks presented in this thesis to continue the search of a reliable animal model of HD in which treatments for the disease could be evaluated.

Une etude experimentale sur la reaction a la nouveaute a ete conduite sur un materiel biologique encore non etudie de ce point de vue : le loup europeen. Les resultats obtenus lors d'experiences d'introduction et de deplacement d'objets nouveaux, sans valeur biologique, lors d'une procedure d'habituation a ces objets et d'une analyse du role des contraintes sociales sur la reaction a la nouveaute sont conformes a ceux obtenus avec les especes classiquement etudiees. Ces experiences rencontrent aussi les memes difficultes d'interpretation. Les experiences suivantes ont consiste a verifier l'impact des facteurs contextuels sur la reaction a la nouveaute. On fait l'hypothese que l'emplacement des differents objets dans le milieu de vie des animaux joue un role dans leur reaction. L'impact de la structuration spatiale des comportements a donc ete etudie : (a) sur la reaction a des objets nouveaux sans valeur biologique ; (b) sur l'habituation a ces objets ; (c) sur la reaction aux deplacements d'un objet a forte valeur biologique (nourriture) ; (d) sur les relations sociales en situation de changements multiples d'emplacement de la nourriture. L'ensemble de ces travaux est confronte a l'approche cognitiviste et discute dans le cadre de la theorie des systemes autonomes et de la conception ecologique de la perception. A la these de l'enaction, nous empruntons la critique logique de la notion de representation mais conservons une psychologie centree sur la notion de signification. Pour preciser cette notion, nous nous referons a la theorie des affordances en retenant cependant l'effet modulateur de l'etat psychophysiologique du sujet. Le lien entre comportement et perception est exprime par le concept d'acto-spatialite, soit par l'hypothese, corroboree par les resultats, d'une inscription spatiale des comportements des etres etudies. Sur le plan epistemologique, ces developpements posent la question du passage d'un systeme cognitif a un autre.

Les sujets relatifs aux états mentaux, à la conscience ou encore aux intentions des animaux non-humains soulèvent deux difficultés majeures. D'abord l'identification de ces capacités : quelles capacités pour quelles espèces mais aussi qu'elles forment prennent-elles ? Ensuite, l'accès à ces états mentaux internes non directement mesurables : quels outils, métriques, etc. Aborder ces questions revient ainsi à traiter tant ce que recouvre le modèle Animal pour l'observateur (un individu réactif, un individu pensant, etc.) que les paradigmes méthodologiques (par exemple, un état mental peut-il vraiment être inféré à un comportement ?) Pour traiter de cette question, nous explorons comment les intentions sont étudiées chez les animaux, et ce que leurs études pourraient ouvrir comme hypothèses pour l'étude des capacités cognitives. La première étape de notre travail a consisté à repérer les notions mobilisées dans l'étude des intentions dans l'ensemble des disciplines concernées (c'est-à-dire toutes celles où ce concept est étudié). Grâce une analyse bibliométrique étendue, couplée d'un questionnaire à destination de chercheurs, dix approches scientifiques différentes des intentions chez les animaux non-humains ont été identifiées. Dans une seconde des ateliers interdisciplinaires mobilisant éthologues, psychologues, science du design et du management, ont permis, sur la base des 10 approches identifiées, de développer un outil pour considérer les intentions des autres espèces et explorer autrement leurs capacités cognitives. Ce projet ouvre de nouvelles voies prometteuses vers une compréhension scientifique des capacités es animaux non-humains
Subjects relating to the mental states, consciousness and intentions of non-human animals raise two major difficulties. Firstly, identifying these capacities: which capacities for which species, but also what form do they take? Secondly, access to these internal mental states that cannot be directly measured: what tools, metrics, etc. are needed? Addressing these questions means dealing both with what the Animal model covers for the observer (a reactive individual, a thinking individual, etc.) and with methodological paradigms (for example, can a mental state really be inferred from behaviour?). To address this question, we explore how intentions are studied in animals, and what their studies might open up as hypotheses for the study of cognitive abilities. The first stage of our work involved identifying the concepts used in the study of intentions in all the disciplines concerned (i.e. all those in which this concept is studied). Through an extensive bibliometric analysis, coupled with a questionnaire for researchers, ten different scientific approaches to intentions in non-human animals were identified. Secondly, interdisciplinary workshops involving ethologists, psychologists and design and management scientists were held, using the 10 approaches identified as a basis for developing a tool for considering the intentions of other species and exploring their cognitive capacities in a different way. This project opens up promising new avenues towards a scientific understanding of the capacities of non-human animals

I tested two pairs of captive chimpanzees (Pan troglodytes) in the informed forager paradigm: a subordinate saw the location of hidden bait, and then searched with a naïve dominant. This paradigm has tested what subjects know about others' states of knowledge, but my focus was to determine how subjects used different movement types and different gaze types to modify their competitive tactics. In particular, I investigated whether chimpanzees follow opponents' gaze to gain information. Learning more about how primates use visual information to predict others' behaviour can shed light on the continuing debate over to what degree apes possess theory of mind capacities. Previous published studies in this paradigm included narratives of ignorant competitors exploiting informed subjects by following their movement and gaze, and informed subjects avoided this exploitation by walking away from hidden food. The subordinate's behaviour can be considered tactical deception, which is a good place to seek strong evidence of second-order intentionality. Analyses with descriptive statistics, however, fail to capture the complexity of these interactions, which range from single decision-making points to larger patterns of following and misleading. I introduced a novel method of statistical analysis, cross correlations, that enabled me to examine behavioural patterns quantitatively that previous authors have only been able to describe in narrative form. Though previous studies on chimpanzees' understanding of gaze found that they were unable to use (human-given) gaze cues to locate hidden food, the subjects I tested followed their conspecific opponent's gaze, and used information gained from the gaze interaction to modify their own movement towards the hidden bait. Dominants adjusted their physical following of the subordinates as the interaction progressed, which reflected their changed states of knowledge. Subordinates used their movement and gaze differentially to manipulate dominants' behaviour, by withholding information and by recruiting towards a less-preferred bait.

L'avaluació de les emocions és un dels principals objectius de la ciència del benestar animal. El test del biaix cognitiu (BC) s'ha proposat com una mesura per avaluar la valència (positiu vs. negatiu) i la intensitat de les emocions en animals i es basa en la premissa que els subjectes amb un estat emocional negatiu jutjaran un estímul ambigu més negativament que els subjectes amb un estat emocional positiu. L'objectiu del primer estudi va ser avaluar l'aplicabilitat i la consistència del test del BC (TBC) en porcs. Els resultats van mostrar que els porcs eren capaços d'aprendre la tasca de discriminació necessària per posteriorment realitzar el TBC. Malgrat tot, es va observar una inconsistència entre el TBC dut a terme en dos moments diferents. Aquest resultat suggereix que els porcs van canviar la percepció de l’estímul ambigu degut a la capacitat de recordar el resultat d’aquest estímul durant el segon TBC. Els objectius del segon estudi van ser 1) avaluar l’efecte del gènere i del genotip halotà en el BC (utilitzant el TBC) i en el nivell de por (utilitzant el test d’objecte novedós, TON), 2) avaluar la relació entre el BC i el nivell de por i 3) contrastar els resultats del TBC i els del TON amb les concentracions d’una sèrie de neurotransmissors. No es van trobar diferencies entre gèneres i genotips respecte el BC i respecte la por, però es va observar una correlació positiva entre els resultats del TBC i el TON, suggerint que la por juga un paper important en la presa de decisió. A més, els porcs amb més por van presentar concentracions més baixes de dopamina, constatant la relació entre aquest neurotransmissor i la resposta de por. Els objectius del tercer estudi van ser 1) avaluar l’efecte del maneig en el BC (avaluat pel TBC), en la por (avaluat per el TON) i en la resposta de cascada defensiva (avaluat per el test de cascada defensiva, TCD), 2) avaluar l’efecte del maneig en la concentració de cortisol en sèrum, saliva i pel i 3) avaluar la relació entre els testos de comportament (TBC, TON i TCD) i amb les concentracions de cortisol. No es van trobar diferencies entre porcs amb maneig positiu i negatiu respecte els testos de comportament i les concentracions de cortisol, suggerint que el maneig dut a terme no va ser prou intens o que les mesures utilitzades no eren valides o no prou sensibles per avaluar aquestes diferencies. Malgrat tot, es van trobar correlacions positives entre els resultats dels diferents testos de comportament constatant que factors individuals com ara el nivell de por o la motivació van tenir un efecte en l’estat afectiu dels porcs. El quart estudi realitzat tenia per objectiu avaluar l’efecte de les condicions d’allotjament en el TBC, en l’avaluació qualitativa de comportament (AQC), en la concentració sèrica de cortisol i en el número de ferides en les canals dels porcs. Els resultats van mostrar que els porcs allotjats en condicions enriquides tenien millors puntuacions en l’AQC, concentracions de cortisol sèric més baixes i un número més baix de ferides a la canal que els porcs criats en condicions empobrides. Malgrat tot, els resultats del TBC no van mostrar aquestes diferències suggerint que el test no és vàlid o prou sensible per detectar les alteracions emocionals en aquests porcs. En resum, és factible aplicar el TBC en porcs, ja que van realitzar correctament la tasca d’aprenentatge requerida, tot i així, el test no va presentar ni consistència ni validesa qüestionant-ne la utilitat per avaluar l’estat emocional en porcs.
The assessment of animal emotions is a crucial goal in the study of animal welfare science. The cognitive bias (CB) test has been proposed as a measure to assess the valence (positive vs. negative) and the intensity of animal emotions and is based on the premise that subjects in negative emotional state will judge an ambiguous stimulus more negatively than subjects in positive emotional state. The aims of our first study were to assess the applicability and the consistency of the CB test (CBT) in pigs. Our results showed that pigs were able to learn the spatial discrimination task necessary to subsequently perform the CBT. However, there was lack of consistency between the responses of the CBT performed twice, leaving 5 weeks between them. This result suggests that pigs changed the perception of the ambiguous stimulus due to its ability to remember the outcome of the ambiguous stimulus during the second CBT or due to uncontrolled factors such as their age or hunger state over time. The aims of our second study were 1) to assess the effect of the gender and the halothane genotype on CB (using the CBT) and on the level of fear (using a novel object test, NOT), 2) to assess the relationship between the CB and the level of fear and 3) contrast the results of the CBT and the NOT with the concentrations of several brain neurotransmitters. No differences were found between genders and genotypes regarding the CB and regarding the level of fear but a positive correlation was found between the CBT and the NOT results, suggesting that fear plays an important role in the decision taken by the pig dealing with ambiguous stimuli. Moreover, more fearful pigs had lower concentration of dopamine on the prefrontal cortex, supporting the relationship between this neurotransmitter and the fear response. The aims of the third study were 1) to assess the effect of handling on the CB (assessed by a CBT), on the fear (assessed by NOT) and on the defence cascade response (assessed by the defence cascade test; DCT), 2) to assess the effect of handling on serum, saliva and hair cortisol concentration and 3) to assess the relationship between behavioural tests (CBT, NOT and DCT) and between these tests and cortisol concentrations. No differences between positive and negative handling were found regarding the behavioural tests and cortisol concentrations, suggesting that the handling treatment carried out was not powerful enough to induce such differences or that the measures used were not valid or not sensitive enough to assess such differences. Nevertheless, positive correlations were found between behavioural tests supporting that individual factors such as the fear level, the motivation or the coping style had an effect on pigs’ affective state. The fourth study carried out was aimed to assess the effect of housing conditions on the CBT, on the qualitative behaviour assessment (QBA), on the serum cortisol concentration and on the number of wounds on pigs’ carcass. The results showed that pigs raised in enriched housing conditions had better QBA scores, lower serum cortisol concentration and lower number of carcass lesions than pigs raised in barren housing conditions. However, the results of the CBT did not showed those differences suggesting that the test is not valid or not sufficiently sensitive to detect emotional variation in those pigs. In conclusion, is feasible to apply the CBT in pigs, as they performed correctly the required learning process, however, the test showed no consistency and no validity questioning its utility to assess the emotional state in pigs.

La question du bien-être de l'animal ne se pose que si on lui reconnaît le statut d'être sensible, capable de ressentir des émotions. Les émotions dépendent de processus cognitifs qu'entreprend l'animal pour évaluer son environnement. Pour comprendre le passage des émotions à un état de bien-être, nous avons étudié si ces processus cognitifs peuvent être biaisés par les émotions, lesquelles en retour seraient modulées durablement. Un modèle de stress chronique a été développé sur ovins : des agnelles sont exposées de manière répétée à des évènements aversifs, imprévisibles et incontrôlables. L'altération des systèmes neuroendocriniens et la potentialisation de la réactivité émotionnelle confirment que les agnelles ont développé un stress. Ensuite, l'effet de ce stress chronique sur les processus d'évaluation a été exploré : les agnelles stressées montrent une évaluation négative et des déficits d'apprentissage. Enfin, nous avons cherché à savoir si l'induction répétée d'émotions positives chez des agnelles stressées peut contrecarrer les biais d'évaluation négative induits par le stress. Elles évaluent de manière plus positive les événements ambigus que les agnelles uniquement stressées. L'accumulation d'émotions négatives peut conduire l'animal à développer une perception pessimiste de son environnement et une anhédonie, qui contribuent à auto-entretenir l'état de stress. La réduction d'anhédonie après induction répétée d'émotions positives montre que des stratégies cognitivo-comportementales sont envisageables pour corriger un stress. Bien qu'analytiques, ces travaux contribuent à la conception de pratiques d'élevage innovantes améliorant la qualité de vie des animaux.