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Author |
Miller, J.A. |
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Title |
Telling a quagga by its stripes. (extinct South African animal) |
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Journal Article |
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1985 |
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Science News |
Abbreviated Journal |
Sci. News |
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128 |
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70 |
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If, in a mix-up at a costume shop, a couple were issued the front half of a zebra suit and the back half of a horse, it could be considered a quagga disguise. But if the masqueraders were pressed as to whether they were more horse or more zebra, the latest biochemical research advises them to insist on zebra.
The quagga, a South African animal extinct for more than 100 years, has been a source of confusion among taxonomists. Some contend, on the basis of the quagga skins preserved in museums, that this front-striped animal is a zebra, either a fourth zebra species or a variant of the Plains zebra, whose hindquarter stripes are dim. But others have argued that the quagga's teeth and skeleton indicate that its nearest relative is the true horse.
Biochemists joined the fray last year when muscle tissue was obtained from a salt-preserved quagga pelt in a West German museum. The tissue yielded both proteins and genes that could be analyzed (SN:6/9/84, p. 356).
Now the analysis has yielded some results. According to “remarkably concordant” findings on the proteins and on the genes, the quagga was a subspecies of the Plains zebra, says Jerold M. Lowenstein of the University of California at San Francisco. He looked at the binding between a sample of quagga proteins and mixtures of antibodies that bind to blood-serum proteins of each of the extant Equus species. The quagga sample bound more of the antibodies against Plains zebra serum than against the other species. Lowenstein calculates that the quagga relationship with the Plains zebra is six times closer than its relationship with the two other zebra species.
“We had to use special techniques to show the difference,” Lowenstein told SCIENCE NEWS. “There is 99 percent identity on the protein level. All the [Equus] species diverged within the past 5 million years, which is only yesterday in evolutionary terms.”
The quagga-Plains zebra relationship is further supported by the analysis of quagga mitochondrial genes performed by Russell Higuchi and Allan Wilson at the University of California at Berkeley. They find seven times as great a difference between quagga and Mountain zebra DNA as they do between quagga and Plains zebra DNA.
“Stripes, the molecules tell us, do make a zebra,” Lowenstein concludes in the July 18 NEW SCIENTIST, “and the half-striped quagga was a Plains zebra.” |
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Equine Behaviour @ team @ |
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2375 |
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Miller, G. |
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Title |
Animal behavior. Signs of empathy seen in mice |
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Journal Article |
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2006 |
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Science (New York, N.Y.) |
Abbreviated Journal |
Science |
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312 |
Issue |
5782 |
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1860-1861 |
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Altruism; Animals; Behavior, Animal; *Empathy; Formaldehyde/administration & dosage; Mice/*psychology; Motivation; Pain/*psychology; *Social Behavior |
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1095-9203 |
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PMID:16809499 |
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refbase @ user @ |
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461 |
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Milgram, N.W.; Head, E.; Muggenburg, B.; Holowachuk, D.; Murphey, H.; Estrada, J.; Ikeda-Douglas, C.J.; Zicker, S.C.; Cotman, C.W. |
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Title |
Landmark discrimination learning in the dog: effects of age, an antioxidant fortified food, and cognitive strategy |
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Journal Article |
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Year |
2002 |
Publication |
Neuroscience and Biobehavioral Reviews |
Abbreviated Journal |
Neurosci Biobehav Rev |
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26 |
Issue |
6 |
Pages |
679-695 |
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Age Factors; Aging/*physiology; Analysis of Variance; Animals; Antioxidants/*pharmacology; Blood Chemical Analysis/methods; Cognition/*physiology; *Diet; Discrimination Learning/*drug effects/*physiology; Distance Perception/drug effects/physiology; Dogs/physiology; Female; Male; Psychomotor Performance/physiology; Retention (Psychology)/drug effects/physiology; Spatial Behavior/*drug effects/*physiology; Task Performance and Analysis; Time Factors; Vitamin E/blood |
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The landmark discrimination learning test can be used to assess the ability to utilize allocentric spatial information to locate targets. The present experiments examined the role of various factors on performance of a landmark discrimination learning task in beagle dogs. Experiments 1 and 2 looked at the effects of age and food composition. Experiments 3 and 4 were aimed at characterizing the cognitive strategies used in performance on this task and in long-term retention. Cognitively equivalent groups of old and young dogs were placed into either a test group maintained on food enriched with a broad-spectrum of antioxidants and mitochondrial cofactors, or a control group maintained on a complete and balanced food formulated for adult dogs. Following a wash-in period, the dogs were tested on a series of problems, in which reward was obtained when the animal responded selectively to the object closest to a thin wooden block, which served as a landmark. In Experiment 1, dogs were first trained to respond to a landmark placed directly on top of coaster, landmark 0 (L0). In the next phase of testing, the landmark was moved at successively greater distances (1, 4 or 10 cm) away from the reward object. Learning varied as a function of age group, food group, and task. The young dogs learned all of the tasks more quickly than the old dogs. The aged dogs on the enriched food learned L0 significantly more rapidly than aged dogs on control food. A higher proportion of dogs on the enriched food learned the task, when the distance was increased to 1cm. Experiment 2 showed that accuracy decreased with increased distance between the reward object and landmark, and this effect was greater in old animals. Experiment 3 showed stability of performance, despite using a novel landmark, and new locations, indicating that dogs learned the landmark concept. Experiment 4 found age impaired long-term retention of the landmark task. These results indicate that allocentric spatial learning is impaired in an age-dependent manner in dogs, and that age also affects performance when the distance between the landmark and target is increased. In addition, these results both support a role of oxidative damage in the development of age-associated cognitive dysfunction and indicate that short-term administration of a food enriched with supplemental antioxidants and mitochondrial cofactors can partially reverse the deleterious effects of aging on cognition. |
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Life Science Division, University of Toronto at Scarborough, 1265 Military Trail, Scarborough, Ont., Canada M1C 1A4. milgram@psych.utoronto.ca |
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0149-7634 |
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PMID:12479842 |
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Equine Behaviour @ team @ |
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2806 |
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Mezei, A.; Posta, J.; Mihók, S. |
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Title |
Analysis of eventing competition results of Hungarian Sporthorses |
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Conference Article |
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Year |
2012 |
Publication |
Proceedings of the 2. International Equine Science Meeting |
Abbreviated Journal |
Proc. 2. Int. Equine. Sci. Mtg |
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in press |
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Sport horse, eventing, model comparison |
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The aim of the study was to evaluate the Hungarian Sporthorse population based on eventing competition performance. The database contained the results of 792 horses and 449 riders between 1996 and 2006. The eventing results were gathered from Hungary and other European countries. Blom transformed ranks were used to measure competition performance. Sporthorses competed in fourteen categories but only the easiest category (category ’A’) contained enough result to handle it as a single category (model I.). The other 13 categories were handled together based on professional reasons in a different model (model II.). In model III., all records were analysed together and the results were weighted according to the difficulty of the category. The competition results were classified into eight groups, each group had a weight (0-7) and it was multiplied by a constant 3, and the result of this formula was added to the original Blom score. The linear mixed models included fixed effects for age, sex, breeder, owner, location, year and random effects for animal and rider. The model II. contained one more fix effect for difficulty of the competition level. The distribution of number of horses and number of starts by sex were heterogeneous (P<0.05). For category ’A’ mares and geldings appeared in higher proportion, despite this fact ratio of stallions is greater in higher competition levels. Considering the goodness of fit in each model, model fitting to the weighted Blom scores was the best R2=0.82. In model III. every fix effects (age, sex, breeder, owner, location, year) were significant. Random effects for animal and rider were not significant, but form professional point of view they need to be included in the model. The variance components estimated for the weighted Blom scores were the highest also (0.52 rider effect, 0.09 animal effect), the animal x rider interaction effect was zero. The variance proportion of rider effect exceeded the variance proportion of animal effect in each model. Breeding values of eventing performance were predicted using model III. The reliability of the estimated breeding values was acceptable for only a few stallions. To improve the reliability of breeding values, more progenies should be used in eventing competitions (as a kind of progeny test) and more competition records needed (as a kind of own performance test). |
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Corporate Author |
Mezei, A. |
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Xenophon Publishing |
Place of Publication |
Wald |
Editor |
Krueger, K. |
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978-3-9808134-26 |
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Equine Behaviour @ team @ |
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5548 |
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Author |
Mettke-Hofmann, C.; Gwinner, E. |
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Title |
Long-term memory for a life on the move |
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Journal Article |
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Year |
2003 |
Publication |
Proceedings of the National Academy of Sciences of the United States of America |
Abbreviated Journal |
Proc. Natl. Acad. Sci. U.S.A. |
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100 |
Issue |
10 |
Pages |
5863-5866 |
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Animals; Germany; Israel; Memory/*physiology; Models, Biological; Periodicity; Songbirds/*physiology |
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Evidence is accumulating that cognitive abilities are shaped by the specific ecological conditions to which animals are exposed. Long-distance migratory birds may provide a striking example of this. Field observations have shown that, at least in some species, a substantial proportion of individuals return to the same breeding, wintering, and stopover sites in successive years. This observation suggests that migrants have evolved special cognitive abilities that enable them to accomplish these feats. Here we show that memory of a particular feeding site persisted for at least 12 months in a long-distance migrant, whereas a closely related nonmigrant could remember such a site for only 2 weeks. Thus, it seems that the migratory lifestyle has influenced the learning and memorizing capacities of migratory birds. These results build a bridge between field observations suggesting special memorization feats of migratory birds and previous neuroanatomical results from the same two species indicating an increase in relative hippocampal size from the first to the second year of life in the migrant but not in the nonmigrant. |
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Max Planck Research Centre for Ornithology, Department of Biological Rhythms and Behaviour, Von-der-Tann-Strasse 7, 82346 Andechs, Germany. mettke-hofmann@erl.ornithol.mpg.de |
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0027-8424 |
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PMID:12719527 |
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no |
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refbase @ user @ |
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511 |
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Merl, S.; Scherzer, S.; Palme, R.; Möstl, E. |
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Pain causes increased concentrations of glucocorticoid metabolites in horse feces |
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Journal Article |
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Year |
2000 |
Publication |
Journal of Equine Veterinary Science |
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J Equine Vet Sci |
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20 |
Issue |
9 |
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586-590 |
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The concentration of 11,17-dioxoandrostanes (11,17-DOA), a group of cortisol metabolites, was measured using enzyme immunoassay in fecal samples of horses experiencing painful episodes. One group of horses consisted of 10 stallions castrated (samples were collected daily for 10 days); the other group was made up of 29 horses which were brought to an animal hospital because of signs of colic (samples were collected twice daily for six days). Before castration, median concentrations of 10.5 nmol/kg feces were measured. On days 1 and 2 after castration, median 11,17-DOA values increased up to 26.2 and 50.0 nmol/kg feces, respectively, and decreased thereafter to levels lower than at the beginning of the sampling period. High variations were measured between individual cases of colic. In animals with colic, all horses excreted more than 33 nmol 11,17-DOA/kg feces for various periods. The highest concentration measured was 885 nmol/kg feces. One animal out of the 29 colic horses did not show any clinical signs of pain upon arrival in the hospital. The 11,17-DOA values were below 17 nmol/kg feces in all those samples. From this data we conclude, that the concentration of 11,17-DOA in feces is a parameter for painful situations that have occurred one or two days earlier. |
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0737-0806 |
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Equine Behaviour @ team @ |
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6047 |
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Merkies, K.; McKechnie, M.J.; Zakrajsek, E. |
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Behavioural and physiological responses of therapy horses to mentally traumatized humans |
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Journal Article |
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2018 |
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Applied Animal Behaviour Science |
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Equine-assisted therapy; Ptsd; Horse; Behaviour; Cortisol; Heart rate |
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The benefits to humans of equine-assisted therapy (EAT) have been well-researched, however few studies have analyzed the effects on the horse. Understanding how differing mental states of humans affect the behaviour and response of the horse can assist in providing optimal outcomes for both horse and human. Four humans clinically diagnosed and under care of a psychotherapist for Post-Traumatic Stress Disorder (PTSD) were matched physically to four neurotypical control humans and individually subjected to each of 17 therapy horses loose in a round pen. A professional acting coach instructed the control humans in replicating the physical movements of their paired PTSD individual. Both horses and humans were equipped with a heart rate (HR) monitor recording HR every 5secs. Saliva samples were collected from each horse 30 min before and 30 min after each trial to analyze cortisol concentrations. Each trial consisted of 5 min of baseline observation of the horse alone in the round pen after which the human entered the round pen for 2 min, followed by an additional 5 min of the horse alone. Behavioural observations indicative of stress in the horse (gait, head height, ear orientation, body orientation, distance from the human, latency of approach to the human, vocalizations, and chewing) were retrospectively collected from video recordings of each trial and analyzed using a repeated measures GLIMMIX with Tukey's multiple comparisons for differences between treatments and time periods. Horses moved slower (p < 0.0001), carried their head lower (p < 0.0001), vocalized less (p < 0.0001), and chewed less (p < 0.0001) when any human was present with them in the round pen. Horse HR increased in the presence of the PTSD humans, even after the PTSD human left the pen (p < 0.0001). Since two of the PTSD/control human pairs were experienced with horses and two were not, a post-hoc analysis showed that horses approached quicker (p < 0.016) and stood closer (p < 0.0082) to humans who were experienced with horses. Horse HR was lower when with inexperienced humans (p < 0.0001) whereas inexperienced human HR was higher (p < 0.0001). Horse salivary cortisol did not differ between exposure to PTSD and control humans (p > 0.32). Overall, behavioural and physiological responses of horses to humans are more pronounced based on human experience with horses than whether the human is diagnosed with a mental disorder. This may be a reflection of a directness of movement associated with humans who are experienced with horses that makes the horse more attentive. It appears that horses respond more to physical cues from the human rather than emotional cues. This knowledge is important in tailoring therapy programs and justifying horse responses when interacting with a patient in a therapy setting. |
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0168-1591 |
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Equine Behaviour @ team @ |
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6385 |
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Merkies, K.; Isensee, A.; MacGregor, H.; Koenig von Borstel, U.; Tucker, A.; Carson. J.; Bergeron, R. |
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Influence of psychological and physiological arousal in humans on horse heart rate and behaviour |
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Conference Article |
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2012 |
Publication |
Proceedings of the 2. International Equine Science Meeting |
Abbreviated Journal |
Proc. 2. Int. Equine. Sci. Mtg |
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in press |
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horse-human interaction, heart rate, behaviour, human nervousness |
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The interaction of horses with humans is a dynamic state, but it is not clearly understood how horses perceive humans. Nervousness is transmissible from humans to horses indicated by increased horse heart rate (HR), however no studies have investigated whether horses can differentiate between humans who are physiologicallystressed (eg. after exercising) as opposed to psychologically-stressed (eg. feeling nervous/afraid). Horses (N=10) were randomly subjected to each of four treatments: 1) no human [control], 2) a calm human comfortable around horses [CALM; N=2 humans], 3) a physically-stressed human [PHYS; human exercised to reach 70% of maximum HR; N=2 humans], and 4) a psychologically-stressed human [PSYCH; human who was nervous around horses; N=14 humans]. Humans ranked themselves on a scale of 1-10 for their nervousness around horses. Both humans and horses were equipped with a HR monitor. Behavioural observations of the horses [gait, head position relative to the withers, distance from human, orientation toward human] were recorded live. Horses were allowed to wander loose in a round pen for 5 minutes of baseline recordings, at which time the human subject entered the round pen, stood in the centre and placed a blindfold over his/her eyes. The human remained in the centre of the round pen for an additional 5 minutes. Horse HR during control did not differ from when the human was present in the CALM and PSYCH treatment, and was lower during the PHYS treatment (51a vs 54a vs 55a vs 45b bpm for control, CALM, PSYCH and PHYS respectively; a,b differ p<0.0001). Over the 5 minute test period, horse HR decreased in PHYS and PSYCH (p<0.01) whereas it increased in CALM (p<0.0001). Horse HR decreased with increasing human rank of nervousness around horses (p=0.0156), and horses stood nearer to the human when they faced the human (p<0.0001) regardless of treatment. Horses moved at a faster gait in the control treatment, and their gait was slowest in the PSYCH treatment (p<0.0001), and the horse’s head position was lower in the PHYS and PSYCH treatments compared to CALM or baseline (p< 0.0001). A lower horse head position was positively correlated to a lower horse HR (p<0.0001) and negatively correlated to horse age (p<0.0001). Human HR was affected by treatment, with PHYS having the highest HR (p<0.0001). Human HR increased when the horse was facing away from the human, even though the human was blindfolded (p=0.0395). Overall, horses appear to be influenced by the physiological and psychological state of a human without any direct contact. Horses’ posture does reflect their physiological state. Understanding how horses react to human physiological and psychological states is especially important in equine-assisted activities, where the response of the horse has specific implications for the human participant. |
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Corporate Author |
Isensee, A. |
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Xenophon Publishing |
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Wald |
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Krueger, K. |
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978-3-9808134-26 |
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Equine Behaviour @ team @ |
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5545 |
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Mennecke, B.E.; Townsend, A.M.; Hayes, D.J.; Lonergan, S.M. |
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A study of the factors that influence consumer attitudes toward beef products using the conjoint market analysis tool |
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Journal Article |
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Year |
2007 |
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Journal of Animal Science |
Abbreviated Journal |
J. Anim Sci. |
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jas.2006-495- |
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This study utilizes an analysis technique commonly used in marketing, the conjoint method, to examine the relative utilities of a set of beef steak characteristics considered by a national sample of 1,432 US consumers, as well as additional localized samples representing undergraduate students at a business college and in an animal science department. The analyses indicate that among all respondents, region of origin is by far the most important characteristic; this is followed by animal breed, traceability, animal feed, and beef quality. Alternatively, the cost of cut, farm ownership, the use (or non-use) of growth promoters, and whether the product is guaranteed tender were the least important factors. Results for animal science undergraduates are similar to the aggregate results except that these students emphasized beef quality at the expense of traceability and the non-use of growth promoters. Business students also emphasized region of origin but then emphasized traceability and cost. The ideal steak for the national sample is from a locally produced choice Angus, fed a mixture of grain and grass that is traceable to the farm or origin. If the product was not produced locally respondents indicated that their preferred production states are, in order from most to least preferred, Iowa, Texas, Nebraska and Kansas. |
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10.2527/jas.2006-495 |
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Equine Behaviour @ team @ |
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2944 |
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Author |
Mendl, M. |
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Title |
Performing under pressure: stress and cognitive function |
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Journal Article |
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Year |
1999 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
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65 |
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3 |
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221-244 |
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Stress; Cognition; Attention; Learning; Memory; Welfare |
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Abstract |
The way in which cognitive functioning is affected by stressors is an important area of research for applied ethologists because stress caused by captive conditions may disrupt cognitive processes and lead to welfare and husbandry problems. Such problems may be minimised through an understanding of the links between stress and cognition. The effects of stress on cognitive function have been studied in disciplines ranging from human perceptual psychology to animal neuroscience. The aim of this paper is to provide an introduction to this research, focusing on the effects of stressors on attention, memory formation and memory recall. Findings from such a diverse literature with little apparent inter-disciplinary communication are inevitably complex and often contradictory. Nevertheless, some generalities do emerge. The idea that an inverted U-shaped relationship exists between an individual's state of stress or arousal and its ability to perform a cognitive task effectively, the so-called Yerkes-Dodson law, is commonly encountered. The law has limited explanatory value because it is unlikely that different stressors act on cognitive function via the same intervening, non-specific state. Furthermore, the law only provides a very general description of the relationship between stress and cognitive function. Empirical research on attention and memory processes reveals more specific findings. Stressors appear to cause shifts, lapses and narrowing of attention, and can also influence decision speed. These processes may be viewed as serving an adaptive role helping the animal to search for and scrutinise a source of danger. There is conflicting evidence as to whether hormones involved in the hypothalamic-pituitary-adrenal stress response play a part in these processes. These hormones and those involved in the sympathetic-adrenomedullary stress response do appear to play an important role in memory formation. Low or moderate concentrations of circulating glucocorticoids and catecholamines can enhance memory formation, while excessively high or prolonged elevations of these hormones can lead to memory disruption. The effects of stressors on memory recall are less clear. There is evidence for disruptive effects, and for facilitatory effects indicating state-dependent memory recall; events experienced under conditions of high arousal may be best recalled under similar conditions. Applied ethologists have the opportunity to extend work in this area, which often involves studies of single stressors/stress hormones acting in isolation and limited measures of cognitive function, by focusing on real-life husbandry stressors encountered by captive animals. This will yield fundamental information which also has direct relevance to animal welfare and management issues. |
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