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Miklósi, A., Polgárdi, R., Topál, J., & Csányi, V. (1998). Use of experimenter-given cues in dogs. Anim. Cogn., 1(2), 113–121.
Abstract: Since the observations of O. Pfungst the use of human-provided cues by animals has been well-known in the behavioural sciences (“Clever Hans effect”). It has recently been shown that rhesus monkeys (Macaca mulatta) are unable to use the direction of gazing by the experimenter as a cue for finding food, although after some training they learned to respond to pointing by hand. Direction of gaze is used by chimpanzees, however. Dogs (Canis familiaris) are believed to be sensitive to human gestural communication but their ability has never been formally tested. In three experiments we examined whether dogs can respond to cues given by humans. We found that dogs are able to utilize pointing, bowing, nodding, head-turning and glancing gestures of humans as cues for finding hidden food. Dogs were also able to generalize from one person (owner) to another familiar person (experimenter) in using the same gestures as cues. Baseline trials were run to test the possibility that odour cues alone could be responsible for the dogs' performance. During training individual performance showed limited variability, probably because some dogs already “knew” some of the cues from their earlier experiences with humans. We suggest that the phenomenon of dogs responding to cues given by humans is better analysed as a case of interspecific communication than in terms of discrimination learning.
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Kamil, A. C. (1998). On the Proper Definition of Cognitive Ethology. In Russell P. Balda, Irene M. Pepperberg, & Alan C. Kamil (Eds.), Animal Cognition in Nature (pp. 1–28). London: Academic Press.
Abstract: Summary The last 20-30 years have seen two `scientific revolutions' in the study of animal behavior: the cognitive revolution that originated in psychology, and the Darwinian, behavioral ecology revolution that originated in biology. Among psychologists, the cognitive revolution has had enormous impact. Similarly, among biologists, the Darwinian revolution has had enormous impact. The major theme of this chapter is that these two scientific research programs need to be combined into a single approach, simultaneously cognitive and Darwinian, and that this single approach is most appropriately called cognitive ethology.
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Wittling, W., Block, A., Schweiger, E., & Genzel, S. (1998). Hemisphere Asymmetry in Sympathetic Control of the Human Myocardium. Brain Cogn., 38(1), 17–35.
Abstract: Hemisphere asymmetry in sympathetic control of myocardial performance was studied in healthy human subjects using lateralized film presentation for selective sensory stimulation of the hemispheres and impedance cardiography for the evaluation of cardiac output, systolic time intervals and myocardial contractility. Results revealed a clear and consistent right hemisphere predominance in sympathetically mediated control of various components of myocardial performance. There is reason to assume that the obtained hemisphere differences in autonomic control of the heart are self-reliant processes not depending on emotion-related hemisphere asymmetry. As far as we know, this is the first study examining the distinct roles of the cerebral hemispheres in neural control of ventricular myocardial functions.
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López, J. C., Broglio, C., Rodríguez, F., Thinus-Blanc, C., & Salas, C. (1999). Multiple spatial learning strategies in goldfish (Carassius auratus). Anim. Cogn., 2(2), 109–120.
Abstract: There is a considerable amount of evidence that mammals and birds can use different spatial learning strategies based on multiple learning and memory systems. Unfortunately, only a few studies have investigated spatial learning and memory mechanisms in other vertebrates. This study aimed to identify the strategies used by goldfish to solve two different spatial tasks in a series of three experiments. In experiment 1, two groups of goldfish (Carassius auratus) were trained either in a spatial constancy task (SC), in which visual cues signalled the goal indirectly, or in a directly cued task (DC) in which similar cues signalled the goal directly. Transfer tests were conducted to study the effects of discrete cue deletion on the performance in both tasks. In these transfer tests the performance of the animals trained in the DC task dropped to chance level when the cue that signalled the goal directly was removed. In contrast, the removal of any single cue did not disrupt SC performance. In experiment 2, fish trained in the SC or the DC task were trained with the goal reversed. Goldfish in the SC group needed fewer sessions to master the reversal task than DC animals. Finally, experiment 3 investigated the effects of a substantial modification of the geometrical features of the apparatus on the performance of animals trained in the SC or in the DC condition. The performance of DC goldfish was not affected, whereas the same change disrupted performance in the SC animals despite the presence of the visual cues. These results suggest that there are separate spatial learning and memory systems in fish. Whereas the DC animals used a typical guidance strategy, relying only on the cue that signalled the goal directly, SC fish relied on a strategy with the properties of an actual spatial mapping system. Thus, the comparative approach points to the generality of these learning strategies among vertebrates.
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Potì, P., Langer, J., Savage-Rumbaugh, S., & Brakke, K. E. (1999). Spontaneous logicomathematical constructions by chimpanzees (Pan troglodytes, P. paniscus). Anim. Cogn., 2(3), 147–156.
Abstract: Two experiments investigated the spontaneous construction of precursory logicomathematical operations by human-enculturated and language-reared chimpanzees (Pan troglodytes, Pan paniscus) when they were interacting freely with objects. In experiment 1, three chimpanzees ranging in age from 6 to 18 years were presented with sets of six objects. Chimpanzees constructed equivalence, order and reversibility relations within single sets of objects as well as between two or three contemporaneous sets of objects. The chimpanzees' logicomathematical operations were more advanced, including infrequent and minimal operations on three sets, than those of some previously investigated younger nonenculturated common chimpanzees. In experiment 2, six chimpanzees ranging in age from 6 to 21 years were presented with sets of 12 objects. Chimpanzees constructed more advanced operations on single sets, but not on contemporaneous sets. The results suggest partial convergence and partial divergence between development of logicomathematical cognition in chimpanzees and humans.
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Fountain, S. B., Rowan, J. D., & Benson, D. M. J. (1999). Rule learning in rats: serial tracking in interleaved patterns. Anim. Cogn., 2(1), 41–54.
Abstract: Humans have the ability to chunk together information from nonadjacent serial positions in sequential patterns. For example, human subjects can extrapolate the pattern, A-M-B-N-C-O-D-P-E-..., to find the missing element, Q, by sorting pattern elements into two component interleaved subpatterns: A-B-C-D-E and M-N-O-P-... Two experiments investigated the ability of rats to reorganize pattern elements from nonadjacent serial positions into chunks not presented by the experimenter. Rats learned either a structured or unstructured sequence interleaved with elements of a repeating sequence (experiment 1) or an alternation sequence (experiment 2). In both experiments, rats learned the interleaved subpatterns at different rates. Acquisition rate was correlated with the structural properties of component subpatterns and the nature of the rules required to describe the interleaved subpatterns. The results indicate that rats are sensitive to the organization of nonadjacent elements in serial patterns and that they can detect and sort structural relationships in interleaved patterns.
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Cook, R. G., & Tauro, T. L. (1999). Object-goal positioning influences spatial representation in rats. Anim. Cogn., 2(1), 55–62.
Abstract: Three tests investigated how the geometric relation between object/landmarks and goals influenced spatial choice behavior in rats. Two groups searched for hidden food in an object-filled circular arena containing 24 small poles. For the “Proximal” group, four distinct objects in a square configuration were placed close to four baited poles. For the “Distal” group, the identical configuration of objects was rotated 45° relative to the poles containing the hidden food. The Proximal group learned to locate the baited poles more quickly than the Distal group. Tests with removed and rearranged landmarks indicated that the two groups learned to use the objects differently. The results suggested that close proximity of objects to goals encouraged their use as beacons, while greater distance of objects from goals resulted in the global encoding of the geometric properties of the arena and the use of the objects as landmarks.
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Heiling, A. M., & Herberstein, M. E. (1999). The role of experience in web-building spiders (Araneidae). Anim. Cogn., 2(3), 171–177.
Abstract: A typical feature of vertical orb-webs is the 'top/bottom' asymmetry, where the lower web region is larger than the upper web region. This asymmetry may improve prey capture success, because, sitting in the hub of the web, a spider can reach prey entangled below the hub faster than prey entangled in the area above the hub. While web asymmetry is known to vary intraspecifically, we tested if this variation also exists at the individual level and whether it is the result of experience, using two orb-web spider species, Argiope keyserlingi and Larinioides sclopetarius. The results reveal that experienced web-building spiders constructed more asymmetric webs than conspecifics deprived of any prior building experience over a period of several months. Experienced individuals invested more silk material into the web region below the hub, which covered a larger area. Moreover, web asymmetry was also influenced by previous prey capture experiences, as spiders increased the lower region of the web if it intercepted the most prey over a period of 6 days. Consequently, spiders may be able to use long-term web-building experience as well as short-term prey capture experience to build better traps. In contrast to previous views of spiders, experience can contribute to intraspecific as well as to individual variations in web design.
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Byrne, R. W. (1999). Imitation without intentionality. Using string parsing to copy the organization of behaviour. Anim. Cogn., 2(2), 63–72.
Abstract: A theory of imitation is proposed, string parsing, which separates the copying of behavioural organization by observation from an understanding of the cause of its effectiveness. In string parsing, recurring patterns in the visible stream of behaviour are detected and used to build a statistical sketch of the underlying hierarchical structure. This statistical sketch may in turn aid the subsequent comprehension of cause and effect. Three cases of social learning of relatively complex skills are examined, as potential cases of imitation by string parsing. Understanding the basic requirements for successful string parsing helps to resolve the conflict between mainly negative reports of imitation in experiments and more positive evidence from natural conditions. Since string parsing does not depend on comprehension of the intentions of other agents or the everyday physics of objects, separate tests of these abilities are needed even in animals shown to learn by imitation.
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Mercado, E. I. I. I., Uyeyama, R. U., Pack, A. A., & Herman, L. M. (1999). Memory for action events in the bottlenosed dolphin. Anim. Cogn., 2(1), 17–25.
Abstract: We investigated whether a bottlenosed dolphin’s ability to recall and repeat actions on command would immediately generalize to actions performed with specified objects. The dolphin was tested on her ability to repeat 18 novel behaviors performed with potentially interchangeable objects specified using an artificial gestural language. Such “action events” were correctly repeated at above chance levels, indicating that the dolphin had access to memories of those events. Performance levels were, however, lower than in previous tests. The dolphin appeared to have difficulty recalling which object an action was performed with. Previous research has demonstrated that animals can recall features of their environment and features of their actions independently of one another. The results of this study demonstrate (1) that the dolphin’s concept of repeating extends beyond simply accessing memories of movement patterns, and (2) that dolphins’ memories of past events incorporate representations of both self-performed acts and objects, locations, or gestural instructions.
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