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Goto, K., Lea, S. E. G., & Dittrich, W. H. (2002). Discrimination of intentional and random motion paths by pigeons. Anim. Cogn., 5(3), 119–127.
Abstract: Twelve pigeons ( Columba livia) were trained on a go/no-go schedule to discriminate between two kinds of movement patterns of dots, which to human observers appear to be “intentional” and “non-intentional” movements. In experiment 1, the intentional motion stimulus contained one dot (a “wolf”) that moved systematically towards another dot as though stalking it, and three distractors (“sheep”). The non-intentional motion stimulus consisted of four distractors but no stalker. Birds showed some improvement of discrimination as the sessions progressed, but high levels of discrimination were not reached. In experiment 2, the same birds were tested with different stimuli. The same parameters were used but the number of intentionally moving dots in the intentional motion stimulus was altered, so that three wolves stalked one sheep. Despite the enhanced difference of movement patterns, the birds did not show any further improvement in discrimination. However, birds for which the non-intentional stimulus was associated with reward showed a decline in discrimination. These results indicated that pigeons can discriminate between stimuli that do and do not contain an element that human observer see as moving intentionally. However, as no feature-positive effect was found in experiment 1, it is assumed that pigeons did not perceive or discriminate these stimuli on the basis that the intentional stimuli contained a feature that the non-intentional stimuli lacked, though the convergence seen in experiment 2 may have been an effective feature for the pigeons. Pigeons seem to be able to recognise some form of multiple simultaneously goal-directed motions, compared to random motions, as a distinctive feature, but do not seem to use simple “intentional” motion paths of two geometrical figures, embedded in random motions, as a feature whose presence or absence differentiates motion displays.
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Uller, C. (2004). Disposition to recognize goals in infant chimpanzees. Anim. Cogn., 7(3), 154–161.
Abstract: Do nonhuman primates attribute goals to others? Traditional studies with chimpanzees provide equivocal evidence for “mind reading” in nonhuman primates. Here we adopt looking time, a methodology commonly used with human infants to test infant chimpanzees. In this experiment, four infant chimpanzees saw computer-generated stimuli that mimicked a goal-directed behavior. The baby chimps performed as well as human infants, namely, they were sensitive to the trajectories of the objects, thus suggesting that chimpanzees may be endowed with a disposition to understand goal-directed behaviors. The theoretical implications of these results are discussed.
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Sachs, E. (1967). Dissociation of learning in rats and its similarities to dissociative states in man. Proc Annu Meet Am Psychopathol Assoc, 55, 249–304.
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Bennett, A. T. (1996). Do animals have cognitive maps? J Exp Biol, 199(Pt 1), 219–224.
Abstract: Drawing on studies of humans, rodents, birds and arthropods, I show that 'cognitive maps' have been used to describe a wide variety of spatial concepts. There are, however, two main definitions. One, sensu Tolman, O'Keefe and Nadel, is that a cognitive map is a powerful memory of landmarks which allows novel short-cutting to occur. The other, sensu Gallistel, is that a cognitive map is any representation of space held by an animal. Other definitions with quite different meanings are also summarised. I argue that no animal has been conclusively shown to have a cognitive map, sensu Tolman, O'Keefe and Nadel, because simpler explanations of the crucial novel short-cutting results are invariably possible. Owing to the repeated inability of experimenters to eliminate these simpler explanations over at least 15 years, and the confusion caused by the numerous contradictory definitions of a cognitive map, I argue that the cognitive map is no longer a useful hypothesis for elucidating the spatial behaviour of animals and that use of the term should be avoided.
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Werner, C. W., Tiemann, I., Cnotka, J., & Rehkamper, G. (2005). Do chickens (Gallus gallus f. domestica) decompose visual figures? Anim. Cogn., 8(2), 129–140.
Abstract: To investigate whether learning to discriminate between visual compound stimuli depends on decomposing them into constituting features, hens were first trained to discriminate four features (red, green, horizontal, vertical) from two dimensions (colour, line orientation). After acquisition, hens were trained with compound stimuli made up from these dimensions in two ways: a separable (line on a coloured background) stimulus and an integral one (coloured line). This compound training included a reversal of reinforcement of only one of the two dimensions (half-reversal). After having achieved the compound stimulus discrimination, a second dimensional training identical to the first was performed. Finally, in the second compound training the other dimension was reversed. Two major results were found: (1) an interaction between the dimension reversed and the type of compound stimulus: in compound training with colour reversal, separable compound stimuli were discriminated worse than integral compounds and vice versa in compound training with line orientation reversed. (2) Performance in the second compound training was worse than in the first one. The first result points to a similar mode of processing for separable and integral compounds, whereas the second result shows that the whole stimulus is psychologically superior to its constituting features. Experiment 2 repeated experiment 1 using line orientation stimuli of reversed line and background brightness. Nevertheless, the results were similar to experiment 1. Results are discussed in the framework of a configural exemplar theory of discrimination that assumes the representation of the whole stimulus situation combined with transfer based on a measure of overall similarity.
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Collier-Baker, E., Davis, J. M., Nielsen, M., & Suddendorf, T. (2006). Do chimpanzees (Pan troglodytes) understand single invisible displacement? Anim. Cogn., 9(1), 55–61.
Abstract: Previous research suggests that chimpanzees understand single invisible displacement. However, this Piagetian task may be solvable through the use of simple search strategies rather than through mentally representing the past trajectory of an object. Four control conditions were thus administered to two chimpanzees in order to separate associative search strategies from performance based on mental representation. Strategies involving experimenter cue-use, search at the last or first box visited by the displacement device, and search at boxes adjacent to the displacement device were systematically controlled for. Chimpanzees showed no indications of utilizing these simple strategies, suggesting that their capacity to mentally represent single invisible displacements is comparable to that of 18-24-month-old children.
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West, R. E., & Young, R. J. (2002). Do domestic dogs show any evidence of being able to count? Anim. Cogn., 5(3), 183–186.
Abstract: Numerical competence has been demonstrated in a wide range of animal species. The level of numerical abilities shown ranges from simple relative numerousness judgements to true counting. In this study we used the preferential looking technique to test whether 11 pet dogs could count. The dogs were presented with three simple calculations: “1+1=2”; “1+1=1”; and “1+1=3”. These calculations were performed by presenting the dogs with treats that were placed behind a screen that allowed manipulation of the outcome of the calculation. When the dogs expected the outcome they spent the same amount of time looking at the result of the calculation as they did on the initial presentation. However, when the result was unexpected dogs spent significantly longer looking at the outcome of the calculation. The results suggest that the dogs were anticipating the outcome of the calculations they observed, thus suggesting that dogs may have a rudimentary ability to count.
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Spinka, M., Duncan, I. J. H., & Widowski, T. M. (1998). Do domestic pigs prefer short-term to medium-term confinement? Appl. Anim. Behav. Sci., 58(3-4), 221–232.
Abstract: A preference test was used to demonstrate that gilts have the ability to associate two sets of neutral cues with two different periods of confinement and water deprivation and to anticipate the long-term consequences of their choice in the test. Twelve gilts housed in two large, straw-bedded pens were trained to go to two sets of 12 crates, positioned on each side of a choice point, for feeding twice a day. Following initial training, the two sets of crates were marked with contrasting visual patterns and the patterns were associated with either 30 min (`short' confinement) or 240 min (`long' confinement) of confinement in the crates after entry. During 16 days of preference testing, the gilts were sent alternately to one side or the other in the mornings and allowed to choose in the afternoons. Eight gilts chose the short confinement side more often, two, the long confinement side more often and two, each side an equal number of times, indicating that most gilts learned the association and preferred to be released shortly after feeding. However, gilts still chose the long confinement side on occasion, suggesting that they did not find 240 min of confinement very aversive. When the gilts were sent to the crates in the morning, their behaviour indicated that they expected to be released or confined depending on which crate they were in. The cognitive abilities of animals with respect to perception of time and anticipation of future events have important implications for their welfare. This study demonstrates that methods can be developed to ask animals about such things.
Keywords: Cognition; Pig-housing; Preference tests
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Murai, C., Tomonaga, M., Kamegai, K., Terazawa, N., & Yamaguchi, M. K. (2004). Do infant Japanese macaques ( Macaca fuscata) categorize objects without specific training? Primates, 45(1), 1–6.
Abstract: In the present study, we examined whether infant Japanese macaques categorize objects without any training, using a similar technique also used with human infants (the paired-preference method). During the familiarization phase, subjects were presented twice with two pairs of different objects from one global-level category. During the test phase, they were presented twice with a pair consisting of a novel familiar-category object and a novel global-level category object. The subjects were tested with three global-level categories (animal, furniture, and vehicle). It was found that they showed significant novelty preferences as a whole, indicating that they processed similarities between familiarization objects and novel familiar-category objects. These results suggest that subjects responded distinctively to objects without training, indicating the possibility that infant macaques possess the capacity for categorization.
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Gallup, G. G. J. (1985). Do minds exist in species other than our own? Neurosci Biobehav Rev, 9(4), 631–641.
Abstract: An answer to the question of animal awareness depends on evidence, not intuition, anecdote, or debate. This paper examines some of the problems inherent in an analysis of animal awareness, and whether animals might be aware of being aware is offered as a more meaningful distinction. A framework is presented which can be used to make a determination about the extent to which other species have experiences similar to ours based on their ability to make inferences and attributions about mental states in others. The evidence from both humans and animals is consistent with the idea that the capacity to use experience to infer the experience of others is a byproduct of self-awareness.
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