Claude Dumas

Object permanence in cats (Felis catus) : an ecological approach to the study of invisible displacements

A single invisible displacement object permanence task was administered to 19 cats (Felis catus). In this task, cats watched a target object from behind a transparent panel. However, cats had to walk around an opaque panel to reach the object. While cats were behind the opaque panel, the object was hidden behind one of two screens. As cats did not perceive the disappearance of the object behind the target screen, the object was invisibly hidden. Results showed that cats solved this task with great flexibility, which markedly contrasts with what has been observed in previous research. The discussion emphasizes the difference between the typical Piagetian task in which the information necessary to succeed must be dealt with in retrospective way, whereas in our task cats had to anticipate a new position of the object. The ecological relevance of this new task is also discussed.

Can pigeons really make transitive inferences

Fersen, Wynne, Delius, and Staddon (1991) claimed that pigeons are able to make transitive inferences that are logically comparable to the kinds of transitive inferences that have been examined in children. Without putting their methodology or their results into question, analysis of the reinforcement conditions they used indicates that what was actually examined was not transitive inference and that this study does not provide evidence that pigeons are in fact capable of transitive inference

Figurative and spatial information and search behavior in dogs (Canis familiaris).

Domestic dogs (Canis familiaris) were administered a variant of the delayed matching-to-sample task in which they had to recover a hidden object and in which both spatial and figurative information were kept constant at the outset of each trial. Thereafter, either spatial (i.e. spatial condition) or figurative cues (i.e. figurative condition) became relevant to solve the task. The results revealed that dogs rapidly associated a spatial cue with the recovery of the object. The discussion emphasizes the role of cognitive and ecological constraints to account for the fact that figurative information was not readily used as a cue to guide search behavior.

Strategy planning in dogs (Canis familiaris) in a progressive elimination task.

Domestic dogs (Canis familiaris) were administered a progressive elimination task in which they had to visit and deplete three baited sites. Dogs were brought back to the starting point after each visit to any site whether they had made a correct or an incorrect choice. In Experiment 1 (n=10) the results revealed that the dogs randomly selected among the sites when they were equidistant from the starting point whereas they relied on the least distance rule when one of sites was closer to the starting point than were the other sites. In Experiment 2 (n=12), the dogs first chose the left target when angular deviation between adjacent targets varied whether the least angular deviation was on the right of the left. Results are interpreted in terms of Gibsons hypothesis about cooperative hunters. The discussion also emphasizes comparisons with cats (i.e., solitary hunters).

Strategy planning in cats (Felis catus) in a progressive elimination task

Domestic cats (Felis cans) were administered a progressive elimination task in which they had to visit and deplete 3 baited sites. Cats were brought back to the starting point after each visit to any site whether the visit represented a correct or an incorrect choice. The results revealed that cats organized search as a function of the least distance principle whether they had to assess starting point to target distances (Experiment 1, n = 12) or adjacent bowl distances (Experiment 2, n = 12). The results also revealed that the starting point to target distance factor was the most influential in determining the initial choice (Experiment 3, n = 6) and in producing errors. Errors were also linked to the antero-posterior bodily axis of the cat. Results are discussed in terms of the predatory behavior of the cat.

Flexible search behavior in domestic cats (Felis catus): a case study of predator-prey interaction.

Domestic cats (Felis catus) were administered an object permanence task in a novel and a familiar situation to investigate flexibility (i.e., pause behavior and searching by following a path opposite of that taken by the object when it disappeared) in search behavior. Pause and opposite search were assumed to be independent, equiprobable, and randomly exhibited (i.e., random model). The random model predicted that cats would exhibit flexible behavior on 75% of the trials. The results revealed that flexible behavior occurred on 69% of the trials in the novel situation, but only on 52% of the trials in the familiar setting in which pauses were less frequent and shorter than in the novel situation. Thus, the random model provided a good fit of the data in the novel but not in the familiar situation. It is argued that pause and opposite search reflect decision processes when cats are dealing with the behavior of prey that has disappeared while being pursued.

Decision making and interference in the domestic cat (Felis catus).

Domestic cats (Felis catus) received a task in which an obstacle was introduced at the time they were ready to reach for 1 among 2 or 3 baited targets. The results revealed that when the initially chosen direction (i.e., before the introduction of the obstacle) and the new one were orthogonal, the cats reassessed distance, angular deviation, and visibility once they had turned around the obstacle (Experiments 1, 2, and 3). Then the cats chose a different target than the one that would have been chosen had there been no obstacle. When both the initially chosen and the new direction matched (Experiment 4), the cats kept intact their initial decision. The discussion focuses on the nature of the representational system of the cat. The discussion also emphasizes comparisons with dogs (i.e., cooperative hunters).

Decision making and visibility in cats (Felis catus) in a progressive elimination task

When making decisions animals can rely on information stored in memory and/or on information available through perceptual processes. Under some circumstances, perceptual access to a relevant piece of information can be lost as when a prey hides under a cover. If this piece of information is critical, the animal must be able to keep it active in the working memory until the final decision is made. Species endowed with object permanence can to a certain extent overcome such a lack of perceptual access. Numerous studies have investigated object permanence in animals, but no study systematically examined the interaction when making a decision between an information directly available through perception and an information that can no longer be perceived. In the present study, domestic cats (Felis catus) were administered a progressive elimination task in which they had to visit and deplete either two visible and one hidden target (e.g., Experiments 1 and 2) or one visible and two hidden targets (e.g., Experiments 3 and 4). The cats were brought back to the starting point after each visit to any target whether that target had been previously visited or not. The results revealed that the cats searched at the visible target(s) first and at the hidden target(s) last, which was referred to as the visibility rule. The results also revealed that the position of the bowl that was distinct (e.g., the visible bowl when the two other ones were hidden and the opposite) influenced the way this cognitive rule was implemented. More specifically, when the intermediate bowl was distinct the visibility rule was readily implemented but when either the right of the left bowl was distinct the visibility was violated. That is the cats did no longer choose the visible target(s) first. The visibility rule was interpreted in terms of optimization principles, the external distinct target effect was interpreted in terms of divided attention and lateralization.