Structural validity of miokinetic psychodiagnosis-revised and digitalyzed (MKP-RD) lineograms

In this study, we have applied a principal components analysis to the data obtained from a graphical record of motor behaviour performed without vision. The data was obtained from two samples, one made up of men and the other one made up of women. Hand dominance was controlled in both samples. Five independent factors were obtained: Factor I (Tendency to increase or decrease the length), Factor II (Tendency to deviate in a sagittal direction), Factor V (Tendency to deviate in a frontal direction); two factors (III and IV) were found in a transversal direction. This factor structure did not depend on sex, because the same structure was found in both sexes, nor it could be explained by learning, because the same factors appeared for each hand, except for Factors III and IV which were different for each hand. This study supports different motor dispositions as foundations of behaviour tendencies.     

Great apes' understanding of other individuals' line of sight

Previous research has shown that many social animals follow the gaze of other individuals. However, knowledge about how this skill differs between species and whether it shows a relationship with genetic distance from humans is still fragmentary. In the present study of gaze following in great apes, we manipulated the nature of a visual obstruction and the presence/absence of a target. We found that bonobos, chimpanzees, and gorillas followed gaze significantly more often when the obstruction had a window than when it did not, just as human infants do. Additionally, bonobos and chimpanzees looked at the experimenter's side of a windowless obstruction more often than the other species. Moreover, bonobos produced more double looks when the barrier was opaque than when it had a window, indicating an understanding of what other individuals see. The most distant human relatives studied, orangutans, showed few signs of understanding what another individual saw. Instead, they were attracted to the target's location by the target's presence, but not by the experimenter's gaze. Great apes' perspective-taking skills seem to have increased in the evolutionary lineage leading to bonobos, chimpanzees, and humans.     

Apes know that hidden objects can affect the orientation of other objects

Four bonobos, seven gorillas, and six orangutans were presented with two small rectangular boards on a platform. One of the boards had a piece of food under it so that it acquired an inclined orientation whereas the other remained flat on the platform. Subjects preferentially selected the inclined board. In another experiment, subjects were initially presented with two inclined boards and a transformation took place in which one of the boards fell flat to the platform while the other remained inclined. Subjects also preferred the board that remained inclined. Two additional experiments highlighted some of the possible limitations of their reasoning in this task. Presented with two inclined boards, one of which was visibly supported by a piece of wood, they failed to systematically select the unsupported one whose only reason for being inclined was the presence of the reward. Another experiment presented two rewards in each trial (instead of the customary one) in one of the following two combinations: large banana vs. small carrot or small banana vs. large carrot. Prior to the test, E presented both rewards to the subject and then hid each of them under one of the boards so that both boards were differentially inclined due to the different sizes of the rewards involved. Although subjects selected the board that showed a greater inclination (thus securing the larger reward), they disregarded the type of food that was involved. This often meant that they chose the large carrot over the small banana even though they reversed such a choice when the rewards were not occluded by the boards. Providing subjects with a 'reminder' of the type of reward hidden under the boards did not alter the original results. There was no evidence of learning throughout the various experiments and control tests ruled out the possibility of inadvertent cuing by the experimenter, poor performance due to a lack of motivation, or good performance due to a predisposition to select objects with sloped surfaces. It is concluded that subjects made some inferences about the reason for the inclined orientation of the boards, and not simply associated an inclined orientation with the presence of the reward.     

Do gorillas (Gorilla gorilla) and orangutans (Pongo pygmaeus) fail to represent objects in the context of cohesion violations?

Recent research suggests that witnessing events of fission (e.g., the splitting of a solid object) impairs human infants’, human adults’, and non-human primates’ object representations. The present studies investigated the reactions of gorillas and orangutans to cohesion violation across different types of fission events implementing a behavioral paradigm previously used with human infants. Results suggest that fission events vary in their impact on representational abilities but do not destroy apes’ representations of continuously existing objects.     

Do apes know that they could be wrong?

When confronted with uncertain or incomplete information in decision-making situations, monkeys and apes opt for either escaping the situation or seeking additional information. These responses have been interpreted as evidence of metacognitive abilities. However, this interpretation has been challenged. On the one hand, studies using the information-seeking paradigm have been criticized because subjects may simply engage in a search for information routine (e.g., search until spot the reward) without any metacognitive involvement. On the other hand, studies using the escape response paradigm have been criticized because subjects may not recognize their own state of uncertainty but have learned to use the escape response in the presence of certain stimuli configurations that create uncertainty. The current study attempted to address these two criticisms by presenting great apes (seven gorillas, eight chimpanzees, four bonobos, seven orangutans) with a seeking information task whose basic procedure consisted of presenting two hollow tubes, baiting one of them and letting subjects choose. Conditions varied depending on whether subjects had visual access to the baiting, the cost associated with seeking information, the time interval between baiting and choosing, the food quality and the additional information offered regarding the food’s location. Although subjects showed a high retrieval accuracy when they had witnessed the baiting, they were more likely to check inside the tube before choosing when high stakes were involved (Experiment 3) or after a longer period of time had elapsed between the baiting and the retrieval of the reward (Experiment 2). In contrast, providing subjects with indirect auditory information about the food’s location or increasing the cost of checking reduced checking before choosing (Experiment 1). Taken together, these findings suggest that subjects knew that they could be wrong when choosing.     

Monkeys fail to reciprocate in an exchange task

Exchanges form the basis of human economies. Animals too can engage in reciprocal interactions but they do not barter goods like humans, which raises the question of the abilities necessary for trading to occur. Previous studies have shown that non-human primates can exchange food with human partners. Here, we tested the ability of brown capuchin monkeys and Tonkean macaques to reciprocate in a task requiring two conspecifics to exchange tokens in order to obtain rewards from an experimenter. We recorded 56 transfers between subjects in capuchin monkeys and 10 in Tonkean macaques. All transfers were passive in both species. Capuchins preferentially picked up tokens valuable for them in the partner’s compartment. They tended to manipulate the partner-valued tokens more often than the no-value ones, leading to more opportunities for these tokens to end up within reach of the partner. Despite optimal conditions where values of goods were defined and known by partners, however, none of the pairs tested engaged in short-term reciprocal interactions. These results indicate that calculated reciprocity was difficult if not impossible in the animals tested.     

Prospective object search in dogs: mixed evidence for knowledge of <Emphasis Type="Italic">What</Emphasis> and <Emphasis Type="Italic">Where</Emphasis>

We investigated whether two dogs that had been specially trained to retrieve objects by their names were able to integrate information about the identity (What) as well as the location (Where) of those objects so that they could plan their search accordingly. In a first study, two sets of objects were placed in two separate rooms and subjects were asked to retrieve the objects, one after the other. Both dogs remembered the identity of the objects as they reliably retrieved the correct objects. One of the dogs was also able to integrate information about the object’s location as he chose the correct location in which the object had been placed. Further investigation of the second dog’s behavior revealed that she followed a more stereotyped search strategy. Despite this variation in performance, this study provides evidence for the memory of What and Where in a domestic dog and shows the prospective use of such information in a search task.     

“Spirits are like microbes”: Islamic revival and the definition of morality in Moroccan exorcism

This article analyses the revitalisation of Islamic exorcism in Morocco since the 1990s and how its practitioners legitimise it as a ritual largely adapted to theological orthodoxy. The rhetoric of these exorcists on spirit possession defines certain afflictions as an intromission of the genies (jnun) into the body by physical mechanisms, comparable to the processes undertaken by microbes. From interviews and observation of ritual exorcism of Moroccan faqihs in Tetuan and Barcelona, I analyse their techniques and the way they legitimise them. I conclude that the moral intervention of religious specialists through Koranic recitation becomes effective throughout a dynamic worldview that reinforces old basic assumptions about a physical intercourse between jnun and humans. At the same time, with the revitalisation of the ritual, many Koranic exorcists incorporate new rhetorics to demonstrate scientifically the materiality of the jnun and their effects on the possessed bodies. But Moroccan Koranic healers not only rework definitions of affliction and legitimise the physical agency of the jnun, they also contribute to define gendered experiences of the body as far as women are conceived as the favorite and weakest victims of the genies.