Chimpanzee (Pan troglodytes) anticipation of food return: coping with waiting time in an exchange task

Despite controversial expectations that animals achieve reciprocal altruism, it is unclear if nonhuman species possess the necessary cognitive abilities. For reciprocal altruism, individuals must anticipate the loss of a commodity and accept a delay before some return. The authors investigated the abilities of 5 chimpanzees (Pan troglodytes) to cope with increasing waiting duration in exchange tasks. Subjects had to keep a small cookie before returning it to a human partner to obtain a larger piece. For a piece 2, 4, or 8 times the size of the small piece, 3 of the 5 subjects waited for up to 4 min. For a piece 40 times larger, 4 of the 5 subjects waited up to 8 min. At long time lag, renouncement to wait occurred earlier than predicted by subjects' general waiting capacity, suggesting that the decision to wait was based on a trade-off between reward quantity and expected costs of the waiting duration. Chimpanzees could anticipate a delayed reward at a time scale of several minutes. If this reflects a cognitive limit in chimpanzees' anticipation capacity, reciprocal altruism by keeping track of costs and benefits over extended periods may be unlikely in chimpanzees.     

Analyse des abandons prématurés lors d’un accompagnement a la validation des acquis de l’expérience (V.A.E.): une recherche empirique

If the VAE’s counseling (validation of knowledge and experience) know a certain success, a lot of candidates have the tendency to termine prematurely the procedure without one can know the precise reasons of it. The present research is based on a sample of 162 subjects that entered to different stages into VAE’s counseling. The comparison between people having quit and those having pursued their VAE carries on self-efficacy, professional and personal social support, self-determination and difficulties met during counseling. A discriminant analysis led between the pursuers and those that don’t pursue as well as the propositions of the participants permit to identify the key variables and to do some recommendations to improve the VAE’counseling.     

The flexibility of source‐monitoring training: Reducing young children's source confusions

The effect of source‐monitoring training on the ability of 3‐ to 4‐year‐old children to discriminate between events seen live and those described in a story was examined. All children saw a live presentation of a target event and heard about a similar target event from a storybook. Three to 4 days later, the children received either source‐monitoring or control training involving a different set of events. Within each training condition, the children were taught to discriminate events (source training) or identify features of events (control training) acquired from sources that were either analogous (live–story events) or partially analogous (live—video events) to the target‐event sources. Immediately after training, all children were asked to monitor the source of the target events seen a few days earlier. The children in both the analogous and partially analogous source‐monitoring training groups more accurately distinguished between the target live and story events than did children in the control training groups. Copyright © 2009 John Wiley & Sons, Ltd.     

Cognitive dissonance induced by writing a counterattitudinal essay facilitates performance on simple tasks but not on complex tasks that involve working memory

This article examines how performance is facilitated with simple tasks and is impaired with complex ones in individuals experiencing dissonance. Experiment 1 measured the performance of dissonance participants at a simple reaction time task. Reaction times were shortest in the dissonance condition. This facilitation effect was interpreted as resulting from increased arousal with dissonance. In Experiment 2, participants performed a more complex secondary memory task that required to memorize and to recall short and long series of numbers. Participants in the dissonance condition performed less well than participants in the no-dissonance condition only under a high memory load and did not differ with a low load. It is suggested that dissonance requires some working memory resources. Accordingly, it is assumed that the arousal properties of dissonance facilitate performance with simple task that do not involve working memory and require a dominant response, but that dissonance impairs performance with tasks that strongly involve working memory.     

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.     

Constraints on statistical computations at 10 months of age: the use of phonological features

Recently, several studies have argued that infants capitalize on the statistical properties of natural languages to acquire the linguistic structure of their native language, but the kinds of constraints which apply to statistical computations remain largely unknown. Here we explored French‐learning infants' perceptual preference for labial‐coronal (LC) words over coronal‐labial words (CL) words (e.g. preferring bat over tab) to determine whether this phonotactic preference is based on the acquisition of the statistical properties of the input based on a single phonological feature (i.e. place of articulation), multiple features (i.e. place and manner of articulation), or individual consonant pairs. Results from four experiments revealed that infants had a labial‐coronal bias for nasal sequences (Experiment 1) and for all plosive sequences (Experiments 2 and 4) but a coronal‐labial bias for all fricative sequences (Experiments 3 and 4), independently of the frequencies of individual consonant pairs. These results establish for the first time that constellations of multiple phonological features, defining broad consonant classes, constrain the early acquisition of phonotactic regularities of the native language.     

Boundaries of American Identity: Relations Between Ethnic Group Prototypicality and Policy Attitudes

We sought to document that the extent to which different ethnic groups are perceived as embodying the American identity is more strongly linked to antiminority policy attitudes and acculturation ideologies among majority‐group members (European Americans) than among minority‐group members (Asian Americans or Latino/as). Participants rated 13 attributes of the American identity as they pertain to different ethnic groups and reported their endorsement of policy attitudes and acculturation ideologies. We found a relative consensus across ethnic groups regarding defining components of the American identity. However, European Americans were perceived as more prototypical of this American identity than ethnic minorities, especially by European American raters. Moreover, for European Americans but not for ethnic minorities, relative ingroup prototypicality was related to antiminority policy attitudes and acculturation ideologies. These findings suggest that for European Americans, perceptions of ethnic group prototypicality fulfill an instrumental function linked to preserving their group interests and limiting the rights afforded to ethnic minorities.     

Both sheep and goats can solve inferential by exclusion tasks

Animal Cognition - Despite the domestication of sheep and goats by humans for several millennia, we still lack comparative data on their cognitive capacity. Comparing the cognitive skills of farm...     

The use of event‐related potentials in the study of early cognitive development

The article by Guillaume Thierry is a welcome one, alerting the field to the exciting ways in which event‐related potentials (ERPs) can be used to study cognitive development. It is also timely: there is great interest in the brain sciences, and in how neuroscience can be applied to cognitive development and indeed to education. In my view, however, the article is perhaps too cautious. It does not seem necessary to delay the use of ERPs in cognitive work until all in the field have agreed on the sound characterization of ERP components. It should be possible for further characterization to proceed hand‐in‐hand with data gathering on applied questions. In fact, as partly noted by Thierry, in the auditory domain well‐characterized ERP components are already available, even for infants (e.g. Cheour et al., 1997; Leppänen and Lyytinen, 1997). Furthermore, it is of developmental interest to study older children as well as infants. If ERPs are seen as a tool to complement existing behavioural investigations, rather than as a stand‐alone method to be used independently, then auditory ERPs can certainly be used in current cognitive‐developmental work. Copyright © 2005 John Wiley & Sons, Ltd.