Interruptions improve choice performance in gray jays: prolonged information processing versus minimization of costly errors

Under the assumption that selection favors minimization of costly errors, erroneous choice may be common when its fitness cost is low. According to an adaptive-choice model, this cost depends on the rate at which an animal encounters the choice: the higher this rate, the smaller the cost of choosing a less valuable option. Errors should thus be more common when interruptions to foraging are shorter. A previous experiment supported this prediction: gray jays, Perisoreus canadensis, were more error prone when subjected to shorter delays to access to food rewards. This pattern, though, is also predicted by an attentional-constraints model. Because the subjects were able to inspect the rewards during delays, their improved performance when subjected to longer delays could have been a byproduct of the experimentally prolonged opportunity for information processing. To evaluate this possibility, a follow-up experiment manipulated both delay to access and whether rewards could be inspected during delays. Depriving jays of the opportunity to inspect rewards (using opaque lids) induced only a small, nonsignificant increase in error rate. This effect was independent of length of delay and so the jays' improved performance when subjected to longer delays was not simply a byproduct of prolonged information processing. More definitively, even when the jays were prevented from inspecting rewards during delays, their performance improved when subjected to longer delays. The findings are thus consistent with the adaptive-choice model. Electronic Publication     

Amélioration de la qualité de vie au travail dans les unités de soins : la démarche ORSOSA

Improve the quality of working conditions is a major issue for healthcare workers who have to deal with productivity obligations and multiple procedures. Based on the magnet hospital concept, the ORSOSA study (prospective cohort study of 4000 helthcare workers) helped develop and validate a methodolody that allows to quickly diagnose the levels of psychological and organizational constraints (CPO) from the staff’s point of view / of the staff. The ORSOSA method relies on an organisational psychologist who launches a dynamic during the diagnostic feedback phase. He gets the team to appropriate the strengths and weaknesses and to rank their recommendations. This article presents an overview of the method and it the first stages of its evaluations.     

Rôle du cahier des charges et de l’évaluation de sites web sur l’effet de conformité à travers la gestion de contraintes et la qualité ergonomique de pages web

IntroductionPrevious studies have shown that the schedule of conditions orientates the designers’ activity. It leads them to generate and consider more constraints linked to the prescribed ones (provided in the schedule of conditions). In addition, when designers had to evaluate websites before making their productions, they reused into their own productions some characteristic from websites evaluated and visited before designing (that corresponds to the conformity effect).ObjectiveWe carried out an experimental study that aimed to determine the mutual influence of schedule of conditions and conformity effect on constraints accounted by designers and usability quality of the web pages they created. No study has determined the combined effects of these two points of web design on the designers’ activity.MethodTwo groups of professional web designers (the first one dealt with a creative schedule of conditions and the other one with an ergonomic schedule of conditions) had to create two webpages (home page and another one). The experimental study was divided into three successive stages: (1) launching of the two-page design, (2) evaluating two websites, and (3) continuing the two-page design.ResultsThe main results showed that the constraints prescribed in the schedule of conditions affected the first stage of design. Nevertheless, after the evaluation stage (stage 2), this influence decreased during the last design stage (stage 3).ConclusionThe evaluation improved the number of constraints linked to end-users taken into account by the designers during the last stage of their design activity. Nevertheless, the usability quality of web pages created by designers was higher for the designers who dealt with the ergonomic schedule of conditions than for the others.     

Online feedback and the regulation of degrees of freedom in motor control

We tested the hypothesis that the degree to which online feedback is used to control movement influences the regulation of degrees of freedom in a task. Ten participants performed an isometric force production task with their two index fingers with the goal of matching the total force to a target waveform. The role of online feedback was manipulated by changing three factors - the tracking mode, the profile of the target waveform, and the visual gain. The results showed that the coupling between the finger forces was lower in conditions where participants used online feedback to correct their movements compared to conditions where more feedforward strategies were used. The availability of online feedback is dependent on the nature of the task and this contributes to task-dependent changes in the regulation of the degrees of freedom.     

Reflections on how color term acquisition is constrained

Compared with object word learning, young children typically find learning color terms to be a difficult linguistic task. In this reflections article, I consider two questions that are fundamental to investigations into the developmental acquisition of color terms. First, I consider what constrains color term acquisition and how stable these constraints are over culture and age. I review recent studies that have identified conceptual, attentional, and linguistic constraints that seemingly operate on the acquisition of color terms compared with object words and the differential acquisition of color terms within a given language. Second, I consider whether these constraints are specific to the acquisition of color terms or whether they reflect more general constraints that operate on other classes of lexical terms such as different abstract property terms.     

Do 5-month-old infants see humans as material objects?

Infants expect objects to be solid and cohesive, and to move on continuous paths through space. In this study, we examine whether infants understand that human beings are material objects, subject to these same principles. We report that 5-month-old infants apply the constraint of continuous motion to inanimate blocks, but not to people. This suggests that young infants have two separate modes of construal: one for inanimate objects and another for humans.