Many people experience mild stress in modern society which raises the need for an improved understanding of psychophysiological responses to stressors. Heart rate variability (HRV) may be associated with a flexible network of intricate neural structures which are dynamically organized to cope with diverse challenges. HRV was obtained in thirty-three healthy participants performing a cognitive task both with and without added stressors. Markers of neural autonomic control and neurovisceral complexity (entropy) were computed from HRV time series. Based on individual anxiety responses to the experimental stressors, two subgroups were identified: anxiety responders and non-responders. While both vagal and entropy markers rose during the cognitive task alone in both subgroups, only entropy decreased when stressors were added and exclusively in anxiety responders. We conclude that entropy may be a promising marker of cognitive tasks and acute mild stress. It brings out a new central question: why is entropy the only marker affected by mild stress? Based on the neurovisceral integration model, we hypothesized that neurophysiological complexity may be altered by mild stress, which is reflected in entropy of the cardiac output signal. The putative role of the amygdala during mild stress, in modulating the complexity of a coordinated neural network linking brain to heart, is discussed.

The vast majority of P300-based brain-computer interface (BCI) systems are based on the well-known P300 speller presented by Farwell and Donchin for communication purposes and an alternative to people with neuromuscular disabilities, such as impaired eye movement. The purpose of the present work is to study the effect of speller size on P300-based BCI usability, measured in terms of effectiveness, efficiency, and satisfaction under overt and covert attention conditions. To this end, twelve participants used three speller sizes under both attentional conditions to spell 12 symbols. The results indicated that the speller size had, in both attentional conditions, a significant influence on performance. In both conditions (covert and overt), the best performances were obtained with the small and medium speller sizes, both being the most effective. The speller size did not significantly affect workload on the three speller sizes. In contrast, covert attention condition produced very high workload due to the increased resources expended to complete the task. Regarding users’ preferences, significant differences were obtained between speller sizes. The small speller size was considered as the most complex, the most stressful, the less comfortable, and the most tiring. The medium speller size was always considered in the medium rank, which is the speller size that was evaluated less frequently and, for each dimension, the worst one. In this sense, the medium and the large speller sizes were considered as the most satisfactory. Finally, the medium speller size was the one to which the three standard dimensions were collected: high effectiveness, high efficiency, and high satisfaction. This work demonstrates that the speller size is an important parameter to consider in improving the usability of P300 BCI for communication purposes. The obtained results showed that using the proposed medium speller size, performance and satisfaction could be improved.

This paper presents some experimental results on the comparison of users performance for different kinds of 3D interaction tasks (travel, manipulation), when using either a standard desktop display or a large immersive display. The main results of our experimentation are the following: first, not all users benefit similarly from the use of large displays, and second, the gains of performance strongly depend on the nature of the interaction task. To explain these results, we borrow some tools from cognitive science in order to identify one cognitive factor (visual attention) that is involved in the difference of performance that can be observed.

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PurposeIn France, an application decree from February 2002 enumerates a series of operational indicators that companies must offer, including a number of accounting and financial items. The information expected notably includes working time organisation, gender equality, health and safety, disability policies, subcontractor arrangements, water, raw material and energy consumption and biodiversity efforts. The present study aims to account for the diversity of the social and environmental information that companies supply by focusing on three stakeholder categories: suppliers; customers; and employees. It also seeks to highlight possible variations among different sectors of activity; influence of three pillars of sustainability (economic, social and environmental); timeframe (short‐term, long‐term, analytical); and type of discourse (situational or action variables).Design/methodology/approachBased on 40 French companies as a qualitative approach, the purpose of the present communication is to offer a discussion of the structuring modes applied to the information found in sustainability reports targeting stakeholders for all the companies belonging to the CAC 40 index.FindingsMobilizing a structural contents analysis, its findings identify differentiated communications practices among the 40 companies in question. The study also unveils the existence of shorter‐term approaches to sustainability action, contrasting to more long‐term and/or analytical orientations. Finally, the reports in question all emphasized sustainability's “economic” dimension, with its “social” dimension being considered secondary and its “environmental” dimension coming last. This inquiry demonstrates that, in the French context, there is a far cry from corporate social responsibility (CSR) dimension and sustainable development (SD) vision.Originality/valueThe paper provides an in‐depth method to analyze CSR and SD reports through its structural discourse.

A better understanding of how users perform virtual reality tasks may help to build better virtual reality interfaces. In this study, we concentrate on the impact of large displays in virtual reality depending on the tasks and users' characteristics. The two virtual reality tasks studied are the objects manipulation and the navigation in an environment. The users' characteristics studied are the visual attention abilities. Forty subjects participated in the experimentation composed of cognitive tests used to evaluate visual attentional abilities and a set of virtual reality tasks. Our study exhibits two main conclusions. (i) Large displays positively impact on performances for some kinds of virtual reality tasks. (ii) Users with low level of attentional abilities take more advantage of large displays. We conclude that large displays can be considered as cognitive aids depending on the tasks and users' characteristics.

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International audienceThe aim of this study is to examine the decision-making processes at work among French buyers--whether beginners or more experienced individuals, when confronted with a dilemma involving an ethical or non-ethical choice to be made. We go on to illustrate these dilemmas through the use of five original scenarios that reproduce typical situations that arise in a purchasing context in relation to the environment, physical integrity, conflict of interest, or paternalism. Based on 172 participants, the results of our study show that, ethical decision-making depends very clearly on two main factors: expertise and gender. The study also reveals that there is not always a coherent link between ethical choices made and the reasons and justifications given for those choices. Ethical options chosen are not exclusively justified on the grounds of purely ethical reasons but also on the grounds of commercial or economic reasons, or else reasons of avoidance