Virtual reality as a new approach to assess cognitive decline in the elderly

Brain aging is a natural process that leads to a change in cognitive functions. Mild Cognitive Impairment (MCI) is a condition in which a person has cognitive functions that are below normal for his age. However, these deficits are not pronounced enough to confirm for the diagnosis of dementia. It is therefore important to develop new ways to assess cognitive functions in the elderly. This would indeed lead to a better identification of the cognitive losses that are related to normal or pathological aging. The objective of this study was to investigate the relevance of virtual reality as a new evaluation approach in psychology. To do this, 10 elderly people with Mild Cognitive Impairment, and 20 elderly people without cognitive problems, were compared using tests of prospective memory that were presented in a traditional way and in virtual reality. The diagnosis of MCI was made using the Montreal Cognitive Assessment (MoCA). Significant differences between the two groups were noted in virtual reality. Nevertheless, no difference was observed between the two groups with the traditional task. A significant positive correlation between the virtual reality task and the MoCA, but not between the traditional task and the MoCA, was observed. An evaluative approach based on virtual reality seems more sensitive to cognitive impairment associated with aging than an approach based on traditional neuropsychological tests.

3D Interaction Techniques for Virtual Shopping : design and preliminary study

Virtual Reality is now recognized as a powerful tool for the assessment and rehabilitation of both motor and cognitive impairments. In this context, effective Virtual Environments (VEs) that simulate everyday tasks must be proposed. We have developed a virtual supermarket (VS) in which the user can explore and collect various items using a shopping cart. Four interaction techniques have been designed and compared in terms of usability, performance and workload with healthy volunteer participants. These techniques go beyond the desktop paradigm by offering a more immersive and intuitive way of interaction. Results showed that participants were more efficient in terms of performance (completion time and travelled distance) using the game-pad rather than using full body gestures. However, they had more fun performing the task under these conditions

Virtual reality as a screening tool for sports concussion in adolescents

PRIMARY OBJECTIVE: There is controversy surrounding the cognitive effects of sports concussion. This study aimed to verify whether the technique of virtual reality could aid in the identification of attention and inhibition deficits in adolescents. STUDY DESIGN: A prospective design was used to assess 25 sports-concussed and 25 non-sports-concussed adolescents enrolled in a sport and education programme. METHODS AND PROCEDURES: Participants were evaluated in immersive virtual reality via ClinicaVR: Classroom-CPT and in real life via the traditional VIGIL-CPT. MAIN OUTCOMES AND RESULTS: The neuropsychological assessment using virtual reality showed greater sensitivity to the subtle effects of sports concussion compared to the traditional test, which showed no difference between groups. The results also demonstrated that the sports concussion group reported more symptoms of cybersickness and more intense cybersickness than the control group. CONCLUSIONS: Sports concussion was associated with subtle deficits in attention and inhibition. However, further studies are needed to support these results

The Effects of Wealth on Male Reproduction Among Monogamous Hunter-Fisher-Trappers in Northern Siberia

Variability in men’s reproductive success (RS) is partly attributable to the ability of successful men to influence resource flows relevant to the mate choice and reproduction of women. This study explores the effects of variability in resource flows on men’s RS in an indigenous foraging/mixed-economy community in northern Siberia where monogamous marriage norms predominate. A series of material, embodied, and relational wealth indicators are tested as predictors of men’s age-adjusted RS and age at first birth. Material wealth related to hunting, embodied wealth as represented by hunting skill, and relational wealth as represented by numbers of kin are the most consistent predictors of men’s RS. In this monogamous population, the wives of men with more hunting capital and of men rated as better hunters have shorter interbirth intervals, and hunters show strong producer priority. These findings and ethnographic observations appear more consistent with a provisioning model than with a signaling-for-mates model

Boundary rules and breaking of self-organized criticality in 2D frozen percolation

We study frozen percolation on the (planar) triangular lattice, where connected components stop growing (“freeze”) as soon as their “size” becomes at least N, for some parameter N ≥ 1. The size of a connected component can be measured in several natural ways, and we consider the two particular cases of diameter and volume (i.e. number of sites). Diameter-frozen and volume-frozen percolation have been studied in previous works ([5, 15] and [6, 4], resp.), and they display radically different behaviors. These works adopt the rule that the boundary of a frozen cluster stays vacant forever, and we investigate the influence of these “boundary rules” in the present paper. We prove the (somewhat surprising) result that they strongly matter in the diameter case, and we discuss briefly the volume case