The behavioral validity of dual-task driving performance in fixed and moving base driving simulators

Next generation automotive hardware and user interfaces are increasingly pre-tested in driving simulators. What are the potential limitations of such simulations? We determined the relative and absolute validity of five different driving simulators at the Daimler AG by evaluating five functions of an in-vehicle system based on the guideline of the Alliance of Automobile Manufacturers (2006). The simulations were compared to on-road driving. We hypothesized that not only simulator characteristics, but also user characteristics, such as simulator sickness, gender, or age, influence behavioral validity. Even though relating simulator characteristics and user characteristics to driving performance across different driving simulators and driving tasks is difficult, our results are surprisingly in line with the current body of research. We demonstrate the usefulness of all simulators on a relative and partially on an absolute level with moving-base simulators being preferable to fixed-base simulators. As hypothesized, we showed that simulator sickness was significantly associated with impaired performance. In the fixed-base simulators, we found a significant interaction between age and gender, which we could not find in moving-base simulators and in the on-road study. Explanations for our findings and practical implications are discussed.     

细胞因子和抑郁症

在心理神经免疫学领域,越来越多的证据表明神经和免疫之间存在双向交流通路,免疫系统可能在一些心理精神障碍中具有重要作用。“抑郁症的细胞因子假说”认为细胞因子作为神经调质,可能在抑郁症的病因和病理过程中具有重要作用。这个假说得到了很多证据的支持。而在动物身上应用前炎性细胞因子也能够引起与人类抑郁症行为症状非常类似的“病态行为”。研究认为外周细胞因子通过信号传导进入脑内与中枢产生的细胞因子共同作用于下丘脑－垂体－肾上腺轴和5－羟色胺系统,从而导致抑郁症。细胞因子的中枢效应可以解释很多抑郁症状,“抑郁症的细胞因子假说”为探讨抑郁症状的机制和治疗抑郁症提供了一个新的视角     

Stress, Energy, and Immunity: An Ecological View

ABSTRACT— A common perspective on stress-related changes in the human immune system is that such changes are potentially harmful, especially those occurring during chronic stress. In contrast, an ecological perspective views the immune system as an energetically costly system that may or may not have priority over other uses of that energy. From this perspective, the immune system may have energy made available for it via reduction of other activities, may change in energetically conservative ways when the protection it confers needs to be balanced with the energetic demands of other activities such as fight or flight, or may be suppressed when other activities are more important than immunity for total well-being. This last type of change can explain why aspects of psychosocial health such as optimism relate to worse immunity under some circumstances and suggests that both benefits and costs of immunosuppression during stress should be considered in research on human stress and immunity.     

Separation, Sickness, and Depression: A New Perspective on an Old Animal Model

ABSTRACT— Studies of prolonged separation from the attachment figure that were conducted with infant monkeys during the middle of the 20th century identified a passive behavioral response, termed "despair," that appeared to model human depressive illness. Studies in guinea pigs, which exhibit filial attachment that resembles attachment in monkeys, have described a similar passive response to briefer periods of maternal separation. Recent evidence indicates that elements of the immune system mediate the passive behavioral response of guinea pigs. These findings accord well with current ideas that immune responses contribute to depressive illness, suggest new hypotheses about how maternal separation might promote depression, and give us a rodent model in which such hypotheses might be tested.     

Not without hope: a Reformed analysis of sickness and sin.

A Reformed understanding of sickness requires that connections be drawn between the structural effects of sin and the ways that sickness is experienced in people's lives. Such an understanding can be an important resource for the bioethicist, both the bioethicist who speaks from the Reformed tradition and the bioethicist who speaks to patients and caregivers who may assume that sin and sickness are connected, but may understand that linkage in overly simplistic ways.     

The relationship between simulator sickness and driving performance in a high-fidelity simulator

Driving simulators are highly valuable tools for various applications such as research, training, and rehabilitation. However, they are also known to cause simulator sickness, a special form of traditional motion sickness. Common side effects of simulator sickness include nausea, headache, dizziness, eye-strain, and/or disorientation, all symptoms which may negatively impact driving performance. The goal of the present study was to investigate the relationship between simulator sickness and driving performance obtained in a high-fidelity driving simulator. Twenty-one healthy participants were engaged in a simulated driving task containing rural, city, and highway sections for approx. 25 min. Participants were asked to drive naturally while obeying traffic rules and completing common driving maneuvers (including reactions to sudden events). Driving performance was evaluated based on various driving measures, such as lane positioning, speed measures, following distance, or the number of steering reversals. Simulator sickness was measured before, during, and after the simulated drive using a combination of the Simulator Sickness Questionnaire and the Fast Motion Sickness scale. Overall, correlations between the level of simulator sickness and driving performance measures were low to moderate (r’s from -0.37 to 0.40) and were not significant. Additionally, participants who reported higher levels of simulator sickness did not differ with regards to their driving performance from those who reported lower simulator sickness scores. Our results suggest that the presence of simulator sickness is not strongly related to performance in a driving simulator.     

Driving simulation sickness and the sense of presence: Correlation and contributing factors

Driving simulators are useful and effective tools for conducting studies in the field of traffic safety. Simulation sickness (SS) and the sense of presence (SP) are two well-known factors that could affect the results of the driving simulator experiments. This study investigated the relationship between SP and SS in a medium-fidelity driving simulator. Additionally, the impact of the road environment (urban arterials or rural expressways) on these subscales was investigated. Data was collected by means of self-reported questionnaires, which were conducted after the participants have driven the simulation scenarios in a fixed-base medium-fidelity driving simulator. A total of 125 drivers participated in this study. Results showed that females reported significantly higher SS scores than males. An increasing trend in the SS was observed with the increase of age. Importantly, designing buildings that replicate a real-world environment could increase SP and decrease SS. Moreover, designing high quality and resolution scenarios could also increase SP, thus decreasing the severity of SS symptoms. The results of this study can help researchers using medium-fidelity driving simulators to know the influencing factors for each subscale of SP on SS. Adjustments in the driving simulator and scenario settings as well as additional training exercises for higher speed scenarios can be beneficial in reducing the severity of SS.     

Health and Sickness: The Meaning of Menstruation and Premenstrual Syndrome in Women's Lives

The experience of menstruation was examined through an analysis of women's narratives in order to understand perceptions of menstrual cycle changes. Research within a medical anthropology perspective was conducted with 43 women who volunteered for a study on the knowledge and understanding of menstruation and premenstrual syndrome (PMS) in Winnipeg, Manitoba, Canada, from 1997 to 1999. Although most women accepted the PMS label and placed their cyclic changes within the realm of sickness, a small group of women were identified who conceptualized their cyclic changes in an extremely positive way thus reframing their experiences. More positive perceptions of menstrual changes may have a significant impact on the reevaluation of menstrual cycle fluctuations as sickness without devaluing the experiences of those women with severe changes.     

A one year study of coping,social support and quality of life in parkinson's disease

Abstract

The role of coping and social support in the quality of life for Parkinson's Disease (PD) patients is not well understood. Most studies are cross-sectional and concentrate on depression as an outcome measure. The aim of the present study was to explore the role of coping and social support in quality of life for patients with PD. Self-report measures were completed by 105 sufferers of PD; 75 completed the same questionnaire a year later. Patients had the most problems with social function, followed by problems with mobility control and psychological autonomy and communication. After controlling for age, gender and illness duration, the number of PD symptoms predicted mobility control, social functioning and psychological function. Passive coping explained additional variance in most functional domains with more passive coping being related to increased problems. The quality of life was highly stable over the course of the year. Active coping was related to superior psychological functioning one year later. In fact, this was the only coping and social support variable related to functioning after one year, when controlling for previous functions. The results are discussed in terms of the importance of symptom management in PD.