Driving around bends with or without shoulders: The influence of bend direction

Paved shoulders have long been used to create “forgiving” roads where drivers can maintain control of their vehicles even when as they drift out of the lane. While the safety benefits of shoulders have been well documented, their effects on driver behavior around curves have scarcely been examined. The purpose of this paper is to fill this gap by assessing whether the addition of shoulders affects driver behavior differently as a function of bend direction. Driver behavior in a driving simulator was analyzed on left and right curves of two-lane rural roads in the presence and absence of 0.75-m and 1.25-m shoulders. The results demonstrated significant changes in drivers’ lateral control when shoulders were provided. In the absence of oncoming traffic, the shoulders caused participants to deviate more toward the inner lane edge at curve entry, at the apex and at the innermost position on right bends but not left ones. In the presence of oncoming traffic, this also occurred at the apex and the innermost position, leading participants to spend more time off the lane on right curves. Participants did not slow down in either traffic condition to compensate for steering farther inside, thereby increasing the risk of lane departure on right curves equipped with shoulders. These findings highlight the direction-specific influence of shoulders on a driver’s steering control when driving around bends. They provide arguments supporting the idea that drivers view paved shoulders as a new field of safe travel on right curves. Recommendations are made to encourage drivers to keep their vehicle within the lane on right bends and to prevent potential interference with cyclists when a shoulder is present.     

Dorsolateral prefrontal cortex mediates working memory processes in motor skill learning

Neuroimaging studies have shown that the dorsolateral prefrontal cortex (DLPFC) is recruited during motor skill learning, which suggests the involvement of the DLPFC in working memory (WM) processes, such as selection and integration of motor representations temporarily stored in WM. However, direct evidence linking activation of the DLPFC to WM storage and manipulation during motor skill learning in real-time is rare. In this study, we conducted two experiments to investigate the causal role of DLPFC activity in WM storage and manipulation during motor skill learning under low and high WM-demand conditions. Participants received continuous theta burst stimulation (cTBS) and sham stimulation (crossover design) over the left DLPFC (experiment 1) or right DLPFC (experiment 2). Before and after stimulation, participants in both experiments performed a sequential finger-tapping (SFT) task containing repeated sequence (low-WM demand) and non-repeated sequence (high-WM demand) conditions which are used to study WM processes. The number of correct sequences (NoCS) and reproduction error rate were analyzed. Learning gains in NoCS improved significantly with the practice for both sequence types in the presence of either stimulation type. Compared to sham stimulation, cTBS over the left DLPFC resulted in significantly reduced learning gains in NoCS for non-repeated sequences. These results suggest that the left DLPFC contributes to WM manipulation during motor skill learning.     

Developmental trajectory in the relationship between calculation skill and finger dexterity: A longitudinal study

A 2‐year longitudinal study of 33 children aged 4–6 years was conducted to clarify the developmental relationship between calculation skill and finger dexterity, as well as the selectivity of the predictive power of finger dexterity on later calculation skill. We examined individual developmental change in the relationship between addition performance and finger dexterity and observed whether children fit a linear developmental pattern. Multiple regression analysis showed that participants' performance on addition tests was strongly predicted by their finger dexterity. However, their performance on vocabulary tests was not strongly influenced by finger dexterity. These findings suggest that calculation skill in children aged 4–6 years is strongly related to finger dexterity.     

The effect of driver improvement interventions on crash involvement; has it been under-estimated?

The available evidence suggests that driver improvement interventions (with the aim to increase driver safety, most often by education or training) do not work. The average effect calculated in several meta-analyses is close to, and not always possible to distinguish from, zero, despite total samples sizes of several hundred thousand drivers. However, it is possible that all studies included in these meta-analyses have under-estimated the effect, due to a methodological error; all crashes have been used as dependent variable, instead of only those that the targeted drivers have caused. This error is expected to have considerably deflated the effect sizes, but it is not known how large this effect could be.Using crash data for bus drivers in which culpability had been reliably established, a simple simulation was performed to determine the difference between using culpable and all crashes as an estimator of a safety effect. Using data for six years, calculations were made on single years. About ten percent of culpable crashes in each year were deleted to simulate a safety effect, where after the difference between the original and the simulated variable were calculated, using culpable only and all crashes in parallel. The effects using these two different kinds of datasets could then be compared and the under-estimation effect estimated.Culpable crashes, as compared to all crashes, yielded larger differences in means between time periods, and smaller standard deviations. In between-subjects comparisons resulted in 15–30 percent larger effects for culpable crashes. Within-subjects calculations yielded larger but not as systematic effects.The effect of driver improvement on crash involvement has been systematically under-estimated, as extremely few evaluation studies seem to have taken culpability for crashes into account. Therefore, new evaluations need to be undertaken, and/or old data re-analysed, to calculate a better estimate of the true effect of training and education in driving safety.     

Investigation of drivers’ thresholds of a subjectively accepted driving performance with a focus on automated driving

Lately, the development and implementation of automated driving moved to the center of interest in the automotive industry. In this context, one of the central issues – the configuration of adequate trajectories – is mainly tackled using a technical approach. However, it appears that a technically ideal driving performance does not necessarily coincide with the drivers’ subjective preferences. This study strives to determine thresholds of a subjectively accepted driving performance regarding lateral vehicle control. A second objective is to analyze the influence of selected personal and situational factors on these thresholds. An empirical online survey with 161 participants rating video sequences of driving performances was conducted. The video sequences differed not only with regard to the lateral offset of the ego-vehicle but also concerning the weather (sun/rain) and traffic conditions (existence/driving behavior of oncoming traffic). Additionally, the participants’ driving experience and sensation seeking were considered in the data evaluation. To analyze the data, binary logistic regression analyses were calculated. They revealed that the subjective evaluation of driving performances varies primarily depending on the lateral offset of both the ego-vehicle and the oncoming traffic. The results indicate that regarding the lateral offset certain thresholds of subjectively accepted driving performances do exist. Regarding the development of automated driving systems, two issues need to be considered in order to ultimately guarantee user acceptance. First, the subjective thresholds need to be integrated into the systems’ trajectory planning. Second, the oncoming traffic’s driving behavior has to be considered.     

Effects of Share the Keys (STK), a comprehensive,behavioral-based training program for parents and new teen drivers in New Jersey

The New Jersey Graduated Driver License (GDL) restrictions were updated in 2010 with changes that included a more active role of parents monitoring practice driving with their teens. In addition to extending the driving phases, there were new curfew and passenger limit restrictions. Teen drivers were also required to use red decals on license plates to identify themselves as inexperienced drivers. The Division of Highway Traffic Safety had partnered with the Motor Vehicle Commission in the past to produce practice driving guides for parents of teen drivers, but recognized the need to support this type of informational campaign with an educational program for helping parents to understand changes in the GDL and recognize the importance of their role in the GDL monitoring process. In 2010, the New Jersey Parent/Teen Driver Orientation program was developed to educate parents of teen drivers on the new GDL restrictions and Children’s Hospital of Philadelphia (CHOP) findings concerning the importance of parenting roles in teen driver safety. Additional resources were incorporated into the orientation that included the Centers for Disease Control (CDC) community based information and the University of Michigan Transportation Research Institute (UMTRI) parent-teen driver contracts.This community-based training, known as the New Jersey Parent/Teen Driver Orientation was later renamed Share the Keys, and had been developed for the state as a component of the New Jersey Highway Safety grant received by Kean University. The comprehensive program was designed to engage parents, teens, educators, and law enforcement in the teen driving process and help parents to understand how personal parenting styles and engagement may impact teen crash risk and compliance with the GDL restrictions. Local representatives from traffic safety and law enforcement teamed with school officials and driver education teachers to present programs in their communities. The evaluation process was built into the program as a pre-survey administered at the beginning of the session, a post-survey completed directly afterward, and a voluntary follow-up survey completed on line or mailed, beginning six months later.Evidence from the first year showed that parents maintained a significant level of engagement throughout the GDL process with their teen drivers. However, findings did establish the need to further examine why Authoritative parenting styles had declined, especially since this parenting approach was considered in the literature as most effective in reducing teen crash risks. Therefore, the scope of this study was broadened to a three year effort that reached over 2800 parents and investigated behavioral outcomes impacted by Share the Keys. While comparisons made between driving phases and parenting styles had yielded no significant results, changes within parenting style scores were shown to be effective over time. The reported levels of Permissive and Uninvolved parents remained consistent throughout all three driving phases, while Authoritarian parenting peaked during the Probationary phase, and Authoritative parenting was noted as highest once teens earned their license.     

The role of personal practice in therapist skill development: a model to guide therapists,educators, supervisors and researchers

Prior to 2000, personal practice (PP) for therapists mostly meant personal therapy. Recently a new landscape of PPs has emerged, with meditation-based programs and therapy self-practice/self-reflection (SP/SR) programs playing an increasing role in training and personal/professional development. The challenge now for practitioners and researchers is to refocus on the role of PPs in training and professional development. Are PPs of value - or not? Do they have a role in therapist development? How might PPs enhance therapist skilfulness? Do different PPs act in similar or different ways? Currently, the PP literature lacks a theoretical framework to guide practitioners in their choice of PPs or researchers in their choice of research questions and measures. The purpose of this article is to provide such a framework, the Personal Practice (PP) model. The PP model proposes primary impacts of PPs in four domains: personal development/wellbeing, self-awareness, interpersonal beliefs/attitudes/skills and reflective skills. The model also suggests a secondary impact on therapists’ conceptual/technical skills when therapists use reflection to consider the implications of their PP for their “therapist self”. We offer some suggestions to enhance the quality of future research, and conclude that PPs may play an important and perhaps unique role in therapist training.     

反馈类型和反馈时间对动作技能获得的影响

基于简单直线运动任务和复杂曲线追踪任务,在运动技能获得阶段考察不同反馈类型和反馈时间对操作绩效的影响。结果发现,在复杂曲线轨迹追踪任务中,接受运动轨迹反馈的被试组比接受偏差数值反馈组的成绩更好;即时反馈和延迟反馈组的操作绩效间没有显著差异。在简单直线运动任务中,提供落点偏差的图形反馈组成绩始终优于提供“近/远”信息的文本反馈组;在练习初期,即时反馈组成绩更好。说明,反馈信息的具体-抽象程度影响被试运动技能获得,提供具体直观的轨迹/图形反馈利于运动技能获得;反馈时间对运动技能的影响因任务难度而异。