External communication of automated vehicles in mixed traffic: Addressing the right human interaction partner in multi-agent simulation

The urban traffic system is most likely to change in the next years to a mixed traffic with human drivers, vulnerable road users, and automated vehicles. In the past, the development of external communication approaches for automated vehicles focused on scenarios where an automated vehicle communicates with either a pedestrian or a human driver. However, interactions with more than one traffic partner are more realistic. Therefore, a study with 42 participants was conducted with a multi-agent simulation in which an automated vehicle interacted simultaneously with two participants, a pedestrian and a driver of a manual vehicle. In this study, two main scenarios were investigated in order to evaluate the safety and efficiency of the interactions and to determine whether the human road users feel correctly addressed. In one scenario, the pedestrian had to cross the road in front of the automated and the manual vehicle, which were approaching from different sides. In the other, the manual vehicle had to drive through a bottleneck in front of the oncoming automated vehicle, while the pedestrian had to cross the road after both vehicles passed. The communication approach of the automated vehicle consisted of implicit signals using a speed profile and lateral offset within its lane, and explicit signals using an external human–machine interface. The results of the study show that no collisions were observed in terms of safety and no significant negative effects on efficiency were measured. However, in contrast to single agent interactions, a majority of participants felt wrongly addressed in situations where the automated vehicle signals the right-of-way to the other human road user. It can be concluded that the communication approach of the automated vehicle needs to be modified in order to address certain road users more clearly.     

Why male adolescent bicyclists perform risky stunts? A qualitative study

Stunts are one of the main reasons for traffic accidents, particularly among male adolescent bicyclists (ABs). Nonetheless, there are limited data about the theoretical framework of its contributing factors. Moreover, the theoretical frameworks explaining the factors contributing to other risky behaviors have not been used in the area of risky bicycle stunts. The aim of this qualitative study was to explore the factors contributing to risky stunts among male ABs in Iran. This qualitative study was conducted from September 2019 to December 2020 using conventional content analysis. Participants were 29 male ABs purposively selected from Isfahan, Iran. Data were collected through eighteen interviews with sixteen ABs and three focus group discussions with thirteen ABs. Data analysis was conducted concurrently with data collection through conventional qualitative content analysis. The mean of participants’ age was 16.4 ± 1.1 years. Factors contributing to their engagement in risky stunts were grouped into three main themes, namely predisposing personal factors (such as risk underestimation, perceived superiority, sensation seeking, emotional condition, and previous stunt-related experiences), reinforcing social factors (such as supportive social norms and weaknesses of traffic regulations), and environmental conditions (such as time conditions and structural factors). This study provides a new classification of the facilitators to risky stunts among male ABs and reveals new facilitators to these stunts, namely perceived superiority and police non-deterrent reactions to stunts. Therefore, programs on the improvement of safe bicycling should focus not only on perceptual and emotional factors and correction of false perceived superiority through education, but also on social norms and beliefs, regulations, and environmental factors.     

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.     

Does movement proficiency impact on exergaming performance?

There is growing interest in the use of consumer level exergames in movement skill acquisition. The purpose of this study was to investigate the relationship between movement proficiency and performance in virtual exergaming. Twenty seven children, aged 10–15 years participated in an experiment completing the Movement Assessment Battery for Children 2 (MABC-2) and a series of XBOX360 Kinect Sports exergaming tasks. Significant correlations were observed between MABC-2 aiming and catching percentile and exergame javelin and target kick, where the more proficient movers tended to perform better in the exergame. Statistically significant correlations were observed between MABC-2 balance percentile and exergaming sprint and target kick performance. In this study children who scored better in real life gross motor movement tasks performed better in most related exergaming activities. This suggests current exergaming technology has advanced to a point where body movement unencumbered by a physical or remote game device tether can extract movements resembling real life tasks, translate them into game play and reward proficient movers with higher in-game performance. It is possible that benefit gained in an exergaming environment by more proficient movers was a result of either their more proficient movement, or a greater ability to adapt to the exergame.     

The effect of instruction to synchronize over step frequency while walking with auditory cues on a treadmill

Walking to a pacing stimulus has proven useful in motor rehabilitation, and it has been suggested that spontaneous synchronization could be preferable to intentional synchronization. But it is still unclear if the paced walking effect can occur spontaneously, or if intentionality plays a role. The aim of this work is to analyze the effect of sound pacing on gait with and without instruction to synchronize, and with different rhythmic auditory cues, while walking on a treadmill.Firstly, the baseline step frequency while walking on a treadmill was determined for all participants, followed by experimental sessions with both music and footstep sound cues. Participants were split into two groups, with one being instructed to synchronize their gait to the auditory stimuli, and the other being simply told to walk. Individual auditory cues were generated for each participant: for each trial, cues were provided at the participant’s baseline walking frequency, at 5% and 10% above baseline, and at 5% and 10% below baseline.This study’s major finding was the role of intention on synchronization, given that only the instructed group synchronized their gait with the auditory cues. No differences were found between the effects of step or music stimuli on step frequency.In conclusion, without intention or cues that direct the individual’s attention, spontaneous gait synchronization does not occur during treadmill walking.     

Expert athletes activate somatosensory and motor planning regions of the brain when passively listening to familiar sports sounds

The present functional magnetic resonance imaging study examined the neural response to familiar and unfamiliar, sport and non-sport environmental sounds in expert and novice athletes. Results revealed differential neural responses dependent on sports expertise. Experts had greater neural activation than novices in focal sensorimotor areas such as the supplementary motor area, and pre- and postcentral gyri. Novices showed greater activation than experts in widespread areas involved in perception (i.e. supramarginal, middle occipital, and calcarine gyri; precuneus; inferior and superior parietal lobules), and motor planning and processing (i.e. inferior frontal, middle frontal, and middle temporal gyri). These between-group neural differences also appeared as an expertise effect within specific conditions. Experts showed greater activation than novices during the sport familiar condition in regions responsible for auditory and motor planning, including the inferior frontal gyrus and the parietal operculum. Novices only showed greater activation than experts in the supramarginal gyrus and pons during the non-sport unfamiliar condition, and in the middle frontal gyrus during the sport unfamiliar condition. These results are consistent with the view that expert athletes are attuned to only the most familiar, highly relevant sounds and tune out unfamiliar, irrelevant sounds. Furthermore, these findings that athletes show activation in areas known to be involved in action planning when passively listening to sounds suggests that auditory perception of action can lead to the re-instantiation of neural areas involved in producing these actions, especially if someone has expertise performing the actions.     

Is motor knowledge part and parcel of the concepts of manipulable artifacts? Clues from a case of upper limb aplasia

The sensory-motor theory of conceptual representations assumes that motor knowledge of how an artifact is manipulated is constitutive of its conceptual representation. Accordingly, if we assume that the richer the conceptual representation of an object is, the easier that object is identified, manipulable artifacts that are associated with motor knowledge should be identified more accurately and/or faster than manipulable artifacts that are not (everything else being equal). In this study, we tested this prediction by investigating the identification of manipulable artifacts in an individual, DC, who was totally deprived of hand motor experience due to upper limb aplasia. This condition prevents him from interacting with most manipulable artifacts, for which he thus has no motor knowledge at all. However, he had motor knowledge for some of them, which he routinely uses with his feet. We contrasted DC’s performance in a timed picture naming task for manipulable artifacts for which he had motor knowledge versus those for which he had no motor knowledge. No detectable advantage on DC’s naming performance was found for artifacts for which he had motor knowledge compared to those for which he did not. This finding suggests that motor knowledge is not part of the concepts of manipulable artifacts.     

Professional drivers’ fatigue as a problem of the modern era

ObjectiveAll around the world numerous studies have been carried out and indicated that 20–50% of commercial vehicle accidents occur because of fatigue. Professional drivers represent an important category of drivers who are present in traffic on a daily basis transporting passengers or goods and their responsibility is at a very high level. These drivers are most exposed to the impact of fatigue. The review of the literature has provided three main factors which can influence the onset of fatigue: sleep factors, work factors, health factors. The main aim of this study was to determine the influence of the three main factors of fatigue between bus and truck drivers in the Republic of Serbia.MethodsThe survey has been conducted among bus and truck drivers who are employed in transportation companies across the Republic of Serbia. The research consists of collecting and analyzing bus and truck drivers’ answers according to the above mentioned factors which influence the occurrence of fatigue.ResultsIn this study we have found that circadian rhythm, sleep and work factors have an impact on drivers’ fatigue. On the other side, time of going to sleep has no impact on the quality of sleep and on fatigue. The results show that if the drivers work over the legal limit, they are 3 times more likely to sleep less than 6 h in 24 h and if they sleep less than 6 h, it is likely that the poor quality of their sleep will be 8 times higher. The poor quality of sleep reduces driver performance, and therefore increases the risk of accidents.Conclusions2 of 3 investigated factors have an impact on the occurrence of fatigue. The third factor, health factor, should be examined in more detail, and other elements should be analysed in order to determine their influence on the fatigue.     

Influences on anger in German urban cyclists

Previous research shows that anger and aggression among road users lead to maladjusted driving and a higher risk of accidents. Especially cyclists as vulnerable road users have a high risk of being injured if they are involved in accidents. This paper examines reasons for cycling anger in two studies. The first study aimed at identifying anger provoking events. Seventy-three cyclists were invited to discuss anger provoking events in a focus group setting. These events were rated regarding their anger intensity, clustered within focus groups, and aggregated across all groups. The first study revealed 208 unique cycling anger provoking events of varying anger intensity that were summarized in six clusters. The second study aimed at validating these anger provoking events, the ratings, and the clusters. Here, 129 participants were asked to complete a four-time point diary study (over the course of ten days), in which they registered all anger provoking events that they experienced while cycling. The results of this study validated most of the anger provoking events of the first study. Both studies show that most anger provoking events are related to conflicts between cyclists with other road users like car drivers and pedestrians. Moreover, conflicts with car drivers seem to cause stronger anger among cyclists than conflicts with other cyclists or pedestrians. Implications for further research and the planning of road infrastructure are discussed.     

Development of Different Forms of Skill Learning Throughout the Lifespan

The acquisition of complex motor, cognitive, and social skills, like playing a musical instrument or mastering sports or a language, is generally associated with implicit skill learning (SL). Although it is a general view that SL is most effective in childhood, and such skills are best acquired if learning starts early, this idea has rarely been tested by systematic empirical studies on the developmental pathways of SL from childhood to old age. In this paper, we challenge the view that childhood and early school years are the prime time for skill learning by tracking age‐related changes in performance in three different paradigms of SL. We collected data from participants between 7 and 87 years for (1) a Serial Reaction Time Task (SRT) testing the learning of motor sequences, (2) an Artificial Grammar Learning (AGL) task testing the extraction of regularities from auditory sequences, and (3) Probabilistic Category Learning in the Weather Prediction task (WP), a non‐sequential categorization task. Results on all three tasks show that adolescence and adulthood are the most efficient periods for skill learning, since instead of becoming less and less effective with age, SL improves from childhood into adulthood and then later declines with aging.