Physiological markers of traffic-related stress during active travel

Understanding perceptions of safety and comfort (PSC) while walking or cycling is essential to accommodating and encouraging active travel, but current measures of PSC, primarily surveys, suffer from validity and reliability issues. Physiological markers of stress like electrodermal activity and heart rate variability have been proposed as alternative, objective measures of PSC. This paper presents a literature summary and conceptual framework examining the use of physiological stress markers during walking and cycling. The existing studies of active traveller stress markers report inconsistent findings and account for limited controls. We propose a comprehensive conceptual framework to describe the array of dynamic stimuli experienced during active travel, with complex appraisals and multidimensional stress responses that feedback to travel behaviour and stimuli exposure, and culminate in a set of physiological outcomes triggered by activation of the autonomic nervous system – all moderated by numerous personal and trip-related factors. The key challenge of inferring traffic-related fear or discomfort from physiological markers measured on-road is potential confounding effects of: (1) non-traffic factors that induce or modify stress responses, (2) traffic factors that induce stress responses not associated with safety or comfort, and (3) personal and environmental factors that directly influence physiological measurements outside of a stress response. No physiological stress marker has yet been shown to be reliable for on-road active travellers, particularly not for inter-subject comparisons. Physiological markers have the potential to provide high-resolution, objective information about pedestrian and cyclist PSC, but further research, particularly controlled experiments, and more precise study framing are needed to ensure validity and address moderating and confounding factors.     

Quantifying drivers’ comfort-zone and dread-zone boundaries in left turn across path/opposite direction (LTAP/OD) scenarios

The aim of this study is to quantify drivers’ comfort- and dread-zone boundaries in left-turn-across-path/opposite-direction (LTAP/OD) scenarios. These scenarios account for a large fraction of traffic fatalities world-wide. The comfort zone is a dynamic spatiotemporal envelope surrounding the vehicle, within which drivers feel comfortable and safe. The dread zone, a novel concept, describes a zone with a smaller safety margin that drivers will not voluntarily enter, but can push themselves into when conditions provide additional motivation (e.g., when hurried). Quantifying comfort- and dread-zone boundaries in the context of turning left before or after an oncoming vehicle has the potential to inform and improve both the design and driver acceptance of advanced driver assistance systems (ADAS) and autonomous vehicles.Using a within-subject design, a test-track experiment was conducted with drivers turning an instrumented vehicle left across the path of an oncoming vehicle. The oncoming vehicle was a self-propelled full-sized computer-controlled balloon vehicle going straight at a constant speed (50 km/h). The driver assumed full control of the instrumented vehicle approximately 20 m before the intersection and had to make the decision to turn left before or after the oncoming balloon vehicle. There were two experimental conditions, comfortable driving and hurried driving. Measures for each turn included post-encroachment time (PET), lateral acceleration, and self-reports of comfort and risk. Drivers consistently accepted shorter time gaps and higher lateral accelerations when hurried. We interpret these findings to suggest that drivers invoke two dynamic, contextually-defined safety margins. The first is the comfort-zone boundary, a limit which drivers do not voluntarily cross without extra motives. The second is the dread-zone boundary, a more distant limit which drivers do not voluntarily cross even with extra motives. Grouping the responses (high/low) to the driver behavior questionnaire (DBQ) improved the ability to predict the dread-zone boundary PET given the comfort-zone boundary PET.     

Investigating relationships among perceptions of yielding,safety, and comfort for pedestrians in unsignalized crosswalks

Interactions with other road users influence the perceived safety and comfort of pedestrians. Yet the relationships among perceptions of yielding, safety, and comfort are poorly understood. To enhance understanding of these key concepts, the objectives of this study are to determine how perception of pedestrian safety at unsignalized crosswalks differs from perception of comfort, and the relationship of each with perception of yielding. A generalized structural equations model is developed using data from an online survey in which 366 participants (i.e., “perceivers”) rated yielding, safety, and comfort for sample videos of pedestrian interactions with motor vehicles and bicycles. Results show that an individual’s perception of yielding plays a crucial role in mediating the effects of interaction attributes (e.g., vehicle speed, proximity) and perceiver attributes (e.g., travel habits) on their perceptions of pedestrian safety and comfort. For example, people who bicycle more frequently perceive pedestrians as more comfortable than people who walk more frequently, rooted in misalignment on what constitutes adequate yielding. Strategies to address pedestrian comfort can focus on a set of key yielding behaviors by drivers and cyclists – particularly allowing the pedestrian to cross first. Motor vehicle drivers must exhibit stronger yielding behavior (e.g., allow a larger time gap) than bicycles to achieve the same level of perceived pedestrian safety and comfort. Although perceptions of safety and comfort are strongly related and similarly impacted by yielding, researchers should be cautious about using the concepts interchangeably because they are differently impacted by attributes of the interaction and perceiver.     

The influence of auditory feedback on speed choice, violations and comfort in a driving simulation game

Two experiments are reported which explore the relationships between auditory feedback (engine noise), speed choice, driving violations and driver comfort. Participants played a driving simulation game with different levels of auditory feedback in the form of engine noise. In Experiment 1, a between-subjects design revealed that no noise and low levels of engine noise (65 dB(A)) resulted in participants driving at faster speeds than in the medium (75 dB(A)) and high (85 dB(A)) levels of engine noise conditions. The low noise feedback conditions were also associated with decreases in driver comfort. Experiment 2 also demonstrated that low levels of engine noise feedback (no feedback and 70 dB(A)) were associated with increases in driving speed, and driving violations relative to higher levels of feedback (75 dB(A) and 80 dB(A)). Implications exist for current car manufacturing trends which emphasise a growing increase in noise insulation for the driver.     

Cyclists' perception of cycling infrastructure – A Repertory Grid approach

Previous research indicate that cyclists prefer safe and comfortable infrastructure. However, concepts like safety or comfort may be understood and defined in different ways by different individuals. Moreover, these concepts are so broad that it is unclear to which specific characteristics of the traffic infrastructure they are linked. Therefore, the aim of this study is to inductively examine individual evaluation criteria that cyclists use to perceive and evaluate certain route attributes. Using the Repertory Grid technique, we elicited the personal constructs of 23 participants about given route attributes and asked them to rate every attribute on every construct. The constructs were categorized and clustered resulting in five evaluation criteria, namely Mental Comfort, Physical Comfort, Interaction, Environment, and Ease of Use. Both comfort clusters were rated the most relevant for route choice, but they strengthen the suggestion of two distinct aspects of comfort, one referring to mental stress, the other referring to physical effort. Furthermore, the analyses revealed Interaction as a relatively new route criterion which also raises a new view on the negative evaluation of motor traffic and expands the concept of stress. Regarding the evaluation of route attributes, a high traffic volume and cobbled stone were rated the most negative, whereas separated cycling facilities were evaluated as most positive. Findings of this study expand existing research by qualitative insights and provide a more detailed understanding of route criteria like comfort or safety. This can be used to enhance cycling facilities and to offer preferable infrastructure for cyclists.     

Bicyclists’ behavioral and physiological responses to varying roadway conditions and bicycle infrastructure

Population growth increase of vehicle ownership, and development patterns have resulted in greater levels of congestion, pollution, and crash frequency. A proposed solution to lessen current transportation system demands is to increase the share of bicycle trips. Furthermore, as cycling is perceived by some as both a dangerous and stressful mode of transportation, understanding the factors that lead to less comfortable and stressful riding, can help drive bicycle infrastructure development. To establish a more robust understanding of the behaviors of bicyclists and how infrastructure design and operations influence them, a bicycle simulator was used to evaluate bicyclist performance measures of velocity, horizontal displacement, and physiological responses (i.e., galvanic skin response) while riding in varying roadway conditions. Results showed that bicyclists in the bike lane condition, had a GSR reading 1.77 peaks per min less than when cycling in the no bike lane condition. When bicyclists were in no bike lane condition, the GSR reading was not affected by vehicle speed but it was affected by the vehicular volume. Additionally, females felt less comfortable when riding in either bike condition, even though they reported that they were “Strong and Fearless” riders. The methodology used for this study sets forth the foundation for future research that could evaluate varying facility designs and a wider range of individuals.     

The presence of and search for a calling: Connections to career development

The current study explored the relationship of the presence of, and search for, a calling to the career development of 3091 first year college students. The presence of a calling correlated positively with decidedness, comfort, self clarity and choice-work salience and correlated negatively with indecisiveness and lack of educational information. The search for a calling correlated negatively with decidedness, comfort, self clarity, and choice-work salience and correlated positively with indecisiveness and lack of educational information. Hierarchical regression analyses revealed that for both career decidedness and choice comfort, the calling variables taken together added 8% and 5% variance, respectively, above and beyond that accounted for by self clarity, choice-work salience, indecisiveness, and lack of educational information. It is suggested that future research investigate the potential sources of a career calling and counselors be open to exploring this construct with individual clients.     

Self-help and the surfacing of identity: Producing the Third Culture Kid

In this paper, I argue for a need to expand our understanding of the role that self-help plays in the constitution of identities. Using the example of the Third Culture Kid (TCK) industry, I argue that self-help acts as a space of biopower through its role in managing the emotional experience of having been globally mobile as a child. To do this, the paper looks at how the TCK, as a subject, is surfaced as comfort in relation to the ascribed grief and insecurity of identity that is associated with childhood global mobility. Data are derived from a multi-sited ethnography, including a narrative analysis of TCK literature, reader discussions, participant observation at a TCK event and an online survey. The argument contributes to scholarly critiques of self-help by examining processes of production and consumption of TCK subjectivity enacted through the TCK industry. Thereby, the paper contends that in researching self-help we need a wider understanding of its production and consumption, how people are persuaded to use it, and how they respond to ideas presented within it.     

Counselor preference and anticipated comfort ratings for a clinic sample of sexually abused versus non-abused girls

We compared counselor preference and anticipated comfort ratings for sexually abused and non-abused girls. Twenty-five sexually abused and 22 non-sexually abused girls between ages 7 and 17 participated in an initial psychological evaluation at a university outpatient clinic. Results obtained using the Counselor Preference and Comfort Survey revealed no significant difference between sexually abused and non-abused girls' ratings of their preference for male or female counselors and their anticipated comfort with male counselors; non-abused girls expressed significantly higher anticipated comfort with female counselors than did their abused counterparts. It was illustrated that younger girls', abused and non-abused, were more likely to prefer a female counselor and to anticipate being more comfortable with a female counselor. In addition, older non-abused girls were more likely to prefer a male counselor and more likely to anticipate being comfortable with a male counselor. Participants in both groups expressed a higher preference for and anticipated comfort with female counselors as compared with male counselors.     

Comprendre l'attachement au travail pour agir sur le confort au travail

Workplace attachment is defined as the emotional bond resulting from the dynamic interaction between a person and his environment (Rioux, 2006), Adult Attachment in the workplace (AAW) (Neustadt Chamorro-Premuzic, & Furnham, 2006) allows analyzing the quality of employee’ relations in the workplace using the Attachment Theory perspective (Bowlby, 1969). Both are considered an important aspect of comfort at work. We wish to test the effects of these two variables on the attachment dimension of affective commitment (Allen & Meyer, 1990). 240 subjects participated in the study. With the technique of multiple linear regressions, we estimated the impact of these two variables on affective commitment. The results show significant indications for Human Resource Management best practices.