Complexité des situations, expérience, tension et vigilance : quels impacts sur la charge de travail et les performances de jeunes conducteurs ?

The aim of this thesis is to identify the links between factors contributing to accidents among young drivers, by analyzing the effects of situation complexity and driving experience on workload, tension, vigilance and performance. The general hypothesis is that costly situations, i.e. simple and very complex, and the lack of experience can lead to high energy expenditure. A high level of tension and a low level of vigilance can thus result in performance impairments through the increase of workload, characterizing a driver's overload. This should be observed earlier for novices who had a Traditionally-Trained Learning (TTL), then for those who had an Early-Trained Learning (ETL), then for drivers arriving at the end of the probationary period, and finally for more experienced drivers. A first experiment carried out on subjective data has confirmed the links between the levels of workload, tension and vigilance depending on the situation complexity. However, only novices ETL were overloaded with the situation complexity, due to ineffective strategies. A second experiment carried out on subjective and physiological data has also confirmed the links between the levels of workload, tension and vigilance, with an underestimation of the physiological level by the novices TTL. The two compared groups (novices TTL and drivers at the end of the probation) were overloaded in complex situation, either because they didn't adopt the appropriate strategies (novices TTL), either by lack of flexibility in relation to the automatisms (drivers at the end of the probation). The results establishing the links between the characteristics of the driving situation and the individual characteristics leading to road accidents will allow adapting awareness actions and modules of driving training.L'objectif de cette thèse est d'identifier les liens entre les facteurs accidentogènes chez les jeunes conducteurs, en analysant les effets de la complexité de la situation et de l'expérience de conduite sur la charge de travail, la tension, la vigilance et les performances. L'hypothèse générale est que les situations coûteuses, i.e. simples et très complexes, ainsi que le manque d'expérience peuvent mener à une forte dépense énergétique. Ainsi, un haut niveau de tension et un faible niveau de vigilance peuvent provoquer des dégradations de performances à travers la hausse de la charge de travail, caractérisant une surcharge du conducteur. Ceci devrait s'observer plus précocement pour les novices ayant suivi un Apprentissage Traditionnel (AT), puis pour ceux ayant suivi un Apprentissage Anticipé de la Conduite (AAC), puis pour les conducteurs arrivant à la fin du permis probatoire, et enfin pour les plus expérimentés. Une première expérimentation menée sur des données subjectives a confirmé les liens entre les niveaux de charge de travail, de tension et de vigilance en fonction de la complexité de la situation. Cependant, seuls les novices AAC étaient surchargés avec la complexité de la situation, de part des stratégies inefficaces. Une seconde expérimentation menée sur des données subjectives et physiologiques a également confirmé les liens entre les niveaux de charge de travail, de tension et de vigilance, avec une sous-estimation du niveau physiologique par les novices AT. Les deux groupes comparés (novices AT et conducteurs à la fin du permis probatoire) étaient surchargés en situation complexe, soit car ils n'adoptaient pas les stratégies adéquates (novice), soit par manque de flexibilité par rapport aux automatismes (conducteurs à la fin du permis probatoire). Les résultats établissant les liens entre des caractéristiques de la situation de conduite et des caractéristiques individuelles menant à des accidents de la route pourront permettre d'adapter les actions de sensibilisation et les modules de formations à la conduite

Overload depending on driving experience and situation complexity: which strategies faced with a pedestrian crossing?

The purpose of this study was to identify the influence of situation complexity and driving experience on subjective workload and driving performance, and the less costly and the most effective strategies faced with a hazard pedestrian crossing. Four groups of young drivers (15 traditionally trained novices, 12 early-trained novices, 15 with three years of experience and 15 with a minimum of five years of experience) were randomly assigned to three situations (simple, moderately complex and very complex) including unexpected pedestrian crossings, in a driving simulator. The subjective workload was collected by the NASA-TLX questionnaire after each situation. The main results confirmed that the situation complexity and the lack of experience increased the subjective workload. Moreover, the subjective workload, the avoidance strategies and the reaction times influenced the number of collisions depending on situation complexity and driving experience. These results must be taken into account to target the prevention actions

Divided-attention task on driving simulator: comparison among three groups of drivers

Introduction: Driving is a complex and dynamic task that requires performing simultaneously several sub-tasks, as traffic management and vehicle control. Driving involves both automatic and controlled processing depending on situation met and drivers’ experience. Method: Three groups of drivers with different driving experience were submitted to a divided-attention task in order to assess the interference linked to a secondary task on driving behaviour. The main task was a car-following task and the secondary task was a number identification task which could appear on central or peripheral vision. Results and discussion: Results showed that driving performances increase with experience. Indeed, novice drivers, compared to more experienced drivers, took more time to brake and had more difficulties to maintain a stable position in the lane. This task allowed to differentiate driving behaviour depending on experience and could be used in training of novice drivers

ALCOol, vigiLAnce, Charge de travail : facteurs d'accident chez les jeunes conducteurs. Rapport intermédiaire N°1

Convention 2013/MP/03 - Fondation Sécurité routièreL’âge et le sexe des conducteurs représentent les principaux facteurs d’implication dans les accidents [source ONISR, 2011]. Les études épidémiologiques montrent ainsi que les jeunes ont une probabilité d'être impliqués dans un accident largement plus importante que celle des autres conducteurs à l'exclusion des conducteurs les plus âgés et les jeunes conducteurs masculins âgés de moins de 24 ans présentent un risque plus élevé d’accidents. De plus, les statistiques mensuelles d’accidents après l’obtention du permis de conduire montrent que le taux initial très élevé d’accidents décroît rapidement pendant les premiers mois de conduite. Par ailleurs, d’après le modèle de courbe en U renversé d’Ansseau et Timsit-Berthier, le niveau de performance augmente avec celui de la vigilance jusqu’à un optimum, au-delà de cet optimum l’augmentation de la vigilance entraîne au contraire une baisse de la performance. L’excès de vigilance que représentent le stress ou l’hyperexcitation a un pouvoir de dégradation plus rapide sur les activités complexes que sur les activités les plus simples. Il y a donc un niveau optimal de vigilance pour chaque type de tâche réalisée et la dégradation de la performance peut être liée à de l’hypovigilance ou de l’hypervigilance. La charge de travail est ainsi également en lien avec la vigilance. Une augmentation de cette charge entraîne en effet une hausse de la vigilance mais la tendance s’inverse lorsque les tâches difficiles et précises entraînent une surcharge, avec dans ce cas une diminution de la vigilance. De plus, lorsque la tension reflétant l’évaluation du danger relatif aux activités [Thayer, 1989 ; in Kosćec & Radosević-Vidacek, 2004] est élevée, cela entraîne une hausse de la charge de travail subjective [Ucelli et al., 2011] et une baisse de vigilance [Thayer, 1986]. L’objet du travail est donc de manipuler ces facteurs de variations de la vigilance afin d’estimer en quoi leurs effets peuvent s’avérer délétères sur la conduite, notamment chez de très jeunes conducteurs novices

Divided-attention task on driving simulator: comparison among three groups of drivers

ABSTRACT Introduction: Driving is a complex and dynamic task that requires performing simultaneously several sub-tasks, as traffic management and vehicle control. Driving involves both automatic and controlled processing depending on situation met and drivers' experience. Method: Three groups of drivers with different driving experience were submitted to a divided-attention task in order to assess the interference linked to a secondary task on driving behaviour. The main task was a carfollowing task and the secondary task was a number identification task which could appear on central or peripheral vision. Results and discussion: Results showed that driving performances increase with experience. Indeed, novice drivers, compared to more experienced drivers, took more time to brake and had more difficulties to maintain a stable position in the lane. This task allowed to differentiate driving behaviour depending on experience and could be used in training of novice drivers

Situations complexity, experience, tension and vigilance : which impact on workload and performance of young drivers?

L'objectif de cette thèse est d'identifier les liens entre les facteurs accidentogènes chez les jeunes conducteurs, en analysant les effets de la complexité de la situation et de l'expérience de conduite sur la charge de travail, la tension, la vigilance et les performances. L'hypothèse générale est que les situations coûteuses, i.e. simples et très complexes, ainsi que le manque d'expérience peuvent mener à une forte dépense énergétique. Ainsi, un haut niveau de tension et un faible niveau de vigilance peuvent provoquer des dégradations de performances à travers la hausse de la charge de travail, caractérisant une surcharge du conducteur. Ceci devrait s'observer plus précocement pour les novices ayant suivi un Apprentissage Traditionnel (AT), puis pour ceux ayant suivi un Apprentissage Anticipé de la Conduite (AAC), puis pour les conducteurs arrivant à la fin du permis probatoire, et enfin pour les plus expérimentés. Une première expérimentation menée sur des données subjectives a confirmé les liens entre les niveaux de charge de travail, de tension et de vigilance en fonction de la complexité de la situation. Une seconde expérimentation menée sur des données subjectives et physiologiques a également confirmé les liens entre les niveaux de charge de travail, de tension et de vigilance, avec une sous-estimation du niveau physiologique par les novices AT. Les résultats établissant les liens entre des caractéristiques de la situation de conduite et des caractéristiques individuelles menant à des accidents de la route pourront permettre d'adapter les actions de sensibilisation et les modules de formations à la conduite.The aim of this thesis is to identify the links between the accidents factors among young drivers, by analyzing the effects of situation complexity and driving experience on workload, tension, vigilance and performance. The general hypothesis is that costly situations, i.e. simple and very complex, and the lack of experience can lead to a high energy expenditure. Thus, a high level of tension and a low level of vigilance can provoke performance impairments through the increase of workload, which characterizes an overload of the driver. This should be early observed for novices who had a traditional learning, then for early-trained novices, then for drivers arriving at the end of the probationnary period, and then for the most experienced ones. A first experiment, carried out on subjective data, has confirmed the links beween the levels of workload, tenion and vigilance depending on situation complexity. A second experiment, carried out on subjective and physiological data, has also confirmed the links between the levels of workload, tension and vigilance, with an underestimation of the pysiological level by the traditionally trained novices. The results establishing the links between the driving situation's characteristics and the individuals' characteristics leading to road accidents will allow adapting the awareness actions and the modules of driving trainings

Does driving experience delay overload threshold as a function of situation complexity? In L. Dorn & M. Sullman (Eds.). Driver Behaviour and Training VI

The present study aimed to identify overload threshold due to driving situation complexity and driving practice. Moreover, subjective levels of tension [mental stress] and vigilance were analyzed as they can respectively influence workload and performance. Material & Methods: Thirty-two participants [9 novices aged between 18-20 who obtained their driving license within the last two months, 9 drivers aged 21 arriving at the end of the three-year probationary period, and 14 drivers aged between 23-30 with at least five years of experience] were randomly assigned to three situations with different levels of complexity [22.5 kms each] in a driving simulator. The less complex situation consisted in a straight national road, without any traffic. The moderately complex situation included right and left curves. The most complex situation had double and sharper curves, with oncoming traffic. In each situation, three pedestrians crossed the road in front of the participants. Self-reported levels of tension, vigilance and workload were collected by questionnaires between each driving situation. Objective driving performance [number of collisions with pedestrians] was also analyzed. First analyses showed that overload threshold is earlier for novice drivers than for more experienced drivers. Indeed, the number of collisions with pedestrians, subjective levels of workload and tension were significantly higher for novice drivers. Nevertheless, drivers with three years of experience had significantly lower number of collisions with pedestrians, subjective levels of workload and tension, and higher subjective vigilance than drivers with at least five years of experience. It thus seemed that overload threshold arrives earlier for the most experienced drivers than for drivers with three years of driving experience. Situation complexity didn't reduce overload threshold depending on driving experience

Measuring mental workload with the NASA-TLX needs to examine each dimension rather than relying on the global score: An example with driving

The distinction between several components of mental workload is often made in the ergonomics literature. However, measurements used are often established from a global score, notably with several questionnaires that originally reflect several dimensions. The present study tested the effect of driving situation complexity, experience and subjective levels of tension and alertness on each dimension of the NASA-TLX questionnaire of workload, in order to highlight the potential influence of intrinsic, extraneous and germane load factors. The results showed that, in complex situation, mental, temporal and physical demand (load dimensions) increased, and that novice drivers presented high physical demand when subjective tension was low and low own performance. Moreover, increase of mental and physical demand increased effort. It thus appears essential to distinguish the different components of mental workload used in the NASA-TLX questionnair

Complexité de la situation et de l’expérience de conduite : quels impacts sur les mesures objectives et subjectives de charge de travail?

En situations simples et très complexes et avec le manque d’expérience représenté par peu d’automatisation de la tâche, les niveaux objectifs et subjectifs de charge de travail devraient augmenter. Le niveau physiologique de charge de travail était plus élevé pour les novices que pour les expérimentés, notamment en situation très complexe

Effects of situation complexity and driving experience on performance through subjective and objective tension

The aim of the present paper is to identify the effect of situation complexity and driving experience on performance through subjective and objective levels of tension. The main contribution of this paper to the Cognitive Ergonomics field consists in the identification of accidents’ factors of young drivers faced to a stressful event. Thirty-two drivers (16 novices vs. 16 more experienced) were randomly assigned to three levels of situation complexity (simple, moderately complex and very complex) in a driving simulator. Physiological and subjective levels of tension were respectively associated to “pedestrian crossings” events and to the whole situations. Driving performance corresponded to reaction times and to collisions’ number with the pedestrians. Results showed that novice drivers had weaker performance than the more experienced once, even though their high level of objective and subjective tension due to situation complexity improved their performance. Therefore, target driving assistance systems to deal with hazard events could reduce road accidents among young novice drivers