Das Führen eines Kraftfahrzeugs unter Doppeltätigkeitsbelastung: Alternsbedingte Leistungsunterschiede in Gefahrensituationen

摘要

Dual task situations are ubiquitous, at home as well as at work. Especially modern information technologies often require the coordination of different activities. For example, while driving a car the driver has to process additional information (e.g. from the navigation system, from the walkie-talkie or from the mobile phone) and to react in an appropriate way. This is especially the case for professional drivers like taxi drivers or lorry drivers. Under less demanding driving conditions, e.g. slow driving with low traffic density, the coordination of the primary task (driving the car) and the secondary task (manipulating the navigation system) might be relatively easy. However, under demanding driving conditions and especially in critical traffic situations, impairments in reaction times and driving errors can be expected. Dual task conditions are in particular demanding for older drivers as has been demonstrated in many experimental studies. Another important factor is the cross-task compatibility that is whether the information presented in the second task provides information, which is compatible or incompatible to the primary task. In first experiments using a driving simulation set-up we tested groups of younger (age: 18-30 years) and elderly (age: 56 - 65 years) drivers in their reaction times and error rates in dangerous situations (a person suddenly jumping on the street, which requires a sudden reaction with the steering wheel). First results indicate that effects of cross-task compatibility depend on the relevance of the driving situation and on the direction of the response that has to be performed in the primary task and not so much on the position at which the information is presented. Moreover, although the groups of elderly participants show increased reaction times they do not seem to be especially impaired by compatibility effects. This finding might be a result of the increased amount of expertise in older drivers. The study examines with younger and elderly professional drivers whether and how driving is impaired by dual-task demands, especially in critical situations. Based on the findings we plan to propose guidelines and recommondations for the age-based design of operation devices in vehicles and to suggest training programms for older drivers.%Doppeltätigkeiten stellen insbesondere für ältere Kraftfahrer deutliche Belastungen dar. So muss beispielsweise ein Fahrzeugführer während des Fahrens zusätzliche Informationen (z. B. des Navigationssystems) aufnehmen und gegebenenfalls auf sie reagieren. Bei ungünstigen Verkehrsbedingungen ist dann mit Einbußen der Reaktionsfähigkeit auf kritische Verkehrssituationen zu rechnen. Die Belastungen hängen auch davon ab, ob die Zweitaufgabe zur auszuführenden Reaktion in der Erstaufgabe kompatible oder inkompatible Informationen bereitstellt. Erste Ergebnisse deuten darauf hin, dass die Wirksamkeit der Kompatibilitätsbeziehung von der Bedeutung der Verkehrssituation und von der Richtung der auszuführenden Reaktion abhängt und nicht allein durch den Präsentationsort der reaktionsrelevanten Information determiniert wird.