1G-35 Changes of driving performance and skin conductance level of experienced taxi drivers due to distraction tasks

Abstract

Introduction Recently, there has been a rise in the vehicular use of electronic equipment, such as mobile phones and navigation systems. During driving, mobile phones are necessary communication tools and/or sometimes important contact tools in an emergency situation. Navigation systems not only provide path-finding information but also music, movie, and digital multimedia broadcasting (DMB) services. Navigation systems also increase driving convenience by providing real-time road and traffic information. While the use of in-vehicle electronics can increase the quality of the driving experience, it is conversely possible that the additional information can increase the drivers' workload and/or decrease the driver's attention, which could result in serious problems such as increased accidents [1, 2]. Numerous studies have been undertaken to evaluate the effects of performing a task or disruption of attention on driving. Use of a mobile phone or navigation system during driving increases average following distance, decreases average car speed, and increases variability of car speed [3,4,5,6]. Furthermore, mobile phone or navigation system use increases driver workload and influences the stress or tension experienced by the driver. These results activated sympathetic nervous system and increased heart rate and Skin Conductance Level (SCL) [7,8,9]. Driving performance is influenced by a combination of human, vehicular, and environmental factors. Due to a flaw in one or more one of these factors, accidents occur where the main cause is most often due to the human factor [10]. Accidents due to human factor occur when the driver is inexperienced or careless [11]. Driving is a complicated act requiring focused attention by the driver; secondary tasks performed driving result can impede driving ability [12]. Previous studies reported that driver distraction due to additional workload can trigger driver mistakes [3,4,5,6,7,8,9]. However, these studies were performed to young adults with a short driving experience and little studies for experienced drivers with sufficient driving experience. Since driving performance is influenced by driving experience, further knowledge is needed to clarify the effects of distraction on driving performance. This study was undertaken to investigate the effects of distraction on driving performance of experienced taxi drivers aged in their 50s. Distraction tasks used in Abstract This study investigated the effects of distraction tasks, such as Sending Text Message (STM) task with cellphone and Searching Navigation (SN) task with car navigation system, on driving performance and Skin Conductance Level (SCL) of experienced taxi drivers. Twelve male taxi drivers (age 56.3±4.4 years, taxi driving experience 28.4±6.4 years) and fourteen female taxi drivers (age 55.5±3.5 years, taxi driving experience 19.4±5.0 years) were instructed to drive at a constant speed (90 km/hr) for 2 min while keeping a distance of 30 m from the front car also running at a speed of 90 km/hr.