It has also been demonstrat- ed in post-crash interviews that night driving, prior sleep .... Post delineators are placed in relation to the edge of the road. Table 1.
Original Article
Industrial Health 2009, 47, 393–401
The Effects of Driving Situation on Sleepiness Indicators after Sleep Loss: A Driving Simulator Study Anna ANUND1, 2*, Göran KECKLUND3, Albert KIRCHER2, Andreas TAPANI2 and Torbjörn ÅKERSTEDT1, 3 1Clinical
Neuroscience, Karolinska Institute, SE-177 71 Stockholm, Sweden Road and Transport Research Institute, Olaus Magnus vag 35, SE-581 95 Linköping, Sweden 3Stress Research Institute, Stockholm University, 10691 Stockholm, Sweden 2Swedish
Received December 18, 2008 and accepted March 6, 2009
Abstract: Almost all studies of sleepy driving are carried out in driving simulators and with monotonous road conditions (no interaction with other cars). The present study investigated indicators of sleepy driving in a more challenging scenario after a night awake. 17 participants drove a high fidelity moving base driving simulator experiment while sleepiness was monitored physiologically and behaviourally. Short periods of situations of free driving (no other vehicles) alternated with short periods of following another vehicle (car following) with and without the possibility to overtake. The result showed that a night of prior sleep loss increased sleepiness levels at the wheel (eye closure duration and lateral variability) compared to after a night of normal sleep. Blink duration while overtaking was significantly lower compared to the other situations, it was at the same level as after night sleep. Speed when passing a stopped school bus was not significantly affected by sleepiness. However the warning caused a more rapid reduction of speed. In conclusion, a moderately challenging driving contest did not affect sleepiness indicators, but a very challenging one did so (overtaking). This suggests that it is important to monitor the driving situation in field operational tests of sleepy driving. Key words: Sleepy drivers, Complex scenario, Physiological indicators, Driving behaviour, Driving simulator study
Introduction Sleep related crashes have received increasing attention during the latest decade. The National Transportation and Safety Board (US) has pointed out that sleepiness while driving is one of the most important contributing factors for road crashes1). Epidemiological studies based on selfreports or in-depth crash investigations show much higher figures compared to official crash statistics and suggest that about 10 to 20 percent of all crashes might be sleep or fatigue related2–5). It has also been demonstrated in post-crash interviews that night driving, prior sleep
