2.?Defining DrowsinessThe term ��drowsy�� is synonymous with sleepy, which simply means an inclination to fall asleep. The Diabete stages of sleep can be categorized as awake, non-rapid eye movement sleep (NREM), and rapid eye kinase inhibitor U0126 movement sleep (REM). The second stage, NREM, can be subdivided into the following three stages [17]:Stage I: transition from awake to asleep (drowsy)Stage II: light sleepStages III: deep sleepIn order to analyze driver drowsiness, researchers have mostly studied Stage I, which is the drowsiness phase.

Inhibitors,Modulators,Libraries The crashes that occur due to driver drowsiness have Inhibitors,Modulators,Libraries a number of characteristics [18]:Occur late at night (0:00 am�C7:00 am) or during mid-afternoon (2:00 pm�C4:00 pm)Involve a single vehicle running off the roadOccur on high-speed roadwaysDriver is often aloneDriver is often a young male, 16 to 25 years oldNo skid marks or indication of brakingIn relation to these characteristics, the Southwest England and the Midlands Police databases use the following criteria to identify accidents that are caused by drowsiness [5]:Blood alcohol level below the legal driving limitVehicle ran off the road or onto the back of another vehicleNo sign of brakes being appliedVehicle has no mechanical defectGood weather conditions and clear visibilityElimination of ��speeding�� or ��driving too close to the vehicle in front�� as potential causesThe police officer at the scene suspects sleepiness as the primary causeStatistics derived using these criteria cannot account fully for accidents caused by drowsiness because of the complexity involved; therefore, accidents that can be attributed Inhibitors,Modulators,Libraries to Inhibitors,Modulators,Libraries driver drowsiness may be more devastating Inhibitors,Modulators,Libraries than the statistics reveal.

Hence, in order to avoid these types of accidents, it is necessary to derive Inhibitors,Modulators,Libraries Inhibitors,Modulators,Libraries effective measures to detect driver drowsiness and alert the driver.3.?Simulated Environment for Drowsiness ManipulationIt is not safe and ethical to make a drowsy driver drive on road. Hence, researchers have used simulated environments to carry out their experiments. Experimental control, efficiency, Inhibitors,Modulators,Libraries low cost, safety, and ease of data collection are the main advantages of using simulators [19,20].

The driving simulators can be broadly classified as: (1) Low-level simulators (Figure 1(a)) consisting of a computer, a monitor, a realistic cockpit, a steering Drug_discovery wheel, manual gear box and pedals (clutch, brake and accelerator); (2) Mid-level (Fixed-base) simulators (Figure 1(b)) comprising Anacetrapib of advanced imaging techniques, a large projection screen, a realistic car, and possibly a simple motion base and (3) High-level (Motion-based) simulators (Figure 1(c)) typically providing a view close to 360�� and an extensive moving base [21].Figure 1.(a) MiniSim; (b) NADS 2; (c) NADS 1. Reproduced with permission from Site URL List 1|]# (Mini Sim: http://news-releases.uiowa.edu/2010/april/041210mini-sim.