How do prolonged wakefulness and alcohol

compare in thedecrements they produce on a

simulated driving task?

Professor: LiuStudent: Ruby

一、 Purpose

The scholars want to know performance in the driving simulator to impairments produced by several BAC stages.

二、 Solving the problem

To compare the effects of alcohol and prolonged wakefulness on driving performance.

三、 ReferencesYear Scholar Point

19951998

198819941990

Pack et al.US Department of TransportationMitler et al.Summala and Mikkol

aSchwing

When the driver falling asleep during

between 23:00, 3:00 and 7:00, and older driver in the mid afternoon always have the crashes.

1997 Dawson and Reid

To compare the performance decrements due to alcohol and

keep wakefulness.1. serial 19h wakefulness

performance=BAC of 0.05%2. serial 24h wakefulness

performance=BAC of 0.1%

三、 References

1997

1996

Dawson and Reid

Arnedt and MacLean

Compare the performance of two groups of subjects on a simulator.G1: alcohol (0.00, 0.05, 0.08%)

G2: prolong wakefulness (24:00, 02:30, 05:00 and 07:30)

Year Scholar Point

四、 Methods Subjects• 18 males• 19-35 years old• Standard of the subjects:Good health; non-smoking; driving license; regular sleep schedule; no evidence of alcohol and drug abuse; normal daytime sleepiness.• Drug and alcohol were prohibited before 48h

to the first test.• Avoiding caffeine ingestion before 24h to each

experimental days.

四、 Methods-Dependent Measures

• Stanford Sleepiness Scale (SSS)-Current level of sleepiness of a series of

descriptors.• Modified Stanford Scale (MSS)-

Current level of sleepiness of 24 questions and respond yes/no which identified two factors.1.An energic or activating factor2.Related to consciousness sleepiness and a loss of

control over remaining awake.

四、 Methods-Performance• Driving simulator1. 4 lane road2. Speed limits between 70-100

km/h3. Tester stays right hand lane4. There were no other car on the

road

四、 Methods-Performance• Dependent measure:1.Tracking-the deviation in feet of

the center.2.Tracking variability-S.D.3.Speed deviation-different between

the simulator and speed limit.4.Speed variability-S.D. 5.Off-road incidents

四、 Methods-Steps• 1h training session before 48 h on the

first day.• 3 experimental conditions (0.00, 0.05,

0.08%)3 test conditions at the same time-of-day (14:00, 17:00, 20:00) using Latin Square designs.

• The subjects can’t know the beverage concentration.

四、 Methods-Steps• On the experimental days, tester get

20min training session. • two 250-ml drinks containing either

only tonic water or tonic water mixed with 100% ethyl alcohol (USP).

• Alcohol were calculated the tester’s body water which is computed from the height, weight and age of each subject.

四、 Methods-Steps• 30min to drink the beverage.• Taking 30min break after drinking

then complete the SSS and the MSS, and drive 30min. Completing the SSS and MSS after driving.

• At the final of each test day, subjects have to fill the checklist which is about the beverage concentration. (testers didn’t believe that they were cheated by the beverage.)

五、 Results

五、 Results• Significant differences (increase

alcohol):1.Tracking variability increased2. speed deviation decreased (drove

faster)3. speed variability increased4. number of off-road increased

五、 Results• BAC 0.00-0.05%-tracking variability

and off-road events• BAC 0.00-0.08%- tracking variability,

speed variability and off-road events• BAC 0.05-0.08%- tracking variability

and off-road eventsPerformance decreased within the 30min driving. Time-of-day were absent.

五、 Results

六、 Discussion• Alcohol produce the impairment on

the driving simulator.• Alcohol has been found to produce

impairments on the psychomotor tasks (tracking and RT)

• Performance decreases in 30min driving test which is relative to alcohol and sleep loss.

六、 Discussion• After consuming alcohol have the

sleepiness at time 23:00-07:00, 14:00-17:00 and midnight which fatigue accidents are likely to occur during these times.