Novice drivers’ performance after different alcohol dosages and placebo in the divided-attention steering simulator (DASS)

Abstract

Rationale The divided-attention steering simulator (DASS) is designed to measure lane-keeping (i.e., a tracking task using a steering wheel) while performing a secondary visual task (responding to digits that appear in the corners of the computer screen). Some studies have already used the DASS, but the magnitude of impairment is difficult to interpret because reference values are lacking. Objective To examine the magnitude of impairment after administration of four different dosages of alcohol and placebo. Materials and methods Thirty-two healthy young adults participated in this randomized, single-blind crossover trial. Subjects received alcohol to gain a blood alcohol concentration (BAC) of 0.02%, 0.05%, 0.08%, and 0.10% or alcohol-placebo. Sixteen subjects performed a 30-min test in DASS (dual-task condition). Outcome measures were steering error, reaction time, and percentage of errors. Sixteen other subjects performed the test without performing the secondary peripheral task (single-task condition). Results Twenty-eight subjects (novice drivers; drivers' license up to 5 years) were included in the analyses. Dose-dependent impairment was found in both the singletask condition (F (4,11) =10.86, p<0.001) and the dual-task condition (F (4,9) =5.58, p<0.015). Performance at all BAC levels differed significantly (p<0.05) from alcohol-placebo, except BAC 0.02%. With increasing BAC levels, subjects made more errors and reacted slower on the peripheral visual search task, but these effects did not reach significance. Conclusion With increasing BAC, dose-dependent impairment was found. The DASS seems to be a suitable dividedattention task that is useful in psychopharmacological research and training of novice drivers.

An assessment of driving fitness in patients with visual impairment to understand the elevated risk of motor vehicle accidents

“…DSs, by removing the influence of driving technique as a confounding factor, provided a valuable opportunity to achieve this goal. Past studies have confirmed that DS systems are a powerful means of evaluating the effect on driving ability of alcohol,15 lack of sleep16 and drug use,17 as well as hemianopia18–20 and other visual field defects 21–26. Moreover, DSs have been found to compare favourably with on-road testing 27…”

Distraction produces over-additive increases in the degree to which alcohol impairs driving performance

“…lane exceedance). Alcohol impairs driving performance on each of these measures by increasing SDLP, steering rate, and the number of lane exceedances compared with sober driving performance (Marczinski et al 2008; Fillmore 2007; Harrison and Fillmore 2008; Harrison and Fillmore 2005; Rakauskas et al 2008; Shinar et al 2005; Verster et al 2009). These impairments are typically observed at BrACs at or above 0.08%.…”

The effects of energy drink in combination with alcohol on performance and subjective awareness

“…Koelega (1995) concluded that the effects on information processing and divided attention tasks are important because of their relevance to everyday life. Therefore, it is not surprising that alcohol impairs driving and driving-related skills (Holloway 1995; Starmer 1989; Verster et al 2009). The dose–response curve linking blood alcohol level and relative probability of causing a driving accident has long been established and applied in setting legal limits for alcohol levels and driving (Borkenstein et al 1964) with limits in Europe, US and UK currently set around 0.05–0.08% blood alcohol concentration (BAC) levels.…”