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

Abstract

Rationale Research indicates that alcohol intoxication and increased demands on drivers’ attention from distractions (e.g. passengers and cell phones) contribute to poor driving performance and increased rates of traffic accidents and fatalities. Objectives The present study examined the separate and combined effects of alcohol and distraction on simulated driving performance at blood alcohol concentrations (BrACs) below the legal driving limit in the United States (i.e. 0.08%). Methods Fifty healthy adult drivers (36 men and 14 women) were tested in a driving simulator following a 0.65 g/kg dose of alcohol and a placebo. Drivers completed two drive tests; a distracted drive, which included a two-choice detection task, and an undistracted control drive. Multiple indicators of driving performance, such as drive speed, within-lane deviation, steering rate, and lane exceedances were measured. Results Alcohol and distraction each impaired measures of driving performance. Moreover, the magnitude of alcohol impairment was increased by at least two-fold when tested under the distracting versus the undistracted condition. Conclusions The findings highlight the need for a clearer understanding of how common distractions impact intoxicated drivers, especially at BrACs that are currently legal for driving in the United States.

Laboratory analysis of risky driving at 0.05% and 0.08% blood alcohol concentration

“…It is recognized that this situation is somewhat simplistic given that everyday driving also requires individuals to simultaneously contend with a multitude of distractions, such as numerous dashboard controls, passengers in the vehicle, and cellular telephones. Laboratory research has shown these forms of distraction impair driving skill, especially in drivers under the influence of alcohol (e.g., Harrison and Fillmore, 2011; Rakauskas et al, 2008; Van Dyke and Fillmore, 2015). At present it is unclear how such distracting or high demand driving environments might affect drivers’ proclivity for risk-taking, and the degree to which alcohol might increase such risky driving.…”

“…Drivers were penalized $0.50 for each crash. This response conflict scenario is designed to mimic everyday driving behaviors in which drivers are rewarded by arriving at their destination on time at the cost of potential traffic citations, and has been successfully used in other research in our laboratory (e.g., Van Dyke and Fillmore, 2015; Fillmore et al, 2008). …”

Effects of Age and Acute Moderate Alcohol Administration on Neurophysiology During Simulated Driving

“…For instance, our simulator protocol lacked distractors common in typical driving contexts including passengers, radio, phone calls, and texting. Performance of younger drivers under distractor conditions has been demonstrated to be particularly susceptible to disruption by moderate alcohol doses (Harrison and Fillmore, ; Van Dyke and Fillmore, ). A simulation containing such distraction might alter the observed patterns of neural alteration.…”

The influence of groups and alcohol consumption on individual risk-taking

“…Where research has considered both performance and risky driving in the same study, driving skill appears to be impaired and risk-taking elevated following alcohol consumption, compared to a placebo beverage (Laude & Fillmore, 2015;Van Dyke & Fillmore, 2015). Further highlighting this distinction, other work (Berthelon & Gineyt, 2014; E. L. R. Harrison & Fillmore, 2011;Veldstra et al, 2012) has revealed an effect of alcohol only on driving skill, and not risky driving.…”

“…As such, participants may consider running a red light to be appealing, yet by doing so participants run the risk of a collision which would cost more time (Chein, Albert, O'Brien, Uckert, & Steinberg, 2011). Moreover, in previous studies (e.g., E. L. R. Harrison & Fillmore, 2011;Laude & Fillmore, 2016;Van Dyke & Fillmore, 2015) a clear distinction is made between measurement of impaired driving skills (e.g., lane deviation) and risky or reckless driving (e.g., driving through a red light). This suggests that the contribution of alcohol towards drink-driving-related incidents is complex, as intoxication affects multiple associated behaviours (e.g., driving skill, motor coordination and risk-taking behaviour).…”