Continued Driving and Time to Transition to Nondriver Status through Error-Specific Driving Restrictions

ABSTRACT

We developed driving restrictions that are linked to specific driving errors, allowing cognitively impaired individuals to continue to independently meet mobility needs while minimizing risk to themselves and others. The purpose of this project was to evaluate the efficacy and duration expectancy of these restrictions in promoting safe continued driving. We followed 47 drivers age 60 years and older for 18 months, evaluating driving performance at 6-month intervals. Results demonstrated restricted drivers had safety profiles similar to safe drivers and gained additional driving time to transition to nondrivers.     

Sleepiness and Ethanol Effects on Simulated Driving

Twelve healthy young men were assessed in each of four experimental conditions presented in a Latin Square design: 8-hr time in bed (TIB) and placebo, 4-hr TIB and placebo, 8-hr TIB and ethanol, and 4-hr TIB and ethanol. After consuming ethanol (0.6 g/kg) or placebo (0900–0930 hr) with 20% supplements at 1030 and 1100 hr, subjects were tested for sleepiness (Multiple Sleep Latency Test at 1000, 1200, 1400, and 1600 hr) and divided attention (1030 hr) performance on day 1, and for simulated driving and divided attention (1000–1200 and 1400–1600 hr) performance on day 2. In the morning testing, with breath ethanol concentrations (BECs) averaging 0.049%, sleepiness was increased, divided attention reaction times increased (on both days), and simulated driving performance was disturbed in the ethanol and 4-hr TIB relative to placebo. Similarly in the afternoon, with BECs averaging 0.013%, the ethanol and 4-hr TIB condition increased sleepiness and disrupted divided attention and simulated driving performance. The results show that sleepiness and low-dose ethanol combine to impair simulated automobile driving, an impairment that extends beyond the point at which BEC reaches zero. They provide a possible explanation for the incidence of alcohol-related automobile accidents at low BECs.     

Driving as an Everyday Competence: A Model of Driving Competence and Behavior

Through a review of the literature on driving models, on models of everyday competence, and on older drivers, we developed a novel model of older drivers. Our proposed Driving as an Everyday Competence (DEC) model, which incorporates both driving competence and performance, was reviewed and critiqued by a group of experts. Our model suggests that the level of driving competence is determined by the interaction between individual and environment and is moderated by beliefs and awareness, leading to strategic level decisions regarding driving behaviors. Decisions made at the strategic, tactical, and operational levels must be viewed within the social/physical environmental context if driving performance is to be fully understood. The DEC model is a comprehensive model of older drivers and provides a foundation for the advancement of research on older drivers.     

Effects of Alcohol on Performance on a Distraction Task During Simulated Driving

Background:  Prior studies report that accidents involving intoxicated drivers are more likely to occur during performance of secondary tasks. We studied this phenomenon, using a dual-task paradigm, involving performance of a visual oddball (VO) task while driving in an alcohol challenge paradigm. Previous functional MRI (fMRI) studies of the VO task have shown activation in the anterior cingulate, hippocampus, and prefrontal cortex. Thus, we predicted dose-dependent decreases in activation of these areas during VO performance.
Methods:  Forty healthy social drinkers were administered 3 different doses of alcohol, individually tailored to their gender and weight. Participants performed a VO task while operating a virtual reality driving simulator in a 3T fMRI scanner.
Results:  Analysis showed a dose-dependent linear decrease in Blood Oxygen Level Dependent activation during task performance, primarily in hippocampus, anterior cingulate, and dorsolateral prefrontal areas, with the least activation occurring during the high dose. Behavioral analysis showed a dose-dependent linear increase in reaction time, with no effects associated with either correct hits or false alarms. In all dose conditions, driving speed decreased significantly after a VO stimulus. However, at the high dose this decrease was significantly less. Passenger-side line crossings significantly increased at the high dose.
Conclusions:  These results suggest that driving impairment during secondary task performance may be associated with alcohol-related effects on the above brain regions, which are involved with attentional processing/decision-making. Drivers with high blood alcohol concentrations may be less able to orient or detect novel or sudden stimuli during driving.     

Age-Related Differences in Risks of Drinking and Driving in Gender and Ethnic Groups

We examine the extent to which empirically observed age-related differences in rates of drinking and driving can be explained by concurrent differences in drinking patterns. Building on previous research showing significant age differences in drinking patterns between men and women and among three ethnic groups, Whites, Blacks, and Hispanics, our study considers whether there are unique gender and ethnic group differences in patterns of drinking and driving. Data were from 4395 respondents 12 to 80 years old in a general population survey of 20 urban areas in the United States. During the month preceding the interview, 1130 (25.7%) of all respondents had driven after having one or more drinks. Drinking pattern measures included drinking frequency, average drinking quantity, and the variance in the number of drinks consumed per occasion. To assess the relationships of drinking patterns to drinking and driving across age groups, two sets of analyses were conducted, one set in which age differences in drinking patterns were statistically controlled and one set in which they were not Although the statistical control for drinking patterns reduced age differences between gender and ethnic groups, it did not eliminate them. The reduction demonstrated that part of observed group differences in driving after drinking over age among gender and ethnic groups is due to age-related differences in drinking patterns. However, despite controlling drinking patterns young respondents remained more likely to drink and drive. A supplementary analysis of self-reported incidents of driving while intoxicated (i.e., driving after having five or mora drinks) further indicated that, controlling for drinking patterns, young respondents are most at risk.     

Alcohol Effects on Mood, Equilibrium, and Simulated Driving

BACKGROUND: The effects of alcohol on simple versus complex psychomotor performance were compared in 18 adults. METHODS: Subjects received ethanol doses of 0.0, 0.5, and 0.8 g/kg in a randomized, double-blind, within-subject design. Forty minutes after finishing their drinking, the subjects completed a 60-min battery of tests that included: 1) a sensory organization posturography test (EquiTest); 2) latency to apply the brake after appearance of a barrier in a driving simulator (brake reaction time); 3) visual analog subjective-effects scales (VAS); 4) the Profile of Mood States (POMS); 5) critical flicker fusion (CFF); and 6) choice reaction time (CRT). RESULTS: Alcohol dose dependently reduced composite equilibrium scores and increased brake reaction time. On the CRT task, total reaction time was significantly increased after the high dose but not the low dose. Alcohol dose dependently increased VAS "dizzy," "high," and "drug effect" ratings. The POMS and CFF were not significantly affected by alcohol. CONCLUSIONS: These data suggest that an ethanol dose that neither influences certain mood states nor impairs simple psychomotor task performance nonetheless may impair equilibrium and complex psychomotor tasks (e.g., driving).     

Type 1 Diabetes and Driving Experience: an Eight-year Cohort Study

The driving habits of 250 drivers with Type 1 diabetes were reviewed 8 years after a previous assessment. At least 45 patients had died and 18 patients could not be traced. A postal questionnaire of the 187 survivors elicited a response from 89%. Fifty-six patients (34%) still held an unrestricted driving licence, demonstrating that a significant proportion of diabetic drivers had not declared diabetes to the licensing authority and/or their motor insurer and continued to ignore the statutory regulations. Fewer patients held Heavy Goods Vehicle licences than 8 years previously. Twenty-four patients had ceased driving as their driving skills had diminished with advancing age and ill health. This was a voluntary decision by all but two patients whose driving licences had been revoked. Thirty-nine patients admitted to a total of 55 road traffic accidents since 1979; 9 accidents (16%) were attributed to hypoglycaemia. Although dependent on patients' honesty and the accuracy of recall, the disclosed accident rates of 4.9 per million miles driven for male drivers and 6.3 per million miles for female drivers are comparable to the accident rate of a non-diabetic driving population of similar age.     

睡眠呼吸暂停低通气综合征对飞行人员驾驶能力的影响探讨

睡眠呼吸暂停低通气综合征因其夜间间歇性缺氧及睡眠片断化导致白日嗜睡,注意力、操纵能力以及执行能力等脑功能的下降,从而影响飞行驾驶员驾驶能力,是飞行安全的潜在危险。本文通过检索国内外相关文献,分析睡眠呼吸暂停综合征对脑功能的影响因素,进一步阐述睡眠呼吸暂停对飞行人员驾驶能力影响的危害。     

Driving Behavior of Alcohol,Cannabis, and Cocaine Abuse Treatment Clients and Population Controls

Background/Introduction: A paucity of research exists on driving after use of cannabis or cocaine among clients in substance abuse treatment and changes in this behavior after treatment. Objectives: The objectives of this research are to compare treatment clients and population controls before and after treatment in terms of: 1) amount of driving; 2) alcohol, cannabis, and cocaine consumption; 3) driving after use of alcohol, cannabis, and cocaine; and 4) driving infractions. Method: Telephone interviews were conducted with a sample of 110 clients who received treatment in 1995 for a primary problem of alcohol (n = 44), cannabis (n = 37), or cocaine (n = 29) abuse. A random sample of 104 drivers from the general population, frequency matched by age and sex was also interviewed. Participants were asked to describe their driving habits and driving infractions before and after 1995. Results: Both treatment and control groups reported about the same amount of driving. The treatment group reported significantly more consumption of alcohol, cannabis, and cocaine than did the control group before treatment. Significant declines in use for each substance were found for the treatment group after treatment, but use for the control group remained stable over the two time periods. Similarly significant declines in driving after use of alcohol, cannabis, and cocaine were found for the treatment group but the control group remained stable. Finally driving infractions, including speeding tickets, collisions, and license suspensions, significantly declined for the treatment group but not the control group. Discussion: The results confirm that before treatment, the treatment subjects drove more frequently after consuming alcohol, cannabis, or cocaine than the control group. Declines in substance use and driving after treatment were accompanied by reductions in some types of driving infractions. Differences between groups, and over time in terms of driving while under the influence of psychoactive substances better explain the results than differences between groups in impulsivity/risk‐taking or sleep problems.     

Disruptions in Functional Network Connectivity During Alcohol Intoxicated Driving

Background: Driving while under the influence of alcohol is a major public health problem whose neural basis is not well understood. In a recently published functional magnetic resonance imaging (fMRI) study ( Meda et al., 2009 ), our group identified 5, independent critical driving‐associated brain circuits whose inter‐regional connectivity was disrupted by alcohol intoxication. However, the functional connectivity between these circuits has not yet been explored in order to determine how these networks communicate with each other during sober and alcohol‐intoxicated states. Methods: In the current study, we explored such differences in connections between the above brain circuits and driving behavior, under the influence of alcohol versus placebo. Forty social drinkers who drove regularly underwent fMRI scans during virtual reality driving simulations following 2 alcohol doses, placebo and an individualized dose producing blood alcohol concentrations (BACs) of 0.10%. Results: At the active dose, we found specific disruptions of functional network connectivity between the frontal‐temporal‐basal ganglia and the cerebellar circuits. The temporal connectivity between these 2 circuits was found to be less correlated (p < 0.05) when driving under the influence of alcohol. This disconnection was also associated with an abnormal driving behavior (unstable motor vehicle steering). Conclusions: Connections between frontal‐temporal‐basal ganglia and cerebellum have recently been explored; these may be responsible in part for maintaining normal motor behavior by integrating their overlapping motor control functions. These connections appear to be disrupted by alcohol intoxication, in turn associated with an explicit type of impaired driving behavior.