Driver Self-regulation Research Articles

Self-Regulation of Driving Behavior Under the Influence of Cannabis: The Role of Driving Complexity and Driver Vision

This study analyzed the self-regulation behaviors of drivers under the influence of cannabis and its relationship with road complexity and some driver traits, including visual deterioration. Cannabis is the illicit drug most often detected in drivers; its use results in significant negative effects in terms of visual function. Self-regulation behaviors involve the mechanisms used by drivers to maintain or reduce the risk resulting from different circumstances or the driving environment. Thirty-one young, occasional cannabis users were assessed both in a baseline session and after smoking cannabis. We evaluated the visual function (visual acuity and contrast sensitivity) and driver self-regulation variables of both longitudinal and lateral control as the speed adaptation and standard deviation of lateral position (SDLP). Visual function was significantly impaired after cannabis use. Recreational cannabis use did not result in self-regulation, although some road features such as curved roads did determine self-regulation. Male participants adopted mean faster driving speeds with respect to the speed limit. Driver age also determined better lateral control with lower SDLPs. In addition, visual impairment resulting from cannabis use (contrast sensitivity) was linked with self-regulation by changes in longitudinal and lateral control. Contrast sensitivity could be a good indicator of individual visual status to help determine how drivers self-regulate their driving both in normal conditions and while under the influence of cannabis. The findings provide new insights about driver self-regulation under cannabis effects and are useful for policy making and awareness campaigns.

Driver Self-Regulation Practices in Older Drivers with and Without Mild Cognitive Impairment.

ObjectiveTo assess the impact of cognitive, socio-demographic and driving-related characteristics on self-regulation practices in older drivers with mild cognitive impairment (MCI) (determined by the Telephone Cognitive Screen (T-CogS) score), compared with drivers with no cognitive impairment.Design, Setting, ParticipantsA cross-sectional study collected information from 362 drivers with MCI and 611 drivers with no cognitive impairment, who were aged 65+ years, and were living in Western Australia between November 2018 and February 2019.MeasurementsSelf-reported self-regulation driving practices.ResultsThe majority of drivers with MCI (62.4%) and those with no cognitive impairment (57.1%) reported self-regulating their driving in at least one situation, in the past three months. The most common situations that both groups of drivers self-regulated in were “driving at night in the rain”, “parallel parking”, and “driving when raining”. Drivers with MCI were only significantly more likely to self-regulate when “making turns across oncoming traffic” and “driving at night”. They also had 39% greater odds of self-regulating in at least one driving situation, compared with drivers with no cognitive impairment (OR: 1.39, 95% CI=1.04–1.85, p=0.02). Females also had 2.3 times greater odds of self-regulating (OR=2.34, 95% CI=1.76–3.12, p<0.001). Drivers aged 75+ years had 1.6 times greater odds of self-regulating, compared with drivers aged 65–69 years (OR=1.58, 95% CI=1.12–2.23, p=0.01).ConclusionOlder drivers with MCI were more likely to self-regulate their driving, compared to drivers with no cognitive impairment, particularly in complex driving situations. This suggests that some drivers with MCI may be able to recognize their cognitive limitations and adjust their driving accordingly. However, several drivers with MCI, particularly males, did not self-regulate their driving. This highlights the importance of advising patients about the impact of MCI on driving ability, suitable self-regulation strategies, as well as monitoring their driving ability.

Mobile phone conversation distraction: Understanding differences in impact between simulator and naturalistic driving studies

A current issue within the driver distraction community centres around different findings regarding the impact of mobile phone conversation on driving found in driving simulators versus instrumented vehicles employed in real-world naturalistic driving studies (NDSs). This paper compares and contrasts the two types of studies and aims to provide reasons for the differences in findings that have been documented. A comprehensive review of literature and consultations with human factors experts highlighted that simulator studies tend to show degradation in driving performance, suggestive of increased crash risk as a result of mobile phone conversation. Whilst NDSs, at times, present data suggesting that mobile phone conversation distraction actually reduces crash risk. This study identifies that these differences may be attributed to behavioural hypotheses associated with driver self-regulation, arousal from cognitive loading, task displacement and gaze concentration – all of which need to be explicitly tested in future driving studies.Metric estimation and application was also revealed to be polarising results and the subsequent assessment of the crash risk. A common metric applied in this domain is the ‘Odds Ratio’, particularly prevalent in NDSs. This study presents a detailed investigation into the assumptions and application of the Odds Ratio which revealed the potential for over- and under-estimation of the metric depending on the core data and sampling assumptions. Furthermore, this research presents a comparative analysis of select driving simulator studies and an NDS considering only driving behaviour data as a means to consistently compare the findings of both methodologies. The findings from this investigation implores the need for greater consistency in the application of analysis methods and metrics across both simulator and NDSs. Improvements can yield a more robust platform to systematically compare and interpret data across both approaches, ultimately leading to enhanced planning and safety regarding mobile phone use while driving.

First and second eye cataract surgery and driver self-regulation among older drivers with bilateral cataract: a prospective cohort study

BackgroundDriving a car is the most common form of transport among the older population. Common medical conditions such as cataract, increase with age and impact on the ability to drive. To compensate for visual decline, some cataract patients may self-regulate their driving while waiting for cataract surgery. However, little is known about the self-regulation practices of older drivers throughout the cataract surgery process. The aim of this study is to assess the impact of first and second eye cataract surgery on driver self-regulation practices, and to determine which objective measures of vision are associated with driver self-regulation.MethodsFifty-five older drivers with bilateral cataract aged 55+ years were assessed using the self-reported Driving Habits Questionnaire, the Mini-Mental State Examination and three objective visual measures in the month before cataract surgery, at least one to three months after first eye cataract surgery and at least one month after second eye cataract surgery. Participants’ natural driving behaviour in four driving situations was also examined for one week using an in-vehicle monitoring device. Two separate Generalised Estimating Equation logistic models were undertaken to assess the impact of first and second eye cataract surgery on driver-self-regulation status and which changes in visual measures were associated with driver self-regulation status.ResultsThe odds of being a self-regulator in at least one driving situation significantly decreased by 70% after first eye cataract surgery (OR: 0.3, 95% CI: 0.1–0.7) and by 90% after second eye surgery (OR: 0.1, 95% CI: 0.1–0.4), compared to before first eye surgery. Improvement in contrast sensitivity after cataract surgery was significantly associated with decreased odds of self-regulation (OR: 0.02, 95% CI: 0.01–0.4).ConclusionsThe findings provide a strong rationale for providing timely first and second eye cataract surgery for older drivers with bilateral cataract, in order to improve their mobility and independence.

Do older drivers with bilateral cataract self-regulate their driving while waiting for first eye cataract surgery?

ObjectivesTo analyze the association between visual impairment and driver self-regulation among a cohort of older drivers waiting for first eye cataract surgery.MethodsNinety-six drivers with bilateral cataract aged 55+ years were assessed before first eye cataract surgery. Data collection consisted of a researcher-administered questionnaire, objective visual measures (visual acuity, contrast sensitivity and stereopsis), a visual attention test (the useful field of view test) and a cognitive test (the Mini-Mental State Examination). Driver self-regulation practices were collected using the Driving Habits Questionnaire and were also measured with an in-vehicle monitoring device. Characteristics of self-regulators and non-self-regulators were compared and a logistic regression model was used to examine the association between 3 objective visual measures and driver self-regulation status.ResultsAfter controlling for potential confounding factors, only binocular contrast sensitivity (p=0.01), age (p=0.03) and gender (p=0.03) were significantly associated with driver self-regulation status. The odds of participants with better contrast sensitivity scores (better vision) self-regulating their driving in at least 1 driving situation decreased (odds ratio [OR]: 0.01, 95% CI: 0.00–0.28) while those of increasing age reported an increased odds of self-regulating their driving (OR: 1.08, 95% CI: 1.01–1.15). The odds of males self-regulating their driving was decreased compared with females (OR: 0.28, 95% CI: 0.09–0.86).ConclusionsWorse binocular contrast sensitivity scores, increasing age and being female were significantly associated with driver self-regulation. The study highlighted that while self-regulation was common among cataract patients, a proportion of those with poor vision did not self-regulate. Further research should determine how cataract patients could benefit from self-regulation strategies while waiting for cataract surgery.

Through the Looking Glass: A Review of the Literature Investigating the Impact of Glaucoma on Crash Risk, Driving Performance, and Driver Self-Regulation in Older Drivers.

Glaucoma can result in insidious degradation of the peripheral visual field. This can severely affect everyday life and impact fitness-to-drive. Despite the high prevalence of glaucoma in older adults and the increasing longevity of the overall population, the impact of glaucoma on driving performance, driving practices, and crash risk remains unclear and under examined. This review examines the literature that investigates glaucoma and crash risk, driving performance, cognitive demand, driving self-regulation, and driving cessation in older drivers. A search of the literature relating to driving performance, crash risk, driver self-regulation, and cognitive workload in drivers with glaucoma was conducted between September 2013 and December 2013. This review has identified that the literature related to glaucoma and driving performance, crash risk, cognitive demand, and driving practices in older adults is inconsistent. There is a particular lack of consensus about whether glaucoma is associated with an increased risk of a car crash, although further information available relating to driving performance and driver habits suggests that there is a negative impact of glaucoma. Specifically, when the driving performance of glaucoma patients with moderate to severe visual field loss is assessed using either on-road or off-road techniques, they are found to perform poorly. There is also some debate around the amount of insight glaucoma patients have into the effect of the disease on their driving ability. The research suggests that patients with glaucoma find driving situations (particularly driving at night) increasingly difficult. Furthermore, there appears to be a tendency for drivers with glaucoma to alter their driving habits or to voluntarily cease driving completely; however, this is not the case for all glaucoma patients and the finding may differ depending on the laterality of visual field loss. There is little literature available that investigates glaucoma and its relationship with driving. The few studies that have been conducted are varied in methodology and the results available are highly inconsistent. With an ageing population and heavy reliance on driving for personal mobility, further research into measuring the impact of glaucoma and driving is crucial to ensure a sustained quality of life for the elderly. The potential for future research is discussed.

The Cataract Extraction and Driving Ability Research Study Protocol: characterisation of deficits in driving performance and self-regulation among older drivers with bilateral cataract

PurposeCataract is one of the leading causes of visual impairment in Australia. As more older adults are driving, the number of people with cataract on the roads will increase. A...

What are the impacts of giving up the driving licence?

ABSTRACTDriving cessation is a gradual process, where driver's self-regulation plays an important role. Age-based licence renewal may interfere with this process and trigger premature driving cessation. The present study compares Danish drivers (aged 69 years at the baseline) who either renewed or gave up their driving licence. Data were collected in 2009 (N=1,792) and in 2012 (N=863). The standardised interviews covered respondents' background information, health and wellbeing, and transportation patterns. Non-renewers had poorer health already at baseline but did become more dependent on others in their activities after giving up their licence. In travel frequency, neither the differences between renewers and non-renewers nor the changes over time within the groups were pronounced. The groups differed in their use of transport modes already at the baseline: the renewers drove, while non-renewers travelled as passengers, used public transport, walked or cycled. Not renewing the licence was a strong predictor of unmet mobility needs, especially in relation to leisure activities. The present study indicates that younger seniors' mobility is not likely to be affected by the strict renewal policies. However, given the positive economic and safety consequences of independent mobility in old age, society should try to prevent unwarranted mobility loss. Having restrictive, ageist policies that moreover fail as societal investments may work against this goal.

Self-Regulation Minimizes Crash Risk from Attentional Effects of Cognitive Load during Auditory-Vocal Tasks

This study reanalyzes the data from a recent experimental report from the University of Utah investigating the effect on driving performance of auditory-vocal secondary tasks (such as cell phone and passenger conversations, speech-to-text, and a complex artificial cognitive task). The current objective is to estimate the relative risk of crashes associated with such auditory-vocal tasks. Contrary to the Utah study's assumption of an increase in crash risk from the attentional effects of cognitive load, a deeper analysis of the Utah data shows that driver self-regulation provides an effective countermeasure that offsets possible increases in crash risk. For example, drivers self-regulated their following distances to compensate for the slight increases in brake response time while performing auditory-vocal tasks. This new finding is supported by naturalistic driving data showing that cell phone conversation does not increase crash risk above that of normal baseline driving. The Utah data are next compared to those from a larger study that included visual-manual as well as auditory-vocal tasks. The Utah auditory-vocal tasks had negligible effects on response time compared to visual-manual tasks with socially acceptable crash risk, such as manual radio tuning. In conclusion, auditory-vocal tasks such as those in the Utah study are not expected to increase crash risk or impair real-world operation of an automobile, compared to normal baseline driving without performing such tasks. Language: en

Factors Affecting Drivers’ Cell Phone Use Behavior

The purpose of this study was to examine drivers’ cell phone use behavior as reflected in naturalistic driving data. Video data from 1 week's worth of driving for 108 participants were visually scored for all instances of cell phone use, including conversation and visual or manual (VM) tasks. The frequency of cell phone use for each participant was used to classify drivers’ behavior. Three frequency groups (low, moderate, and high) were scored across all drivers for conversation and VM tasks separately. The regression tree method was used to classify drivers’ cell phone use behavior and identify associated factors. Drivers’ individual factors, including age, annual driving mileage, and education levels, as well as situational factors, including use duration, time of day, road type, lighting (day and night), traffic conditions, and speed when initiating cell phone use, impacted drivers’ cell phone use behavior. The impacts of these factors were different for cell phone conversation and VM tasks. Traffic conditions were identified as affecting drivers’ cell phone VM task use frequency but not cell phone conversation frequency. The study also looked at driver self-regulation behavior based on the frequency of cell phone use.

Driver self-regulation and depressive symptoms in cataract patients awaiting surgery: a cross-sectional study

BackgroundCataract is an extremely common visual condition of ageing. Evidence suggests that visual impairment influences driving patterns and self-regulatory behavior among older drivers. However, little is known about the psychological effects of driver self-regulation among older drivers. Therefore, this study aimed to describe driver self-regulation practices among older bilateral cataract patients and to determine the association between self-regulation and depressive symptoms.MethodsNinety-nine older drivers with bilateral cataract were assessed the week before first eye cataract surgery. Driver self-regulation was measured via the Driving Habits Questionnaire. Depressive symptoms were assessed using the 20-item Center for Epidemiological Studies Depression Scale. Visual, demographic and cognitive data were also collected. Differences between self-regulators and non self-regulators were described and linear regression modeling used to determine the association between driver self-regulation and depressive symptoms score.ResultsAmong cataract patients, 48% reported self-regulating their driving to avoid at least one challenging situation. The situations most commonly avoided were driving at night (40%), on the freeway (12%), in the rain (9%) and parallel parking (8%). Self-regulators had significantly poorer contrast sensitivity in their worse eye than non self-regulators (p = 0.027). Driver self-regulation was significantly associated with increased depressive symptoms after controlling for potential confounding factors (p = 0.002).ConclusionsDriver self-regulation was associated with increased depressive symptoms among cataract patients. Further research should investigate this association among the general older population. Self-regulation programs aimed at older drivers may need to incorporate mental health elements to counteract unintended psychological effects.

Do Memory-Impaired Drivers and Their Family Members Agree on Driving Ability and Behaviors?

It is estimated that approximately one-third of people with dementia continue to drive. Compared with the general driving population, drivers with dementia are at an increased risk of unsafe motor vehicle operation. Self-screening is often the basis for self-regulation of driving. It is not known how well self-screening as a predominant strategy works for drivers with memory impairment. This descriptive study explored the perceptions of 22 dyads of drivers with memory impairment and their family members through 44 structured telephone interviews within 4 months after specialized driving assessment to gain insights into their level of agreement on the driver's health, functioning, and critical driving behaviors. Drivers and family members were in fair agreement about current driving patterns and driver self-regulation (such as avoiding driving at night, in bad weather, or in unfamiliar areas). However, when reports of functional ability (such as vision, strength, and flexibility) were compared, drivers rated their fitness more highly than those abilities were rated by their family members on most measures. Moreover, there was poor agreement between drivers and family members on reported occurrence of driving behaviors suggestive of impairment in critical driving skills. These results have implications for health care and other professionals engaged in determining driver fitness. The findings suggest limited value in self-screening or in family reports when assessing fitness to drive in persons with memory impairment. Professionals should exercise caution in relying on reports from family members or drivers, especially with respect to reported driving fitness and driving behaviors.

Is it feasible to screen older drivers using a battery of available tests and triage them into meaningful driving risk groups?

By 2030 the older population aged 60 and above is projected to be twice as large as any other age-group, growing from 35 million to 71.5 million and representing nearly...