A study of self-reported personal cannabis use and state legal status and associations with engagement in and perceptions of cannabis-impaired driving.

Objective: The objectives of the current study were to (1) characterize predictors of perceived risk of driving within 2 h of cannabis use and driving after cannabis use in a sample of adults who have used cannabis in the past year and (2) determine whether the influence of these predictors vary by state legalizations status.Methods: Data for this study were from online surveys. Study participants from Colorado, Iowa, and Illinois were included if they reported being between 25 and 40 years old and had a history of cannabis use. Outcome variables included (1) days of cannabis use per month, (2) reported driving within 2 h of cannabis use (vs. not driving within 2 h as reference), (3) proportion of driving after cannabis use days per month (days of driving a car within 2 h of cannabis use per month/days of cannabis use per month), and (4) perception of safety of driving after cannabis use. Potential predictors included age of first use of cannabis, gender, education status, and state of residence. The SAS GLMSELECT Procedure was used for the analysis.Results: Increased age of first use of cannabis was associated with decreased days of cannabis use per month (B = -0.51 days/month per year), a reduction in the proportion of driving after cannabis use days per month (B = -0.02 per month), and decreased perception of safety of driving after cannabis use (B = -0.06 per year). Female gender was also associated with less use (B = -2.3 days per month), a lower proportion of driving following use (B = -0.06 days driving/days used), and decreased perception of safety (B = -0.29). In addition, residents of Colorado reported using the most days, had the highest likelihood of driving within 2 h of use, and had the most positive perceptions of being able to safely drive after cannabis use.Conclusions: The delay in onset of cannabis use may mitigate its use among adults and driving after cannabis use. This has important implications for driver safety. Intervention programs for reducing cannabis's effects on driving should focus on individuals with early onset of use, male drivers, and drivers in states where cannabis for adult recreational use is legalized.

Coupling neuroscience and driving simulation: A systematic review of studies on crash-risk behaviors in young drivers.

OBJECTIVE: Motor vehicle crashes are a leading cause of death for adolescents and young adults. The aim of this study is to examine and discuss the state-of-the-art literature which uses neuroscience methods in the context of driving simulation to study adolescent and young adult drivers. METHODS: We conducted a systematic English-language literature search of Ovid MEDLINE (1946-2020), PsycINFO (1967-2020), PubMed, Web of Science, SCOPUS, and CINAHL using keywords and MeSH terms. Studies were excluded if participants were not within the ages of 15-25, if the driving simulator did not include a visual monitor/computer monitor/projection screen and steering wheel and foot pedals, or brain data (specifically EEG [electroencephalogram], fNIRS [functional near-infrared spectroscopy], or fMRI [functional magnetic resonance imaging]) was not collected at the same time as driving simulation data. RESULTS: Seventy-six full text articles of the 736 studies that met inclusion criteria were included in the final review. The 76 articles used one of the following neuroscience methods: electrophysiology, functional near-infrared spectroscopy, or functional magnetic resonance imaging. In the identified studies, there were primarily two areas of investigation pursued; driving impairment and distraction in driving. Impairment studies primarily explored the areas of drowsy/fatigued driving or alcohol-impaired driving. Studies of distracted driving primarily focused on cognitive load and auditory and visual distractors. CONCLUSIONS: Our state of the science systematic review highlights the feasibility for coupling neuroscience with driving simulation to study the neurocorrelates of driving behaviors in the context of young drivers and neuromaturation. Findings show that, to date, most research has focused on examining brain correlates and driving behaviors related to contributing factors for fatal motor vehicle crashes. However, there remains a considerable paucity of research designed to understand underlying brain mechanisms that might otherwise facilitate greater understanding of individual variability of normative and risky driving behavior within the young driving population.

Brain-based limitations in attention and secondary task engagement during high-fidelity driving simulation among young adults.

Distracted driving remains a leading factor in fatal motor vehicle crashes, particularly in young drivers. Due to ongoing neuromaturation, attention capabilities are changing and improving throughout young adulthood. Here, we sought to bridge neuroscience with driving simulation by evaluating the effects of driving on attention processing through a selective auditory attention task. Participants (18-25 years old) engaged in an auditory attention task during LOAD (driving a high-fidelity simulator) and No-LOAD conditions (sitting in the parked simulator). For the auditory task, participants responded to a target auditory tone in a target ear. The event-related potential components, collected from frontal and posterior regions, P2 and P3, were used to evaluate attention processing across LOAD and No-LOAD conditions for attended and unattended stimuli. Data from 24 participants were evaluated in repeated measures ANOVAs, considering interactions between load and attention conditions for the P2 and P3 components of the cortical region. We observed a significant difference between response to attended and unattended stimuli for posterior P2 and P3 responses at the frontal and posterior midline sites. Comparing LOAD and No-LOAD conditions, there was a significant difference for P2 response at the posterior site and P3 response at the frontal site. A significant interaction between load and attended stimuli was found for P3 response at the posterior site. These data document differences in neural processing of auditory stimuli during high-fidelity simulated driving versus sitting parked in the simulator. Findings suggest the cognitive load of driving affects auditory attention.