Influence of cannabis use history on the impact of acute cannabis smoking on simulated driving performance during a distraction task.

Objective: This research explores the driving performance of people who use cannabis daily or occasionally during distraction tasks performed following acute cannabis use.Methods: Healthy adults aged 25 to 45 years with different cannabis usage histories were recruited to participate in a within-subjects controlled experiment using a car-based driving simulator. Participants were classified as having daily use (n = 31), occasional use (1 or 2 times per week; n = 24), or no-use (n = 30). Participants completed a practice drive followed by four 5-10 minute driving scenarios during the baseline period. Participants then smoked self-procured cannabis flower ad libitum for up to 15 minutes. Thirty minutes later, they completed four additional 5-10 minute scenarios. Scenarios were paired according to difficulty and randomized across the baseline and post-use periods. Each scenario contained between 0 and 3 repetitions of a distraction task where the participant was prompted by an audio message to select an app from a 4 × 5 grid displayed on a mounted tablet, a step that would require briefly looking away from the roadway. Measures of driving performance (lane departures, standard deviation of lateral position) were assessed during the five-second period following the audio trigger and analyzed using generalized linear mixed models.Results: Those with a pattern of occasional use were significantly more likely to experience a lane departure during distraction periods after acute cannabis use relative to baseline (OR = 3.71, p = 0.04, CI = 1.04, 13.17), while those with daily use did not exhibit a similar increase (OR = 1.56, p = 0.43, CI = 0.52, 4.64). Changes in departure risk were significantly greater for the occasional use group compared to no-use (p = 0.02), but not for the daily use group compared to no-use (p = 0.18). However, following acute use, those who use daily exhibited decreases in speed relative to baseline in comparison to the changes observed in the no-use group (p = 0.02), while differences between occasional and no-use did not reach statistical significance (p = 0.052). Differences in standard deviation of lateral position were not statistically significant, likely due to the short duration of tasks.Conclusions: These results find the largest potential safety concerns associated with a pattern of occasional use, who displayed an increase in lane departures after acute cannabis smoking. Those in the daily use group decreased their speed, which may be interpreted as compensation for drug effects. Further research is needed to understand the effects during longer and more complex secondary tasks.

Narrative persuasion and stigma: Using news accounts to denormalize texting while driving.

Despite nearly universal texting while driving bans in U.S. states, distracted driving still poses a major risk for American motorists and pedestrians on a daily basis. We argue texting while driving behavior, due to its cultural, social, and psychological motivations, may be addressed by cultivating a stigma to denormalize TWD much in the same way public health campaigns and bans did with tobacco use. While extant strategies may similarly stigmatize this risky behavior, we contend the stigmatizing effect of news narratives offers an untapped and unexamined resource. In this paper we draw on emergent findings in narrative persuasion work to present an exploratory analysis and evidence indicates news narratives, through narrative engagement, can both stigmatize TWD behavior and diminish attitudes toward distracted driving. These initial findings are then validated against an independent sample. If applied widely, this method may be applied to increase social pressure against distracted driving, leading to fewer people engaging in TWD behavior, and making roads safer.

Relationships Between Older Drivers' Cognitive Abilities as Assessed on the MoCA and Glance Patterns During Visual-Manual Radio Tuning While Driving.

Objective: Research has established that long off-road glances increase crash risk, and other work has shown increased off-road glance behavior in older drivers. This study investigated the relationship between older drivers' (M = 66.3, range 61-69 years) cognitive abilities and the duration of off-road glances while engaged in secondary visual-manual activities. Method: Twenty-two drivers completed the Montreal Cognitive Assessment (MoCA) prior to driving an instrumented vehicle and completing a set of radio-tuning tasks. Glance behavior was recorded and manually coded into 7 glance regions (toward the forward roadway, instrument cluster, center stack, rearview mirror, left, right, and other). Results: On average, older drivers with higher MoCA scores used shorter glances and glanced away from the forward roadway for less total time when manually tuning the radio. Discussion: These findings suggest that lower MoCA scores may represent a driving force behind the "age" differences reported in earlier studies of off-road glance behavior. Questions are raised concerning the identification of MoCA scores that might be used as inclusion cut-points in driving research and in identifying individuals needing further evaluation related to suitability for continuance of driving.