Dual-task decrements in driving performance: The impact of task type,working memory,and the frequency of task performance

Driving while carrying out another (secondary) task interferes with performance, though the degree of interference may vary between tasks and individual drivers. In this study, we focused on two potentially interrelated individual difference variables that may play a role in determining dual-task interference: working memory capacity and the driver’s experience with the relevant secondary task. We used a driving simulator to measure interference, comparing single-task performance (driving alone) with driving performance during three secondary tasks: conversing on a handsfree cellphone, texting, and selecting a song on a touchscreen Mp3 player. Drivers also rated the difficulty of driving while carrying out each secondary task. For the individual difference variables, working memory was measured using the Operation Span test (OSPAN), and experience was assessed in terms of self-reported daily driving exposure and exposure to the relevant secondary tasks (frequency, duration). Overall, we found evidence of dual-task interference, though interference varied between tasks; the texting and Mp3 tasks produced significantly more interference than handsfree cellphone conversation. For the texting and Mp3 song selection tasks, interference was apparent in terms of increased steering variability, but for the Mp3 task there was also compensatory slowing, with drivers slowing down while carrying out the task. OSPAN performance and daily driving exposure were both covariates in predicting the amount of dual-task interference. However, our results suggest that in all but two cases, both involving the texting task, the effects of the OSPAN and the driving and secondary task exposure variables were independent rather than interrelated.     

Correlations of multiple rider behaviors with self-reported attitudes,perspectives on traffic rule strictness and social desirability

Powered Two-Wheeler (PTW) riders constitute a very vulnerable group of road users, while riding a PTW is considerably more dangerous than using any other motor vehicle. Behavioral issues have been identified major moderating factors to PTW crashes, as riders display great variability in their attitudes towards road safety. Τhe aim of this paper is to present a thorough, overarching structure of relationships correlating various unsafe stated PTW rider behaviors (riding after alcohol consumption, speeding, helmet use and texting) with several self-reported attitude parameters and factors regarding rider perspectives on traffic rule strictness and social desirability. A structural equation model (SEM) was developed using data from the ESRA2 survey, which provided a broad sample encompassing 5,958 respondent riders from 32 countries. Numerous statistical relationships were discovered and quantified correlating the four examined unsafe rider behaviors with eight latent unobserved variables. All covariances between unsafe behaviors were found to be positive and statistically significant, indicating that a rider who will engage more frequently in every single one of the four examined unsafe riding behaviors is more likely to also engage in all the others as well.     

Characteristics of college students who text while driving: Do their perceptions of a significant other influence their decisions?

IntroductionTexting while driving is a significant risk factor for automobile collisions. The use of cell phones is prevalent among young people and commonly reported when they drive.MethodA web-based survey of 861 college student drivers determined how texting was associated with other forms of risky driving, perceptions of risk, and their driving and texting interactions with a significant other.ResultsTexting drivers were more likely to engage in other risky driving behaviors, perceived less risk in texting and driving, felt more immune to traffic risks, and had friends who text and drive. Logistic regression analyses showed that even after adjusting for risky driving behaviors and perceived risk, texting drivers were significantly more likely to do so if they saw their significant other text and drive.ConclusionsTraffic safety campaigns need to address important social influences on this behavior.     

Analysis of vehicle-based lateral performance measures during distracted driving due to phone use

Distracted driving due to mobile phone use has been identified as a major contributor to accidents; therefore, it is required to develop ways for detecting driver distraction due to phone use. Though prior literature has documented various visual behavioural and physiological techniques to identify driver distraction, comparatively little is known about vehicle based performance features which can identify driver’s distracted state during phone conversation and texting while driving. Therefore, this study examined the effects of simple conversation, complex conversation, simple texting and complex texting tasks on vehicle based performance parameters such as standard deviation of lane positioning, number of lane excursions, mean and standard deviation of lateral acceleration, mean and standard deviation of steering wheel angle and steering reversal rates (for 1°, 5° and 10° angle differences). All these performance measures were collected for 100 licensed drivers, belonging to three age groups (young, mid-age and old age), with the help of a driving simulator. Effects of all the phone use conditions and driver demographics (age, gender and phone use habits) on the measures were analysed by repeated measures ANOVA tests. Results showed that 1°, 5° SRRs are able to identify all the distracted conditions except for simple conversation; while, 10° SSR can detect all the distracted conditions (including simple conversation). The results suggest that 10° SRR can be included in intelligent in-vehicle devices in order to detect distraction and alert drivers of their distracted state. This can prevent mobile phone use during driving and therefore can help in reducing the road accidents due to mobile phone distractions.     

Predicting intentions to text and call while driving using the theory of planned behaviour

There is extensive evidence that using a mobile phone while driving causes degradation in driving performance, and thereby results in reduced safety on the road. The present study examined intentions to use mobile phones while driving using the Theory of Planned Behaviour (TPB). A total of 212 Ukrainian drivers (mean age = 35 years SD = 10 years; males = 82%) completed a survey that included measures of the TPB components related to intentions to send or read text messages or to make or receive handheld phone calls across two different scenarios; one where they were running late, and the other when they were not in a hurry. Measures of the frequency of mobile phone use were also collected. The results showed that 63% of the sample reported using a mobile phone while driving at least daily, with the most frequent types of usage being making and answering a phone call with a handheld device. The most consistent predictor of intentions to interact with a mobile phone while driving was having a positive attitude towards doing so. Perceived behavioural control was also significantly and positively associated with mobile phone use while driving, but only a small number of associations were found with subjective norms. Our results suggest that intentions to interact with mobile phones while driving may be context specific.     

Even experienced phone users drive worse while texting – A driving simulator study

Several studies have clearly shown that texting on a mobile phone increases crash risk (e.g. Dingus et al., 2006; Victor et al., 2014). However, the frequency of texting while driving still remains high (e.g. Vollrath, Huemer, Teller & Likhacheva, 2016). One reason may be that drivers are convinced that they are able to manage this dual task due to their competency in driving and texting. From a theoretical point of view, this may be true within limits – two well-learned, automatically processed tasks may require so few resources most of the time that interferences may not occur.In order to test this assumption, a study with a standardized driving simulator task (the lane change task, LCT; Mattes, 2003) was done with n = 40 drivers selected for their driving experience and tested for their texting abilities. The effect of driving experience (high vs. low) and texting competence (high vs. low) on driving performance was examined in single (driving only) and dual-task (driving and texting) conditions. Additionally, a subjective assessment of one’s task performance was obtained. Texting on the mobile phone significantly impaired driving performance. While driving experience did not have an influence, the deteriorating effect of texting was significantly less pronounced in highly competent phone users. Interestingly, this objective effect was not found in the subjective assessment. Drivers with a high texting competence felt as impaired as drivers with a low texting competence. This is in line with the finding that even in this simple driving task their performance was still significantly deteriorated as compared to driving, only. Thus, it seems that the reason why people text while driving is not that they are not aware of the performance loss. However, this awareness of the possible risk does not seem sufficient to prevent them from texting while driving.     

Does texting interrupt imitation learning in 19-month-old infants?

Observed disruptions to parent-child interactions during parental media use, such as texting, have been termed technoference. For example, when a language learning interaction was disrupted by a phone call, toddlers were less likely to acquire the word. Other studies demonstrated that parents often exhibit a still face while silently reading information on their cell phones. In the present study, the effect of a text interruption on infant imitation learning was examined. Parents demonstrated three target actions to their infants and then infants were given the opportunity to repeat those interactions. The actions were demonstrated four times. Text interruptions occurred before or between demonstrations. Performance of these groups was compared to a baseline control group where the infant did not see a demonstration of the target actions and a no-interruption group where the parents demonstrated the target actions four times without interruption. Parents were randomly assigned to three conditions, interruption-first condition, one-interruption condition, or three-interruptions condition. Infant behavior was measured during the interruptions. Across text interruption groups parents exhibited high levels of still face during the interruptions (77 %). However, infants in all 3 interruption groups performed significantly above the baseline control indicating learning despite the interruptions. Higher reported maternal reliance on the smartphone was related to poorer imitation performance overall. In contrast, when parents reported that they found it easier to multi-task infant imitation rates were higher. These findings indicate that infants can learn under conditions of brief technoference and that individual differences in family media ecology are associated with learning.     

The factors underlying the decision to text while driving

Using the Theory of Planned Behaviour (TPB), this study looked at the motivations and reasons behind the behaviour of texting while driving. Following an elicitation study, 150 participants completed a questionnaire measuring self-efficacy and moral norms in addition to traditional TPB variables. Texting while driving was found to be a common behaviour although prevalence varied between age groups. While the youngest age group were more likely to have ever sent a text message while driving, those aged 35–44 years old were most likely to have read a message while driving and to intend to text while driving in the future. Moral norms had the strongest significant correlation with intentions to text while driving. Similar to past research the traditional TPB variables explained significant variance in intentions to perform the behaviour. To be fully effective, future campaigns and interventions to reduce the behaviour are advised to focus on the moral aspect of the behaviour and the beliefs that it saves time and prevents boredom. The setting of campaigns or interventions and the mode of delivery should also be considered. Efforts to deter the behaviour should be aimed at those of all ages and not just younger drivers.     

The role of legal and moral norms to regulate the behavior of texting while driving

Despite a nationwide lawful effort to regulate texting-while-driving behavior, little change has been reported. This study assessed the effect of current legal enforcement on attitudinal and behavioral responses toward texting while driving in conjunction with potential influences of two types of perceived norms—legal and moral. An online survey was conducted with 313 college students recruited from three states where the history of a banning law of texting while driving varied (more than 3 years, less than 1 year, and none). The students self-reported perceived legal norm, perceived moral norm, perceived risk of texting while driving, frequency of texting while driving, attitude toward texting while driving, and intention of texting while driving. General linear model analyses revealed that the mere presence of legal enforcement showed a negative relationship with frequency of behavior only for the state with the banning law in effect more than 3 years. While the perceived legal norm showed inconsistent relationships with outcome variables, the perceived moral norm appeared most promising to discourage texting while driving among young drivers. A banning law for texting-while-driving behavior not only backfired on the actual behavior in a short-term effect, but also required a long-term exposure of the law to change the actual behavior among college students. On the other hand, cultivation of a moral norm to regulate the behavior of texting while driving is particularly encouraged in that the stable nature of this psychological variable can play a role to suppress possible reactance evoked by an external force. Policy makers are encouraged to harness their approach to regulate young drivers’ texting while driving with the strategy that appeals to the drivers’ moral beliefs rather than simply forcing them to comply with the law.     

The effectiveness of “Soft-blocking” for reducing clicking on-screen while driving

Smartphone usage while driving is recognized as a compromise on road safety. We investigated if silencing and hiding of notifications from drivers (soft blocking) can reduce clicks on the screen while driving and if the effect of the soft blocking would be different for different speed thresholds (STs) (i.e., at driving speed greater than 0 km/h, greater than 1 km/h….and greater than 90 km/h). Drivers installed a smartphone application, which continuously monitored their phones. In the intervention group (N = 22), the application switched to the soft blocking mode during the study's intervention period, while in the control group (N = 29) it remained in a recording-only mode. We ran a Poisson regression model on the click events frequency (CEF) to estimate the soft blocking effect for each of the STs between 0 and 90 km/h. Our analyses indicated that the soft blocking effectiveness was indeed speed-dependent and pointed to a decline in CEF from ST > 55 km/h and to mixed results if ST < 55 km/h. We identify a potential of soft blocking to reduce phone usage while driving and recommend ST-dependent soft blocking. We also recommend using different STs in future investigations on the effectiveness of soft blocking.