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Distracting tasks have persisting effects on young and older drivers’ braking performance
Abstract
It is well established that car driving performance suffers when the driver concurrently engages in a distracting activity, such as talking on a cell phone. The present study investigates whether the effects of driver distraction are short-lived, or rather persist for some time. Age-related differences are evaluated as well. Sixty-three young and 61 older adults were tested in a driving simulator. They were asked to follow a lead car that drove at a constant speed, and to concurrently engage in a pseudorandom sequence of distracting tasks (typing, reasoning, memorizing). When the lead car braked, participants had to brake as well to prevent a collision. The stimulus onset asynchrony between the braking task and the last preceding distraction was 11.49 ± 1.99 s. Each person was tested once in a multitasking condition (as described above), and once in a control condition without distracting tasks. Outcome measures quantified distance keeping and lane keeping while participants braked to the lead car. We found that braking responses differed significantly between conditions; this difference could be interpreted as a combination of performance deficits and compensatory strategies in the multitasking condition compared to the control condition. We also found significant differences between age groups, which could be interpreted similarly. Differences between age groups were less pronounced in the multitasking than in the control condition. All observed effects were associated with participants’ executive functioning. Our findings confirm that distractions have an impact on braking responses, and they document for the first time that this impact can persist for about 11.5 s. We attribute this persistence to a task set effect, and discuss the practical relevance of our findings.
... In contrast to the above work, a recent study on simulated car driving documented that the in uence of additional tasks on drivers' subsequent braking responses can persist even if SOA is dramatically longer than 400 ms (Bock et al., 2021b). That study administered the braking tasks with an SOA of about 11.5 s after additional tasks; in spite of this very long SOA, the driver's control of the car during the braking maneuver was poorer than in a control condition without additional tasks. ...
... The earlier mentioned driving studies followed the tradition of PRP research and evaluated the reaction time of braking responses. In contrast, Bock et al. (2021b) followed the tradition of accident prevention research and evaluated the lateral lane position and intervehicle distance of the driver's car, i.e., variables that are more directly related to tra c safety (Chaparro et al., 2005;Drews et al., 2009;Hancock et al., 2003). One could argue that the reaction time of braking responses re ects simple, automated actions issued to prevent an imminent danger, while lane and distance keeping involves more complex cognitive processing: drivers must continuously monitor a widespread visual environment with stationary and moving objects, and must adjust the steering wheel, the gas pedal and the brake pedal accordingly. ...
... The present work was carried out to distinguish between the above explanations. As in Bock et al. (2021b), we compared braking responses in a multitasking condition where multiple additional tasks were administered at SOA ≈ 11.5 s, with those in a control condition where no additional tasks were administered. As in the earlier driving studies, however, we evaluate the reaction time of braking responses rather than lane and distance keeping. ...
It well established that the presentation of one task increases the reaction time on a subsequent task, if the stimulus onset asynchrony (SOA) between tasks is less than about 400 ms. This psychological refractory period (PRP) effect has been observed both in classical laboratory paradigms and in simulated car driving. Here we report about an effect that persists substantially longer than the PRP effect. In a driving simulator, 120 healthy older participants followed a lead car that mostly drove at a constant speed, and they had to brake when the lead car braked. Concurrently, they engaged in several additional tasks. SOA between the braking task and the last preceding additional task was about 11.5 s. In a control condition, the braking task was administered without additional tasks. We found that the reaction time of braking responses averaged 0.77 s without additional tasks, but averaged 1.45 s with additional tasks. This increase was less pronounced at smaller inter-vehicle distances, and was not compensated by faster foot movements from the gas pedal to the brake pedal. We conclude that detrimental effects of additional tasks on subsequent braking responses can be much more persistent than the PRP effect, possibly because of the need to maintain multiple task sets. We further conclude that the detrimental effects can be ameliorated at small inter-vehicle distances, possibly by mobilizing extra cognitive resources when response urgency is high. As a practical implication of our study, distracting stimuli can have persisting detrimental effects on traffic safety.
... A recent study collated the reasons for road traffic accidents suggested that driver distraction is responsible for 10-50% of car crashes. 3 The common reasons for driver distractions includes the advertisement boards on the roads, co-passenger interaction, talking over phone while driving, tracking addresses and operating the audio systems in the vehi-cle. [3][4][5][6] Car divers who have an increased reaction time are more susceptible to automobile accidents 7 and therefore reaction time is regarded as an important aspect in designing prevention strategies. ...
... 3 The common reasons for driver distractions includes the advertisement boards on the roads, co-passenger interaction, talking over phone while driving, tracking addresses and operating the audio systems in the vehi-cle. [3][4][5][6] Car divers who have an increased reaction time are more susceptible to automobile accidents 7 and therefore reaction time is regarded as an important aspect in designing prevention strategies. 8 Surprisingly, there are no much interventional studies conducted in this domain which can help in reducing the number of accidents and associated woes. ...
Problem considered
Road accidents are a growing concern in developing countries that needs immediate attention. The present study evaluated the role of Maha Mrityunjaya mantra (MMM), a vedic practice in reducing reaction time, burnout and improving sleep among commercial drivers.
Methods
Fifty commercial drivers (Age 39.92 ± 8.64) were enrolled for a 2 months MMM chanting session (21 rounds, 15 min daily, 5 sessions/week). The effects were measured at the baseline and at the end of 2 months using ruler drop test (RDT), Pittsburgh Sleep Quality Index (PSQI) and Oldenburg burnout inventory (OLBI).
Results
The average work experience and duration of working hours per day were 15.1 ± 7.75 years and for 8.7 ± 1.7 h respectively. We observed significant changes in PSQI scores (Pre- 7.44 ± 3.9, Post- 4.82 ± 2.32; p < 0.01), OLBQI (Pre-38.24 ± 3.22, Post-34.24 ± 2.64; p < 0.01, effect size 1.000) and RDT scores (Pre-16 ± 3.9, Post-10.28 ± 2.79; p < 0.01). Spearman's correlation revealed a weak positive association between improvement in sleep with reaction time (rs = 0.247) and burnout scores (rs = 0.097).
Conclusion
The present study concludes MMM chanting may be beneficial in improving the reaction time among drivers, which may be useful as a strategy in preventing road traffic accidents. However, robust randomized control trials are warranted before making generalized recommendations.
... The selected studies included a sample of 3033 participants (n =1984 male; n = 1049 female) who participated in simulated driving experiments. The minimum number was 14 [49], and the maximum was 134 [50] participants per study. The gender distribution was not mentioned in two of the extracted studies. ...
Road safety is increasingly threatened by distracted driving. Studies have shown that there is a significantly increased risk for a driver of being involved in a car crash due to visual distractions (not watching the road), manual distractions (hands are off the wheel for other non-driving activities), and cognitive and acoustic distractions (the driver is not focused on the driving task). Driving simulators (DSs) are powerful tools for identifying drivers’ responses to different distracting factors in a safe manner. This paper aims to systematically review simulator-based studies to investigate what types of distractions are introduced when using the phone for texting while driving (TWD), what hardware and measures are used to analyze distraction, and what the impact of using mobile devices to read and write messages while driving is on driving performance. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews (PRISMA-ScR) guidelines. A total of 7151 studies were identified in the database search, of which 67 were included in the review, and they were analyzed in order to respond to four research questions. The main findings revealed that TWD distraction has negative effects on driving performance, affecting drivers’ divided attention and concentration, which can lead to potentially life-threatening traffic events. We also provide several recommendations for driving simulators that can ensure high reliability and validity for experiments. This review can serve as a basis for regulators and interested parties to propose restrictions related to using mobile phones in a vehicle and improve road safety.
... In line with the current literature, our findings showed a detrimental effect of advancing age on driving performance [32,34,91,92]. Research on driving performance demonstrated that advancing age is associated with slower driving speed [18,31,93]. ...
Research on multitasking driving has suggested age-related deterioration in driving performance. It has been shown that physical and cognitive functioning, which are related to driving performance and decline with aging, are positively associated with physical activity behavior. This study aimed to explore whether driving performance decline becomes severe with advancing age and whether physical activity behavior modifies age-related deterioration in driving performance. A total of one hundred forty-one healthy adults were categorized into three groups based on their age; old-old (74.21 ± 2.33 years), young-old (66.53 ± 1.50 years), and young adults (23.25 ± 2.82 years). Participants completed a realistic multitasking driving task. Physical activity and cardiorespiratory fitness levels were evaluated. Older groups drove more slowly and laterally than young adults, and old-old adults drove slower than young-old ones across the whole driving course. Physical activity level did not interact with the aging effect on driving performance, whereas cardiovascular fitness interacted. Higher-fitness young-old and young adults drove faster than higher-fitness old-old adults. Higher-fitness old adults drove more laterally than higher-fitness young adults. The present study demonstrated a gradual decline in driving performance in old adults, and cardiorespiratory fitness interacted with the aging effect on driving performance. Future research on the interaction of aging and physical activity behavior on driving performance in different age groups is of great value and may help deepen our knowledge.
... Still, the most widely accepted definition is a "diversion of attention away from activities critical for safe driving towards a competing activity, which may result in insufficient or no attention to activities critical for safe driving" [2]. It can deteriorate driving performance visually (not looking at the road), cognitively (not paying attention to the road), and physically (hands off the steering wheel) [3,4]. Distracted driving occurs when the primary task (driving) is shared with a non-driving related secondary task. ...
The number of traffic accidents because of distracted driving is increasing rapidly worldwide. Hence, the main objective of the present study is to review the effects of different distracting factors on driving performance indicators. Distracting factors considered in this study are roadside advertisements (billboards), mobile use, in-built vehicle systems, and sleepiness; and driving performance indicators are lane deviation, reaction time, and speed variation. Studies from existing literature reveal that all the distracting factors distract drivers from forwarding roadways in many ways. The location and content displayed on the billboard and the use of mobile phones increase reaction time. However, the former decreases the driver’s ability to control the vehicle, and the latter increases the speed variation and reduces lane-keeping capacity. Lateral vehicle control and reaction time are compromised when drivers engage in searching for songs or videos on music players. When sleepiness occurs, drivers exhibit a higher standard deviation of speed and a decreased headway distance. Nevertheless, most of the studies in this area are carried out in developed countries like the USA and European countries. Therefore, a detailed study and further research in developing countries like India, where activities like installing billboards and mobile phone use are increasing day by day due to the rapid urbanization of major cities in the country, are quite essential. Doi: 10.28991/CEJ-2022-08-02-014 Full Text: PDF
Purpose of the research
Driving is a complex task that requires appropriate engagement in, and regulation of, sustained attention and divided attention. This study explored the sustained- and divided-attention function of novice young adult drivers and experienced adult drivers.
Methods
Fifteen novice young adult drivers (mean age = 20.07) and 18 experienced adult drivers (mean age = 41.33) participated in the study. The participants’ sustained and divided attention were assessed using a computerised fixed Sustained Attention-to-Response Task (SART) and a modified version with low cognitive-load and high cognitive-load conditions. Their attention was also assessed using the Color Trails Test (CTT) and Digit Span Test (DST). The participants’ cognitive resources that were available during the assessments were monitored using the Rating Scale Mental Effort (RSME).
Results
The main results of this study showed that the experienced drivers had significantly higher performance in terms of accuracy in both sustained attention (p = 0.011) and divided attention (p = 0.008 and 0.006 in low and high cognitive-load conditions, respectively) components of the SART. No significant differences in the CTT and DST were found between the two groups. The results of the RSME also indicated that both groups had comparable cognitive resources available throughout the assessments.
Conclusions
This study suggests that experienced adult drivers have a higher developed ability to engage in and maintain sustained and divided attention appropriately. These results provide insight related to attention function, which might affect novice young adult drivers compared with experienced drivers.
Driving is a complex cognitive-motor task that requires the continuous integration of multisensory information, cognitive processes, and motor actions. With higher age, driving becomes increasingly challenging as a result of naturally declining neurophysiological resources. Performing additional subtasks, such as conversations with passengers or interactions with in-vehicle devices (e.g., adjusting the radio), may further challenge neurocognitive resources that are required to maintain driving performance. Based on declining brain physiological resources and inferior neurocognitive functioning, older adults (OA) may show higher brain activation and larger performance decrements than younger adults (YA) when engaging in additional subtasks during driving. Age differences, however, may further vary for different neurocognitive task demands, such that driving performance of OA might be particularly affected by certain subtasks. In this study, we hence investigated the brain functional correlates of age differences in driving behavior during concurrent subtask performance in YA and OA. Our final sample consisted of thirty younger (21.80 ± 1.73y, 15 female) and thirty older (69.43 ± 3.30y, 12 female) regular drivers that drove along a typical rural road (25 - 30 min) in a driving simulator and performed three different concurrent subtasks that were presented auditorily or visually: typing a 3-digit number (TYPE), comparing traffic news and gas station prices (working memory, WM), and stating arguments (ARG). We measured variability in lateral car position, velocity, and following distance to a frontal lead car as the standard deviation from 0 to 15 s after subtask onset. Brain activity was continuously recorded using functional near-infrared spectroscopy over the dorsolateral prefrontal cortex. Both YA and OA particularly varied in their lateral position during TYPE with a more pronounced effect in OA. For YA, in contrast, ARG led to higher variability in velocity compared to TYPE and WM, whereas OA showed no task-specific differences. Substantiating our behavioral findings, OA revealed the largest brain functional response to TYPE, while YA demonstrated a very distinct activation during ARG and smaller hemodynamic responses to TYPE and WM. Brain activity in the DLPFC was, overall, not significantly, but small to moderately related to certain behavioral performance parameters (mainly lateral position). We conclude that both OA and YA are vulnerable to distractive subtasks while driving. Age differences, however, seem to largely depend on neurocognitive task demands. OA may be at higher risk for accidents when performing visuo-motor subtasks (e.g., interacting with navigational systems) during driving while YA may be more (cognitively) distracted when talking to passengers.
Presentation of a task T1 typically delays the response to a subsequent task T2, more so with high temporal task overlap than with low temporal overlap. This so-called “psychological refractory period effect” (PRP effect) has been observed even if T1 required not a choice between distinct stimulus–response pairs, but rather between a given stimulus–response pair occurring once or twice. We explored which response strategy participants use for responding to such an unusual type of T1 and how such a T1 interacts with T2 performance. In a driving simulator, participants followed a lead car and had to honk when that car’s rear window changed color (T1). In condition “pure”, the color always changed once and required a single honk; in condition “mixed”, the color changed once and required a single honk on some trials, but on other trials, it changed twice 200 ms apart and required a double honk. Participants also had to brake when the lead car braked (T2). On dual-task trials, T1 preceded T2 with a varying stimulus onset asynchrony (SOA) of 50–1200 ms. Reaction time to the first T1 stimulus was similar in “pure” and “mixed” and it was comparable with the reaction time to the second T1 stimulus. Reaction time to the T2 stimulus increased as SOA decreased from 350 to 50 ms, confirming the existence of a PRP effect. Furthermore, reaction time to the T2 stimulus was similar in “pure” and in “mixed” with one T1 stimulus, but was higher in “mixed” with two T1 stimuli. This pattern of findings is compatible with the view that presentation of the first T1 stimulus triggers a single response, which is amended into a double response, if a second T1 stimulus is displayed. The amendment does not need to wait until central processing of the original response is completed, and it therefore begins with no delay beyond the regular reaction time. Our findings further suggest that the mere possibility of a second T1 stimulus being presented does not increase the PRP effect on T2, probably because response amendments are not equivalent to classical response choices. However, the actual presentation of a second T1 stimulus indeed does increase the PRP effect on T2, probably because amendments start 200 ms later than the original response, and therefore prolong central processing of T1.
Introduction
Using factor analysis, several studies reported that higher-order cognitive control involves separable executive functions. However, the number and definition of the purported functions differed between studies. One possible explanation for this discrepancy is that executive functions don’t exhibit a clear factorial structure, i.e., there is no clear dichotomy between executive function tests which are well-correlated (representing a common factor) and those which are poorly correlated (representing distinct factors). We scrutinize this explanation separately in data from young and from older persons.
Methods & results
Young and older volunteers completed cognitive tests of the purported executive functions shifting, updating, inhibition and dual-tasking (two tests per function). Confirmatory and exploratory factor analyses yielded, for either age group, factorial structures that were within the range reported in literature. More importantly, when correlations between tests were sorted in ascending order, and were then fitted them by piecewise linear regression with a breakpoint, there was no evidence for a distinct breakpoint between low and high correlations in either age group. Correlations between tests were significantly higher in older compared to young participants, and the pattern of test pairs with high and with low correlations differed between age groups.
Discussion
The absence of a breakpoint indicates that executive function tests don’t segregate into well-correlated and poorly correlated pairs, and therefore are not well suited for factor analyses. We suggest that executive functions are better described as a partly overlapping rather than a factorial structure. The increase of correlations in older participants supports the existence of age-related dedifferentiation, and the dissimilarity of correlations in the two age groups supports the existence of age-related reorganization.
Using data from the Australian Naturalistic Driving Study (ANDS), this study examined patterns of secondary task engagement (e.g., mobile phone use, manipulating centre stack controls) during everyday driving trips to determine the type and duration of secondary task engaged in. Safety-related incidents associated with secondary task engagement were also examined. Results revealed that driver engagement in secondary tasks was frequent, with drivers engaging in one or more secondary tasks every 96 seconds, on average. However, drivers were more likely to initiate engagement in secondary tasks when the vehicle was stationary, suggesting that drivers do self-regulate the timing of task engagement to a certain degree. There was also evidence that drivers modified their engagement in a way suggestive of limiting their exposure to risk by engaging in some secondary tasks for shorter periods when the vehicle was moving compared to when it was stationary. Despite this, almost six percent of secondary tasks events were associated with a safety-related incident. The findings will be useful in targeting distraction countermeasures and policies and determining the effectiveness of these in managing driver distraction.
Driving safety depends on the drivers’ attentional focus on the driving task. Especially in complex situations, distraction due to secondary stimuli can impair driving performance. The inhibition of distractors or inadequate prepotent responses to irrelevant stimuli requires cognitive control, which is assumed to be reduced with increasing age. The present EEG study investigated the effects of secondary acoustic and visual stimuli on driving performance of younger and older car drivers in a driving simulator task. The participants had to respond to brake lights of a preceding car under different distraction conditions and with varying task difficulties. Overall, the anticipation of high demanding tasks affected braking response behavior in young and especially in older adults, who showed reduced cognitive control to task-relevant braking stimuli, as reflected by a smaller P3b. In a more easy (perception only) task, simultaneously presented acoustic stimuli accelerated braking response times (RTs) in young and older adults, which was associated with a pronounced P2. In contrast, secondary visual stimuli increased braking RTs in older adults, associated with a reduced P3b. In a more difficult (discrimination) task, braking response behavior was impaired by the presence of secondary acoustic and visual stimuli in young and older drivers. Braking RT increased (and the P3b decreased), especially when the responses to the secondary stimuli had to be suppressed. This negative effect was more pronounced with visual secondary stimuli, and especially so in the older group. In sum, the results suggest an impaired resistance to distractor interference and a reduced inhibition of prepotent responses in older drivers. This was most pronounced when the processing of task-relevant and irrelevant stimuli engage the same mental resources, for example, by sharing the same stimulus modality.
Human multitasking is typically studied by repeatedly presenting two tasks, either sequentially (task switch paradigms) or overlapping in time (dual-task paradigms). This is different from everyday life, which typically presents an ever-changing sequence of many different tasks. Realistic multitasking therefore requires an ongoing orchestration of task switching and dual-tasking. Here we investigate whether the age-related decay of multitasking, which has been documented with pure task-switch and pure dual-task paradigms, can also be quantified with a more realistic car driving paradigm. 63 young (20–30 years of age) and 61 older (65–75 years of age) participants were tested in an immersive driving simulator. They followed a car that occasionally slowed down and concurrently executed a mixed sequence of loading tasks that differed with respect to their sensory input modality, cognitive requirements and motor output channel. In two control conditions, the car-following or the loading task were administered alone. Older participants drove more slowly, more laterally and more variably than young ones, and this age difference was accentuated in the multitask-condition, particularly if the loading task took participants’ gaze and attention away from the road. In the latter case, 78% of older drivers veered off the road and 15% drove across the median. The corresponding values for young drivers were 40% and 0%, respectively. Our findings indicate that multitasking deteriorates in older age not only in typical laboratory paradigms, but also in paradigms that require orchestration of dual-tasking and task switching. They also indicate that older drivers are at a higher risk of causing an accident when they engage in a task that takes gaze and attention away from the road.
Laboratory-based research revealed that gait involves higher cognitive processes, leading to performance impairments when executed with a concurrent loading task. Deficits are especially pronounced in older adults. Theoretical approaches like the multiple resource model highlight the role of task similarity and associated attention distribution problems. It has been shown that in cases where these distribution problems are perceived relevant to participant's risk of falls, older adults prioritize gait and posture over the concurrent loading task. Here we investigate whether findings on task similarity and task prioritization can be transferred to an ecologically valid scenario. Sixty-three younger adults (20–30 years of age) and 61 older adults (65–75 years of age) participated in a virtual street crossing simulation. The participants' task was to identify suitable gaps that would allow them to cross a simulated two way street safely. Therefore, participants walked on a manual treadmill that transferred their forward motion to forward displacements in a virtual city. The task was presented as a single task (crossing only) and as a multitask. In the multitask condition participants were asked, among others, to type in three digit numbers that were presented either visually or auditorily. We found that for both age groups, street crossing as well as typing performance suffered under multitasking conditions. Impairments were especially pronounced for older adults (e.g., longer crossing initiation phase, more missed opportunities). However, younger and older adults did not differ in the speed and success rate of crossing. Further, deficits were stronger in the visual compared to the auditory task modality for most parameters. Our findings conform to earlier studies that found an age-related decline in multitasking performance in less realistic scenarios. However, task similarity effects were inconsistent and question the validity of the multiple resource model within ecologically valid scenarios.
Virtual reality technology can be used for ecologically valid assessment and rehabilitation of cognitive deficits. This article expands the scope of applications to ecologically valid multitasking. A commercially available driving simulator was upgraded by adding an ever-changing sequence of concurrent, everyday-like tasks. Furthermore, the simulator software was modified and interfaced with a non-motorized treadmill to yield a pedestrian street crossing simulator. In the latter simulator, participants walk on through a virtual city, stop at busy streets to wait for a gap in traffic, and then cross. Again, a sequence of everyday-like tasks is added. A feasibility study yielded adequate “presence” in both virtual scenarios, and plausible data about performance decrements under multi-task compared to single-task conditions. The present approach could be suitable for the assessment and training of multitasking skills in older adults and neurological patients.
Human multitasking has been evaluated with paradigms that administered two—rarely three—concurrent tasks. In everyday life, however, we usually face an ever-changing sequence of distinct concurrent tasks. Available studies therefore provided valuable insights into our ability for dual tasking, but they did not address the natural interplay of dual tasking and task switching. The present study was undertaken to explore the feasibility of two new paradigms which replicate that interplay in virtual reality. We used car driving simulator software to implement a virtual car-driving task as well as a virtual street-crossing task. Either task was administered alone, as well as concurrently with a battery of loading tasks that mimicked activities of everyday life. The loading tasks used different sensory modalities, different cognitive processes, and different output channels and were presented in an ever-changing sequence. Cronbach’s alpha scores of key registered variables were high, which indicates that our approach is reliable. Driving and street-crossing performance deteriorated under multitask conditions, which indicates that our approach is sensitive to multitasking. This is the first study to demonstrate the feasibility of an experimental paradigm for the assessment of natural multitasking, i.e., of combined dual tasking and task switching. This paradigm could be of interest for basic science as well as for prevention and rehabilitation settings.
Numerous studies showed decreased performance in situations that require multiple tasks or actions relative to appropriate control conditions. Because humans often engage in such multitasking activities, it is important to understand how multitasking affects performance. In the present article, we argue that research on dual-task interference and sequential task switching has proceeded largely separately using different experimental paradigms and methodology. In our article we aim at organizing this complex set of research in terms of three complementary research perspectives on human multitasking. One perspective refers to structural accounts in terms of cognitive bottlenecks (i.e., critical processing stages). A second perspective refers to cognitive flexibility in terms of the underlying cognitive control processes. A third perspective emphasizes cognitive plasticity in terms of the influence of practice on human multitasking abilities. With our review article we aimed at highlighting the value of an integrative position that goes beyond isolated consideration of a single theoretical research perspective and that broadens the focus from single experimental paradigms (dual task and task switching) to favor instead a view that emphasizes the fundamental similarity of the underlying cognitive mechanisms across multitasking paradigms.
Police records represent the primary source of data on the role of driver distraction in crashes. It is commonly assumed that officers attending the crash scene tend to underreport driver distraction as a contributing factor in crashes. However, this assumption has never been explicitly tested. Thus, the goal of this study was to empirically estimate the presence of underreporting bias of driver distraction in police crash reports. We also explored whether such underreporting vary with respect to the age and gender of the driver. To this end, we presented police officers with hypothetical crash scenarios involving drivers from different age and gender groups. For each scenario, officers estimated the possible factors they believed to have contributed to the collision. We assessed the under-reporting of distraction-related crashes by comparing police officers’ views with real crash reports. Our findings show that officers more often viewed distractive behaviours inside the vehicle as a cause of collisions than was evident in the crash reports. This difference was particularly pronounced with respect to mobile phone use as a cause of crashes. In contrast, officers’ views and accidents records were similar with regard to the involvement of outside-vehicle distraction in crashes. Overall, the results substantiate claims that police reports do not provide reliable information on the role of driver distraction in crashes. In particular, the dangers of mobile phone use whilst driving have been severely underestimated.
Texting and other cell-phone related distracted driving is estimated to account for thousands of motor vehicle collisions each year but studies examining the specific cell phone reading and writing activities of drivers are limited. The objective of this study was to describe the frequency of cell-phone related distracted driving behaviors. A national, representative, anonymous panel of 1211 United States drivers was recruited in 2015 to complete the Distracted Driving Survey (DDS), an 11-item validated questionnaire examining cell phone reading and writing activities and at what speeds they occur. Higher DDS scores reflect more distraction. DDS scores were analyzed by demographic data and self-reported crash rate.Nearly 60% of respondents reported a cell phone reading or writing activity within the prior 30 days, with reading texts (48%), writing texts (33%) and viewing maps (43%) most frequently reported. Only 4.9% of respondents had enrolled in a program aimed at reducing cell phone related distracted driving. DDS scores were significantly correlated to crash rate (p < 0.0001), with every one point increase associated with an additional 7% risk of a crash (p < 0.0001). DDS scores were inversely correlated to age (p < 0.0001).The DDS demonstrated high internal consistency (Cronbach's alpha = 0.94).High rates of cell phone-related distraction are reported here in a national sample. Distraction is associated with crash rates and occurs across all age groups, but is highest in younger drivers.The DDS can be used to evaluate the impact of public health programs aimed at reducing cell-phone related distracted driving.
With the increasing aging of the population, the number of older drivers is rising. Driving is a significant factor for quality of life and independence concerning social and working life. On the other hand, driving is a complex task involving visual, motor, and cognitive skills that experience age-related changes even in healthy aging. In this review we summarize different age-related functional changes with relevance for driving concerning sensory, motor, and cognitive functions. Since these functions have great interindividual variability, it is necessary to apply methods that help to identify older drivers with impaired driving abilities in order to take appropriate measures. We discuss three different methods to assess driving ability, namely the assessment of (i) functions relevant for driving; (ii) driving behavior in real traffic; and (iii) behavior in a driving simulator. We present different measures to improve mobility in older drivers, including information campaigns, design of traffic and car environment, instructions, functional training, and driving training in real traffic and in a driving simulator. Finally, we give some recommendations for assessing and improving the driving abilities of older drivers with multi-modal approaches being most promising for enhancing individual and public safety.
Significance
This paper presents findings about the riskiest factors faced by drivers as informed through the first large-scale, crash-only analysis of naturalistic driving data. Results indicate that many secondary tasks or activities, particularly resulting from the use of handheld electronic devices, are of detriment to driver safety. The analysis uses a large naturalistic database comprising continuous in situ observations made via multiple onboard video cameras and sensors that gathered information from more than 3,500 drivers across a 3-y period.
Driving a motor vehicle requires various cognitive functions to process surrounding information, to guide appropriate actions, and especially to respond to or integrate with numerous contextual and perceptual hindrances or risks. It is, thus, imperative to examine driving performance and road safety from a perspective of cognitive neuroscience, which considers both the behaviour and the functioning of the brain. However, because of technical limitations of current brain imaging approaches, studies have primarily adopted driving games or simulators to present participants with simulated driving environments that may have less ecological validity. Near-infrared spectroscopy (NIRS) is a relatively new, non-invasive brain-imaging technique allowing measurement of brain activations in more realistic settings, even within real motor vehicles. This study reviews current NIRS driving research and explores NIRS' potential as a new tool to examine driving behaviour, along with various risk factors in natural situations, promoting our understanding about neural mechanisms of driving safety. Practitioner Summary: Driving a vehicle is dependent on a range of neurocognitive processing abilities. Near-infrared spectroscopy (NIRS) is a non-invasive brain-imaging technique allowing measurement of brain activation even in on-road studies within real motor vehicles. This study reviews current NIRS driving research and explores the potential of NIRS as a new tool to examine driving behaviour.
In an investigation of task-set reconfiguration, participants switched between 2 tasks on every 2nd trial in 5 experiments and on every 4th trial in a final experiment. The tasks were to classify either the digit member of a pair of characters as even/odd or the letter member as consonant/vowel. As the response–stimulus interval increased up to 0.6 s, the substantial cost to performance of this predictable task-switch fell: Participants could partially reconfigure in advance of the stimulus. However, even with 1.2 s available for preparation, a large asymptotic reaction time (RT) cost remained, but only on the 1st trial of the new task. This is attributed to a component of reconfiguration triggered exogenously, i.e., only by a task-relevant stimulus. That stimuli evoke associated task-sets also explains why RT and switch costs increased when the stimulus included a character associated with the currently irrelevant task. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Driver distraction by in-vehicle tasks has a negative impact on driving performance and crash risk. This paper describes a study investigating the effect of interacting with a surrogate in-vehicle system task -- requiring a two-choice speeded response -- in close temporal proximity to a subsequent lead vehicle braking event. The purpose of the study was to determine the 'task-free' interval required before a braking event to ensure safe braking performance. Drivers (N = 48) were split into six groups and randomly assigned an in-vehicle task defined by stimulus (three levels) and response modality (two levels). Four blocks of intermixed single- and dual-task trials were presented. The time interval between the two tasks was varied on dual-task trials. Slower braking responses on dual-task trials relative to single-task trials indicated dual-task interference. Driver braking performance demonstrated the psychological refractory period effect -- an increase in reaction time with decreasing temporal separation of the two tasks. The impact of in-vehicle task stimulus and response modality on performance is discussed in relation to predictions based on Multiple Resource Theory. This study demonstrates a fundamental human performance limitation in the real-world driving context and has implications for driver response speeds when distracted. Specifically, the presentation of an in-vehicle task in the 350 milliseconds before a braking event could have severe safety consequences. The use of the findings to manage in-vehicle stimulus presentation is discussed. Problems with implementation of the results are reported.
This research aims to identify the impact of text messaging on simulated driving performance.
In the past decade, a number of on-road, epidemiological, and simulator-based studies reported the negative impact of talking on a cell phone on driving behavior. However, the impact of text messaging on simulated driving performance is still not fully understood.
Forty participants engaged in both a single task (driving) and a dual task (driving and text messaging) in a high-fidelity driving simulator.
Analysis of driving performance revealed that participants in the dual-task condition responded more slowly to the onset of braking lights and showed impairments in forward and lateral control compared with a driving-only condition. Moreover, text-messaging drivers were involved in more crashes than drivers not engaged in text messaging.
Text messaging while driving has a negative impact on simulated driving performance. This negative impact appears to exceed the impact of conversing on a cell phone while driving.
The results increase our understanding of driver distraction and have potential implications for public safety and device development.
To establish the association between impaired vision and drivers' decisions to stop driving, voluntarily restrict driving, and motor vehicle accidents.
Driving related questions were included in a population based study that determined the prevalence and incidence of eye disease. Stratified random cluster samples based on census collector districts were selected from the Melbourne Statistical Division. Eligible participants aged 44 years and over were interviewed and underwent a comprehensive ophthalmic examination. The outcomes of interest were the decision to stop driving, limiting driving in specified conditions, and driving accidents. The associations between these outcomes and the legally prescribed visual acuity (<6/12) for a driver's licence were investigated.
The mean age of the 2594/3040 (85%) eligible participants was 62.5 (range 44-101). People with visual acuity less than 6/12 were no more likely to have an accident than those with better vision (chi(2) = 0.175, p>0.9). Older drivers with impaired vision, more so than younger adults, restrict their driving in visually demanding situations (p<0.05). Of the current drivers, 2.6% have vision less than that required to obtain a driver's licence. The risk of having an accident increased with distance driven (OR 2.57, CL 1.63, 4.04 for distance >31 000 km) but not with age.
There was no greater likelihood of self reported driving accidents for drivers with impaired vision than those with good vision. While many older drivers with impaired vision limit their driving in adverse conditions and some drivers with impaired vision stop driving, there are a significant number of current drivers with impaired vision.
This research examined the effects of hands-free cell phone conversations on simulated driving. The authors found that these conversations impaired driver's reactions to vehicles braking in front of them. The authors assessed whether this impairment could be attributed to a withdrawal of attention from the visual scene, yielding a form of inattention blindness. Cell phone conversations impaired explicit recognition memory for roadside billboards. Eye-tracking data indicated that this was due to reduced attention to foveal information. This interpretation was bolstered by data showing that cell phone conversations impaired implicit perceptual memory for items presented at fixation. The data suggest that the impairment of driving performance produced by cell phone conversations is mediated, at least in part, by reduced attention to visual inputs.
Driver distraction is one major cause of road traffic accidents. In order to avoid distraction-related accidents it is important to inhibit irrelevant stimuli and unnecessary responses to distractors and to focus on the driving task, especially when unpredictable critical events occur. Since inhibition is a cognitive function that develops until young adulthood and decreases with increasing age, young and older drivers should be more susceptible to distraction than middle-aged drivers. Using a driving simulation, the present study investigated effects of acoustic and visual distracting stimuli on responses to critical events (flashing up brake lights of a car ahead) in young, middle-aged, and older drivers. The task difficulty was varied in three conditions, in which distractors could either be ignored (perception-only), or required a simple response (detection) or a complex Go-/NoGo-response (discrimination). Response times and error rates to the critical event increased when a simultaneous reaction to the distractor was required. This distraction effect was most pronounced in the discrimination condition, in which the participants had to respond to some of the distracting stimuli and to inhibit responses to some other stimuli. Visual distractors had a stronger impact than acoustic ones. While middle-aged drivers managed distractor inhibition even in difficult tasks quite well (i.e., when responses to distracting stimuli had to be suppressed), response times of young and old drivers increased significantly, especially when distractor stimuli had to be ignored. The results demonstrate the high impact of distraction on driving performance in critical traffic situations and indicate a driving-related inhibition deficit in young and old drivers.
Objective: This study investigated the contribution of driver distraction and inattention within fatal and injury crashes using recent in-depth road crash investigation data. To assist in developing system-based solutions, this study also examined the wider context in which inattention-related crashes occurred and the characteristics of inattentive drivers.
Methods: The sample included in-depth crash data from 186 fatal and injury crashes in South Australia investigated from 2014 to 2018. Crash case notes were reviewed to determine whether there was evidence that attentional failures contributed to the crash. Using an adapted taxonomy of inattention, 5 subtypes of driver inattention were defined: Misprioritized attention, neglected attention, cursory attention, diverted attention (distraction), and unspecified inattention. The characteristics of inattention crashes were also compared with those for non-inattention-related crashes.
Results: Of the 160 crashes for which there was sufficient information to determine whether inattention was a factor, 31.3% showed evidence of driver inattention contributing to the crash. The most common subtypes of inattention were distraction (13.8% of all crashes) and driver misprioritized attention (8.1%). The distraction-related crashes included a variety of different distractions, the majority of which were not technology based (e.g., passenger interaction, searching for/adjusting objects, emotional stress, other road users), with those located in-vehicle the most prevalent. Distraction from mobile phone use was identified in 2.5% of all crashes. The majority of distractions were cognitive (64%) and voluntary (77%) in nature. Inattention crashes were most likely to involve right turn/angle or rear-end crash types and occur at intersections, in metropolitan areas, and in lower speed zones.
Conclusions: The findings established that almost a third of fatal and injury crashes involved driver inattention and distraction and many of these could have been prevented. System-wide solutions that could mitigate or prevent distraction crashes include intervening vehicle safety technologies, infrastructure solutions to promote a forgiving road environment, blocking capabilities within technologies to prevent communications while driving, and interventions communicating the risks associated with inattention. Of significance, this study also demonstrated the importance of in-depth data for understanding the contribution of distraction and inattention errors in crash causation.
With the aging of the population the issue of older drivers safety has gained importance in recent years. Age-related cognitive decline is frequently cited as the main cause of unsafe driving performance in older drivers. Objective: The present study investigated how executive functions (EFs), measured as latent variables, are related to on-road driving performance during aging. Method: One hundred and twenty-six participants aged from twenty to eighty-two, completed a two hundred and forty-seven km on-road driving test and a set of executive tasks selected to tap three often postulated EFs: inhibition (inhibiting prepotent responses), updating (updating working memory representations), and shifting (shifting task sets). Results: Confirmatory factor analysis reproduces previous results obtained by Miyake et al. (2000), Miyake and Friedman (2012) of unity and diversity of EFs in an adult life span sample. Structural equation modeling suggested that on-road driving performance was related to inhibition. Furthermore, findings indicate that the age-related driving performance decline in normal aging may be mediated by the inhibition function. Conclusions: The results highlight the importance of a proper method to assess executive functioning in a specific domain as well as emphasising the major role of those functions in driving performance while aging.
[Background and Objectives]
Mobility is a critical factor that influences older adults’ independence and well-being. Older drivers may experience increased crash risks due to age-related cognitive declines. Ensuring safe driving practices among older drivers is important to maintain their mobility without sacrificing safety. Investigations for an effective assessment technology that can inform older drivers’ risks associated with cognitive declines are warranted. This study aims to identify attentional deteriorations that may underlie crashes in various situations.
[Research Design and Methods]
This study employed driving simulation to examine associations between attentional functions of older drivers and crash risks in various hazardous situations. Using the Attention Network Test (ANT), a computerized assessment that measures efficiencies of the three distinct attentional functions (i.e., alerting, orienting, and executive), we examined specific attentional functions that underlie older drivers’ crash risks in particular driving situations.
[Results]
Findings from this study revealed significant associations between executive attentional efficiency and crash risks in situations that demand a driver quickly resolving conflicts among multiple competing tasks or information. These situations include turning while a pedestrian is crossing from an opposite direction, merging, and multitasking while driving.
[Discussion and Implications]
The present findings expand our understanding of unique involvements of attentional functions in particular driving situations at an old age. Future driver assessment technologies for informing older drivers about their crash risks may aim to address more fundamental cognitive mechanisms that lead to elevated risks in particular driving situations rather than merely focusing on the situations themselves.
This paper investigates the effect that texting with WhatsApp, one of the most common applications for instant messaging, exerts on driving performance. Because distracted driving also affects older drivers, who can have seriously compromised vision, we also analysed the associations between visual-function parameters and driving performance. A total of 75 drivers, experienced in sending WhatsApp messages (≥10WhatsApp messages/week), participated in this study and were divided into four age categories. Visual-function tests included contrast sensitivity with and without glare, retinal straylight and objective assessment of optical quality. Simulated driving performance was assessed under a baseline driving condition (without distraction) as well as a texting condition (WhatsApp messages) while driving. The participants used their own mobile phone. Lastly, objective results of driving performance were compared with subjective self-report data from the Driver Behaviour Questionnaire (DBQ). The analysis indicated that functional changes occurring with age, such as a lower contrast sensitivity and greater retinal straylight, were correlated with a higher number of collisions, longer distances driven outside the lane, and greater standard deviation of lateral position (SDLP). The results showed a significant main effect of age for the driving-performance parameters. Also, compared to the baseline, texting WhatsApp messages while driving worsens driving performance for all age groups, most notably among older participants. Thus, the older drivers' SDLP was ∼14% higher than that for the baseline average of all the other drivers and rose to 29% under distraction, reflecting the impact of secondary tasks. The negative effect of the use of the smartphone during driving was also reflected in the number of collisions, with a greater risk of accidents in all the groups of drivers (by 8.3% for young adults, 25.0% for adults, 80.5% for middle-aged adults, and 134.5% for older drivers). Lastly, participants' subjective responses indicated that younger drivers (18-24 years) had a higher risk of deliberately violating safe driving practices (p < 0.05). The present study demonstrates that texting WhatsApp messages while driving significantly impairs the ability to drive safely, with older drivers being the group most adversely affected. It would be recommendable to include other nonstandard vision tests, which have shown associations with driving performance, in the examination for driver licensing. This would help raise the awareness of older drivers concerning their visual limitations, permitting them to adopt compensatory measures to improve their driving safety. Nevertheless, it is also necessary to raise awareness among the younger drivers of the risks involved in behaviour behind the wheel.
Objective: The adaptive behaviour of mobile phone distracted drivers has been a topic of much discussion in the recent literature. Both simulator and naturalistic studies suggests that distracted drivers generally select lower driving speeds; however, speed adaptation is not observed among all drivers, and the mechanisms of speed selection are not well understood. The aim of this research was to apply a driver behavioural adaptation model to investigate the speed adaptation of mobile phone distracted drivers.
Methods: The speed selection behaviour of drivers was observed in three phone conditions including baseline (no conversation), hands-free and handheld phone conversations in a high-fidelity driving simulator. Speed adaptation in each phone condition was modelled as a function of secondary task demand and self-reported personal/psychological characteristics with a system of seemingly unrelated equations (SURE) accounting for potential correlations due to repeated measures experiment design.
Results: Speed adaptation is similar between hands-free and handheld phone conditions, but the predictors of speed adaptation vary across the phone conditions. While perceived workload of secondary task demand, self-efficacy, attitude towards safety, and driver demographics were significant predictors of speed adaptation in the handheld condition, drivers’ familiarity with the hands-free interface, attitude towards safety, and sensation seeking were significant predictors in the hands-free condition. Drivers who reported more positive safety attitudes selected lower driving speeds while using phones.
Conclusion: This research confirmed that behavioural adaptation models are suitable for explaining speed adaptation of mobile phone distracted drivers, and future research could be focused on further theoretical refinement.
Background
Driver distraction is a major contributing factor to crashes, which are the leading cause of death for the US population under 35 years of age. The prevalence of secondary-task engagement and its impacts on distraction and crashes may vary substantially by driver age.
Methods
Driving performance and behaviour data were collected continuously using multiple cameras and sensors in situ for 3542 participant drivers recruited for up to 3 years for the Second Strategic Highway Research Program Naturalistic Driving Study. Secondary-task engagement at the onset of crashes and during normal driving segments was identified from videos. A case–cohort approach was used to estimate the crash odds ratios associated with, and the prevalence of, secondary tasks for four age groups: 16–20, 21–29, 30–64 and 65–98 years of age. Only severe crashes (property damage and higher severity) were included in the analysis.
Results
Secondary-task-induced distraction posed a consistently higher threat for drivers younger than 30 and above 65 when compared with middle-aged drivers, although senior drivers engaged in secondary tasks much less frequently than their younger counterparts. Secondary tasks with high visual–manual demand (e.g. visual–manual tasks performed on cell phones) affected drivers of all ages. Certain secondary tasks, such as operation of in-vehicle devices and talking/singing, increased the risk for only certain age groups.
Conclusions
Teenaged, young adult drivers and senior drivers are more adversely impacted by secondary-task engagement than middle-aged drivers. Visual–manual distractions impact drivers of all ages, whereas cognitive distraction may have a larger impact on young drivers.
Performing secondary tasks, such as texting while driving, is associated with an increased risk of motor vehicle collisions (MVCs). While cognitive processes, such as executive function, are involved in driving, little is known about the relationship between executive control and willingness to engage in distracted driving. This study investigated the relationship between age, behavioral manifestations of executive function, and self-reported distracted driving behaviors. Executive difficulty (assessed with the BRIEF-A) as well as demographics (age and gender) was considered as possible predictors of engagement in distracted driving behaviors. Fifty-nine young, middle, and older adults self-reported executive difficulty and weekly engagement in distracted driving behaviors. Results revealed that while partially accounted for by age, global executive difficulty was uniquely related to engagement in distracted driving behaviors. Older age was associated with fewer weekly self-reported distracted driving behaviors while higher self-reported executive difficulty was associated with more frequent weekly engagement in distracted behavior. No significant differences were found between young and middle-aged adults on distracted driving behaviors. Findings conclude that distracted driving is a ubiquitous phenomenon evident in drivers of all ages. Possible mechanisms underlying distracted driving behavior could potentially be related to deficits in executive function.
This chapter is divided into two parts. The first describes the effect of Pat Rabbitt's influence in encouraging the first author to use the increasingly sophisticated methods of ageing research to answer questions about the fundamental characteristics of working memory, together with reflections on why so little of this work reached publication. The second part presents a brief review of the literature on working memory and ageing, followed by an account of more recent work attempting to apply the traditional method of experimental dissociation to research on normal ageing and Alzheimer's disease. The discussion suggests that even such simple methods can throw light on both the processes of ageing and the understanding of working memory.
This study evaluated the impact of the modality of distractor tasks and the difficulty of the driving task on driver control over a vehicle. Driving is a task with a close link between visual information processing and driver performance variables such as lane keeping. Consequently, compared to auditory distractors, visual distractors should have a larger negative effect on vehicle control, but mainly when the driving task also adds significant workload for the driver. In this study, drivers drove around either a curvy or a straight track while occasionally performing either an auditory or a visual secondary monitoring task. Performance of the secondary task was associated with deterioration in steering wheel control and lane keeping, but only on the curvy track and mainly when the secondary task required visual monitoring. These results are discussed in terms of their implication for developing workload managers in in-vehicle driver support systems.
This paper reports a simulator-based study of the effects of mobile phone use on driving performance. Changes in heart rate indicated that mobile phone use increases the cognitive demand experienced by drivers with, it is argued, consequent reduction in safety margins. However, experimental results also suggested that participants engaged in a process of risk compensation, with driving speed being slower at times of mobile phone conversation while the number of off-road excursions (OFFS) and collisions remained stable. There also was some evidence that the use of a hand-held mobile phone (when compared to a hands-free system) was associated with poorer driving performance. Implications for `real world' driving are considered.
Driving performance in an instrumented vehicle was compared with performance in a low-cost, fixed-based driving simulator. Six men and six women drove a freeway route while periodically dialling simulated phone calls. The same subjects drove a laboratory driving simulator using two visual fidelity levels: a colour scene with relatively high detail, and a monochrome (night) scene showing only road-edge markings. Lane position, speed, steering-wheel angle and throttle position were recorded in both contexts. Lane-keeping in the simulator was less precise than on the road, but speed control performance was comparable. The SD of lane position in normal driving was about twice as large, on average, in the simulator (0.360 versus 0.165 m). Lane keeping and speed control were less precise when dialling the phone than in normal driving, both in the simulator and on the road, but the performance decrement was greater in the simulator. The addition of the phone task increased the mean lateral speed in the car by about 43%, while in the simulator the mean lateral speed increased by 158% with the addition of the phone task. Subjects >60 years of age showed larger performance decrements during a concurrent phone dialling task than did subjects 20–30 years of age both in the simulator and on-road. No important differences in driving performance were found between the high and low simulator scene fidelity levels. The simulator demonstrated good absolute validity for measures of speed control and good relative validity for the effects of the phone task and age on driving precision.
The experiment outlined in this paper investigated the effect of interference on everyday dynamic risk-taking judgments. Two questions were addressed. First, can highly practised dynamic risk-taking decisions become automated, such that they are not affected by the presence of a demanding secondary task? Second, if risk-taking decisions are interfered with by a secondary task, what is the direction of the effect? Do people take more risks when they are distracted or do they compensate for the interference and take fewer risks? Drivers (N=121) were required to perform video-simulation tests measuring driving-related, risk-taking decisions. Participants were required to carry out the tasks while either performing a concurrent verbal task or not. It was found that those in the dual-task condition took more risks. This suggests that dynamic risk-taking decisions in this context are not automatic and also that interference increases individuals propensity to take risks.
This project used an internet survey of 287 Victorian drivers to quantify the extent to which drivers reportedly engage in a range of potentially distracting activities; the factors that influence their willingness to engage; and the strategies they use, if any, to manage distraction. Almost 60% of drivers use a mobile phone while driving and over one third use the phone in hand-held mode. A high proportion of drivers use audio entertainment systems, but relatively few use in-vehicle visual displays such as DVD players. Driver engagement in non-technology-based activities, such as eating, drinking, smoking and reading is also prevalent. Young drivers (18–25 yrs) were significantly more likely to report engaging in certain distracting activities, such as using a mobile phone, CD player and eating and drinking, than their middle-age (26–54 yrs) and older (55+ yrs) counterparts. Most drivers (84%) believe that their driving is less safe when engaged in distracting tasks and take steps to avoid distraction. The survey results provide valuable data to help target distraction policy and countermeasures that build upon the self-regulatory strategies already used by some drivers.
Heart rate and driving performance were assessed while late middle age (51-66) and younger adults (19-23) engaged in a naturalistic hands free phone task that was designed to place objectively equivalent cognitive demands on all participants. Although heart rate measures have been used in evaluating driver workload, prior studies had not compared responses in late middle age and younger adults with samples of sufficient size to begin to explore possible age relationships. In an evaluation of 37 participants, the two age groups displayed equivalent performance on the cellular telephone task and concurrent decrements in speed control (SD velocity). It was observed that the late middle age subjects drove more slowly overall and, as a group, did not demonstrate heart rate acceleration in response to the phone conversation that was seen in younger drivers. The possibility that age group differences in heart rate response are related to individual differences in attentional focus is raised. While there are significant reasons to discourage all individuals from engaging in phone conversations and other distracting tasks while driving, late middle age adults appeared as capable as young adults of managing the additional workload of a low to moderately demanding cognitive task of the type assessed. The tendency of individuals to adopt self-regulatory behaviors, such as a lower overall driving speed, as a function of age / experience may account for the equivalence in overt performance.
We examined trends in distracted driving fatalities and their relation to cell phone use and texting volume.
The Fatality Analysis Reporting System (FARS) records data on all road fatalities that occurred on public roads in the United States from 1999 to 2008. We studied trends in distracted driving fatalities, driver and crash characteristics, and trends in cell phone use and texting volume. We used multivariate regression analysis to estimate the relation between state-level distracted driving fatalities and texting volumes.
After declining from 1999 to 2005, fatalities from distracted driving increased 28% after 2005, rising from 4572 fatalities to 5870 in 2008. Crashes increasingly involved male drivers driving alone in collisions with roadside obstructions in urban areas. By use of multivariate analyses, we predicted that increasing texting volumes resulted in more than 16,000 additional road fatalities from 2001 to 2007.
Distracted driving is a growing public safety hazard. Specifically, the dramatic rise in texting volume since 2005 appeared to be contributing to an alarming rise in distracted driving fatalities. Legislation enacting texting bans should be paired with effective enforcement to deter drivers from using cell phones while driving.
Due to the high prevalence of mild cognitive impairment (MCI) and dementia in Parkinson disease (PD), routine cognitive screening is important for the optimal management of patients with PD. The Montreal Cognitive Assessment (MoCA) is more sensitive than the commonly used Mini-Mental State Examination (MMSE) in detecting MCI and dementia in patients without PD, but its validity in PD has not been established.
A representative sample of 132 patients with PD at 2 movement disorders centers was administered the MoCA, MMSE, and a neuropsychological battery with operationalized criteria for deficits. MCI and PD dementia (PDD) criteria were applied by an investigator blinded to the MoCA and MMSE results. The discriminant validity of the MoCA and MMSE as screening and diagnostic instruments was ascertained.
Approximately one third of the sample met diagnostic criteria for a cognitive disorder (12.9% PDD and 17.4% MCI). Mean (SD) MoCA and MMSE scores were 25.0 (3.8) and 28.1 (2.0). The overall discriminant validity for detection of any cognitive disorder was similar for the MoCA and the MMSE (receiver operating characteristic area under the curve [95% confidence interval]): MoCA (0.79 [0.72, 0.87]) and MMSE (0.76 [0.67, 0.85]), but as a screening instrument the MoCA (optimal cutoff point = 26/27, 64% correctly diagnosed, lack of ceiling effect) was superior to the MMSE (optimal cutoff point = 29/30, 54% correctly diagnosed, presence of ceiling effect).
The Montreal Cognitive Assessment, but not the Mini-Mental State Examination, has adequate psychometric properties as a screening instrument for the detection of mild cognitive impairment or dementia in Parkinson disease. However, a positive screen using either instrument requires additional assessment due to suboptimal specificity at the recommended screening cutoff point.
Teenage novice drivers have elevated crash rates compared with more experienced drivers. This study examined the hypothesis that driving accidents in young adults are associated with individual and developmental differences in prefrontally-mediated executive control functions. High-school students completed a simulated driving task and six experimental tasks that tapped three basic components of executive functioning (response inhibition, working memory updating, and mental shifting). Individual differences in executive functioning were related to simulated driving performance, and these effects were selective in that the updating component of executive functioning was the primary predictor of driving performance. Furthermore, the observed effects were accentuated in participants with minimal experience of computer games, suggesting that computer game skills compensated for inefficient working memory functions. The results of this study suggest that individual and developmental differences in executive functions contribute to driving accidents in young adults.
The effects of telephoning while driving were studied in three different traffic conditions, i.e. in light traffic on a quiet motorway, in heavy traffic on a four-lane ring-road, and in city traffic. Twelve subjects, unfamiliar with mobile telephones, drove an instrumented vehicle for one hour each day during three weeks and while in each of the three traffic conditions, had to operate the mobile telephone for a short while. To ensure a fixed "heavy traffic load" in the second condition, the subjects were instructed to follow another instrumented vehicle (at a safe distance). The results showed a significant effect of telephoning while driving as opposed to normal driving (i.e., not involving telephone conversation), on the effort subjectively measured by an effort scale and objectively measured by heartrate indices and on some of the measured parameters of driving performance. One half of the subjects had to operate the telephone manually, the other half performed the telephone task with a handsfree mobile telephone set. The subjects who operated the handsfree telephone showed better control over the test vehicle than the subjects who operated the handheld telephone, as measured by the steering wheel movements. Also, a clear improvement over time in the course of the 15 test days was found for some of the measurements. As a consequence of the results, some advice concerning mobile telephoning can be given to authorities, manufacturers, and users.
The need for a simply applied quantitative assessment of handedness is discussed and some previous forms reviewed. An inventory of 20 items with a set of instructions and response- and computational-conventions is proposed and the results obtained from a young adult population numbering some 1100 individuals are reported. The separate items are examined from the point of view of sex, cultural and socio-economic factors which might appertain to them and also of their inter-relationship to each other and to the measure computed from them all. Criteria derived from these considerations are then applied to eliminate 10 of the original 20 items and the results recomputed to provide frequency-distribution and cumulative frequency functions and a revised item-analysis. The difference of incidence of handedness between the sexes is discussed.
The effects of a mobile telephone task on drivers' reaction time, lane position, speed level, and workload were studied in two driving conditions (an easy or rather straight versus a hard or very curvy route). It was predicted that the mobile telephone task would have a negative effect on drivers' reaction time, lane position, and workload and lead to a reduction of speed. It was also predicted that the effects would be stronger for the hard driving task. The study was conducted in the VTI driving simulator. A total of 40 subjects, experienced drivers aged 23 to 61, were randomly assigned to four experimental conditions (telephone and easy or hard driving task versus control and easy or hard driving task). Contrary to the predictions, the strongest effects were found when the subjects were exposed to the easy driving task. In the condition where drivers had to perform the easy driving task, findings showed that a mobile telephone task had a negative effect on reaction time and led to a reduction of the speed level. In the condition where drivers had to perform the hard driving task, findings showed that a mobile telephone task had an effect only on the drivers' lateral position. Finally, the mobile telephone task led to an increased workload for both the easy and the hard driving task. The results are discussed in terms of which subtask, car driving or telephone task, the subjects gave the highest priority. Some implications for information systems in future cars are discussed.
The logic of generalized slowing theories is explored. Existing theories are reviewed briefly and put in a common format. The format is readily generalized to define a class of one-dimensional aging theories, a tiny subset of all possible aging theories. A corresponding class of compatible data is demonstrated, in terms of allowable configurations of a Brinley plot. Nonconforming configurations have the force of disconfirming the entire class of aging theories. Information processing theories can be cast in a similar format. It is shown that, for a slowing theory to be indisputably general, it must be associated with a multidimensional information processing theory.
In this study, 150 subjects observed a 25-minute video driving sequence containing 45 highway traffic situations to which they were expected to respond by manipulation of simulated vehicle controls. Each situation occurred under five conditions of distraction: placing a cellular phone call, carrying on a causal cellular phone conversation, carrying on an intense cellular phone conversation, tuning a radio, and no distraction. All of the distractions led to significant increases in the proportion of situations to which subjects failed to respond. However, significant age differences of nonresponse appeared. Among subjects over age 50, nonresponses increased by about one-third under all of the telephone distractions. The response rate of younger subjects increased by a lesser degree except under intense conversation. Results were not influenced by gender or prior experience with cellular phones. The authors conclude that older drivers might reduce their accident risk during attention-demanding traffic conditions by avoiding use of cellular phones and that other drivers might do so by refraining from calls involving intense conversation.
The effects of a mobile telephone task on young and elderly drivers' choice reaction time, headway, lateral position, and workload were studied when the subjects were driving in a car-following situation, in the VTI driving simulator. It was found that a mobile telephone task had a negative effect upon the drivers' choice reaction time, and that the effect was more pronounced for the elderly drivers. Furthermore, the subjects did not compensate for their increased reaction time by increasing their headway during the phone task. The subjects' mental workload, as measured by the NASA-TLX, increased as a function of the mobile telephone task. No effect on the subjects' lateral position could be detected. Taken together, these results indicate that the accident risk can increase when a driver is using the mobile telephone in a car following situation. The reasons for the increased risk, and possible ways to eliminate it, are also discussed.
This study was aimed at investigating drivers' ability to detect a car ahead decelerating, while doing mobile phone related tasks. Nineteen participants aged between 20 and 29 years, (2000-125000 km driving experience) drove at 80 km/h, 50 m behind a lead car, on a 30 km section of motorway in normal traffic. During each trial the lead car started to decelerate at an average of 0.47 m/s2 while the participant either looked at the car in front (control), continuously dialed series of three random integers on a numeric keypad (divided visual attention), or performed a memory and addition task (non-visual attention). The results indicated that drivers' detection ability was impaired by about 0.5 s in terms of brake reaction time and almost 1 s in terms of time-to-collision, when they were doing the non-visual task whilst driving. This impairment was similar to when the drivers were dividing their visual attention between the road ahead and dialing numbers on the keypad. It was concluded that neither a hands-free option nor a voice controlled interface removes the safety problems associated with the use of mobile phones in a car.
This individual differences study examined the separability of three often postulated executive functions-mental set shifting ("Shifting"), information updating and monitoring ("Updating"), and inhibition of prepotent responses ("Inhibition")-and their roles in complex "frontal lobe" or "executive" tasks. One hundred thirty-seven college students performed a set of relatively simple experimental tasks that are considered to predominantly tap each target executive function as well as a set of frequently used executive tasks: the Wisconsin Card Sorting Test (WCST), Tower of Hanoi (TOH), random number generation (RNG), operation span, and dual tasking. Confirmatory factor analysis indicated that the three target executive functions are moderately correlated with one another, but are clearly separable. Moreover, structural equation modeling suggested that the three functions contribute differentially to performance on complex executive tasks. Specifically, WCST performance was related most strongly to Shifting, TOH to Inhibition, RNG to Inhibition and Updating, and operation span to Updating. Dual task performance was not related to any of the three target functions. These results suggest that it is important to recognize both the unity and diversity of executive functions and that latent variable analysis is a useful approach to studying the organization and roles of executive functions.