David L Strayer

• University of Utah

Driving is a complex multisensory experience that requires the integration of various sensory inputs to maintain effective situational awareness, with vision and visual attention being paramount for safe driving. However, multitasking significantly degrades a driver's situational awareness and causes them to overlook or misjudge important aspects o...

Behavioral studies suggest that immersion in nature improves affect and executive attention. However, the neural mechanisms underlying these benefits remain unclear. This randomized controlled trial (N = 92) explored differences in self-reported affect and in frontal midline theta (FMθ), a neural oscillation linked to executive attention, between a...

The reliability of cognitive demand measures in controlled laboratory settings is well-documented; however, limited research has directly established their stability under real-life and high-stakes conditions, such as operating automated technology on actual highways. Partially automated vehicles have advanced to become an everyday mode of transpor...

Immersion in nature is thought to benefit mental health and cognitive performance; however, the underlying neural mechanisms of these benefits are unknown. In this randomized controlled trial, 92 participants were assigned to either a 40-min walk in nature at Red Butte Garden or in an urban environment on the University of Utah's medical campus. We...

Objective To examine the impact of secondary task performance on contextual blindness arising from the suppression and masking of temporal and spatial sequence learning. Background Dual-task scenarios can lead to a diminished ability to use environmental cues to guide attention, a phenomenon that is related to multitasking-induced inattentional bl...

There is conjecture that our modern urban environments place high demand on our attentional resources, which can become depleted over time and cause mental fatigue. Natural environments, on the other hand, are thought to provide relief from this demand and allow our resources to be replenished. While these claims have been assessed with self-report...

Vehicle automation is becoming more prevalent. Understanding how drivers use this technology and its safety implications is crucial. In a 6–8 week naturalistic study, we leveraged a hybrid naturalistic driving research design to evaluate driver behavior with Level 2 vehicle automation, incorporating unique naturalistic and experimental control cond...

Research suggests that spending time in nature is associated with numerous human behavioral health benefits, including improved executive functioning abilities, enhanced recovery from stressful situations, better mental health, and better educational outcomes. Greener neighborhoods also tend to have positive population-level health outcomes. Althou...

Objective This on-road study employed behavioral and neurophysiological measurement techniques to assess the influence of six weeks of practice driving a Level 2 partially automated vehicle on driver workload and engagement. Background Level 2 partial automation requires a driver to maintain supervisory control of the vehicle to detect “edge cases...

This on-road study employed behavioral and neurophysiological measurement techniques to assess the influence of six weeks of practice driving a Level 2 partially automated vehicle on driver workload and engagement. Level 2 partial automation requires a driver to maintain supervisory control of the vehicle to detect “edge cases” that the automation...

Exposure to nature is thought to enhance human attention. For decades, researchers across fields-from medical science to architecture to environmental psychology-have demonstrated this on a self-report and behavioral level. The presented work explores whether exposure to nature influences attention-related brain activity by using sophisticated cogn...

Objective: This study uses a detection task to measure changes in driver vigilance when operating four different partially automated systems. Background: Research show temporal declines in detection task performance during manual and fully automated driving, but the accuracy of using this approach for measuring changes in driver vigilance during...

Both anxiety and working memory capacity appear to predict increased (more negative) error‐related negativity (ERN) amplitudes, despite being inversely related to one another. Until the interactive effects of these variables on the ERN are clarified, there may be challenges posed to our ability to use the ERN as an endophenotype for anxiety, as som...

Introduction Research suggests that spending time in natural environments is associated with cognitive and affective benefits, while increased use of technology and time spent in urban environments are associated with depletion of cognitive resources and an increasing prevalence of mental illness. Attention Restoration Theory suggests that exposure...

Providing user-focused, objective, and quantified metrics for prosthesis usability may help reduce the high (up to 50%) abandonment rates and accelerate the clinical adoption and cost reimbursement for new and improved prosthetic systems. We comparatively evaluated several physiological, behavioral, and subjective cognitive workload measures applie...

Tillman et al. (2017) used evidence-accumulation modeling to ascertain the effects of a conversation (either with a passenger or on a hands-free cell phone) on a drivers' mental workload. They found that a concurrent conversation increased the response threshold but did not alter the rate of evidence accumulation. However, this earlier research col...

Prior studies of automated driving have focused on drivers’ evaluations of advanced driving assistance systems and their knowledge of the technology. An on-road experiment with novice drivers who had never used automated systems was conducted to examine the effects of the automation on the driving experience. Participants drove a Tesla Model 3 seda...

Tillman et al. (2017) used evidence-accumulation modeling to ascertain the effects of a conversation (either with a passenger or on a hands-free cell phone) on a drivers’ mental workload. They found that a concurrent conversation increased the response threshold but did not alter the rate of evidence accumulation. However, this earlier research col...

We examined the hidden costs of intermittent multitasking. Participants performed a pursuit-tracking task (Experiment 1) or drove in a high-fidelity driving simulator (Experiment 2) by itself or while concurrently performing an easy or difficult backwards counting task that periodically started and stopped, creating on-task and off-task multitaskin...

The effects of distraction on responses manifest in three ways: prolonged reaction times, and increased error and response omission rates. However, the latter effect is often ignored or assumed to be due to a separate cognitive process. We investigated omissions occurring in two paradigms that manipulated distraction. One required simple stimulus d...

Human operators often experience large fluctuations in cognitive workload over seconds timescales that can lead to sub-optimal performance, ranging from overload to neglect. Adaptive automation could potentially address this issue, but to do so it needs to be aware of real-time changes in operators’ spare cognitive capacity, so it can provide help...

This poster presents research exploring a driver's cognitive state during automated driving.

Objective: This research explores the effect of partial vehicle automation on neural indices of mental workload and visual engagement during on-road driving. Background: There is concern that the introduction of automated technology in vehicles may lead to low driver stimulation and subsequent disengagement from the driving environment. Simulator-b...

Introduction Partial driving automation is not always reliable and requires that drivers maintain readiness to take over control and manually operate the vehicle. Little is known about differences in drivers’ arousal and cognitive demands under partial automation and how it may make it difficult for drivers to transition from automated to manual mo...

Human operators often experience large fluctuations in cognitive workload over seconds time scales that can lead to sub-optimal performance, ranging from overload to neglect. Adaptive automation could potentially address this issue, but to do so it needs to be aware of real-time changes in operators’ spare cognitive capacity, so it can provide help...

There is abundant evidence for both cognitive and affective improvements stemming from spending time in nature; however, the mechanism underlying these effects are still under debate. Frameworks such as Attention Restoration Theory (ART; Kaplan 1995) and Stress Recovery Theory (SRT; Ulrich et al. 1991) have been helpful in understanding how restora...

Semi-automated vehicles (Level-2) provide driving assistance, but they still require driver supervision to maintain safe driving. However, little is known about potential differences in drivers’ cognitive states during manual vs. Level-2 automated driving. The current study systematically examined the effects of manual and Level-2 driving on driver...

Exposure to environments that contain natural features can benefit mood, cognition, and physiological responses. Previous research proposed exposure to nature restores voluntary attention-attention that is directed towards a task through top down control. Voluntary attention is limited in capacity and depletes with use. Nature provides unique stimu...

Stress Recovery Theory (SRT) suggests that time spent in nature reduces stress. While many studies have examined changes in stress physiology after exposure to nature imagery, nature virtual reality, or nature walks, this study is the first to examine changes in heart rate (HR) and vagally mediated HR variability, as assessed by Respiratory Sinus A...

As more active driving systems are integrated into vehicles, the role and responsibilities of drivers using these technologies will change fundamentally from conventional vehicles. Vehicle automation now offers extended control of vehicle's speed, headway and lane position, but calling upon drivers to continuously monitor the road and traffic envir...

We examined the hidden costs of intermittent multitasking. Participants performed a pursuit-tracking task (Experiment 1) or drove in a high-fidelity driving simulator (Experiment 2) by itself or while concurrently performing an easy or difficult backwards counting task that periodically started and stopped, creating on-task and off-task multitaskin...

In-vehicle information systems (IVIS) refer to a collection of features in vehicles that allow motorists to complete tasks (often unrelated to driving) while operating the vehicle. These systems may interfere, to a greater extent, with older drivers’ ability to attend to the visual and cognitive demands of the driving environment. The current study...

According to Kaplan's Theory of Attention Restoration (ART), spending time in a natural environment can restore depleted cognitive resources. If this is true, then nature exposure may modulate the error-related negativity (ERN), a component of the event-related brain potential (ERP) that is related to cognitive control and attentional allocation. A...

Background: New automobiles provide a variety of features that allow motorists to perform a plethora of secondary tasks unrelated to the primary task of driving. Despite their ubiquity, surprisingly little is known about how these complex multimodal in-vehicle information systems (IVIS) interactions impact a driver's workload. Results: The curre...

Many challenges associated with aging faced by older drivers may be attenuated by advancements of in-vehicle technologies. One class in particular, In Vehicle Information Systems (IVIS), refers to a collection of features and functions that allow motorists to complete tasks in addition to operating the vehicle. Little is known about how interaction...

Human operators often experience large fluctuations in cognitive workload that can lead to sub-optimal performance, ranging from overload to neglect. Help from automated support systems could potentially address this issue, but to do so the system would ideally need to be aware of real-time changes in operators’ cognitive workload, so it can provid...

This article examines the causes of dual-task interference in a time pressured dynamic environment. Resource sharing theories are often used as a theoretical framework to understand dual-task interference. These frameworks propose that resources from a limited pool of information-processing capacity are reallocated toward the primary task as task l...

This paper examines the causes of dual-task interference in a time pressured dynamic environment. Resource sharing theories are often used as a theoretical framework to understand dual-task interference. These frameworks propose that resources from a limited pool of information-processing capacity is reallocated towards the primary task as task loa...

Motorists often engage in secondary tasks unrelated to driving that increase cognitive workload, resulting in fatal crashes and injuries. An International Standards Organization method for measuring a driver’s cognitive workload, the detection response task (DRT), correlates well with driving outcomes, but investigation of its putative theoretical...

Objective: The present research compared and contrasted the workload associated with using in-vehicle information systems commonly available in five different automotive original equipment manufacturers (OEMs) with that of CarPlay and Android Auto when used in the same vehicles. Background: A growing trend is to provide access to portable smartp...

Given the promise for auditory-vocal systems to be less distracting and safer to use than their visual-manual counterparts, automotive manufacturers are introducing an increasing number of voice assistant-like interfaces in vehicles. However, recent studies suggest using auditory-vocal systems can be mentally taxing for drivers, and require long in...

As driving functions become increasingly automated, motorists run the risk of becoming cognitively removed from the driving process. Psychophysiological measures may provide added value not captured through behavioral or self-report measures alone. This paper provides a selective review of the psychophysiological measures that can be utilized to as...

People around the world endanger the lives of themselves and others every day by dividing their attention across multiple tasks, such as driving and talking on a cell phone. These dangers result from splitting and overtaxing our limited voluntary attentional efforts. Current tools for measuring attentional effort, also known as cognitive workload,...

The N-back and Surrogate Reference Task (SuRT) are frequently used to evaluate the workload potential of secondary driving tasks as high cognitive and visual demand benchmarks. This paper examines the effect of repeated exposures to the N-back and SuRT reference tasks, and any resulting change in task performance or workload that may negate their e...

The ISO 17488 standard Detection Response Task (DRT) has been validated as an effective tool for measuring fluctuations in cognitive workload while driving and performing secondary tasks. This research evaluated the possibility of consolidating a dual stimulus DRT to a single remote LED stimulus to concurrently measure visual and cognitive demand....

The introduction of semi-automated driving systems is expected to mitigate the safety consequences of human error. Observational findings suggest that relinquishing control of vehicle operational control to assistance systems might diminish driver engagement in the driving task, by reducing levels of arousal. In this study, drivers drove a Tesla Mo...

The Detection Response Task (DRT) is an international standard for assessing workload that has minimal effects on primary task performance, making it an attractive option for workload measurement in many settings. An increase in DRT response times and a decrease hit rates as primary task load increases is thought to occur due to competing resources...

Despite driver assistance systems being engineered to enhance safety, recent studies show the potential for some of these systems and deficient human–machine interfaces to cause unintended consequences on safety. The NHTSA, the Alliance of Automotive Manufacturers, and the European Commission have all released best practices and human factors guide...

Suicide, self-injury, and predisposing vulnerabilities aggregate in families. Those at greatest risk often show deficits in two biologically-mediated domains: behavioral control and emotion regulation. This pilot study explored electroencephalographic and cardiovascular indices of self-regulation among typical and suicidal adolescents (n = 30/group...

Despite driver assistance systems being engineered to enhance safety, recent studies show the potential for some of these systems and deficient human-machine interfaces to cause unintended consequences on safety. NHTSA, the Alliance of Automotive Manufacturers and the European Commission have all released best practices and Human Factors guidelines...

A study was conducted to examine the cognitive underpinnings of consumers’ beliefs and confidence in their beliefs about fully automated vehicles. Opinions about self-driving cars tended to be favorable. The most negative views were held by participants who had the least knowledge of fully automated vehicles. Low trust in technology was also associ...

Previous research shows that exposure to natural environments can decrease stress and improve performance on tasks measuring attention. We used electroencephalography (EEG) to measure changes in neural activity before, during, and after prolonged exposure to nature. We found midline frontal theta (4-8hz) activity significantly decreased after expos...

Motorists often engage in secondary tasks unrelated to driving that increase cognitive workload, resulting in fatal crashes and injuries. An International Standards Organization (ISO) method for measuring a driver’s cognitive workload, the Detection Response Task (DRT), correlates well with driving outcomes, but investigation of its putative theore...

American youth spend more time with media than any other waking activity: an average of 7.5 hours per day, every day. On average, 29% of that time is spent juggling multiple media streams simultaneously (ie, media multitasking). This phenomenon is not limited to American youth but is paralleled across the globe. Given that a large number of media m...

The increased availability of "small screens," wireless devices with Internet-enabled connections, and their associated applications has almost overnight changed the way that we interact with our phones. The current work outlines some of the aspects of this problem as it relates to the influence of small screens on driving safety. Small screens are...

The goal of this research was to examine the impact of voice-based interactions using 3 different intelligent personal assistants (Apple’s Siri, Google’s Google Now for Android phones, and Microsoft’s Cortana) on the cognitive workload of the driver. In 2 experiments using an instrumented vehicle on suburban roadways, we measured the cognitive work...

Partial-autonomous vehicles are among us and represent a prominent testing ground for assessing the human interaction with autonomous vehicles. One main limitation of the studies investigating would-be users’ attitude toward partial to full autonomous driving stems from their indirect experience with such technology. In this study, participants dro...

Cognitive load from secondary tasks is a source of distraction causing injuries and fatalities on the roadway. The Detection Response Task (DRT) is an international standard for assessing cognitive load on drivers’ attention that can be performed as a secondary task with little to no measurable effect on the primary driving task. We investigated wh...

Preliminary work on comparing the ISO DRT to a modified Choice Response Task in its ability to detect workload for a visual search task.

The present study investigated individual differences in information processing following errant behavior. Participants were initially classified as high or as low working memory capacity using the Operation Span Task. In a subsequent session, they then performed a high congruency version of the flanker task under both speed and accuracy stress. We...

With semi-autonomous vehicles being pushed onto the market, driver monitoring systems play a relevant role in determining the user’s level of engagement whenever an automated-to-manual transition of control is scheduled to occur. As current monitoring systems heavily rely on steering behavior and ocular parameters as inputs for their algorithms, th...

With semi-autonomous vehicles being pushed onto the market, driver monitoring systems play a relevant role in determining the user’s fitness to drive whenever an automated-to-manual transition of control occurs. Current monitoring systems heavily rely on steering behavior and ocular parameters as inputs to determine the driver state. This study aim...

This research examined the impact of in-vehicle information system (IVIS) interactions on the driver’s cognitive workload; 257 subjects participated in a weeklong evaluation of the IVIS interaction in one of ten different model-year 2015 automobiles. After an initial assessment of the cognitive workload associated with using the IVIS, participants...

Objective: The cognitive workload of three Smartphone Digital Assistants (SDA) was manipulated in an on-off manner while participants drove an instrumented vehicle in order to measure the costs associated with intermittent dual tasking. Background: Previous research has shown costs in productivity when switching between two discrete tasks; however,...

Objective: A set of 4 driving related tasks were used to evaluate the potential for a modified Detection Response Task (DRT) to simultaneously measure visual and cognitive task demands. Background: The accurate assessment of cognitive and visual tasks demands in driving has become increasingly important. As of yet, no simple, cost effective approac...

This panel addresses current efforts associated with the evaluation of demands associated with the use of voice-based in-vehicle interfaces. As generally implemented, these systems are perhaps best characterized as mixed-mode interfaces drawing upon varying levels of auditory, vocal, visual, manual and cognitive resources. Numerous efforts have qua...

The current research sought to understand the sources of cognitive distraction stemming from voice-based in-vehicle infotainment systems (IVIS) to send and receive textual information. Three experiments each evaluated 1) a baseline single-task condition, 2) listening to e-mail/text messages read by a “natural” pre-recorded human voice, 3) listening...

With the emergence of vehicle-based technologies that could compete for attention due to visual and cognitive workloads in a driving environment, it is important to accurately assess the various components of potential distractions. Current Detection Response Task (DRT) measurements are sensitive to overall mental workload, but may not be useful fo...

Drivers claim to use cell phones for benefits such as getting work done and to increase productivity (Sanbonmatsu, Strayer, Behrends, Medeiros-Ward, & Watson, in press). However, individuals who use cell phones while driving may be more likely to rely on reconstructive processes in memory due to divided attention, making them more susceptible to er...

The use of cell phones while driving is ubiquitous, particularly in countries where the practice is legal. However, surveys indicate that most drivers favor legislation to limit the use of mobile devices during the operation of a vehicle. A study was conducted to understand this inconsistency between what drivers do and what they advocate for other...

This study investigated whether multimodal redundant warnings presented by advanced assistance systems reduce brake response times. Warnings presented by assistance systems are designed to assist drivers by informing them that evasive driving maneuvers are needed in order to avoid a potential accident. If these warnings are poorly designed, they ma...