Performance, Hemodynamics, and Stress in a Two-Day Vigilance Task: Practical and Theoretical Implications.

OBJECTIVE: To explore vigilance task performance, cerebral blood flow velocity (CBFV), workload, and stress in a within-subjects, two-session experiment. BACKGROUND: Vigilance, or sustained attention, tasks are often characterized by a decline in operator performance and CBFV with time on task, and high workload and stress. Though performance is known to improve with practice, past research has not included measures of CBFV, stress, and workload in a within-subjects multi-session design, which may also provide insight into ongoing theoretical debate. METHOD: Participants performed a vigilance task on two separate occasions. Performance, CBFV, workload, and self-reported stress were measured. RESULTS: Within each session, results were consistent with the vigilance profile found in prior research. Across sessions, performance improved but the time on task decrement remained. Mean CBFV and workload ratings did not differ between sessions, but participants reported significantly less distress, worry, and engagement after session two compared to one. CONCLUSION: Though practice may not disrupt the standard vigilance profile, it may serve to improve overall performance and reduce stress. However, repeated exposure may have negative implications for engagement and mind-wandering. APPLICATION: It is important to better understand the relationship between experience, performance, physiological response, and self-reported stress and workload in vigilance because real-world environments often require operators to do the same task over many occasions. While performance improvement and reduced distress is an encouraging result, the decline in engagement requires further research. Results across sessions fail to provide support to the mind-wandering theory of vigilance.

This Is Your Brain on Autopilot 2.0: The Influence of Practice on Driver Workload and Engagement During On-Road, Partially Automated Driving.

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" that the automation is not equipped to handle. There is mixed evidence regarding whether drivers can do so effectively. There is also an open question regarding how practice and familiarity with automation influence driver cognitive states over time. METHOD: Behavioral and neurophysiological measures of driver workload and visual engagement were recorded from 30 participants at two testing sessions-with a six-week familiarization period in-between. At both testing sessions, participants drove a vehicle with partial automation engaged (Level 2) and not engaged (Level 0) on two interstate highways while reaction times to the detection response task (DRT) and neurophysiological (EEG) metrics of frontal theta and parietal alpha were recorded. RESULTS: DRT results demonstrated that partially automated driving placed more cognitive load on drivers than manual driving and six weeks of practice decreased driver workload-though only when the driving environment was relatively simple. EEG metrics of frontal theta and parietal alpha showed null effects of partial automation. CONCLUSION: Driver workload was influenced by level of automation, specific highway characteristics, and by practice over time, but only on a behavioral level and not on a neural level. APPLICATION: These findings expand our understanding of the influence of practice on driver cognitive states under Level 2 partial automation.

Rendezvous Under Temporal Uncertainty.

OBJECTIVE: Three experiments sought to understand performance limitations in controlling a ship attempting to meet another moving ship that approached from various trajectories. The influence of uncertainty, resulting from occasional unpredictable delays in one's own movement, was examined. BACKGROUND: Cognitive elements of rendezvous have been little studied. Related work such as the planning fallacy and bias toward underestimating time-to-contact imply a tendency toward late arrival at a rendezvous. METHODS: In a simplified simulation, participants controlled the speed and/or heading of their own ship once per scenario to try to rendezvous with another ship. Forty-five scenarios of approximately 30 s were conducted with different starting geometries and, in two of three experiments, with different frequencies and lengths of the unexpected delays. RESULTS: Perfect rendezvous were hard to obtain, with a general tendency to arrive late and pass behind the target vessel, although this was dependent on the angle of approach and relative speed. When occasional delays were introduced, less frequent but longer delays disrupted performance more than shorter but more frequent delays. Where delays were possible, but no delay occurred, there was no longer evidence of a general tendency to more frequently pass behind the target ship. Additionally, people did not wait to see if the unpredictable delays would occur before executing a course of action. Different control strategies were deployed and dual axis control was preferred. CONCLUSIONS: The tendency to arrive late and the influence of the possibility of uncertain delays are discussed in relationship to control strategies.

Detection of Hostile Intent by Spatial Movements.

OBJECTIVE: The ability of people to infer intentions from movement of other vessels was investigated. Across three levels of variability in movements in the path of computer-controlled ships, participants attempted to determine which entity was hostile. BACKGROUND: Detection of hostile intentions through spatial movements of vessels is important in an array of real-world scenarios. This experiment sought to determine baseline abilities of humans to do so. METHODS: Participants selected a discrete movement direction of their ship. Six other ships' locations then updated. A single entity displayed one of two hostile behaviors: shadowing, which involved mirroring the participant's vessel's movements; and hunting, which involved closing in on the participant's vessel. Trials allowed up to 35 moves before identifying the hostile ship and its behavior. Uncertainty was introduced through adding variability to ships' movements such that their path was 0%, 25%, or 50% random. RESULTS: Even with no variability in the ships' movements, accurate detection was low, identifying the hostile entity about 60% of the time. Variability in the paths decreased detection. Detection of hunting was strongly degraded by distance between ownship and the hostile ship, but shadowing was not. Strategies employing different directions of movement across the trial, but also featuring some runs of consecutive movements, facilitated detection. CONCLUSIONS: Early identification of threats based on movement characteristics alone is likely to be difficult, but particularly so when adversaries employ some level of uncertainty to mask their intentions. These findings highlight the need to develop decision aids to support human performance.

This Is Your Brain on Autopilot: Neural Indices of Driver Workload and Engagement During Partial Vehicle Automation.

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-based studies have examined the effect of automation on a driver's cognitive state, but it is unknown how the conclusions translate to on-road driving. Electroencephalographic (EEG) measures of frontal theta and parietal alpha can provide insight into a driver's mental workload and visual engagement while driving under various conditions. METHOD: EEG was recorded from 71 participants while driving on the roadway. We examined two age cohorts, on two different highway configurations, in four different vehicles, with partial vehicle automation both engaged and disengaged. RESULTS: Analysis of frontal theta and parietal alpha power revealed that there was no change in mental workload or visual engagement when driving manually compared with driving under partial vehicle automation. CONCLUSION: Drivers new to the technology remained engaged with the driving environment when operating under partial vehicle automation. These findings suggest that the concern surrounding driver disengagement under vehicle automation may need to be tempered, at least for drivers new to the experience. APPLICATION: These findings expand our understanding of the effects of partial vehicle automation on drivers' cognitive states.

Expectancy or Salience?-Replicating Senders' Dial-Monitoring Experiments With a Gaze-Contingent Window.

INTRODUCTION: In the 1950s and 1960s, John Senders carried out a number of influential experiments on the monitoring of multidegree-of-freedom systems. In these experiments, participants were tasked with detecting events (threshold crossings) for multiple dials, each presenting a signal with different bandwidth. Senders' analyses showed a nearly linear relationship between signal bandwidth and the amount of attention paid to the dial, and he argued that humans sample according to bandwidth, in line with the Nyquist-Shannon sampling theorem. OBJECTIVE: The current study tested whether humans indeed sample the dials based on bandwidth alone or whether they also use salient peripheral cues. METHODS: A dial-monitoring task was performed by 33 participants. In half of the trials, a gaze-contingent window was used that blocked peripheral vision. RESULTS: The results showed that, without peripheral vision, humans do not effectively distribute their attention across the dials. The findings also suggest that, when given full view, humans can detect the speed of the dial using their peripheral vision. CONCLUSION: It is concluded that salience and bandwidth are both drivers of distributed visual attention in a dial-monitoring task. APPLICATION: The present findings indicate that salience plays a major role in guiding human attention. A subsequent recommendation for future human-machine interface design is that task-critical elements should be made salient.

Information Access Effort: The Role of Head Movements for Information Presented at Increasing Eccentricity on Flat Panel and Head-Mounted Displays.

OBJECTIVE: This experiment examined performance costs when processing two sources of information positioned at increasing distances using a flat panel display and an augmented reality head-mounted display (AR-HMD). BACKGROUND: The AR-HMD enables positioning virtual information at various distances in space. However, the proximity compatibility principle suggests that closer separation when two sources of information require mental integration assists performance, whereas increased separation between two sources hurts integration performance more than when a single source requires focused attention. Previous studies have provided inconsistent findings regarding costs associated with increased separation. Few of these experiments have examined separation for both focused and integration tasks, compared vertical and lateral separation, or measured head movements. METHOD: Three experiments collectively examined these issues using a flat panel display and a virtual display presented with an HMD, where the separation of information varied laterally or vertically during a focused attention (digit reading) task and an information integration (mental subtraction) task. RESULTS: There was no performance cost for either display when information was increasingly separated. However, head movements mitigated performance costs by preserving accuracy at larger separations without increasing response time. CONCLUSION: Head movements appear to mitigate performance costs associated with presenting information increasingly far apart on flat panel displays and HMDs. Both eye scanning and head movements appear to be less effortful than expected. APPLICATION: These findings have important implications for design guidelines regarding the placement of information presented on flat panel displays and, more specifically, HMDs, which can present information 360° around the user.

Minding the Gap: Effects of an Attention Maintenance Training Program on Driver Calibration.

OBJECTIVE: The present study examines the effect of an existing driver training program, FOrward Concentration and Attention Learning (FOCAL) on young drivers' calibration, drivers' ability to estimate the length of their in-vehicle glances while driving, using two different measures, normalized difference scores and Brier Scores. BACKGROUND: Young drivers are poor at maintaining attention to the forward roadway while driving a vehicle. Additionally, drivers may overestimate their attention maintenance abilities. Driver training programs such as FOCAL may train target skills such as attention maintenance but also might serve as a promising way to reduce errors in drivers' calibration of their self-perceived attention maintenance behaviors in comparison to their actual performance. METHOD: Thirty-six participants completed either FOCAL or a Placebo training program, immediately followed by driving simulator evaluations of their attention maintenance performance. In the evaluation drive, participants navigated four driving simulator scenarios during which their eyes were tracked. In each scenario, participants performed a map task on a tablet simulating an in-vehicle infotainment system. RESULTS: FOCAL-trained drivers maintained their attention to the forward roadway more and reported better calibration using the normalized difference measure than Placebo-trained drivers. However, the Brier scores did not distinguish the two groups on their calibration. CONCLUSION: The study implies that FOCAL has the potential to improve not only attention maintenance skills but also calibration of the skills for young drivers. APPLICATION: Driver training programs may be designed to train not only targeted higher cognitive skills but also driver calibration-both critical for driving safety in young drivers.

What's that on Your Phone? Effects of Mobile Device Task Type on Pedestrian Performance.

BACKGROUND: The number of accidents due to distracted pedestrian is on the rise and many governments and institutions are enacting public policies which restrict texting while walking. However, pedestrians do more than just texting when they use their mobile devices on the go. OBJECTIVE: Exploring pedestrian multitasking, this paper aims to examine the effects of mobile device task type on pedestrian performance outcomes. METHOD: We performed two studies in lab simulations where 78 participants were asked to perform different tasks on a mobile device (playing a game, reading, writing an email, texting one person, group texting) while performing a pedestrian visual discrimination task while either standing or walking on a treadmill. Behavioral performance as well as neurophysiological data are collected. RESULTS: Results show that compared to a no-phone control, multitasking with any of the tasks on a mobile device leads to poor performance on a pedestrian visual discrimination task. Playing a game is the most cognitively demanding task and leads to the greatest performance degradation. CONCLUSION: Our studies show that multitasking with a mobile device has the potential to negatively impact pedestrian safety, regardless of task type. However, the impacts of different mobile device tasks are not all equivalent. More research is needed to tease out the different effects of these various tasks and to design mobile applications which effectively and safely capture pedestrians' attention. APPLICATION: Public policy, infrastructure, and smart technologies can be used to mitigate the negative effects of mobile multitasking. A more thorough understanding of mobile device task-specific factors at play can help tailor these counter-measures to better aid distracted pedestrians.

Detecting and Responding to Information Overload With an Adaptive User Interface.

OBJECTIVE: The objective of this study was to develop and evaluate an adaptive user interface that could detect states of operator information overload and calibrate the amount of information on the screen. BACKGROUND: Machine learning can detect changes in operating context and trigger adaptive user interfaces (AUIs) to accommodate those changes. Operator attentional state represents a promising aspect of operating context for triggering AUIs. Behavioral rather than physiological indices can be used to infer operator attentional state. METHOD: In Experiment 1, a network analysis task sought to induce states of information overload relative to a baseline. Streams of interaction data were taken from these two states and used to train machine learning classifiers. We implemented these classifiers in Experiment 2 to drive an AUI that automatically calibrated the amount of information displayed to operators. RESULTS: Experiment 1 successfully induced information overload in participants, resulting in lower accuracy, slower completion time, and higher workload. A series of machine learning classifiers detected states of information overload significantly above chance level. Experiment 2 identified four clusters of users who responded significantly differently to the AUIs. The AUIs benefited performance, completion time, and workload in three clusters. CONCLUSION: Behavioral indices can successfully detect states of information overload and be used to effectively drive an AUI for some user groups. The success of AUIs may be contingent on characteristics of the user group. APPLICATION: This research applies to domains seeking real-time assessments of user attentional or psychological state.

The Effect of Lane Direction Pavement Markings on Driving Performance and Safety: A Driving Simulator Study.

OBJECTIVE: A driving simulator study was conducted to test the effect of directions pavement markings (DPMs) on drivers' performance. BACKGROUND: The perception of traditional direction signs may be less efficient than that of DPMs because drivers allocate more attentional resources to the road than to any other location. METHOD: Two experimental conditions of DPMs were tested: (a) the name of the lane's destination town, inscribed in white letters; (b) red and white shields enclosing the name of the lane's destination town. In both conditions, the name or shield was preceded by a white arrow and traditional road signs were presented as well. The experimental conditions were compared to a baseline condition, which consisted of traditional road signs only. Various scenarios of three-lane highways were simulated and the number of vehicles on the road was manipulated, forming a 2 × 3 design (two load conditions × three experimental conditions). Twenty-two participants took part in the experiment. RESULTS: Pavement markings in both configurations were highly beneficial. Compared with the baseline condition, in both experimental conditions, the drivers noticed the correct lane sooner and moved to the correct lane earlier. Results also suggested that white markings are more beneficial than shield markings; however, this finding should be further confirmed. CONCLUSION: Lane DPMS are desirable as they are likely to improve traffic safety at relatively low cost. APPLICATION: Regulations demanding the presence of DPMs, at the very least in low visibility decision sites, would increase traffic safety.

Attention to Changes on a Head-Worn Display: Two Preclinical Studies with Healthcare Scenarios.

OBJECTIVE: In two experiments, we examined how quickly different visual alerts on a head-worn display (HWD) would capture participants' attention to a matrix of patient vital sign values, while multitasking. BACKGROUND: An HWD could help clinicians monitor multiple patients, regardless of where the clinician is located. We sought effective ways for HWDs to alert multitasking wearers to important events. METHODS: In two preclinical experiments, university student participants performed a visuomotor tracking task while simultaneously monitoring simulated patient vital signs on an HWD to detect abnormal values. Methods to attract attention to abnormal values included highlighting abnormal vital signs and imposing a white flash over the entire display. RESULTS: Experiment 1 found that participants detected abnormal values faster with high contrast than low contrast greyscale highlights, even while performing difficult tracking. In Experiment 2, a white flash of the entire screen quickly and reliably captured attention to vital signs, but less so on an HWD than on a conventional screen. CONCLUSION: Visual alerts on HWDs can direct users' attention to patient transition events (PTEs) even under high visual-perceptual load, but not as quickly as visual alerts on fixed displays. Aspects of the results have since been tested in a healthcare context. APPLICATION: Potential applications include informing the design of HWD interfaces for monitoring multiple processes and informing future research on capturing attention to HWDs.

Recognizing children's emotions in child abuse and neglect.

Past research has suggested that parents' ability to recognize their children's emotions is associated with an enhanced quality of parent-child interactions and appropriateness of parental caregiving behavior. Although this association has also been examined in abusive and neglectful parents, the results are mixed and do not adequately address child neglect. Based on the Social Information Processing model of child abuse and neglect, we examined the association between mothers' ability to recognize children's emotions and self- and professionals-reported child abuse and neglect. The ability to recognize children's emotions was assessed with an implicit valence classification task and an emotion labeling task. A convenience sample of 166 mothers (78 with at least one child referred to Child Protection Services) completed the tasks. Child abuse and neglect were measured with self-report and professionals-report instruments. The moderating role of mothers' intellectual functioning and socioeconomic status were also examined. Results revealed that abusive mothers performed more poorly on the negative emotions recognition task, while neglectful mothers demonstrated a lower overall ability in recognizing children's emotions. When classifying the valence of emotions, mothers who obtained higher scores on child neglect presented a higher positivity bias particularly when their scores in measures of intellectual functioning were low. There was no moderation effect for socioeconomic status. Moreover, the results for child abuse were mainly observed with self-report measures, while for child neglect, they predominantly emerged with professionals-report. Our findings highlight the important contribution of the social information processing model in the context of child maltreatment, with implications for prevention and intervention addressed.

Drivers' Spatio-Temporal Attentional Distributions Are Influenced by Vehicle Dynamics and Displayed Point of View.

OBJECTIVE: The aim of this study is to measure drivers' attention to preview and their velocity and acceleration tracking error to evaluate two- and three-dimensional displays for following a winding roadway. BACKGROUND: Display perturbation techniques and Fourier analysis of steering movements can be used to infer drivers' spatio-temporal distribution of attention to preview. Fourier analysis of tracking error time histories provides measures of position, velocity, and acceleration error. METHOD: Participants tracked a winding roadway with 1 s of preview in low-fidelity driving simulations. Position and rate-aided vehicle dynamics were paired with top-down and windshield displays of the roadway. RESULTS: For both vehicle dynamics, tracking was smoother with the windshield display. This display emphasizes nearer preview positions and has a closer correspondence to the control-theoretic optimal attentional distributions for these tasks than the top-down display. This correspondence is interpreted as a form of stimulus-response compatibility. The position error and attentional signal-to-noise ratios did not differ between the two displays with position control, but with more complex rate-aided control much higher position error and much lower attentional signal-to-noise ratios occurred with the top-down display. CONCLUSION: Display-driven influences on the distribution of attention may facilitate tracking with preview when they are similar to optimal attentional distributions derived from control theory. APPLICATION: Display perturbation techniques can be used to assess spatially distributed attention to evaluate displays and secondary tasks in the context of driving. This methodology can supplement eye movement measurements to determine what information is guiding drivers' actions.

Shared Gaze Fails to Improve Team Visual Monitoring.

OBJECTIVE: The aim was to test the value of shared gaze as a way to improve team performance in a visual monitoring task. BACKGROUND: Teams outperform individuals in monitoring tasks, but fall short of achievable levels. Shared-gaze displays offer a potential method of improving team efficiency. Within a shared-gaze arrangement, operators collaborate on a visual task, and each team member's display includes a cursor to represent the other teammates' point of regard. Past work has suggested that shared gaze allows operators to better communicate and coordinate their attentional scanning in a visual search task. The current experiments sought to replicate and extend earlier findings of inefficient team performance in a visual monitoring task, and asked whether shared gaze would improve team efficiency. METHOD: Participants performed a visual monitoring task framed as a sonar operation. Displays were matrices of luminance patches varying in intensity. The participants' task was to monitor for occasional critical signals, patches of high luminance. In Experiment 1, pairs of participants performed the task independently, or working as teams. In Experiment 2, teams of two participants performed the task with or without shared-gaze displays. RESULTS: In Experiment 1, teams detected more critical signals than individuals, but were statistically inefficient; detection rates were lower than predicted by a control model that assumed pairs of operators searching in isolation. In Experiment 2, shared gaze failed to increase target detection rates. CONCLUSION AND APPLICATION: Operators collaborate inefficiently in visual monitoring tasks, and shared gaze does not improve their performance.

Restoring Attentional Resources With Nature: A Replication Study of Berto's (2005) Paradigm Including Commentary From Dr. Rita Berto.

OBJECTIVE: The aim of this study is to replicate Berto's (2005) heavily cited work on attention restoration. BACKGROUND: Nature interventions have gained increased interest for improving performance of attentionally demanding tasks. Berto (2005) indicated that viewing digital nature images could improve performance on a subsequent response inhibition task, the sustained attention to response task (SART). However, experimental design and statistical concerns about her experiments as well as failure to support her findings across multiple unpublished studies in our laboratory provided rationale for this replication study. METHOD: Twenty participants were each assigned to one of three digital image conditions: nature, urban, and control. Participants performed the SART before and after digital image exposure. RESULTS: SART performance metrics (total correct target responses, mean response time, and transformed d') were analyzed using 2 (SART) × 3 (image interventions) mixed design ANOVAs. The results failed to replicate Berto (2005). CONCLUSION: Possible reasons for not replicating Berto (2005) are discussed, including (1) sample differences, (2) different testing environments and procedures, (3) insufficient attentional depletion, and (4) individual differences. APPLICATIONS: Research needs to determine the effectiveness of such interventions, the specific attention tasks that might benefit, and the individual difference variables relevant for attention restoration.

Drivers' Cue Utilization Predicts Cognitive Resource Consumption During a Simulated Driving Scenario.

OBJECTIVE: This study was designed to examine whether cue utilization differentiates drivers' consumption of cognitive resources during a simulated driving task. BACKGROUND: Outcomes from previous research have demonstrated that a general capacity for cue utilization differentiates cognitive load during novel process control tasks. However, it was previously unclear whether similar results would be demonstrated during familiar operational tasks. METHOD: Based on an assessment of cue utilization within a driving context, participants were classified into higher or lower cue utilization typologies. During a simulated driving task, cognitive load was assessed through changes against baseline in cerebral oxygenation in the prefrontal cortex, through eye behavior metrics (fixation rates and fixation dispersion), and through driving performance (frequency of missed traffic signals and speed exceedances). RESULTS: Drivers with higher cue utilization recorded smaller mean fixation dispersions, smaller increases in cerebral oxygenation, and fewer missed traffic signals compared with drivers with lower cue utilization. These results suggest that compared with drivers with lower cue utilization, drivers with higher cue utilization experienced lower cognitive load during the simulated driving task while maintaining a higher level of performance. CONCLUSION: The results provide support for the assertion that, among qualified operators, a greater capacity for cue utilization is associated with lower cognitive load during operational tasks. APPLICATION: Cue-based assessments of driving may be beneficial in predicting performance and assisting in targeted training for recently qualified and/or older drivers.

Artificial Optic Flow Guides Visual Attention in a Driving Scene.

OBJECTIVE: The objective of this study was to investigate whether an artificial optic flow created by dot motion guides attention in a driving scene. BACKGROUND: To achieve safe driving, it is essential to understand the characteristics of human visual information processing as well as to provide appropriate support for drivers. Past research has demonstrated that expanding optic flow guides visual attention to the focus of expansion. Optic flow is an attractive candidate for use as a cue to direct drivers' attention toward the significant information. The question addressed concerns whether an artificial optic flow can successfully guide attention even in a traffic situation involving the optic flow that naturally occurs while driving. METHOD: We developed a visual search paradigm embedded in a video of a driving scene. Participants first observed an optic flow motion pattern superimposed on the video for brief period; next, when the optic flow and video ceased, they searched a static display for a target among multiple distractors. RESULTS: The target detection was faster when a target's locus coincided with the implied focus of expansion from the preceding optic flow (vs. other loci). CONCLUSION: The artificial optic flow guides attention and facilitates searching objects at the focus of expansion even when the optic flow was superimposed on a driving scene. APPLICATION: Optic flow can be an effective cue for guiding drivers' attention in a traffic situation. This finding contributes to the understanding of visual attention in moving space and helps develop technology for traffic safety.

Classification of Attentional Tunneling Through Behavioral Indices.

OBJECTIVE: The objective of this study was to develop a machine learning classifier to infer attentional tunneling through behavioral indices. This research serves as a proof of concept for a method for inferring operator state to trigger adaptations to user interfaces. BACKGROUND: Adaptive user interfaces adapt their information content or configuration to changes in operating context. Operator attentional states represent a promising class of triggers for these adaptations. Behavioral indices may be a viable alternative to physiological correlates for triggering interface adaptations based on attentional state. METHOD: A visual search task sought to induce attentional tunneling in participants. We analyzed user interaction under tunnel and non-tunnel conditions to determine whether the paradigm was successful. We then examined the performance trade-offs stemming from attentional tunnels. Finally, we developed a machine learning classifier to identify patterns of interaction characteristics associated with attentional tunnels. RESULTS: The experimental paradigm successfully induced attentional tunnels. Attentional tunnels were shown to improve performance when information appeared within them, but to hinder performance when it appeared outside. Participants were found to be more tunneled in their second tunnel trial relative to their first. Our classifier achieved a classification accuracy similar to comparable studies (area under curve = 0.74). CONCLUSION: Behavioral indices can be used to infer attentional tunneling. There is a performance trade-off from attentional tunneling, suggesting the opportunity for adaptive systems. APPLICATION: This research applies to adaptive automation aimed at managing operator attention in information-dense work domains.

Knowing What's Coming: Unpredictable Motion Causes More Motion Sickness.

OBJECTIVE: This study explores the role of anticipation in motion sickness. We compared three conditions varying in motion predictability and assessed the effect of anticipation on subsequent illness ratings using a within-subjects design. BACKGROUND: Anticipation is thought to play a role in motion sickness by reducing the discrepancy between sensed and expected sensory information. However, both the exact role and potential magnitude of anticipation on motion sickness are unknown. METHOD: Participants (N = 17) were exposed to three 15-min conditions consisting of repeated fore-aft motion on a sled on a 40-m rail (1) at constant intervals and consistent motion direction, (2) at constant intervals but varied motion direction, and (3) at varied intervals but consistent motion direction. Conditions were otherwise identical in motion intensity and displacement, as they were composed of the same repetitions of identical blocks of motion. Illness ratings were recorded at 1-min intervals using an 11-point motion sickness scale. RESULTS: Average illness ratings after exposure were significantly lower for the predictable condition, compared with both the directionally unpredictable condition and the temporally unpredictable condition. CONCLUSION: Unpredictable motion is significantly more provocative compared with predictable motion. Findings suggest motion sickness results from a discrepancy between sensed and expected motion, rather than from unpreparedness to motion. APPLICATION: This study underlines the importance of an individual's anticipation to motion in motion sickness. Furthermore, this knowledge could be used in domains such as that of autonomous vehicles to reduce carsickness.