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The Federal Aviation Administration's effort to automate air traffic control (ATC) requires that the functionality provided today be captured in future systems. We report the first quantitative naturalistic observation of paper flight progress strip interactions during operational use. Strip use was similar in a variety of situations, but some uses varied as a function of altitude, staffing, or the cooperative style used by controller teams. Design of automation should proceed by prioritizing changes based on frequency of use and importance and should ensure that an effective method of interacting with flight information is incorporated. In addition to applied relevance to the ATC domain, the results touch on several theoretical concerns relevant to dynamic environments. Actual and potential applications of this research include the establishment of a database of strip activity and an arsenal of information valuable to system designers. [ABSTRACT FROM AUTHOR]

Objective: We provide a review and analysis of much of the published literature on binocular rivalry that is relevant to the design and use of head-worn displays (HWDs).Background: This review draws heavily from both the basic vision literature and applied HWD literature in order to help provide insight for minimizing the effects of binocular rivalry when HWDs are worn.Method: Included in this review are articles and books found cited in other works as well as articles and books obtained from an Internet search.Results: Issues discussed and summarized are (a) characteristics of binocular rivalry, (b) stimulus factors affecting rivalry, (c) cognitive variables affecting rivalry, and (d) tasks affected by rivalry.Conclusion: This paper offers a set of recommendations for minimizing the effects of binocular rivalry when HWDs are used as well as recommendations for future research.Application: Considerations of the basic vision literature on binocular rivalry will provide insight for future design solutions for HWDs. [ABSTRACT FROM AUTHOR]

Objective: We provide a review and analysis of much of the published literature on visual perception issues that impact the design and use of head-mounted displays (HMDs).Background: Unlike the previous literature on HMDs, this review draws heavily from the basic vision literature in order to help provide insight for future design solutions for HMDs.Method: Included in this review are articles and books found cited in other works as well as articles and books obtained from an Internet search.Results: Issues discussed include the effect of brightness and contrast on depth of field, dark focus, dark vergence, and perceptual constancy; the effect of accommodation-vergence synergy on perceptual constancy, eyestrain, and discomfort; the relationship of field of view to the functioning of different visual pathways and the types of visual-motor tasks mediated by them; the relationship of binocular input to visual suppression; and the importance of head movements, head tracking, and display update lag.Conclusion: This paper offers a set of recommendations for the design and use of HMDs.Application: Consideration of the basic vision literature will provide insight for future design solutions for HMDs. [ABSTRACT FROM AUTHOR]

Objective: Two experiments were conducted to examine the effects of vision and masking friction on contact perception and compliance differentiation thresholds in a simulated tissue-probing task.Background: In minimally invasive surgery, the surgeon receives limited haptic feedback because of the current design of the instrumentation and relies on visual feedback to judge the amount of force applied to the tissues. It is suggested that friction forces inherent in the instruments contribute to errors in surgeons' haptic perception. This paper investigated the psychophysics of contact detection and cross-modal sensory processing in the context of minimally invasive surgery.Method: A within-subjects repeated measures design was used, with friction, vision, tissue softness, and order of presentation as independent factors, and applied force, detection time, error, and confidence as dependent measures. Eight participants took part in each experiment, with data recorded by a custom force-sensing system.Results: In both detection and differentiation tasks, higher thresholds, longer detection times, and more errors were observed when vision was not available. The effect was more pronounced when haptic feedback was masked by friction forces in the surgical device (p < .05).Conclusion: Visual and haptic feedback were equally important for tissue compliance differentiation.Application: A frictionless endoscopic instrument can be designed to restore critical haptic information to surgeons without having to create haptic feedback artificially. [ABSTRACT FROM AUTHOR]

Objective: This paper explores the development of a rigorous computational model of driver behavior in a cognitive architecture--a computational framework with underlying psychological theories that incorporate basic properties and limitations of the human system.Background: Computational modeling has emerged as a powerful tool for studying the complex task of driving, allowing researchers to simulate driver behavior and explore the parameters and constraints of this behavior.Method: An integrated driver model developed in the ACT-R (Adaptive Control of Thought-Rational) cognitive architecture is described that focuses on the component processes of control, monitoring, and decision making in a multilane highway environment.Results: This model accounts for the steering profiles, lateral position profiles, and gaze distributions of human drivers during lane keeping, curve negotiation, and lane changing.Conclusion: The model demonstrates how cognitive architectures facilitate understanding of driver behavior in the context of general human abilities and constraints and how the driving domain benefits cognitive architectures by pushing model development toward more complex, realistic tasks.Application: The model can also serve as a core computational engine for practical applications that predict and recognize driver behavior and distraction. [ABSTRACT FROM AUTHOR]

Methodologies for assessing human judgment in complex domains are important for the design of both displays that inform judgment and automated systems that suggest judgments. This paper uses the n-system lens model to evaluate the impact of displays on human judgment and to explicitly assess the similarity between human judgments and a set of potential judgment algorithms for use in automated systems. First, the need for and concepts underlying judgment analysis are outlined. Then the n-system lens model and its parameters are formally described. This model is then used to examine a previously conducted study of aircraft collision detection that had been analyzed using standard analysis of variance methods. Our analysis found the same main effects as did the earlier analysis. However, n-system lens model analysis was able to provide greater insight into the information relied upon for judgments and the impact of displays on judgment. Additionally, the analysis was able to identify attributes of human judgments that were--and were not--similar to judgments produced by automated systems. Potential applications of this research include automated aid design and operator training. [ABSTRACT FROM AUTHOR]

This paper presents the VDM2000, a computational model of target detection designed for use in military developmental test and evaluation settings. The model integrates research results from the fields of early vision, object recognition, and psychophysics. The VDM2000 is image based and provides a criterion-independent measure of target conspicuity, referred to as the vehicle metric (VM). A large data set of human responses to photographs of military vehicles in a field setting was used to validate the model. The VM adjusted by a single calibration parameter accounts for approximately 80% of the variance in the validation data. The primary application of this model is to predict detection of military targets in daylight with the unaided eye. The model also has application to target detection prediction using infrared night vision systems. The model has potential as a tool to evaluate the visual properties of more general task settings. [ABSTRACT FROM AUTHOR]

The effects of vehicle package, seat, and anthropometric variables on posture were studied in a laboratory vehicle mockup. Participants (68 men and women) selected their preferred driving postures in 18 combinations of seat height, fore-aft steering wheel position, and seat cushion angle. Two seats differing in stiffness and seat back contour were used in testing. Driving postures were recorded using a sonic digitizer to measure the 3D locations of body landmarks. All test variables had significant independent effects on driving posture. Drivers were found to adapt to changes in the vehicle geometry primarily by changes in limb posture, whereas torso posture remained relatively constant. Stature accounts for most of the anthropometrically related variability in driving posture, and gender differences appear to be explained by body size variation. Large intersubject differences in torso posture, which are fairly stable across different seat and package conditions, are not closely related to standard anthropometric measures. The findings can be used to predict the effects of changes in vehicle and seat design on driving postures for populations with a wide range of anthropometric characteristics. [ABSTRACT FROM AUTHOR]

Objective: We examined the effects of knowledge of results (KR) on vigilance accuracy and report the first use of positive and negative predictive power (PPP and NPP) to assess vigilance training effectiveness.Background: Training individuals to detect infrequent signals among a plethora of nonsignals is critical to success in many failure-intolerant monitoring technologies. KR has been widely used for vigilance training, but the effect of the schedule of KR presentation on accuracy has been neglected. Previous research on training for vigilance has used signal detection metrics or hits and false alarms. In this study diagnosticity measures were applied to augment traditional analytic methods.Method: We examined the effects of continuous KR and a partial-KR regimen versus a no-KR control on decision diagnosticity.Results: Signal detection theory (SDT) analysis indicated that KR induced conservatism in responding but did not enhance sensitivity. However, KR in both forms equally enhanced PPP while selectively impairing NPP.Conclusion: There is a trade-off in the effectiveness of KR in reducing false alarms and misses. Together, SDT and PPP/NPP measures provide a more complete portrait of performance effects.Application: PPP and NPP together provide another assessment technique for vigilance performance, and as additional diagnostic tools, these measures are potentially useful to the human factors community. [ABSTRACT FROM AUTHOR]

Objective: The association between accidents and subsequent work unit safety perceptions was assessed to address cognitive and behavioral changes following accidents.Background: Many studies attempt to predict accident rates using measures of work unit safety, but effects vary considerably. Conversely, this study examined whether recent accidents may be positively associated with work unit safety perceptions, as suggested by behavioral learning mechanisms (increases in safety investments following accidents) or cognitive mechanisms (defensive attributions regarding accident causality).Method: Lagged squadron-level accident experience was correlated with work unit safety perceptions obtained through a 61-question safety climate survey administered to 6,361 individuals in U.S. Navy flight squadrons.Results: Positive associations between minor or intermediately severe accidents and future safety climate scores were found, although no effect was found for major accidents.Conclusion: We suggest that accident history should be considered when examining work unit safety perceptions because recent accidents may be associated with higher safety climate scores. We did not find that this varies systematically with accident severity, and longitudinal research on additional samples is needed to further test this possibility.Application: This research may be used to refine measurement of work unit safety and to examine impacts of accidents or safety violations on workers' cognitive processes and group behavioral changes. [ABSTRACT FROM AUTHOR]

Objective: Two experiments were conducted in which participants navigated a simulated unmanned aerial vehicle (UAV) through a series of mission legs while searching for targets and monitoring system parameters. The goal of the study was to highlight the qualitatively different effects of automation false alarms and misses as they relate to operator compliance and reliance, respectively.Background: Background data suggest that automation false alarms cause reduced compliance, whereas misses cause reduced reliance.Method: In two studies, 32 and 24 participants, including some licensed pilots, performed in-lab UAV simulations that presented the visual world and collected dependent measures.Results: Results indicated that with the low-reliability aids, false alarms correlated with poorer performance in the system failure task, whereas misses correlated with poorer performance in the concurrent tasks.Conclusion: Compliance and reliance do appear to be affected by false alarms and misses, respectively, and are relatively independent of each other.Application: Practical implications are that automated aids must be fairly reliable to provide global benefits and that false alarms and misses have qualitatively different effects on performance. [ABSTRACT FROM AUTHOR]

Objective: Evaluation of the effects of a PC-based training program on risk perception in a driving simulator.Background: Novice drivers have a fatality rate some eight times higher than that of the most experienced group of drivers, primarily because of the novice driver's inability to predict ahead of time the risks that will appear in the roadway. Current driver education programs, at least those in the United States, do not emphasize the teaching of risk awareness skills to novice drivers.Method: A PC-based risk awareness and perception training program was developed and evaluated. The training involved using plan (top-down) views of 10 risky scenarios that helped novice drivers identify where potential risks were located and what information should be attended. Both the 24 trained novice drivers and 24 untrained novice drivers were evaluated on an advanced driving simulator. The eye movements of both groups of drivers were measured. The evaluation on the driving simulator included both scenarios used in the training and others not used in training.Results: The set of trained novice drivers were almost twice as likely as untrained drivers to fixate appropriately either on the regions where potential risks might appear or on signs that warned of potentially risky situations ahead, both for the scenarios they had encountered in training and for novel scenarios.Application: The PC training program developed, which is portable and can be widely used, has great promise in improving risk perception for novice drivers on the road. [ABSTRACT FROM AUTHOR]

Objective: This review provides the state of crew resource management (CRM) training evaluations since the E. Salas, C. S. Burke, C. A. Bowers, and K. A. Wilson (2001) review and extends it to areas beyond aviation cockpits. Some critical evaluation needs in CRM training are also covered.Background: Because of the purported success of CRM training in aviation, other high-consequence domains have begun to implement CRM training for their workforces. However, the true impact of CRM training in aviation and these other domains has yet to be determined.Method: Using D. L. Kirkpatrick's (1976) framework for evaluating training (i.e., reactions, learning, behavior, and organizational impact), we reviewed 28 published accounts of CRM training to determine its effectiveness within aviation, medicine, offshore oil production and maintenance, shipping/maritime, and nuclear power domains.Results: Findings indicate that CRM training generally produced positive reactions from trainees; however, the impact of training on learning and behavioral changes suggest mixed results across and within domains. Furthermore, and as was found by Salas, Burke, et al. in 2001, we cannot ascertain whether CRM has had an impact on the organization's bottom line (i.e., safety).Conclusion: Based on the results, there are several critical needs that the CRM training community must address before CRM training can have the desired impact on safety: a mandate, access to data, and resources.Application: As CRM training expands to organizations beyond aviation, it is critical that its impact be understood such that it can be improved and achieve the intended results. [ABSTRACT FROM AUTHOR]

Objective: The performance costs associated with cell phone use while driving were assessed meta-analytically using standardized measures of effect size along five dimensions.Background: There have been many studies on the impact of cell phone use on driving, showing some mixed findings.Methods: Twenty-three studies (contributing 47 analysis entries) met the appropriate conditions for the meta-analysis. The statistical results from each of these studies were converted into effect sizes and combined in the meta-analysis.Results: Overall, there were clear costs to driving performance when drivers were engaged in cell phone conversations. However, subsequent analyses indicated that these costs were borne primarily by reaction time tasks, with far smaller costs associated with tracking (lane-keeping) performance. Hands-free and handheld phones revealed similar patterns of results for both measures of performance. Conversation tasks tended to show greater costs than did information-processing tasks (e.g., word games). There was a similar pattern of results for passenger and remote (cell phone) conversations. Finally, there were some small differences between simulator and field studies, though both exhibited costs in performance for cell phone use.Conclusion: We suggest that (a) there are significant costs to driver reactions to external hazards or events associated with cell phone use, (b) hands-free cell phones do not eliminate or substantially reduce these costs, and (c) different research methodologies or performance measures may underestimate these costs.Application: Potential applications of this research include the assessment of performance costs attributable to different types of cell phones, cell phone conversations, experimental measures, or methodologies. [ABSTRACT FROM AUTHOR]

Objective: The goals of this study were to understand the reasons underlying the limited use of medical decision-support tools and to explore the potential of a computer-based tutorial to mitigate barriers to use.Background: Medical decision-support tools such the Acute Cardiac Ischemia Time-Insensitive Predictive Instrument (ACI-TIPI) have demonstrated statistical validity and clinical impact for patient safety but have seen limited adoption and use.Methods: The study developed a brief Web-based "demystifying" ACI-TIPI tutorial employing case-based training and evaluated the effectiveness of that tutorial in changing self-reported attitudes and behaviors.Results: Clinicians using the tutorial reported greater understanding of how to use the ACI-TIPI score appropriately and increased confidence in the score. Case studies in the tutorial that provided examples of how to use the score for actual cases were rated as especially helpful.Conclusion: This study suggests that a primary barrier to the use of statistical decision support tools for patient diagnosis is lack of training or experience in combining a population-based numerical risk score with other diagnostic information about the individual patient's case that is not considered in that score. The results of this study indicate that there is a potential for a relatively brief tutorial to increase acceptance and use of decision support tools for medical diagnosis.Application: These findings have the potential for the identification of methods to help clinicians learn how to use statistical and probabilistic information to better assess risk and to promote integration of decision support tools into medical decision making for improvement of patient safety. [ABSTRACT FROM AUTHOR]

Objective: To better understand nursing activities and working conditions.Background: Nursing practice involves astute clinical decision making and the competent delivery of nursing care procedures. To complete nursing procedures, nurses must simultaneously organize and reorganize priorities and manage changing clinical information for multiple patients. Few researchers have examined the specific nature of nurses' activities and the effect of the environment on their work.Methods: Quantitative and qualitative methods were used to collect data on 7 nurses engaged in nursing activities. Examples of methods include link analysis, subject matter expert, task analysis, cognitive pathway, and "stacking." Data collection focused on how nurses managed priorities, changing clinical information, and interruptions.Results: The "cognitive pathway" graphically depicts the nature of nurses' work. Specifically, it reveals the shifting of the nurse's attention from patient to patient and the occurrence of interruptions. "Stacking" shows the number of tasks a nurse must balance at any one time. On average, nurses had 10 or more activities waiting to be performed and experienced 3.4 interruptions/hr.Conclusion: These methods provide unique insight into the dynamic nature of patient care and nursing work.Application: Extension of the methods demonstrated here may be useful in guiding efforts to change the work of nursing to better provide quality care and less stressful work environments. [ABSTRACT FROM AUTHOR]

Objective: To identify the types and extent of workaround strategies with the use of Bar Code Medication Administration (BCMA) in acute care and long-term care settings.Background: Medication errors are the most commonly documented cause of adverse events in hospital settings. Scanning of bar codes to verify patient and medication information may reduce medication errors.Method: A prospective ethnographic study was conducted using targeted observation. Fifteen acute care and 13 long-term care nurses were directly observed during medication administration at small, medium, and large Veterans Administration hospitals to detect workaround strategies.Results: Noncompliance with recommended practices was observed in all settings and facilities. A larger proportion of acute care nurses than long-term care nurses scanned bar-coded wristbands to identify patients (53% vs. 8%, p = .016). A larger proportion of acute care nurses than long-term care nurses administered bar-coded medications immediately after scanning (93% vs. 23%, p < .001).Conclusion: Workaround strategies were employed with BCMA that increased efficiency but created new potential paths to adverse events. There was a significant difference in the rate of use of workaround strategies between acute and long-term care.Application: The extent of workaround strategies varied by care setting and facility. BCMA should be tailored to the long-term care setting, including increasing the efficiency of use. Hospitals implementing bar coding should facilitate the intended use through equipment procurement, implementation, and quality improvement strategies. [ABSTRACT FROM AUTHOR]

Useful field of view, a measure of processing speed and spatial attention, can be improved with training. We evaluated the effects of this improvement on older adults' driving performance. Elderly adults participated in a speed-of-processing training program (N = 48), a traditional driver training program performed in a driving simulator (N = 22), or a low-risk reference group (N = 25). Before training, immediately after training or an equivalent time delay, and after an 18-month delay each participant was evaluated in a driving simulator and completed a 14-mile (22.5-km) open-road driving evaluation. Speed-of-processing training, but not simulator training, improved a specific measure of useful field of view (UFOV), transferred to some simulator measures, and resulted in fewer dangerous maneuvers during the driving evaluation. The simulator-trained group improved on two driving performance measures: turning into the correct lane and proper signal use. Similar effects were not observed in the speed-of-processing training or low-risk reference groups. The persistence of these effects over an 18-month test interval was also evaluated. Actual or potential applications of this research include driver assessment and/or training programs and cognitive intervention programs for older adults. [ABSTRACT FROM AUTHOR]

The assessment of expertise is vital both in practical situations that call for expert judgment and in theoretical research on the psychology of experts. It can be difficult, however, to determine whether a judge is in fact performing expertly. Our goal was to develop an empirical measure of expert judgment. We argue that two necessary characteristics of expertise are discrimination of the various stimuli in the domain and consistent treatment of similar stimuli. We combine measures of these characteristics to form a ratio we call the Cochran-Weiss-Shanteau (CWS) index of expertise. The proposed index was demonstrated using two studies that distinguished experts from nonexperts based on their judgmental performance. The index provides new insights into expertise and offers a partial definition of expertise that may be useful in a variety of theoretical and applied settings. Potential applications of this research include selection, training, and evaluation of experts and of expert-machine systems. [ABSTRACT FROM AUTHOR]

Rear-end collisions account for almost 30% of automotive crashes. Rear-end collision avoidance systems (RECASs) may offer a promising approach to help drivers avoid these crashes. Two experiments performed using a high-fidelity motion-based driving simulator examined driver responses to evaluate the efficacy of a RECAS. The first experiment showed that early warnings helped distracted drivers react more quickly--and thereby avoid more collisions--than did late warnings or no warnings. Compared with the no-warning condition, an early RECAS warning reduced the number of collisions by 80.7%. Assuming collision severity is proportional to kinetic energy, the early warning reduced collision severity by 96.5%. In contrast, the late warning reduced collisions by 50.0% and the corresponding severity by 87.5%. The second experiment showed that RECAS benefits even undistracted drivers. Analysis of the braking process showed that warnings provide a potential safety benefit by reducing the time required for drivers to release the accelerator. Warnings do not, however, speed application of the brake, increase maximum deceleration, or affect mean deceleration. These results provide the basis for a computational model of driver performance that was used to extrapolate the findings and identify the most promising parameter settings. Potential applications of these results include methods for evaluating collision warning systems, algorithm design guidance, and driver performance model input. [ABSTRACT FROM AUTHOR]

Two experiments examined pilots' maneuver choice and visual workload in a free-flight simulation. In Experiment 1, 12 pilots flew a high-fidelity flight simulator with a cockpit display of traffic information and maneuvered to avoid traffic in a simulated free-flight environment. Pilots' choices reflected a preference to make vertical rather than lateral avoidance maneuvers and to climb rather than descend. Pilots avoided both complex maneuvers and airspeed maneuvers. The data were modeled in terms of how pilots traded off factors related to safety, efficiency, mental effort, and prior habits. In Experiment 2, 10 pilots flew the same maneuvers as the pilots in Experiment 1 but followed ATC instructions rather than using the CDTI. The CDTI in Experiment 1 occupied 25% of the pilots' visual attention. A comparison of scanning with Experiment 2 suggested that the CDTI pulled visual attention away from the outside world, but this attention diversion did not leave pilots vulnerable to missing traffic not annunciated on the CDTI. Actual or potential applications of the results include understanding the safety implications of presenting traffic displays in the cockpit, and the impact of pilot maneuver preferences on airspace procedures. [ABSTRACT FROM AUTHOR]

Findings that decision makers can come to different conclusions depending on the order in which they receive information have been termed the "information order bias." When trained, experienced individuals exhibit similar behaviors; however, it has been argued that this result is not a bias, but rather, a pattern-matching process. This study provides a critical examination of this claim. It also assesses both experts' susceptibility to an outcome framing bias and the effects of varying task loads on judgment. Using a simulation of state-of-the-art ship defensive systems operated by experienced, active-duty U.S. Navy officers, we found no evidence of a framing bias, while task load had a minor, but systematic effect. The order in which information was received had a significant impact, with the effect being consistent with a judgment bias. Nonetheless, we note that pattern-matching processes, similar to those that produce inferential and reconstructive effects on memory, could also explain our results. Actual or potential applications of this research include decision support system interfaces or training programs that might be developed to reduce judgment bias. [ABSTRACT FROM AUTHOR]

We used 3 psychophysics methods to determine perceptible changes in seat height, seat pan angle, and backrest angle using an experimental chair. In the method of adjustment, the chosen chair settings were affected by the initial setting. For example, a high initial setting of the seat height led to a high selected setting and a low setting led to a low value. The difference between settings was referred to as not noticeable difference (NND). The method of limits was used to determine acceptable chair settings using verbal limits such as "too high" and "too low." Using the method of constant stimuli, just noticeable differences (JNDs) were determined for chair height (1.5 cm), seat pan angle (1.2 degrees) and backrest angle (1.7 degrees). The corresponding values for NNDs and verbal limits were about twice as large: chair height (2.5 cm), seat pan angle (4 degrees) and backrest angle (3 degrees). NNDs and verbal limits are unobtrusive measures that are considered more valid than JNDs, which exaggerate the need for adjustability. The results have practical implications for the design of office chairs. [ABSTRACT FROM AUTHOR]

Recent free flight proposals to relax airspace constraints and give greater autonomy to aircraft have raised concerns about their impact on controller performance. Relaxing route and altitude restrictions would reduce the regularity of traffic through individual sectors, possibly impairing controller situation awareness. We examined the impact of this reduced regularity in four visual search experiments that tested controllers' detection of traffic conflicts in the four conditions created by factorial manipulation of fixed routes (present vs. absent) and altitude restrictions (present vs. absent). These four conditions were tested under varying levels of traffic load and conflict geometry (conflict time and conflict angle). Traffic load and conflict geometry showed strong and consistent effects in all experiments. Color coding altitude also substantially improved detection times. In contrast, removing altitude restrictions had only a small negative impact, and removing route restrictions had virtually no negative impact. In some cases conflict detection was actually better without fixed routes. The implications and limitations of these results for the feasibility of free flight are discussed. Actual or potential applications include providing guidance in the selection of free flight operational concepts. [ABSTRACT FROM AUTHOR]

Traditionally military aviators have prepared for air-to-ground bombing missions with maps and aerial photographs of their targets. Mission rehearsal systems augment these media by allowing pilots to view simulated ingress to their target, as seen from the cockpit perspective. In the present experiment we assessed the benefits of mission rehearsal with a task requiring observers to view recorded approaches to target objects and to detect the target objects as quickly as possible. Results indicated that premission simulations allowed observers to detect target objects at greater stand-off ranges than did study with maps and aerial photographs alone. Actual or potential applications of this research include the deployment of a mission rehearsal system to assist aviators' mission planning. [ABSTRACT FROM AUTHOR]

Two experiments were performed to examine how frame of reference (world-referenced vs. screen-referenced) and target expectancy can modulate the effects of target cuing in directing attention for see-through helmet-mounted displays (HMDs). In the first experiment, the degree of world referencing was varied by the spatial accuracy of the cue; in the second, the degree of world referencing was varied more radically between a world-referenced HMD and a hand-held display. Participants were asked to detect, identify, and give azimuth information for targets hidden in terrain presented in the far domain (i.e., the world) while performing a monitoring task in the near domain (i.e., the display). The results of both experiments revealed a cost-benefit trade-off for cuing such that the presence of cuing aided the target detection task for expected targets but drew attention away from the presence of unexpected targets in the environment. Analyses support the observation that this effect can be mediated by the display: The world-referenced display reduced the cost of cognitive tunneling relative to the screen-referenced display in Experiment 1; this cost was further reduced in Experiment 2 when participants were using a hand-held display. Potential applications of this research include important design guidelines and specifications for automated target recognition systems as well as any terrain-and-targeting display system in which superimposed symbology is included, specifically in assessing the costs and benefits of attentional cuing and the means by which this information is displayed. [ABSTRACT FROM AUTHOR]

Using an eye-tracking methodology, we evaluated food nutrition labels' ability to support rapid and accurate visual search for nutrition information. Participants (5 practiced label readers and 5 nonreaders) viewed 180 trials of nutrition labels on a computer, finding answers to questions (e.g., serving size). Label manipulations included several alternative line arrangements, location of the question target item, and label size. Dependent measures included search time and number of fixations prior to visually capturing the target, as well as the accuracy and duration of the capturing fixation. Practiced label readers acquired the target more quickly and accurately than did less-practiced readers. Targets near the denser center of the label required 33% more time and were harder to find than targets at the top or bottom of the label. Thinner alignment lines were more influential than thicker anchoring lines on visual search time. Overall, the current nutrition label supported accurate and rapid search for desired information. Potential applications of the present methodology include the evaluation of warning labels and other static visual displays. [ABSTRACT FROM AUTHOR]