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Introduction Vection is a stationary individual's illusory experience of self-motion. This illusory self-motion is operationally important for aviation, particularly military aviation, since vection is a dramatic example of spatial disorientation (SD), which is an individual's failure to correctly sense the aircraft's position, motion, and/or attitude with respect to the fixed coordinate system of the Earth's surface and its gravitational vertical. Notably, SD is a major cause of fatal aviation mishaps, and the visual system is particularly prone to provoking vection. This article describes the Virtual Reality Vection System (VRVS), which uses computer-controlled virtual reality technology to induce vection under controlled conditions for training, demonstration, testing, and research. Materials and Methods The VRVS enables the precise specification of the number and appearance of visual stimulus elements intended to generate vection, including photorealistic images. The VRVS can present visual stimuli on any OpenXR-capable virtual reality headset. The VRVS currently records 2 types of behavioral responses, button presses to indicate the presence and duration of vection and the voltage of a handheld linear potentiometer to indicate the presence, duration, and magnitude of vection. Results An approved test plan helped guide, organize, document, and validate the VRVS during its development. Under this plan, a pair of tests guided hardware and software development of the VRVS system. Although the first test verified the ability of the VRVS to generate and measure vection, it also demonstrated that the VRVS can quickly manipulate the visual stimuli from one trial to the next so that the VRVS can support complex experimental designs. The second test used these capabilities to verify that the VRVS can characterize vection in a more analytic fashion using a masking paradigm. Specifically, the test assessed whether random stimulus elements injected into the vection-inducing stimulus disrupted vection in a quantifiable fashion. This work opens the door to studies that characterize the necessary and sufficient visual elements for vection-based SD. Discussion The VRVS is currently used to research, develop, test, and evaluate mitigation strategies targeting vection-related SD in degraded visual environments. Similarly, the VRVS is supporting research to develop methods to predict individual differences in visually induced motion sickness susceptibilities. The VRVS is currently being integrated with a precision motor-controlled rotating Barany chair for multisensory studies. It should be noted that since the VRVS was developed to support United States Army Aeromedical Research Laboratory projects, it is an Army product representing government intellectual property and may be freely available to other government institutions. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The Multi-Attribute Task Battery (MATB) is a classic aviation-like multitasking simulation platform that has amassed a rich history in performance assessment literature since its creation in 1992. Recently, the United States Army Aeromedical Research Laboratory (USAARL) has modified the traditional MATB to feature the classic task battery with upgraded features that meet the needs of current research trends in cognitive workload assessment, adaptive automation, and performance modelling. METHODS: The four subtasks used within the USAARL MATB were designed to mirror aviation tasks performed by pilots, including system monitoring, communications, compensatory tracking, and resource management. Ten unique task demand levels were designed to control the event rates of the four subtasks across a spectrum of increasing demand. Twenty-four subjects were trained in the performance of the USAARL MATB using a stepwise approach, increasing demand levels until they were unable to maintain at least a 75% average score across all subtasks during a five-minute simulation. The final demand level reached with a passing score was administered in four sequential ten-minute simulation sessions during a second laboratory visit. RESULTS: Multitasking performance was assessed through percentage of time loaded by discrete subtask events (i.e., system monitoring and communications subtask events). Multitasking performance across subjects remained consistent between measurements, showing no significant differences (Task Load (TL)0: p = 0.783; TL1: p = 0.956; TL2: p = 0.217; TL3: p = 0.627). Across demand levels, multitasking performance did show significant differences (TL0: p < 0.001; TL1: p <0.001; TL2: p = 0.004; TL3: p = 0.033), indicating a progressively increased multitasking load with higher demand levels. DISCUSSION: The USAARL MATB is poised to serve as an adaptable tool to face the challenges put forth by modern research trends in the fields of aerospace medicine and human performance. Offering unique control of dynamic task demand shifts, automation implementation, and data synchronization, the USAARL MATB allows for quick turnaround laboratory studies. The data collected in this study offers support for the training procedure and demand level event rate values included in the USAARL MATB program. The USAARL MATB software is available to be shared with collaborating institutions. Learning Objectives 1. The audience will understand the historical development of the MATB program and the motivation behind the desired functionality changes. 2. The audience will be able to identify how current research trends can leverage the custom design nature of the USAARL MATB platform in their research. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Army regulations permit aircrew of unpressurized aircraft to fly up to an altitude of 10,000 feet (ft) for an essentially unlimited duration without supplemental oxygen. The scientific literature documents the degradation of static stereo acuity (SSA) with hypoxia below 10,000 ft but is less clear about hypoxia effects on dynamic stereo acuity (DSA). Moreover, aircrew perform visually demanding, precise tasks for extended periods of time, which may be fatiguing and disruptive of binocularity when stereopsis is crucial, such as during formation flight, aerial refueling and so forth. This report describes a study of SSA and DSA in the presence of hypoxia and fatigue. METHODS: Reported here is a within-subject, repeated measures, two factor experiment with all subjects (N = 24) experiencing all conditions. One factor is the percent oxygen (O2) of inspired air with two levels, normoxia (21% O2) and a normobaric hypoxic approximation to a 10,000 ft altitude (14% O2). The second factor is testing duration with four time periods, Epochs 1-4. Each Epoch included 10 minutes of a surrogate workload task, the Multi Attribute Task Battery (MATB) and 15 minutes of vision testing that included SSA and DSA measures for a total exposure duration of 108 minutes. The primary DSA results are reported as root mean square error (RMSE) arcseconds while the SSA results are stereoacuity in arcseconds. RESULTS: The distribution of DSA RMSE values was bimodal, with 8 subjects having RMSE values approximately 56% larger than the other 16 subjects. For both groups of subjects, hypoxia significantly increased (p <= 0.006) the RMSE of DSA by about 7%. The group of 8 subjects with larger RMSE values showed an improvement (RMSE decreased) over testing Epochs, however, when hypoxic, this improvement reversed during the Epoch 4, suggesting the possible impact of fatigue combined with hypoxia. Neither hypoxia nor test duration had a statistically significant effect on SSA. DISCUSSION: Importantly, SSA was not correlated with the DSA RMSE; performance on one task did not predict the other. For selection standards, one cannot be used as a surrogate of the other. Results are discussed in terms of physiological stressors. Learning Objectives 1. To describe stereoscopic depth tracking as distinct from static stereopsis. 2. Describe the impact of hypoxia and the extended performance of a demanding task on these different types of depth perception. [ABSTRACT FROM AUTHOR]

The macular pigment (MP) is an accumulation of the carotenoids lutein, zeaxanthin, and mesozeaxanthin in the central retina. These are derived from dietary sources. MP absorbs light in the 400- to 520-nm range. Consequently, the MP is a spectral filter over the photoreceptors, reducing the effects of internally scattered light and attenuating the short wavelength component of natural sunlight. The average MP optical density (OD) is about 0.2 to 0.6 log units depending on the sample population, whereas the range of MPOD is reportedly 0 to 1.5 log units. Some people can increase their MPOD by increasing their consumption of lutein, zeaxanthin, and mesozeaxanthin, and this may be important for vision in degraded visual environments (DVE). Specifically, nutritional interventions and dietary supplements have produced statistically significant enhancements under laboratory conditions in visual tasks, such as visibility through haze, low contrast target detection, contrast sensitivity, glare resistance and recovery, photostress recovery, dark adaptation, mesopic sensitivity, and enhanced reaction times. The question is whether these enhancements are operationally meaningful or not. The present paper begins to address the question by modeling MPOD effects on the visibility to low contrast photopic and scotopic targets seen under a range of DVE over realistic distances that incorporate atmospheric filtering. Specific model parameters include luminance, target contrast, spectral content, and distance. The model can be extended to estimate the efficacy of MPOD effects on target detection, discrimination, and standoff distances. [ABSTRACT FROM AUTHOR]

'Quite possibly I believe, OZ may represent the most significant step forward in instrument flying since Elmer Sperry invented the artificial horizon in the 1920s.' That is the opinion John [...]