PURPOSE: To determine the equivalence of the ColorDx Military Research version (mColorDx) test and three printed pseudoisochromatic tests (HRR, Ishihara, and PIPIC) for color vision testing.METHODS: Participating in the study were 75 color-normals and 47 subjects with red-green color vision defects. Color vision was classified by an anomaloscope. The HRR (4^th edition), Ishihara 38-plate edition, and PIPIC tests are printed color vision tests, whereas mColorDx test figures were displayed on a calibrated computer desktop monitor. All tests were repeated in about 1 wk.RESULTS: The kappa level of agreement (κ) values with the anomaloscope for screening for each test was 0.96 or greater. The values were statistically identical. Specificity for each test was at least 0.99 and sensitivity was at least 0.95. The repeatability of the screening sections for all tests was very good with κ values greater than 0.95. Deutans tended to miss the tritan screening plates on the HRR and mColorDx tests. The Spearman rank correlation coefficients between the severity of the defect and anomaloscope range was moderate with r = 0.45 for the mColorDx and r = 0.6 for the HRR. Both the mColorDx and HRR had perfect agreement with the anomaloscope in classifying the defects as either protan or deutan.CONCLUSION: The validity of the four tests for color vision screening was statistically identical; however, the HRR may be preferred because it had the highest sensitivity of 0.99, a specificity of 1.0, and a reasonable correlation between the severity rating of the defect and the anomaloscope range.Almustanyir A, Hovis JK. Military Research ColorDX and printed color vision tests. Aerosp Med Hum Perform. 2015; 86(10):852–859.

INTRODUCTION: The neural mechanisms underlying the influence of chronic exposure to high altitude on performance monitoring are not clear. We investigated performance monitoring in the context of chronic exposure to high altitude.METHODS: A go/no-go task was used to obtain event-related potentials (ERP). The error-related negativity (ERN), correct-related negativity (CRN), and error positivity (Pe) components were measured in high-altitude and low-altitude groups. The high-altitude group had lived at high altitude for 3 yr, but were born and raised at low altitude, whereas the low-altitude group had lived at low altitude only.RESULTS: The ERN amplitudes were larger in the high-altitude group compared with the low-altitude group (−14.00 ± 8.34 μV vs. −7.82 ± 8.42 μV, respectively). Moreover, the CRN amplitudes were larger in the high-altitude group (3.51 ± 4.50 μV vs. 8.65 ± 3.23 μV, respectively). Group differences were not significant for the Pe component.DISCUSSION: These results suggest that chronic exposure to high altitude can cause overactive performance monitoring in the high-altitude group, but the later stage of error monitoring was not influenced.Ma H, Wang Y, Wu J, Liu H, Luo P, Han B. Overactive performance monitoring resulting from chronic exposure to high altitude. Aerosp Med Hum Perform. 2015; 86(10):860–864.

INTRODUCTION: This study investigated how operation complexity and type affect Chinese individuals’ performance of simulated spaceflight operations under conditions of sleep deprivation and confinement (SDC).METHODS: There were 20 male volunteers who were randomly divided into 2 groups: the SDC group (N = 8) and the control group (N = 12). During the 72-h experimental period, the volunteers were asked to perform 11 computerized spaceflight emergency procedures, varying in operation complexity and type, three times at the 9^th, 33^rd, and 57^th hours, respectively. Operation times and errors of each spaceflight emergency procedure were recorded. Three complexity levels (i.e., low complexity, high complexity, and combined complexity) and three operation types (i.e., two-way judgment, manual operation, and mixed operation) were identified according to an operation complexity measure and an engineering definition.RESULTS: Mixed model ANOVAs indicated that performance of the three complex operations and three operation types were negatively affected by SDC. Moreover, the results showed that the operation time of manual operation (10.67 ± 1.706 at the 9^th hour, 13.94 ± 4.261 at the 33^rd hour) and mixed operation (4.88 ± 0.247 at the 9^th hour, 5.15 ± 1.308 at the 57^th hour) increased significantly with the increase of waking time. It was also shown that the high complexity operation and manual operation got less variation in operation time compared with low complexity and two-way judgment, respectively.CONCLUSIONS: The result indicated that the task assignment with high complexity requiring cognition could be a useful way to counteract the effect of SDC. It was also implied that psychomotor abilities were more easily affected by SDC than perception and judgment.Zhang Y, Li Z, Liu X, Liu F, Jing X, Wu B. Simulated spaceflight operations under sleep deprivation and confinement. Aerosp Med Hum Perform. 2015; 86(10):865–874.

BACKGROUND: Physical fitness and dehydration are factors that may influence cardiac autonomic control. We aimed to verify the influence of these factors on cardiac autonomic control before, during, and after a flight.METHODS: At the same time of day, 11 healthy fighter pilots recorded several 1-h bouts of heart rate (HR) activity during a non- (control) and a training flight day. Autonomic control of HR was examined via time domain and non-linear heart rate variability (HRV) analyses. The level of dehydration during the flight was evaluated by changes in hematocrit, while aerobic capacity, muscular strength, and body fatness were the physical fitness components evaluated.RESULTS: The flight induced a significant reduction in most parameters of HRV during flight time when compared to the control day. However, no differences were found between the days before the flight, while the root mean square of successive differences (RMSSD) of HR was the only parameter significantly reduced (11.05 ± 7.7%) after the flight. Significant correlations were observed between the sample entropy of HR during flight and aerobic capacity (r = 0.777) and body fatness (r = −0.617). Correlations between dehydration and changes in HRV (RMSSD and SD1) were also identified (r = −0.61 to −0.81).CONCLUSION: The current results demonstrated significant relationships between aerobic capacity, body fatness, and hydration status on autonomic control of HR during and after flights. No relationship to muscular strength was observed. Future studies may further elucidate the impact of these factors on pilot training in order to accommodate flight’s stressors and enhance performance.Oliveira-Silva I, Boullosa DA. Physical fitness and dehydration influences on the cardiac autonomic control of fighter pilots. Aerosp Med Hum Perform. 2015; 86(10):875–880.

BACKGROUND: Over the past 10-15 yr, considerable research has occurred for the development, testing, and fielding of real-time Datalink weather products for general aviation (GA) pilots to use before and during flight. As is the case with the implementation of most new technologies, work is needed to ensure that the users (in this case, the pilots) understand both the capabilities and limitations of the new technologies as well as how to use the new systems to improve their task performance. The purpose of this study was to replicate and extend a previous study on training pilots how and when to use these new weather technologies.METHOD: This field study used a quasi-experimental design (pre- vs. post-test with a control group). There were 91 GA pilots from the Midwest, Northeastern, and Southeastern United States who participated in a 2-h short course or a control activity. The lecture-based short course covered radar basics, Next Generation Weather Radar (NEXRAD), NEXRAD specifics/limitations, thunderstorm basics, radar products, and decision making.RESULTS: The pilots who participated in the course earned higher knowledge test scores, improved at applying the concepts in paper-based flight scenarios, had higher self-efficacy in post-training assessments as compared to pre-training assessments, and also performed better than did control subjects on post-test knowledge and skills assessments.DISCUSSION: GA pilots lack knowledge about real-time Datalink weather technology. This study indicates that a relatively short training program was effective for fostering Datalink weather-related knowledge and skills in GA pilots.Blickensderfer EL, Lanicci JM, Vincent MJ, Thomas RL, Smith M, Cruit JK. Training general aviation pilots for convective weather situations. Aerosp Med Hum Perform. 2015; 86(10):881–888.

BACKGROUND: The purpose of this study was to determine if five core strengthening exercises would decrease pain severity and related disability in U.S. Air Force helicopter aircrew members with low back pain.METHODS: The study was a randomized control group repeated measures design. The experimental manipulation consisted of a set of five core strengthening exercises performed 4 d/wk for 12 wk. Self-reported pain severity and disability were ascertained at baseline and 12 wk using the Numerical Pain Rating Scale (NPRS) and Modified Oswestry Low Back Pain Disability Index (MODI), respectively. The NPRS was used to ascertain both daily pain (NPRS_daily) and in-flight pain (NPRS_flight). Self-reported improvement or deterioration in low back pain was measured using the Global Rating of Change Scale (GRCS).RESULTS: There were 12 subjects enrolled and 5 were randomized to the intervention group. The mean NPRS_flight score decreased 1.8 points vs. increasing 0.1 points during the trial for the intervention and control groups, respectively. The mean MODI score decreased 4.8 points vs. increasing 1.7 points during the trial for the intervention and control groups, respectively. The mean GRCS score at the end of the trial was 4.0 vs. 0 for the intervention and control groups, respectively. There was no difference between groups in terms of mean NPRS_daily scores.CONCLUSIONS: Core strengthening exercises were effective in reducing in-flight pain and led to a reduction in pain symptoms and disability over the 12-wk study period as compared to those subjects who maintained their regular exercise regimen.Brandt Y, Currier L, Plante TW, Schubert Kabban CM, Tvaryanas AP. A randomized controlled trial of core strengthening exercises in helicopter crewmembers with low back pain. Aerosp Med Hum Perform. 2015; 86(10):889–894.

BACKGROUND: Air traffic controllers (ATC) work shifts and their work schedules vary according to the characteristics of each airport. The human body adapts to shiftwork differently. These adjustments affect the health-disease process, predisposing ATC to risk conditions associated with sleep deprivation and lack of night sleep, which can lead to conditions such as cardiovascular diseases, mood disorders, anxiety, and obesity. This study investigated the characteristics of health, sleep, and quality of life of ATC exposed to 8-h alternate work shifts and 6-h rotational work shifts.METHODS: The study was cross-sectional with convenience samples consisting of 84 ATC from two international airports in Brazil. We applied questionnaires to collect data about socioeconomic conditions, quality of life, sleep, and physical activity levels. We also collected health data regarding nutritional status, body composition, and blood pressure. We analyzed the differences between ATC from the two airports considering the variables of sleep, quality of life, and health.RESULTS: Differences were found between the groups in terms of body fat percentage (30.7% and 27.8%), scores of overall quality of life (56.2 and 68), concentration (3.37 and 3.96), energy (3.12 and 3.62), and sleep time on working days (5:20 h and 6:15 h).CONCLUSION: ATC under 8-h alternate shifts showed lower scores for quality of life, higher body fat, and less sleep time on working days, which characterizes inadequate shiftwork for this population.Sonati J, De Martino M, Vilarta R, Maciel É, Moreira E, Sanchez F, De Martino G, Sonati R. Quality of life, health, and sleep of air traffic controllers with different shift systems. Aerosp Med Hum Perform. 2015; 86(10):895–900.

INTRODUCTION: Environmental motion can affect shipboard sleep of crewmembers. Slamming and similar harsh motion may interfere with sleep, whereas mild motion and sopite syndrome may enhance sleep. If sleep needs vary by sea condition, this factor should be considered when assessing human performance at sea. The goal of this study was to assess sleep duration in different sea conditions.METHODS: Crewmembers (N = 52) from a U.S. Navy vessel participated in the study while performing their normal daily schedule of duties. Sleep was assessed with wrist-worn actigraphy. Motion sickness and sopite syndrome were assessed using standardized questionnaires.RESULTS: In rough sea conditions, crewmembers experienced increased severity of motion sickness and sopite syndrome compared to their ratings during calmer sea conditions. Crewmembers slept significantly longer during sea state 5-6 compared to sleep on days with sea state 4 (25% increase) and sea state 3-4 (30% increase). Specifically, daily sleep increased from 6.97 ± 1.24 h in sea state 3-4, to 7.23 ± 1.65 h in sea state 4, to 9.04 ± 2.90 h in sea state 5–6.DISCUSSION: Although the duration of sleep in rough seas increased significantly compared to calmer sea conditions, causal factors are inconclusive. Accumulated sleep debt, motion-induced fatigue, and sopite syndrome all may have contributed, but results suggest that motion sickness and sopite syndrome were the predominant stressors. If sleep needs increase in severe motion environments, this factor should be taken into account when developing daily activity schedules or when modeling manning requirements on modern ships.Matsangas P, Shattuck NL, McCauley ME. Sleep duration in rough sea conditions. Aerosp Med Hum Perform. 2015; 86(10):901–906.

BACKGROUND: Acute and chronic spinal symptoms such as neck pain may limit flying performance significantly and disqualify the pilot from flight duty. Mechanical neck pain is very common among pilots because of their exposure to vibration, +G_Z forces, helmet weight, poor neck posture during air combat maneuvers, previous neck injuries, and poor treatment plans for such injuries. Successful treatment of such injuries requires appropriate therapeutic procedures as well as an aeromedical assessment. The aim of this case study was to demonstrate the benefits of conservative procedures such as spinal manipulation and mobilization therapy (SMMT) and exercise therapy (ET) in treating chronic mechanical neck pain in an Iranian commercial helicopter pilot.CASE REPORT: A 36-yr-old male patient presented to the clinic with moderate, intermittent nonradicular chronic neck pain and limited range of motion over a 2-yr period. The patient was treated with cervical and upper thoracic SMMT followed by home ET for 5 wk. After this period, the patient reported significant recovery and improvement in range of motion in his neck.DISCUSSION: Mechanical neck pain is very common among helicopter pilots. Although Air Force and Navy waiver guides recommend nonsteroidal anti-inflammatory medications as well as SMMT and ET, there are currently very few published studies that examine the benefits of manual and exercise therapy for treating mechanical neck pain in commercial and military pilots. Based on the results of this study, it seems that SMMT and ET may be a safe and effective in treatment of uncomplicated mechanical neck pain in helicopter pilots.Alagha B. Conservative management of mechanical neck pain in a helicopter pilot. Aerosp Med Hum Perform. 2015; 86(10):907–910.

INTRODUCTION: The first off-Earth fused deposition modeling (FDM) 3D printer is investigating acrylonitrile butadiene styrene (ABS) thermoplastic manufacturing applications for long-duration space missions. This study assessed the feasibility of FDM 3D printing ABS thermoplastic customized mallet splints on site for Mars analogue crewmembers.METHODS: Seven caliper measurements were taken of the right ring finger of 13 healthy Mars Desert Research Station mission crewmembers. These measurements were input into a free 3D modeling software program to create customized digital splint models. These digital files were uploaded to a desktop FDM 3D printer and custom splints were printed on site with ABS thermoplastic. Splint fit was assessed via subject feedback. Joint active range of motion was recorded when the splint was worn briefly.RESULTS: The time it took the software program to digitally render each splint model was less than 2 min and 30 s. The print duration for the splints ranged from 21 to 29 min. All 13 subjects reported that their 3D printed custom mallet splints fit securely and comfortably. All splints permitted full active range of motion of the proximal interphalangeal joint (0–100°) while maintaining the distal interphalangeal joint in extension.DISCUSSION: It is feasible to 3D print functional ABS thermoplastic custom mallet splints on site for Mars analogue crewmembers. This technology could be used clinically in the future when a custom mallet splint is required in a remote, resource-constrained setting.Wong JY. On-site 3D printing of functional custom mallet splints for Mars analogue crewmembers. Aerosp Med Hum Perform. 2015; 86(10):911–914.

INTRODUCTION: In Germany, the German Federal Police assess the performance of aviation security screeners on a regular basis. These so-called “reality tests” are unannounced examinations which aim to investigate whether airport screeners can detect forbidden items in hand luggage or attached to the body. Recent alarming results of such inspections showed clearly that the overall detection rate is in need of improvement. To achieve this, it is important to identify specific factors that influence general screening performance. This especially includes basic cognitive functions like visual screening, alertness, and divided attention, which have come more and more into focus in current fundamental research projects. This brief commentary points out critical factors, contributes background conditions in aviation security screening, and shows possible approaches for enhancement and optimization. Finally, the human aspect is discussed as not only being the weakest factor in security screening, but also one of major importance.Kruger JK, Suchan B. Humans are still the critical factor in aviation security. Aerosp Med Hum Perform. 2015; 86(10):915–917.

Cagniart P-EC. You’re the flight surgeon: Miller-Fischer syndrome. Aerosp Med Hum Perform. 2015; 86(10):918–920.

Lee M. You’re the flight surgeon: vitamin A toxicity. Aerosp Med Hum Perform. 2015; 86(10):920–922.