INTRODUCTION: The coordination of team effort on shared tasks is an area of inquiry. A number of tests of team performance in challenging environments have been developed without comparison or standardization. This article provides a systematic review of the most accessible and usable low-to-medium fidelity computerized tests of team performance and determines which are most applicable to military- and aviation-relevant research, such as studies of group command, control, communication, and crew coordination.METHODS: A search was conducted to identify computerized measures of team performance. In addition to extensive literature searches (DTIC, Psychinfo, PubMed), the authors reached out to team performance researchers at conferences and through electronic communication.RESULTS: Identified were 57 potential tests according to 6 specific selection criteria (e.g., the requirement for automated collection of team performance and coordination processes, the use of military-relevant scenarios). The following seven tests (listed alphabetically) were considered most suitable for military needs: Agent Enabled Decision Group Environment (AEDGE), C3Conflict, the C³ (Command, Control, & Communications) Interactive Task for Identifying Emerging Situations (NeoCITIES), Distributed Dynamic Decision Making (DDD), Duo Wondrous Original Method Basic Awareness/Airmanship Test (DuoWOMBAT), the Leader Development Simulator (LDS), and the Planning Task for Teams (PLATT). Strengths and weaknesses of these tests are described and recommendations offered to help researchers identify the test most suitable for their particular needs.DISCUSSION: Adoption of a few standard computerized test batteries to study team performance would facilitate the evaluation of interventions intended to enhance group performance in multiple challenging military and aerospace operational environments.Lawson BD, Britt TW, Kelley AM, Athy JR, Legan SM. Computerized tests of team performance and crew coordination suitable for military/aviation settings. Aerosp Med Hum Perform. 2017; 88(8):722–729.

BACKGROUND: Treadmills have been employed as both a form of exercise and a countermeasure to prevent changes in the musculoskeletal system on almost all NASA missions and many Russian missions since the early Space Shuttle flights. It is possible that treadmills may also be part of exercise programs on future Mars missions and that they may be a component of exercise facilities in lunar or Martian habitats.METHODS: In order to determine if the ambient gravity on these destinations will provide osteogenic effects while performing exercise on a treadmill, ground reactions forces (GRFs) were measured on eight subjects (six women and two men) running at 6 mph during parabolic flight in Martian and lunar gravity conditions.RESULTS: On average, stride length increased as gravity decreased. The first and second peaks of the GRFs decreased by 0.156 and 0.196 bodyweights, respectively, per 1/10 g change in ambient gravity.DISCUSSION: Based on comparisons with previously measured GRF during loaded treadmill running on the International Space Station, we conclude that unloaded treadmill running under lunar and Martian conditions during exploration missions is not likely to be an osteo-protective exercise.Cavanagh P, Rice A, Glauberman M, Sudduth A, Cherones A, Davis S, Lewis M, Hanson A, Wilt G. Ground reaction forces during reduced gravity running in parabolic flight. Aerosp Med Hum Perform. 2017; 88(8):730–736.

BACKGROUND: G-induced loss of consciousness (G-LOC) is mainly caused by failure to sustain an oxygenated blood supply to the pilot’s brain because of the sudden acceleration in the direction of the +G_z axis, and is considered a critical safety issue. The purpose of this study was to develop G-LOC warning algorithms based on monitoring electromyograms (EMG) of the gastrocnemius muscle on the calf.METHODS: EMG data was retrieved from a total of 67 pilots and pilot trainees of the Korean Air Force during high-G training on a human centrifugal simulator. Seven EMG features were obtained from root mean square (RMS), integrated absolute value (IAV), and mean absolute value (MAV) for muscle contraction, slope sign changes (SSC), waveform length (WL), zero crossing (ZC), and median frequency (MF) for muscle contraction and fatigue.RESULTS: Out of seven EMG features, IAV and WL showed a rapid decay before G-LOC. Based on these findings, this study developed two algorithms which can detect G-LOC during flight and provide warning signals to the pilots. The probability of G-LOC occurrence was detected through monitoring the decay trend for representing muscle endurance and climb rate of the IAV and WL value during sudden acceleration above 6 G, representing muscle power. The sensitivity of the algorithms using IAV and WL features was 100% and the specificity was 66.7%.DISCUSSION: This study suggests that a G-LOC detecting and warning system may be a customized, real-time countermeasure by improving the accuracy of detecting G-LOC.Kim S, Cho T, Lee Y, Koo H, Choi B, Kim D. G-LOC warning algorithms based on EMG features of the gastrocnemius muscle. Aerosp Med Hum Perform. 2017; 88(8):737–742.

BACKGROUND: Human performance modeling plays an important role in the design and management of human spaceflight missions. Previous studies reported that manual control task time increased in microgravity conditions. The current study aimed to find a modeling method that can quantify and predict the task time of spacecraft control panel operation in the simulated microgravity condition.METHODS: We proposed the application of a predetermined elemental task method together with an information processing time model to quantify both physical motion time and cognitive time. The time increment due to microgravity was hypothesized to be proportional to physical motion time. The total task time in the microgravity condition could be calculated as the model time from the normal ground condition plus the predicted time increment. Human data were collected from an experiment asking participants to perform six emergency operating procedure tasks in both normal ground and simulated microgravity conditions.RESULTS: The proposed method resulted in good fitness to human data in both conditions, as shown by both regression fitness (R² values = 0.99) and modeling error measures (root mean square error ≤ 3.3 s; mean absolute percentage error ≤ 16.1%).CONCLUSIONS: Although the method has its limitations, the current findings suggest that it has value in aerospace human factors and ergonomics applications.Cao S, Zhang Y, Guo Y, Chen S. Human performance time model of spacecraft control panel operation in simulated microgravity. Aerosp Med Hum Perform. 2017; 88(8):743–751.

INTRODUCTION: This study evaluated the use of statin therapy in U.S. Air Force (USAF) aviators with isolated hypercholesterolemia in terms of compliance with clinical practice guidelines (CPGs) and effectiveness in reducing low-density lipoprotein cholesterol (LDL-C) and coronary heart disease (CHD) risk.METHODS: This was a mixed design, 8-yr retrospective study that included 8185 participants with isolated hypercholesterolemia, of which 1458 (17.81%) were prescribed statin monotherapy.RESULTS: Overall agreement between CPG recommendations and patient-clinician decision makers was 0.920 (95% confidence interval: 0.955, 0.959) and 0.891 (95% confidence interval: 0.843, 0.851) per 2002 and 2013 CPGs, respectively. Overall agreement was primarily driven by the negative proportion of specific agreement; positive agreement was moderate for the 2002 CPG and poor for the 2013 CPG. LDL-C levels marginally decreased for all participants except non-CPG-recommended statin users per the 2002 CPG. CHD risk was minimally reduced for all participants per the 2002 CPG with the exception of CPG-recommended statin users, for whom risk increased; CHD risk decreased for CPG-recommended statin users, but increased for non-CPG-recommended statin users per the 2013 CPG. No one statin medication was found to be more clinically effective in reducing LDL-C or CHD risk, regardless of dose intensity.CONCLUSIONS: Aerospace medicine practitioners are following CPG recommendations for statin therapy. Statins provided minimal benefit, however, and CPG recommendations proved irrelevant in reducing LDL-C and CHD risk in this population of Air Force aviators. This result is attributable, in part, to the young age of the study cohort and the short follow-up period.Tvaryanas AP, Mahaney HJ, Schroeder VM, Maupin GM. Statin therapy in low-risk air force aviators with isolated hypercholesterolemia. Aerosp Med Hum Perform. 2017; 88(8):752–759.

INTRODUCTION: The purpose of the present study was to examine the influence of hypobaric hypoxia (HH) on a pilot’s flight performance during exposure to simulated altitudes of 91, 3048, and 4572 m (300, 10,000, and 15,000 ft) and to monitor the pilot’s physiological reactions.METHOD: In a single-blinded counter-balanced design, 12 male pilots were exposed to HH while flying in a flight simulator that had been placed in a hypobaric chamber. Flight performance of the pilots, pilot’s alertness level, S_po_2, heart rate (HR), minute ventilation (V_E), and breathing frequency (BF) were measured.RESULTS: A significant difference was found in Flight Profile Accuracy (FPA) between the three altitudes. Post hoc analysis showed no significant difference in performance between 91 m and 3048 m. A trend was observed at 4572 m, suggesting a decrease in flight performance at that altitude. Significantly lower alertness levels were observed at the start of the flight at 4572 m compared to 91 m, and at the end of the flight at 4572 m compared to the start at that altitude. S_po₂ and BF decreased, and HR increased significantly with altitude.DISCUSSION: The present study did not provide decisive evidence for a decrease in flight performance during exposure to simulated altitudes of 3048 and 4572 m. However, large interindividual variation in pilots’ flight performance combined with a gradual decrease in alertness levels observed in the present study puts into question the ability of pilots to safely fly an aircraft while exposed to these altitudes without supplemental oxygen.Steinman Y, van den Oord MHAH, Frings-Dresen MHW, Sluiter JK. Flight performance during exposure to acute hypobaric hypoxia. Aerosp Med Hum Perform. 2017; 88(8):760–767.

INTRODUCTION: There is much debate regarding the appropriate analgesic management of patients undergoing medical evacuation following combat trauma. Our primary objective was to review the utility of regional anesthetic techniques in patients undergoing aeromedical evacuation following surgical limb amputation as treatment for combat trauma.METHODS: This study was conducted as an observational retrospective cohort whereby acutely injured amputee patients were identified via the U.S. Transportation Command’s patient movement database. The Theater Medical Data Store was cross-referenced for additional patient care data including opioid consumption, duration of regional technique, pain scores, and rates of intubation.RESULTS: Eighty-four records were retrieved from the Theater Medical Data Store. All 84 patients were victims of improvised explosive device detonation requiring limb amputation and subsequent transport from Kandahar Airfield or Camp Bastion, Afghanistan, to the United States. The majority of interventions remained in place throughout the evacuation process. A significant decrease in opioid consumption in patients receiving regional anesthesia was identified at each leg of the medical evacuation process. Pain scores were sporadically reported and not statistically different. Higher rates of intubation were identified in the nonregional anesthetic group.DISCUSSION: Our analysis demonstrates the feasibility and effectiveness of applying regional anesthetic techniques for pain management to our combat wounded trauma patients throughout multiple stages of aeromedical evacuation. Benefits include the potential for less sedation and less opioid consumption while potentially foregoing the requirement for intubation during transport.Carness JM, Wilson MA, Lenart MJ, Smith DE, Dukes SF. Experiences with regional anesthesia for analgesia during prolonged aeromedical evacuation. Aerosp Med Hum Perform. 2017; 88(8):768–772.

INTRODUCTION: The American military is embarking on the ‘Third Offset’—a strategy designed to produce seismic shifts in the future of warfare. Central to the approach is the conjoining of humans, technology, and machines to deliver a decisive advantage on the battlefield. Because technology will spread rapidly and globally, tactical overmatch will occur when American operators possess a competitive edge in cognition. Investigation of cognitive enhancing therapeutics is not widely articulated as an adjunct to the Third Offset, yet failure to study promising agents could represent a strategic vulnerability. Because of its legacy of research into therapeutic agents to enhance human-machine interplay, the aerospace medical community represents a front-running candidate to perform this work. Notably, there are strong signals emanating from gambling, academic, and video-gaming enterprises that already-developed stimulants and other agents provide cognitive benefits. These agents should be studied not only for reasons of national security, but also because cognitive enhancement may be a necessary step in the evolution of humankind. To illustrate these points, this article will assert that: 1) the need to preserve and enhance physical and cognitive health will become more and more important over the next century; 2) aeromedical specialists are in a position to take the lead in the endeavor to enhance cognition; 3) signals of enhancement of the type useful to both military and medical efforts exist aplenty in today’s society; and 4) the aeromedical community should approach human enhancement research deliberately but carefully.Malish RG. The importance of the study of cognitive performance enhancement for U.S. national security. Aerosp Med Hum Perform. 2017; 88(8):773–778.

INTRODUCTION: Numerous authors have identified the stressors likely to be encountered on long duration space exploration missions (e.g., to Mars), including the possibility of significant crises, separation from family, boredom/monotony, and interpersonal conflict. Although many authors have noted that meaningful work may be beneficial for astronauts on these missions, none have detailed the sources of meaningful work for astronauts and how these sources may differ between astronauts. The present article identifies how engagement in meaningful work during long duration missions may mitigate the adverse effects of demands and increase the potential for benefits resulting from the missions.METHOD: Semistructured interviews were conducted with nine NASA personnel, including astronauts, flight directors, and flight surgeons. Questions addressed sources of meaning for astronauts, characteristics of tasks that enhance vs. detract from meaning, and recommendations for enhancing meaning.RESULTS: Personnel mentioned contributing to humanity and the next generation, contributing to the mission, and exploration as the most meaningful aspects of their work. Characteristics of tasks that enhanced meaning included using a variety of skills, feeling personal control over their schedule, autonomy in the execution of tasks, and understanding the importance of the experiments conducted on the mission. Top recommendations to sustain meaning were insuring social needs were met through such activities as the strategic use of social media, giving astronauts autonomy as well as structure, and conducting training during transit.DISCUSSION: Implications are addressed for tailoring meaning-based interventions for astronauts participating on long duration missions and assessing the effectiveness of these interventions.Britt TW, Sytine A, Brady A, Wilkes R, Pittman R, Jennings K, Goguen K. Enhancing the meaningfulness of work for astronauts on long duration space exploration missions. Aerosp Med Hum Perform. 2017; 88(8):779–783.

INTRODUCTION: Antarctica is a useful analog for spaceflight, as both environments are remote, isolated, and with limited resources. While previous studies have demonstrated increased asymptomatic viral shedding in both the Antarctic and spaceflight environments, clinical manifestations of reactivated viral disease have been less frequently identified. We sought to identify the incidence of clinical herpes zoster from viral reactivation in the Antarctic winter-over population.METHODS: Medical records from the 2014 winter season were reviewed for the incidence of zoster in U.S. Antarctic personnel and then compared to the age-matched U.S. population.RESULTS: Five cases of clinical herpes zoster occurred in the Antarctic Station population of 204 persons, for an incidence of 33.3 per 1000 person-years vs. 3.2 per 1000 person-years in the general population. Four cases were in persons under age 40, yielding an incidence of 106.7 per 1000 person-years in persons ages 30–39 compared to an incidence of 2.0 per 1000 person-years in the same U.S. age group.DISCUSSION: Immune suppression due to the stressful Antarctic environment may have contributed to the increased incidence of herpes zoster in U.S. Antarctic personnel during the winter of 2014. Working and living in isolated, confined, and extreme environments can cause immune suppression, reactivating latent viruses and increasing viral shedding and symptomatic disease. Such changes have been observed in other austere environments, including spaceflight, suggesting that clinical manifestations of viral reactivation may be seen in future spaceflight.Reyes DP, Brinley AA, Blue RS, Gruschkus SK, Allen AT, Parazynski SE. Clinical herpes zoster in Antarctica as a model for spaceflight. Aerosp Med Hum Perform. 2017; 88(8):784–788.

INTRODUCTION: Hypergravitational exposures during human centrifugation are known to provoke dysrhythmias, including sinus dysrhythmias/tachycardias, premature atrial/ventricular contractions, and even atrial fibrillations or flutter patterns. However, events are generally short-lived and resolve rapidly after cessation of acceleration. This case report describes a prolonged ectopic ventricular rhythm in response to high G exposure.CASE REPORT: A previously healthy 30-yr-old man voluntarily participated in centrifuge trials as a part of a larger study, experiencing a total of 7 centrifuge runs over 48 h. Day 1 consisted of two +G_z runs (peak +3.5 G_z, run 2) and two +G_x runs (peak +6.0 G_x, run 4). Day 2 consisted of three runs approximating suborbital spaceflight profiles (combined +G_x and +G_z). Hemodynamic data collected included blood pressure, heart rate, and continuous three-lead electrocardiogram. Following the final acceleration exposure of the last Day 2 run (peak +4.5 G_x and +4.0 G_z combined, resultant +6.0 G), during a period of idle resting centrifuge activity (resultant vector +1.4 G), the subject demonstrated a marked change in his three-lead electrocardiogram from normal sinus rhythm to a wide-complex ectopic ventricular rhythm at a rate of 91–95 bpm, consistent with an accelerated idioventricular rhythm (AIVR). This rhythm was sustained for 2 m, 24 s before reversion to normal sinus. The subject reported no adverse symptoms during this time.DISCUSSION: While prolonged, the dysrhythmia was asymptomatic and self-limited. AIVR is likely a physiological response to acceleration and can be managed conservatively. Vigilance is needed to ensure that AIVR is correctly distinguished from other, malignant rhythms to avoid inappropriate treatment and negative operational impacts.Suresh R, Blue RS, Mathers C, Castleberry TL, Vanderploeg JM. Sustained accelerated idioventricular rhythm in a centrifuge-simulated suborbital spaceflight. Aerosp Med Hum Perform. 2017; 88(8):789–793.

Brough B. You’re the flight surgeon: subependymoma. Aerosp Med Hum Perform. 2017; 88(8):794–796.

Harris Graessle CL. You’re the flight surgeon: coccidioidomycosis. Aerosp Med Hum Perform. 2017; 88(8):796–800.