training content, team membership stability, and team size moderate the effectiveness of team training interventions. One function of this training is to establish a common operational culture that shares the same vernacular, reinforces team bonds, and establishes shared goals for performance and safety.

Finally, perhaps the least tangible aspect of training addresses the meta-cognitive, or executive, functions that astronauts must perform as part of their “cognitive control” while under stress. In their study of stress and human performance, Salas, Driskell, and Hughes define stress as the process by which certain environmental demands evoke an appraisal process in which perceived demand exceeds resources, and the result is undesirable psychological, physiological, or behavioral outcomes; for example, stress-related failures of decision making have been attributed to nearly half of fatal aviation accidents.2 At a basic level, training for cognitive control and effective stress response is related to the development of executive functions that guide selective attention to appropriate aspects of the environment—such as pilots learning, when disoriented, to focus on a visual scan of flight instruments despite conflicting vestibular sensations. At a more holistic level, an expert is able to plan and pattern activities to avoid “cognitive lockup,” to manage tasks effectively within given demands and resources, and to recognize effective decision-making strategies to apply to different types of situations.

Recent research suggests that three elements must be considered in training for effective cognitive control (including decision making) under stress. First, such training is most effective when the trainees enter actual operations with the perception that they are well prepared. Second, training theories suggest that the trainee should be trained on tasks and situations similar to those that will be experienced under stress, an effect referred to in the military as “train how you fight.” Third, training for stressful tasks requires a stressful training environment.

The need for a stressful, operationally realistic training environment is also recognized operationally by safety-critical domains. For example, although commercial aviation often certifies its pilots on the basis of training in simulators alone, this industry also recognizes the need for a newly minted pilot then to fly real operations with a more experienced pilot for a significant portion of time as the new pilot develops further experience with the real operational environment.

Similarly, while military training increasingly uses simulators, live-fire exercises remain a vital component of training. For example, a review of the significant losses experienced by flight pilots in their first experiences of real combat motivated the ongoing U.S. Air Force Red Flag exercises, which re-create as realistically as possible the actual stresses of the real flight environment. Similarly, training for naval nuclear operations, for example, progresses from classroom and part-task simulator instruction through the training on actual nuclear power plants dedicated to training and providing the same hazards as those of real plants.

If one determines that a stressful training environment is necessary, in which environment should astronaut training be conducted? Historically, the operational culture of the Astronaut Corps has been centered on aviation, including its attention to safety and its valuing of teamwork and calm, systematic responses to emergencies. Bearing in mind that changing an operational culture is difficult and that the period of transition is a risk factor during which common safety nets within the organization are stressed, changing the Astronaut Corps training basis from aviation would be a significant, risky endeavor that should only be undertaken when there is a compelling reason.

Thus, the ideal training for the Astronaut Corps should be designed to integrate instructional content, instructional method, and training resources systematically and purposefully in a phased progression from classroom instruction, through simple procedural trainers (part-task simulators, mock-ups), through high-fidelity simulators, and ultimately into stressful training environments that foster an effective operational culture and which require response to stresses like those that may be experienced in spaceflight. For an Astronaut Corps using aviation as its shared operational experience, this ideal training environment would then include procedural trainers and simulators of spacecraft, and then, because the spacecraft are themselves unavailable for training, a transition to aviation environments that mirror the time pressure and physical stressors of spaceflight, including the discomforts of specialized suits, helmets, oxygen masks, and life-critical environmental support systems.

Even though ideal, such a full range of low- and high-fidelity simulators and aircraft as noted in the ultimate


2 E. Salas, J.E. Driskell, and S. Hughes, Introduction: The study of stress and human performance, pp. 1-45 in Stress and Human Performance(E. Salas, and J.E. Driskell, eds.), Lawrence Erlbaum Associates, Inc., Mahwah, N.J., 1996.

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