A brief review of some apparent similarities between life at an Antarctic station during the winter and longterm space flight is presented. Both environments are novel and unique, and involve potential danger from both individual accidents and the failure of life support systems. Once established, the daily routine in both may become monotonous. However, due to the nature of these environments individuals may be required to suddenly shift, from a state of boredom into their highest level of physical and mental activity to cope with an emergency. A certain type of individual is required to successfully meet these requirements to remain alert to potential hazards over an extended period of time and to maintain psychological adaptability under the influence of environmental stressors. Life in a high-risk environment requires an individual with psychological strength, an ability to learn quickly under unexpected conditions, tolerance for loneliness and anxiety, and an excellently functioning central nervous system.

The type of individual required is defined as being adaptively competent. Adaptive competence is the ability to cope with immediate changes in the environment and to adjust to long-term changes while maintaining effective performance and continuing psychological growth. Competence is a relatively new concept which is defined in terms of personal characteristics such as cognitive style, knowledge, 26skills, attitudes, etc., that facilitate achievements having adaptive value in interactions with the environment. Competence is a consequence of learning and appears to derive primarily from the socialization process that develops the social-self. The end product, for the psychologically adaptive individual, is a lifestyle that provides satisfactorily for physical, emotional, cognitive, and philosophical needs within a socially productive context. Personal developmental history, future-self attitudes, stress testing, and peer evaluations appear to be the best methods now available for assessing competence. Assessments based upon evaluations of neuropsychological functioning related to developmental history may provide more objective measures in the future.

In terms of future directions for assessment it is suggested that measurements of functional lateral differentiation in the nervous system may be useful in testing neural efficiency as well as in providing an index of adaptive ability. It should be emphasized that much of the information concerning functional lateralization in the nervous system and its potential for predicting behavior is still highly speculative. Reliable techniques for the assessment of this aspect of neural functioning that can be used in an applied setting with normal individuals remain to be developed. Nevertheless, lateralization appears to be an important area for future work because the evidence available suggests that this functional feature of the nervous system may be directly related to the individual's past experience. Biographical background or past experience histories have consistently demonstrated a substantial relationship to valid predictions of future performance (1, 2, 3, 4, 5, 6). But comprehensive histories containing significant events in an individual's life are difficult to obtain and may require multiple interviews over an extended period of time. This procedure is often not practical. If assessment of functional lateralization can provide an objective measure of the influence of the individual's developmental history on his or her brain, it will provide an extremely useful tool for the prediction of behavior.

However, it should be noted that at this time it is difficult to assume that enough is known about the nature of cerebral functional specialization to choose an hypothesized right or left hemisphere task that will have high validity for all individuals who might be tested. Tasks oriented toward the function of a given hemisphere may also obscure the presence of a strong hemispheric bias or dispositional lateralization gradient. Therefore, the primary assessment criterion for lateralization should be essentially 27equivalent performance in both hemispheres on the same type of task. It is expected that symmetrical performance will indicate well-integrated intrahemispheric functional structures. Measurement of bilateral symmetry in performance is a standard technique in neuropsychological assessment (7, 8, 9), which appears to be more important at this stage of knowledge of the mechanisms of cerebral functions and interhemispheric interactions. Too much emphasis has been placed upon the uniqueness of the two hemispheres of the human brain, while too little is known concerning interactions between them. The quality of the neural mechanisms and their level of efficiency within each hemisphere and how these factors influence behavior appear to be more important than the recently demonstrated differences that are now so prominent in the literature (10). Future research in this area needs to be addressed to evaluating the functional significance of interhemispheric interactions.

Both adaptive and nonadaptive individuals are attracted to high-risk environments. Developmental studies suggest that both types of individuals may change. Therefore, a reassessment program is essential. Again, the development of techniques for evaluating neural functioning appears to offer one solution for the problem of periodic reassessment. However, psychometric measures for assessing crew compatibility factors are also essential. The presence of socially nonadaptive crewmembers in a closed, isolated group can significantly decrease the group's efficiency. Problems of cultural drift away from and hostility toward the supporting society may also be increased by the presence of socially nonadaptive individuals. To limit these problems, crew-members should be dedicated professionals, time in isolation should be limited, and support personnel should be veterans of the isolated experience. Antarctic veterans may provide a useful pool of potential volunteers for initial development activities in space. The most efficient method for handling tasks of selection, training, isolated duty, and support may be to have a formal occupational organization in which individuals are rotated through duty in these various phases of the operation during an extended career commitment. Additional research in all aspects of assessment is required to assure the selection of those individuals who will be most likely to complete their mission safely and in good health.