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Biomedical subjects

P A Santy

Publications and source records attributed to P A Santy.

At least 19 recordsLinked to original sources
PubMed1996

The use of IQ assessment in astronaut screening and evaluation.

BACKGROUND: The screening and evaluation of astronaut candidates usually includes measures of cognitive and intellectual capacity. Questions of ceiling effects and discriminability when evaluating individuals assumed to be of above average intelligence should be considered. The current study examines ceiling effects and discriminability on IQ assessment between pilots vs. mission specialists and men vs. women in the selection of astronaut candidates. METHODS: IQ scores on 104 male and female Shuttle astronaut candidates as measured by the Multidimensional Aptitude Battery (MAB) were analyzed via factor analyses and tests of differences between genders, selection status, and job types. Total group, gender, and job type specificity and sensitivity and overall percent correctly classified were assessed on selected vs. unselected classification. RESULTS: Exploratory and confirmatory factor analyses failed to replicate the proposed factor configuration prompting reconfigured domain scores. Analyses of differences between gender, selection, and job categories found different results when using reconfigured IQ scores compared to the original formulation. The 10 subscales performed better than overall domain scores in sensitivity, specificity, and as significant predictors of individuals selected. Both versions of Verbal, Performance, and Full Scale IQ scores performed similarly regarding sensitivity and specificity. The reconfigured scores were better predictors of selection. DISCUSSION: Evidence for sensitivity, specificity, and classification prediction was better for subscales than overall domain scores. Some consideration to using reconfigured domain scores should be given to increase instrument utility.

Aptitude Tests↗
PubMed1994

Teaching clinical psychopharmacology on an inpatient psychiatric research center.

In this article we have shown how an inpatient Psychiatric Clinical Research Center has been used successfully to teach medical students and residents some basic principles of clinical psychopharmacology. Although teaching effectiveness and resident acceptance of the program have not been measured objectively (we intend to do this in the next 2 years), informal feedback about the CRC rotation has been enthusiastic. The clinical psychopharmacology curriculum in our department has been enhanced by the experience of trainees on a research unit. In the rapidly expanding area of psychopharmacology, where new drugs are continually coming on the market, the CRC provides an opportunity to demonstrate the biopsychosocial model and to explore the interface between the research and clinical aspects of psychopharmacology.

Academies and Institutes↗
PubMed1994

Strategies for the preflight circadian shifting of Space Shuttle crews.

In June, 1990, a workshop was put together at NASA/Johnson Space Center to address difficulties the astronauts were having in adjusting their wake and sleep schedule, both immediately before and during Space Shuttle missions. The workshop members, prominent investigators in human circadian research, developed a number of strategies by which astronauts could tackle the problem of circadian adaptation within the demanding timetable of a Space Shuttle mission. The strategies included both abrupt and gradual methods, and some approaches used artificial "very bright lights" to reset the physiologic circadian pacemaker. The strategies have since been operationally implemented on Space Shuttle flights, with good success. This is a report of the problems addressed by the workshop and its recommendations.

Adaptation, Physiological↗
PubMed1994

An overview of international issues in astronaut psychological selection.

The NASA Johnson Space Center Medical Sciences Division convened an In-House Working Group on Psychiatric and Psychological Selection of Astronauts in 1988. Working with the European Space Agency (ESA) and the National Space Development Agency (NASDA) of Japan, psychiatrists and psychologists experienced in selecting individuals for training as astronauts or analogous duties studied the development of appropriate criteria. Psychiatric criteria generally concern the detection of pathological conditions, and thus "select-out" applicants by disqualification. Psychological criteria may be used to identify specific affirmative criteria that make an individual particularly well-qualified for such duties, and thus concern "select-in" processes for operational crews. As space missions grow longer, and as crews become larger and more demographically diversified, the long-ignored questions, "What sort of healthy individuals should be selected for such missions," and "How do we know this?" will become more critical to the success of space exploration. The papers included in this Panel concern the results of these investigations, and represent long-needed quantification of these two selection processes, select-out and select-in, in several cultures.

Astronauts↗
PubMed1993

Results of a structured psychiatric interview to evaluate NASA astronaut candidates.

One hundred six astronaut applicants who had passed initial screening were evaluated for Axis I and Axis II DSM-III-R diagnoses using a structured psychiatric interview. Nine of 106 candidates (8.5%) met diagnostic criteria for six Axis I (including V-code), or Axis II disorders. The use of the NASA structured interview was effective in identifying past and present psychopathology in a group of highly motivated and healthy astronaut applicants. This was the first time that a structured interview had been used in such a setting for this purpose. The methodology described is applicable to any situation where the presence or history of psychopathology requires evaluation for job selection (e.g. pilot selection).

Aerospace Medicine↗
PubMed1993

Multicultural factors in the space environment: results of an international shuttle crew debrief.

There is increasing interest and concern about the multicultural and multinational factors which might negatively affect adjustment and performance of Space Station Freedom (SSF) crews, living and working for long periods of time in the space environment. To begin identifying potential problem areas, a crew debrief questionnaire (called an "International Crew Debrief") was mailed to U.S. astronauts who flew on Shuttle missions between 1981-1990 with one or more crewmembers from other countries. There were 20 U.S. astronauts who flew on international space missions; 9 of these responded to the questionnaire, for a return rate of 45%. There were 42 incidents reported: 9 in the preflight period; 26 inflight; and 7 in the postflight period. Most of these incidents were rated as having a low or medium impact, but five of the inflight incidents were rated to have a "high" mission impact. A number of causes for the problems were listed, and are discussed. Debrief respondents provided useful and timely recommendations on preflight training which may help facilitate the integration of multinational crews, and prevent multicultural or multinational factors from interfering with mission operations.

Cultural Characteristics↗
PubMed1992

Human reproductive issues in space.

Animal studies in space or analogous environments have suggested that there may be problems in the reproductive sphere; such factors might limit mankind's ability to live and work for extended periods of time in microgravity or on non-terrestrial planetary surfaces. A review of reproductive functioning in animal species studied during space flight demonstrated that most species were affected significantly by the absence of gravity and/or the presence of radiation. These two factors induced alterations in normal reproductive functioning independently of, as well as in combination with, each other. Based on animal models, we have identified several potential problem areas regarding human reproductive physiology and functioning in the space environment. While there are no current space flight investigations, the animal studies suggest priorities for future research in human reproduction. Such studies will be critical for the successful colonization of the space frontier.

Animals↗
PubMed1991

Pharmacologic considerations for Shuttle astronauts.

Medication usage by crewmembers in the preflight and inflight mission periods is common in the Shuttle Program. The most common medical reports for which medication is used are: space motion sickness (SMS), sleeplessness, headache, and backache. A number of medications are available in the Shuttle Medical Kit to treat these problems. Currently, astronauts test all frequently used medications before mission assignment to identify potential side-effects, problems related to performance, personal likes/dislikes, and individual therapeutic effect. However, microgravity-induced changes in drug pharmacokinetics, in combination with multiple operational factors, may significantly alter crew-member responses inflight. This article discusses those factors that may impact pharmacologic efficacy during Shuttle missions.

Aerospace Medicine↗
PubMed1991

Psychiatric diagnoses in a group of astronaut applicants.

Between 1959 and 1987, the psychiatric evaluation of astronaut candidates evolved from a 30-h intensive examination evaluating applicants for psychopathology, and studying their performance under stress, to a 2-h clinical interview whose structure and contents were determined by the individual examiner. Evaluations done during these years applied both psychiatric (or, "select-out") criteria and psychological (or, "select-in") criteria. In an attempt to more rigorously define the psychiatric, "select-out" component, a standardized, semi-structured clinical interview was developed to identify the presence or history of psychiatric disorders listed in the Diagnostic and Statistical Manual of Mental Disorders, 3rd Ed. ("DSM-III"). A total of 117 astronaut applicants underwent this clinical interview as part of a comprehensive medical evaluation during a recent astronaut selection. Of the 117 applicants, 9 (7.7%) met DSM-III criteria for a variety of Axis I and Axis II diagnoses, including V-code diagnoses.

Aerospace Medicine↗
PubMed1990

Reproduction in the space environment: Part I. Animal reproductive studies.

Mankind's exploration and colonization of the frontier of space will ultimately depend on men's and women's ability to live, work, and reproduce in the space environment. This paper reviews animal studies, from microorganisms to mammals, done in space or under space-simulated conditions, which identify some of the key areas which might interfere with human reproductive physiology and/or embryonic development. Those space environmental factors which impacted almost all species included: microgravity, artificial gravity, radiation, and closed life support systems. These factors may act independently and in combination to produce their effects. To date, there have been no studies which have looked at the entire process of reproduction in any animal species. This type of investigation will be critical in understanding and preventing the problems which will affect human reproduction. Part II will discuss these problems directly as they relate to human physiology.

Animals↗
PubMed1990

Reproduction in the space environment: Part II. Concerns for human reproduction.

Long-duration space flight and eventual colonization of our solar system will require successful control of reproductive function and a thorough understanding of factors unique to space flight and their impact on gynecologic and obstetric parameters. Part II of this paper examines the specific environmental factors associated with space flight and the implications for human reproduction. Space environmental hazards discussed include radiation, alteration in atmospheric pressure and breathing gas partial pressures, prolonged toxicological exposure, and microgravity. The effects of countermeasures necessary to reduce cardiovascular deconditioning, calcium loss, muscle wasting, and neurovestibular problems are also considered. In addition, the impact of microgravity on male fertility and gamete quality is explored. Due to current constraints, human pregnancy is now contraindicated for space flight. However, a program to explore effective countermeasures to current constraints and develop the required health care delivery capability for extended-duration space flight is suggested. A program of Earth- and space-based research to provide further answers to reproductive questions is suggested.

Extraterrestrial Environment↗
PubMed1988

Analysis of sleep on Shuttle missions.

Many aspects of Shuttle missions may have significant impact on the normal sleeping patterns of crewmembers. Using a standard debriefing form, 58 crewmembers from 9 Shuttle flights (6 single-shift flights, and 3 dual-shift flights) were debriefed within 3 d postflight. Specific questions on the form relating to sleep quality and quantity, fatigue, and sleep medication usage during all flight phases were analyzed. Of crewmembers on dual-shift missions 50% (11 of 22) used sleep medications at least once inflight compared to 19.4% (7 of 36) of single-shift. The biggest impact on normal sleep patterns occurred during the first and last days of a mission, with averages of 5.7 h and 5.6 h, respectively. These results suggest that sleep disruption is a common occurrence on Shuttle missions. Further studies are suggested to develop strategies for coping with this potential problem.

Circadian Rhythm↗
PubMed1988

Space motion sickness during 24 flights of the space shuttle.

The incidence and severity of Space Motion Sickness (SMS) were determined from 24 flights of the Space Shuttle. A standardized questionnaire developed at the NASA-Johnson Space Center (JSC) was administered to all crewmembers postflight during an oral debriefing with the examining flight surgeon. Cases of SMS were graded mild, moderate or severe using criteria developed at the JSC. The incidence of SMS during a first Shuttle flight for 85 crewmembers was 67% (57 cases). There were 26 mild cases (30%), 20 moderate (24%), and 11 severe (13%). Differences were found between males and females, crew positions (Commander, Pilot, Mission Specialist, etc.), and age groups, which were not statistically significant (p greater than 0.05), but would suggest future research into the mechanism, prevention, and treatment of SMS. The 26 crewmembers with a second flight showed a reduction in SMS incidence to 46%, but the change was not significant compared with the first flight. Nine crewmembers (35%) showed a reduction in SMS severity comparing first and second flights, yet there was no significant difference in the mean time between flights for crewmembers with SMS versus asymptomatic crewmembers. Variability in crewmember training and flight experience may explain some of the differences observed.

Adult↗
PubMed1988

Comparison of aerobic fitness and space motion sickness during the shuttle program.

Space motion sickness (SMS) is an important problem for short duration space flight and 71% of STS crewmembers develop symptoms. The search for effective countermeasures and factors that correlate with sensitivity has been extensive. Recently, several investigators have linked aerobic fitness with motion sickness sensitivity in the 1-G or high-G environment. This paper compares the aerobic fitness of 125 Shuttle crewmembers with their SMS symptom category. Aerobic fitness data were obtained from the exercise tolerance test (ETT) conducted nearest the time of launch. SMS data were derived from the medical debrief summaries. Mean VO2max for crewmembers in four SMS categories (none, mild, moderate, severe) were 44.55, 44.08, 46.5, and 44.24 ml.kg-1.min-1, respectively. Scattergrams with linear regression analysis comparing aerobic fitness and SMS symptom classification are also presented. Correlation coefficients comparing SMS categories vs. aerobic fitness for men and women reveal no definite relationship between the two factors. Due to the subjective nature of the data, further studies are suggested to corroborate these findings.

Female↗
PubMed1987

Psychiatric components of a health maintenance facility (HMF) on Space Station.

The operation of a permanently manned space station brings a special challenge to psychiatry due to the combined physiological, emotional, and social stresses which will affect its occupants. Psychiatric diagnostic and therapeutic techniques will be a part of the Space Station's general medical support, known as the Health Maintenance Facility (HMF). The psychiatric component of HMF will promote psychological health throughout the mission and permit treatment, if necessary, of those psychiatric disorders which could impact mission success. This paper will discuss these emotional disorders and propose methods of management in the microgravity environment.

Adjustment Disorders↗
PubMed1983

Undiagnosed myasthenia gravis in emergency psychiatric referrals.

The diagnosis of myasthenia gravis is difficult to make in the emergency department. Reported are two cases in which myasthenia was not suspected and the patients were referred to the emergency psychiatrist. In both cases, when appropriate medical treatment was instituted, the psychological symptoms disappeared.

Adult↗