Principal Investigator:

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Development of an Index of Habitability Using
Converging Indicators
Principal Investigator Patricia Cowings, Ph.D.
NASA ARC Coinvestigators William
Toscano, Ph.D. NASA ARC Charles DeRoshia,
M.S. NASA ARC Bruce Taylor, Ph.D. University
of Akron Seleimeh Hines, Ph.D. NRC Post
Doctoral Fellow
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Primary Mission Goal of Space Human Factors

• Enable a permanent human presence in space
• Develop protocols to
• Accurately assess spaceflight effects on crew
  health, safety, and operational performance.
• Evaluate and test countermeasures that will
  remedy these environmental effects.

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Technical Background

• Extended spaceflight affects physiology with
  associated adverse effects on crew performance
  and health.
• Other factors like workload, isolation, fatigue,
  etc. are known to effect operational efficiency.
• There is a wide range in the ability of
  individuals to adapt to space and re-adapt to
  Earth.
• Future crew complementsmen and women,
  multi-cultural, different professional
  backgrounds and physical condition.

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Statement of Problem

• Methods are needed
• to examine individual differences in the
  environmental effects of extended spaceflight on
  crew.
• to evaluate the efficacy of countermeasures for
  individuals.

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Psychophysiological Research Laboratory

• Research program includes
• Motion sickness in space and on Earth
• Post-flight orthostatic intolerance
• Performance during chronic and acute stress
• Neurobehavioral/psychosocial function

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Psychophysiological Research Laboratory

• Method of Assessment Converging Indicators
• Physiological measures
• Performance metrics
• Standardized self-report scales
• Method of Correction Preflight Training
• Autogenic-Feedback Training Exercise (AFTE)
• 6-hour physiological conditioning program

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Converging Indicators
Physiology (ANS, CNS)
Subjective States (mood, symptoms)
Performance (cognitive, perceptual, neuro-motor)
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Autogenic Feedback System-2
Physiological Measures
skin temperature finger blood volume pulse
skin conductance heart rate respiration rate
Reported Symptoms
warmth dizziness headache drowsiness salivation pa
llor sweating nausea vomiting
Autogenic-Feeback System-2 (AFS-2)
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Mood Scale and Delta Performance Battery
Reported Mood States Performance Subtests

• code substitution
• spatial transformation
• non-preferred hand tapping
• preferred hand tapping
• pattern comparison
• three-choice reaction time
• grammatical reasoning

• motivation to perform
• arousal state
• fatigue level
• ease of concentration
• physiological tension
• elation
• physical discomfort
• contentedness

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Approach

• Database analyses and archival.
• Develop signal analysis and processing software.
• Test converging indicators methods in operational
  environments.

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Habitability in Rotating Centrifuge
22 hour exposures at G-levels up to 1.5 G
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Individual Differences in Adaptational Capacity

• Four adult men participated in this study
• Each subject lived aboard the centrifuge for 22
  hours at 1.0g (i.e., no rotation), and 1.25 g.
• One subject also participated in a 1.5g test

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Individual Differences in Adaptational Capacity

• Ambulatory physiological data were collected
  continuously.

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Individual Differences in Adaptational Capacity

• Subjects occupied a small compartment, equipped
  with bed, video entertainment, laptop computer,
  toilet facilities and food and beverages.

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Individual Differences in Adaptational Capacity

• Subjects were in video and voice contact with
  investigators and medical monitors at all times.

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Individual Differences in Adaptational Capacity

• G-tolerance tests were administered before and
  after each 22 hour habitat test.
• G-load was increased until subjects experienced
  reduced peripheral vision and/or pre-syncope.

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Individual Differences in Adaptational Capacity

• Subjects were required to perform a stand test
  at 4-hour intervals to evaluate their orthostatic
  tolerance.

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Individual Differences in Adaptational Capacity

• Performance tests and a mood state scale were
  performed on a laptop computer following each
  stand test, and symptom reports were obtained
  verbally.

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Stand Tests at 1.0g Heart Rate and Blood Pressure
Subject Q22
Subject Q23
Subject Q20
Subject Q21
Time of Day
Time of Day
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Stand Tests at 1.25g Heart Rate and Blood Pressure
Subject Q21
Subject Q23
Subject Q20
Subject Q22
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Blood Pressure and Heart Rate of Subject Q20
During Hyper-g

• As g-load increased, this subject showed both
  increases in heart rate and diastolic blood
  pressure which enabled cardiac output to
  stabilize.
• Although his autonomic profile protected him
  from syncope, he was more susceptible to motion
  sickness than others.

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Cardiac Responses to G-Tolerance Tests
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Cardiac Responses During Stand Tests at 1.25g
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Converging Indicators for Subject Q20 at
Different G-loads
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Converging Indicators for Subject Q23 at
Different G-loads
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Conclusions

• Converging indicators can be used to identify
  individual differences in adaptational capacity
  (e.g., susceptibility to orthostatic intolerance
  and motion sickness).
• Psychomotor performance was significantly
  degraded during hypergravity. Symptoms generally
  increased with g-load. Reductions of mood,
  perceptual or cognitive responses were highly
  idiosyncratic.
• Physiological profiles may be used to predict how
  well individuals adapt and suggest that training
  control of autonomic responses (i.e.,
  Autogenic-Feedback Training Exercise-AFTE) may
  help to reduce or eliminate symptoms.