Regulatory changes at high altitudes in comparison with post-space-flight reactions

Area of Science:

• Psychophysiology
• Space Medicine
• Environmental Physiology

Background:

• The "Assessment of Autonomic Outlet Type" (AOT) is a psychophysiological method.
• Previous studies established distinct autonomic nervous system (ANS) and cardiovascular system (CVS) reaction patterns in different cohorts.
• These patterns were correlated with non-responders, voice-responders, heart-responders, rheumatic diseases, and hypertensives.

Purpose of the Study:

• To compare the application of the AOT method in space and high-altitude environments.
• To determine if the AOT method can differentiate subject responses to varying environmental stressors.
• To classify complex regulatory patterns of the ANS and CVS in response to psychological stressors.

Main Methods:

• Application of the AOT psychophysiological method.
• Cluster analysis to identify distinct reaction patterns.
• Discriminant function analysis for classification of regulatory patterns.
• Comparison of data from cosmonauts and terrestrial experiments at 3600m.

Main Results:

• Cluster analysis revealed distinct reaction patterns correlating with specific control and patient groups.
• The AOT method, using a discriminant function, successfully classifies complex ANS and CVS regulatory reactions.
• Ongoing application since 1997 with Russian cosmonauts provides continuous data.
• Terrestrial experiments at 3600m altitude serve as a comparative baseline.

Conclusions:

• The AOT method is capable of differentiating subject responses to environmental stressors like space and high altitudes.
• The method provides a reliable classification of autonomic and cardiovascular regulatory responses to psychological stressors.
• Findings support the utility of the AOT method in monitoring physiological adaptation in extreme environments.