PRINCIPAL INVESTIGATOR(S ): J. Hanley, and W. Ross Adey 



EXPERIMENT TITLE/NUMBER : Sleep and Wake States in the Biosatellite III 



Monkey: Visual and Computer Analysis of Telemetered 

 Electroencephalographic Data from Earth Orbital 

 Flight 



PROGRAM/ MISSION : Biosatellite III 



CLASSIFICATION : Animal - Pig-tailed monkey ( Macaca nemestrina ) 



DISCIPLINE(S) : Chronobiology, Neurosensory 



OBJECTIVES : To study the sleep and wake states in a complex mammalian system 

 in a weightless environment. 



PROTOCOL : Ten EEG, two EOG and two EMG channels were monitored. Data was 

 telemetered to earth tracking stations at the rate of 22.4 kilobits/sec, and 

 collected every 97 minutes. The monkey was acclimated to 12 hour day and 12 

 hour night cycle in the capsule. 



EQUIPMENT : EEG, EOG and EMG, electrodes. 



RESULTS : There were rapid transitions in state, brevity of state, and unusual 

 transitions from one state to another. The monkey never achieved its normal 

 terrestrial cycle. There was a dramatic reduction in REM and Stage 4 sleep. 

 Eye movements, normally seen only in REM, were observed during State II and IV 

 sleep. Eye movements decreased with increasing flight time, and ceased by 

 orbit 126, accompanied by a change in EEG. None of the controls displayed 

 this phenomenon. 



CONCLUSIONS : The biological signals studied for correleates of the sleep and 

 wake states of the primate were drastically affected by the weightless state. 

 EEG, EOG, and EMG were all markedly disrupted by the zero gravity conditions. 

 Moreover, the changes began concurrently with the onset of weightlessness and 

 were not secondary to altered fluid balance or body temperature. There was a 

 complex response to the independent variable of weightlessness, with a sudden 

 decline on day 8 attributable to fluid loss and redistribution of blood in the 

 thorax consequent to the zero gravity state. 



PUBLICATIONS : 6, 241 



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