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NASA NTRS · 20040089154

Transfer function analysis of the autonomic response to respiratory activity during random interval breathing

Chen, M. H.·Berger, R. D.·Saul, J. P.·Stevenson, K.·Cohen, R. J.
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Abstract

We report a new method for the noninvasive characterization of the frequency response of the autonomic nervous system (ANS) in mediating fluctuations in heart rate (HR). The approach entails computation of the transfer function magnitude and phase between instantaneous lung volume and HR. Broad band fluctuations in lung volume were initiated when subjects breathed on cue to a sequence of beeps spaced randomly in time. We studied 10 subjects in both supine and standing positions. The transfer function, averaged among all the subjects, showed systematic differences between the two postures, reflecting the differing frequency responses of the sympathetic and parasympathetic divisions of the ANS.

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Non-NASA CenterNASA Discipline CardiopulmonaryPosture/physiologyHeart Rate/physiologyRespiratory PhysiologyAutonomic Nervous System/physiologySignal Processing, Computer-AssistedMaleLung Volume MeasurementsFemaleSupine Position/physiologyAdultSupport, U.S. Gov't, Non-P.H.SSupport, Non-U.S. Gov'tComparative StudyHumanElectrocardiography

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Chen, M. H., Berger, R. D., Saul, J. P., Stevenson, K., Cohen, R. J.. 1987-01-01. Transfer function analysis of the autonomic response to respiratory activity during random interval breathing. https://ntrs.nasa.gov/citations/20040089154

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