Temporal variations in the pattern of breathing.
Bruce, Eugene N.
Center for Biomedical Engineering, University of Kentucky,
Lexington, KY 40506
APStracts 3:0022A, 1996.
Breath to breath variations in the pattern of breathing can occur as
uncorrelated random variations ("white noise"), correlated
random changes, or as one of two types of nonrandom variations:
periodic oscillations, or nonrandom nonperiodic fluctuations. White
noise is probably present in all physiological processes. In many
cases periodic variations are due to oscillations originating in
chemoreflex feedback loops. It has long been hypothesized that
correlated random variations in breathing pattern are due to central
neural "memory" mechanisms, but part of this behavior might
be due to chemoreflex mechanisms. Recently it has been concluded that
nonlinear interactions between pulmonary and airway afferent
activities and integrative central respiratory mechanisms can produce
nonrandom nonperiodic (and also periodic) variability of the
respiratory pattern. These latter studies have provided new insights
about the behavioral relevance of the integrative character of
central respiratory mechanisms and the time-varying nature of
pulmonary afferent activities, and have emphasized the importance of
identifying the physiological bases for these phenomena. These and
other findings are interpreted assuming that respiratory rhythm
generation/pattern formation occurs via a nonlinear oscillator and
novel inferences concerning temporal variations of the breathing
pattern are proposed.
Received 1 June 1995; accepted in final form 12 December 1995.
APS Manuscript Number A1361-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 22 January 96