Abstract: Methods of isolating individual neural impulses are disclosed. In a preferred embodiment, methods of observing the response of the heart to autonomic neural control are presented. The present invention is used to observe cardioventilatory phase-locking. The noninvasive technique disclosed are a useful clinical tool for observing phase locking as diagnostic of physiological disorders which result from autonomic neural dysfunction. The methods of observation disclosed also are applicable to the isolation of other neural impulses. An understanding of cardioventilatory interaction is obtained by plotting highly accurate heartbeat-interval (hbi) time series data versus ventilator phase. The data displays created by the methods of the present invention show structure whose features are reproducible over time and across subjects. These structures are attributable to the effect of individual neural impulses from the autonomic nervous system which influence the cardiac pacemaker.

Abstract: A method of converting apparently chaotic time series data to a visual texture which, when displayed, can be really analyzed empirically. Correlation plots of vectors derived from time series of heartbeat intervals are displayed in color, to reveal useful information. The invention is particularly useful in a hospital cardiac environment, where subtle changes in cardiac rhythm can, with the method of this invention, provide evidence of abnormal cardiac functions.