Document Type


Date of Award

Winter 1-31-1994

Degree Name

Master of Science in Electrical Engineering - (M.S.)


Electrical and Computer Engineering

First Advisor

Stanley S. Reisman

Second Advisor

Walter N. Tapp

Third Advisor

Peter Engler


Heart rate variability regulation is controlled by the autonomic nervous system. Disorders of the autonomic nervous system may cause the loss of heart rate variability. Two new approaches, correlation dimension and entropy, based on ideas from nonlinear dynamics, have been applied to studying heart rate variability. The correlation dimension measures the extent of correlation between the data points. The entropy measures the amount of information needed to specify the state of a system. The interbeat interval signal (1BI) from eighteen subjects (nine normal controls and nine patients with Chronic Fatigue Syndrome (CFS) ) have been analyzed and compared. The results show that the CFS patients have higher correlation dimension and lower entropy than normal subjects, which indicates that the heart rate variability is reduced for these patients. This suggests that there may be an autonomic nervous system imbalance in CFS patients.



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