Detrended Fluctuation Analysis: An Experiment About the Neural-Regulation of the Heart and Motor Vibration

Acceleratory and inhibitory cardio-regulator nerves innervate the heart of a living creature. The two nerves discharge concurrently to maintain an equilibrium state of the heart. The nerves change their frequency of discharge in a reflexive manner to meet the demand from the periphery, such as augmentation of oxygen supply or vice versa. Consequently, the heart exhibits a dynamic change in rate of pumping and force of contraction. If the control system fails, the heart exhibits an unhealthy state. However, an assessment of a healthy/unhealthy status is uneasy, because we are not able to monitor the nerve activities by non-invasive methods. Therefore, we challenged to detect a state of the heart without nerve-recordings. We used the Detrended Fluctuation Analysis (DFA) by applying it to a heartbeat interval time series because the DFA is believed that it can quantify the state of heart. The objective of this research was to determine whether the DFA technology could function as a useful method for the evaluation of the subject’s quality of a cardiovascular-related illness. We performed DFA on the EKGs (Electrocardiograms) from living organisms and a running motor as well. We conclude that scaling exponents could determine whether the subjects are under sick or healthy conditions.