Kiyoko Yokoyama* and Noriaki Kamiya
Graduate School of Design and Architecture, Nagoya City University, 2-1-10 Kitachikusa, Chikusa-ku, Nagoya 464-0083, Japan
*E-mail address: yokoyama@sda.nagoya-cu.ac.jp
(Received September 22, 2008; Accepted March 10, 2009)
Abstract. In the field of medical science, the invisible real forms of organs may be visualized using advanced technology. Few studies have visualized physiological condition in form. The purpose of this study is to visualize cardiac parasympathetic nervous activity in form. The power of high-frequency component of R-R interval time series derived from ECG (HF: 0.15-0.4 Hz) is an index of cardiac parasympathetic nervous activity. This index is visualized as a form. To realize real-time and continuous visualization of cardiac parasympathetic nervous activity, we developed a new method for calculation of HF power. The estimated accuracy of this method for calculating HF power was the same as in the conventional method. From an experiment comparing the various kinds of image, visualization using an apple with a facial expression was considered to have a related physiological and psychological relaxation effect.
Keywords: Heart Rate Variability, Cardiac Parasympathetic Nervous Activity, Power Spectrum Analysis, High Frequency Component, Visualization