2019 年 17 巻 2 号 p. 59-66
We examined the relationship between the activity of the dorsolateral prefrontal cortex (DLPFC) and heart rate variability (HRV) component after practice of yogic breathing ‘Kapalabhati’ (KB) with a tempo of 0.16, 0.25, and 0.5 Hz for yoga inexperienced persons. We concomitantly measured the tissue oxygen index (TOI) using near-infrared spectroscopy in the forehead and the vagal (high frequency; HF) component of HRV during a resting period, KB period, and recovery period. We observed no difference between the TOI of the right and left brains of the KB period at any tempo. In the comparison between the resting period and the recovery period, TOI of the right DLPFC significantly decreased in the recovery period compared to the rest period only in the 0.25 Hz tempo. Furthermore, a significant positive correlation was found between the difference in recovery period from resting period in both the right TOI and the HF component of HRV in the 0.25 Hz tempo. From this result, it was suggested that practice of KB with 0.25 Hz tempo for 1 minute by yoga inexperienced persons reduced the right DLPFC activity, and which was related with cardiac parasympathetic nerve activity.
