Sympathetic-parasympathetic Ratio of Our Gaze

"The LF (0.04-0.15 Hz) and HF (0.16-0.4 Hz) ratings were recorded for 24 hours (day and night average) by Holter recording system~Photographs of both irises of the healthy volunteers were taken . An image software program was used to draw circular limits over the iris exterior circle (IEC), coloretta circle (CC), and pupil circle (PC) on digital photographs. The areas between the circles were measured. The likelihood that the IRIS ratio was equal to the LF/HF ratio was calculated using the formula \[IEC-PC¬\] - \[CC-PC\] / \[CC-PC\]."