TABLE 6.

Correlation analysis of pupillary dynamics and autonomic indices at rest and deep breathing.

	Resting condition		Deep breathing
	PUI	SE	PUI	SE
HR	0.017	0.213	0.017	0.177
RMSSD	0.462*	–0.117	0.384*	−0.439*
SBP	0.045	–0.237	0.045	0.435*
DBP	–0.138	–0.295	–0.138	0.287
sdSBP	0.028	0.223	0.028	0.414*
sdDBP	0.045	0.289	0.045	0.260
BRS	0.228	–0.343	0.228	–0.318
BR	–0.104	0.296	0.050	–0.078
sdRC	–0.116	0.070	–0.107	0.085
SCL	−0.412*	0.130	−0.569**	0.029
SCF	−0.428*	0.245	−0.422*	0.474*

HR: mean heart rate, RMSSD: root mean square of heart beat interval differences SBP: systolic blood pressure, DBP: systolic blood pressure, sdSBP: standard deviation of SBP, sdDBP: standard deviation of DBP, BRS: bradycardic baroreflex sensitivity, BR: breathing rate, sdRC: standard deviation of respiratory cycles, SCL: skin conductance level, SCF: skin conductance fluctuations, PUI: pupillary unrest index, SE: sample entropy of pupil diameter. * p < 0.05, ** p < 0.01.