Methods Inf Med 2000; 39(02): 142-145
DOI: 10.1055/s-0038-1634277
Original Article
Schattauer GmbH

Spontaneous Fluctuations of Human Pupil Reflect Central Autonomic Rhythms

G. Calcagnini
1  Biomedical Engineering Lab., Istituto Superiore di Sanità and CISB “La Sapienza” University of Rome
F. Censi
2  Department of Information and System Science and CISB “La Sapienza” University of Rome
S. Lino
3  Department of Cardiovascular and Respiratory Sciences and Clinical Pathophysiology, “La Sapienza” University of Rome
S. Cerutti
4  Department of Biomedical Engineering, Polytechnic University of Milan, Italy
› Author Affiliations
Further Information

Publication History

Publication Date:
07 February 2018 (online)


Aim of this study is to assess whether and to what extent LF and HF rhythms contribute to spontaneous pupil diameter fluctuations at rest and during sympathetic activation by Head-Up Tilt Test 70°. ECG, Finapres and Respiration data from 10 normal subjects were recorded simultaneously to spontaneous pupil diameter fluctuations (SPDF). The respiratory rhythm and the LF component were clearly detected in all the SPDF series. The cross-spectrum analysis gave significant results (>0.5) in HF band. During tilt, a reduction in the total variability with a relative increase of the LF component was observed in HR, BP and SPDF signals. The multivariate analysis of the SPDF and of the cardiovascular variability series allows new insights into the physiology of pupil neural control. The effect of tilting on SPDF spectra and the physiological background of the pupil control are consistent with the hypothesis that pupil fluctuations reflect a generalized increase of the sympathetic tone.