Wavelet analysis of the pupil's autonomic flow

Gonçalo Macedo Leal, Pedro Vieira, Carlos Marques-Neves

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

1 Citation (Scopus)


This project presents the preliminary results of the Pupillometer project, developed last year in the Institute of Molecular Medicine, in Lisbon. The Pupillometer is a stable and robust optical equipment for detecting, with high resolution, the area of the pupil and its variation on a temporal scale. It allows us to detect the pupil's oscillations, which represent the autonomic nervous system behavior, that is, the parasympathetic and. sympathetic equilibrium. The Pupillometer has an algorithm developed. in Matlab, which detects the pupil's properties at the output of the acquisition system (Leal et al., 2009). We can thus register the variation of the pupil's area, perimeter, centroids and diameter during the period of the acquisition of data. Using the Matlab Wavelet toolbox some time-frequency analysis was made of the first results. These were obtained giving the subjects a stimulus such as a flash of light or putting their hand in a bucket of cold water. A Pupillogram, an ECG and a Pneumogram were simultaneously acquired, of the subject and, during that time, the stimulus was pplied. By examining the time-frequency analysis, we can see the same frequency components behavior in the subjects, but it is still too soon to be certain. Although we have not reached many results yet, we believe that in a couple of months we will have gathered more significant and interesting results.

Original languageEnglish
Title of host publicationTechnology and Medical Sciences, TMSi 2010 - Proceedings of the 6th International Conference on Technology and Medical Sciences
Number of pages4
Publication statusPublished - 2011
Event6th International Conference on Technology and Medical Sciences, TMSi 2010 - Porto, Portugal
Duration: 21 Oct 201023 Oct 2010


Conference6th International Conference on Technology and Medical Sciences, TMSi 2010


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