Zusammenfassung
Eine plötzliche Zunahme der Intensität eines Reizlichtes löst eine gedämpfte Schwingung des corneoretinalen Potentials des Menschen aus. Die Schwingung wurde früher mit Hilfe eines mathematischen Modells beschrieben. Die vorliegende Untersuchung betrifft eine Prüfung auf Linearität des postulierten Rückkopplungsvorganges. Elf Versuchspersonen wurden für 4 Std einem sinusförmig modulierten Reizlicht ausgesetzt. Die Perioden des Reizlichtes variierten in verschiedenen Versuchen von 15–32 min. Eine Fourier-Serie wurde an die Meßpunkte angepaßt. Der Einschluß von harmonischen Gliedern verbesserte die Anpassung signifikant. Diese Beobachtung weist darauf hin, daß das System nicht-lineare Komponenten enthält.
Summary
A step change in light intensity evokes a damped oscillation in the human corneoretinal potential. A mathematical model has been developed to describe this damped oscillation. The present study was conducted in order to explore the linearity of the servomechanism hypothesized in this model.
Data were obtained from 11 test subjects who had been exposed for at least 4 hrs to light whose intensity varied sinusoidally; the periods of the forcing function were between 15 and 32 min. A truncated Fourier series was fitted to the response. It was found that inclusion of the harmonic terms improved the fits significantly. These findings indicate that the system is a non-linear one.
References
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Preliminary results were reported at the Annual Conference on Engineering in Medicine and Biology, San Francisco, California, 1966.
This study was supported by grants from the National Institutes of Health No. T5-GM-1607, 3T1-NB-5323, and FR-5364.
This investigation was the subject of a thesis for the Master of Science Degree of D.W.B. at Emory University, Atlanta, Georgia.
The use of the facilities of the Emory Biomedical Data Processing Center is gratefully acknowledged.
Publication No. 846 of the Division of the Basic Health Sciences.
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Benson, D.W., Kolder, H. & Homer, L.D. Non-linear response of the human corneoretinal potential to sinusoidal changes in light intensity. Pflügers Arch 295, 361–368 (1967). https://doi.org/10.1007/BF00362958
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DOI: https://doi.org/10.1007/BF00362958