A method for monitoring autonomic nervous activity by pupillary flash response

This paper proposes a noninvasive method for estimating autonomic nervous activity from changes in dynamic parameters of a pupillary flash response. Our method is derived based on an analysis that clarifies the relationship between the autonomic nervous activity and the dynamic parameters using the human pupillary muscle plant model developed in our previous study. Moreover, we show that pupillary responses to an identical flash vary depending on the initial pupil diameter when evaluating autonomic nervous activity by means of changes in the dynamic parameters. The efficacy of this method is demonstrated by applying it to a subject whose autonomic nervous activity is modified by drugs affecting the autonomic nervous system. © 2000 Scripta Technica, Syst Comp Jpn, 31(4): 22–31, 2000