COMPUTATIONAL PROBLEMS IN THE ANALYSIS OF EYE-MOVEMENT SIGNALS IN THEDETERMINATION OF VESTIBULOOCULAR REFLEX

The vestibule-ocular reflex preserves clear vision when the head is mo ving fast. Measurement of the vestibule-ocular reflex during the head autorotation test is usually calibrated using a dynamic technique in w hich the initial part of the eye movement signal and the corresponding part of the stimulating head movement signal are matched. Dynamic tec hniques can, however, be prone to generate excessively small or large calibration coefficients if a calibration segment of such a signal is corrupted by saccades or artifacts of large amplitudes. We have implem ented an effective improvement for computation of difficult signals, n ot infrequent in clinical data, by limiting influence of distorting pa rts in the eye movement signal. We also discuss pitfalls of parameter accuracy concerning gain and phase parameters of the vestibule-ocular reflex that are used to differentiate abnormal results from the normal . Furthermore, we call the ubiquituous Fast Fourier Transform method i nto question with regard to these signals. (C) 1997 Academic Press.