LXXXVIII Two Devices for Analysis of Nystagmus

Abstract

The recording of vestibular nystagmus by electronystagmography and other methods is becoming a common practice in clini-ca1 8 ,19 and experimental/" evaluation of the vestibular system. With adequate recording equipment, displacement of the pen is approximately proportional to angular displacement of the eyes, and paper speed determines the time base of the recordings. Several measurements of such records have been of primary interest: 1) duration of nystagmus, 2) total angular displacement of the eyes in the slow phase direction within some time interval, 3) angular velocity of the eyes in the slow phase direction of a number of points in time during the course of the response, and 4) number of nystagmus beats.With the exception of duration, which requires a decision only about nystagmus termination, these different measures of nystagmus can be very time-consuming when done manually. The present report describes two devices, one similar to a trace reader described by Benson and Stuart" and another complementary device, which facilitate measurement of nystagmus records and also facilitate the digital and analog presentation of the analyzed nystagmus data.

Spatial orientation in the squirrel monkey: An experimental and theoretical investigation

“…These devices (Guedry et al, 1968;Voots, 1969) are relatively easy to use, but inflexible. The analysis yielded by these methods is limited to only one component-of the response, and the methods may lead to operator dependent errors which, unintentionally lead to biased results.…”

Evaluation of a Simple Device for Scoring Nystagmus.

“…The Electrfinechanical Slope Computer (ESC) provided a system for comparative scoring (3). This device performs a semi-automated score of chart recorded nystagmus, and employs computer-aided printout and plot of slow phase slope.…”

Nystagmometry: the Art of Measuring Nystagmus Parameters by Digital Signal Processing

“…Aside from indirect techniques for more efficient analysis of paper tracings (Guedry and Turnipseed, 1968), several direct methods of signal analysis have been developed. On-line methods vary from simple electronic differentiation (Henriksson, 1955) or beat counting ( Torok and N y kiel, 1961) to more elabo rate analog or hybrid computer analysis (Coats and Black, 1973;Allum et ai, 1975;Täumer and Rohde, 1975;Böhmer and Pfaltz, 1978), or analysis by a small digital computer after analog to digital conversion (Loth et ai, 1971;Schilder et al, 1973).…”