Dynamic analysis of age-related responses of the vestibulo-ocular reflex.
Dynamic analysis of age-related responses of the vestibulo-ocular reflex.
复制标题
前庭眼反射与年龄相关的反应的动态分析。
DOI：
10.1159/000418954
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发表时间：
1990
影响因子：
--
通讯作者：
Kevorkian,KF
中科院分区：
文献类型：
--
作者：
O'Leary,DP;Davis,LL;Kevorkian,KF
MethodsThe VAT is based on 18 s of voluntary head oscillations which sweep over ar ange of frequencies. Seated subjects are instructed to fixate on a target positioned at a known distance and to move their heads from side to side (horizontal test) or nose up-down (vertical test) in synchrony with a computer-generated tone throughout 18 s. The audible cue begins slowly (0.5 Hz) and then sweeps linearly through a range to 6 Hz. Electrooculographic (EOG) electrodes are positioned conventionally for recording horizontal and vertical eye positions, and a rotational velocity head sensor fixed to a head strap records head movements (fig. 1). The head strap is adjustable to minimize slippage. A portable computer system controls the test, digitizes the eye and head movements, analyzes the data, and produces graphs of gain and phase versus frequency for evaluation. Methods of data acquistion and analysis were described previously [6, 7]. Each patient is tested three or more times in both the horizontal and vertical planes. The portable VAT was used on site at the Andrus Gerontology Center, University of Southern California, and at various senior citizen centers in the greater Los Angeles area. VOR data from 46 volunteer subjects ranging in age from 65 to 77 years were recorded using the VAT. Because our goal was to selectively test elderly subjects without vestibular pathology, specific selection criteria were used in the final data analysis. Subject selection criteria were based on the following:(1) negative history of vertigo or dysequilibrium;(2) no medication such as tranquilizers, barbiturates, amphetamines or alcohol 48 h prior to testing;(3) negative history of ear surgery;(4) negative history of head trauma, and (5) negative history of moderate to profound hearing loss or tinnitus. Subjects with minor hearing loss were accepted into the study as this was a common complaint in many
