The sensitivity of the 2- to 4-month-old human infant accommodation system.
The sensitivity of the 2- to 4-month-old human infant accommodation system.
复制标题
2 至 4 个月大的人类婴儿住宿系统的敏感性。
DOI：
10.1167/iovs.09-4667
复制
发表时间：
2010
影响因子：
4.4
通讯作者：
Candy,TRowan
中科院分区：
文献类型：
--
作者：
Wang,Jingyun;Candy,TRowan
目的：本研究的目的是客观地比较婴儿和成人在双眼和单眼观看条件下调节系统的敏感度。方法：给2-4个月大的足月婴儿和老花眼前期成人呈现一个高对比度的卡通刺激，在平均2D(50 Cm)的屈光度附近正弦移动。在一次试验中使用了三个刺激幅度(0.25、0.50和0.75D)，在每个幅度变化中都有不可预测的刺激运动。用偏心验光记录25赫兹的调节反应。通过在右眼上方放置红外滤光片，使刺激成为单眼，以阻挡可见光，但通过光折射器的近红外波长，并允许从双眼记录反应。结果：使用傅立叶分析来确定刺激频率处的调节反应。显著的信噪比表明，平均而言，2到4个月大的婴儿对至少0.75D幅度的单眼刺激和0.75D和0.50D的双眼刺激产生了调节反应。结论：在2-4个月大的婴儿中，发育中的视觉系统对离焦的微小变化进行了补偿，相对于该年龄段发现的典型远视性屈光不正。
Purpose.: The goal of this study was to compare objectively the sensitivity of the accommodation system in human infants and adults under binocular and monocular viewing conditions.Methods.: Full-term infants from 2 to 4 months of age and pre-presbyopic adults were presented with a high-contrast cartoon stimulus moving sinusoidally in diopters around a mean position of 2 D (50 cm). Three stimulus amplitudes were used in one trial (0.25, 0.50, and 0.75 D), with unpredictable stimulus motion during each amplitude change. Eccentric photorefraction was used to record accommodative responses at 25 Hz. The stimulus was made monocular by placing an infrared filter over the right eye, to block visible light but pass the near-infrared wavelength of the photorefractor and allow responses to be recorded from both eyes.Results.: Fourier analysis was used to determine the accommodative response at the frequency of the stimulus. Significant signal-to-noise ratios indicated that, on average, the 2-to 4-month-old infants generated an accommodative response to at least the 0.75 D amplitude monocular stimulus and the 0.75 and 0.50 D binocular stimuli. Adults responded to the 0.25 D amplitude both binocularly and monocularly.Conclusions.: In infants 2 to 4 months of age, the developing visual system compensates for small changes in defocus relative to the typical amounts of hyperopic refractive error found at that age.