Cues for the control of ocular accommodation and vergence during postnatal human development
Cues for the control of ocular accommodation and vergence during postnatal human development
复制标题
DOI：
10.1167/8.16.14
复制
发表时间：
2008-01-01
影响因子：
1.8
通讯作者：
Candy, T. Rowan
中科院分区：
文献类型：
--
作者：
Bharadwaj, Shrikant R.;Candy, T. Rowan
当物体向纵深移动时，适应和聚焦有助于保持单一和集中的视觉体验。视网膜模糊和视差是调节和收敛的主要感官线索，在发育过程中，其相对重要性在很大程度上是未知的；在这一时期，眼睛和头部的生长需要不断地重新校准自我中心空间。在这里，我们测量了192名典型发育中的受试者(1.9个月到46岁)视网膜视差的发育重要性。受试者观看具有自然空间频谱的高对比度卡通目标，同时使用PowerReductor测量他们双眼的调节和聚焦反应。尽管注视眼在两种情况下产生了相似的跟踪眼球运动，但在单眼观看期间，调节增益相对于完全双眼观看时减少了。这一结果在三种形式的单眼闭塞中是一致的。调节增益在婴儿中最低，只有在7到10岁时才达到成年人的水平。正如预期的那样，在单眼条件下，会聚的增益也降低了。当4到6岁的孩子阅读20/40大小的字母时，他们的单眼调节收益达到了成年人的水平。总而言之，在自然视觉条件下，双眼观看似乎是必要的，以在典型的发育中的人类中产生完全的调节和收敛反应。
Accommodation and vergence help maintain single and focused visual experience while an object moves in depth. The relative importance of retinal blur and disparity, the primary sensory cues to accommodation and vergence, is largely unknown during development; a period when growth of the eye and head necessitate continual recalibration of egocentric space. Here we measured the developmental importance of retinal disparity in 192 typically developing subjects (1.9 months to 46 years). Subjects viewed high-contrast cartoon targets with naturalistic spatial frequency spectra while their accommodation and vergence responses were measured from both eyes using a PowerRefractor. Accommodative gain was reduced during monocular viewing relative to full binocular viewing, even though the fixating eye generated comparable tracking eye movements in the two conditions. This result was consistent across three forms of monocular occlusion. The accommodative gain was lowest in infants and only reached adult levels by 7 to 10 years of age. As expected, the gain of vergence was also reduced in monocular conditions. When 4- to 6-year-old children read 20/40-sized letters, their monocular accommodative gain reached adult-like levels. In summary, binocular viewing appears necessary under naturalistic viewing conditions to generate full accommodation and vergence responses in typically developing humans.