Eden G F, Stein J F, Wood H M, Wood F B
University Laboratory of Physiology, Oxford, England.
Vision Res. 1994 May;34(10):1345-58. doi: 10.1016/0042-6989(94)90209-7.
It has been suggested that eye movement abnormalities seen in dyslexics are attributable to their language problems. In order to investigate this claim, we studied eye movements in dyslexic children, during several non-reading tasks. Dyslexic children were compared to normal and backward readers on measures of fixation, vergence amplitude, saccade and smooth pursuit. The results were compared to the children's phonological ability. Dyslexic children (n = 26) had significantly worse eye movement stability during fixation of small targets than normal children (n = 39). Vergence amplitudes were lower for dyslexics than for controls. A qualitative assessment of saccadic eye movements revealed that dyslexics exhibit fixation instability at the end of saccades. Assessment of smooth pursuit revealed poor smooth pursuit in the dyslexic group, particularly when pursuing a target moving from left to right. Dyslexic children also performed significantly worse than normal children on a test of phonological awareness (Pig Latin). Eye movement results were studied in the light of the findings on phonological awareness: dyslexics with small vergence amplitudes also always have poor phonemic awareness. However, poor fixation control is found in dyslexics with or without poor phonological ability. The backward reading children performed similar to the dyslexics on all tests, suggesting that the deficiencies observed in this study are not specific to children with dyslexia. The problems experienced by the children (revealed by a questionnaire) are in agreement with those measured in terms of eye movement recordings and phonemic awareness. Sex, handedness, IQ or the presence of attention deficit disorder (ADD) did not appear to influence the children's performances on any of the eye movement tasks. The presence of oculomotor abnormalities in a non-reading task strongly suggests that the underlying deficit in the control of eye movements seen in dyslexics is not caused by language problems alone.
有人认为诵读困难者出现的眼球运动异常是由他们的语言问题导致的。为了探究这一说法，我们研究了诵读困难儿童在几项非阅读任务中的眼球运动。将诵读困难儿童与正常阅读儿童和阅读落后儿童在注视、聚散幅度、扫视和平稳跟踪等指标上进行了比较。并将结果与儿童的语音能力进行了对比。诵读困难儿童（n = 26）在注视小目标时的眼球运动稳定性明显比正常儿童（n = 39）差。诵读困难儿童的聚散幅度比对照组低。对扫视眼球运动的定性评估显示，诵读困难者在扫视结束时表现出注视不稳定。对平稳跟踪的评估显示，诵读困难组的平稳跟踪能力较差，尤其是在跟踪从左到右移动的目标时。诵读困难儿童在语音意识测试（倒读英语）中的表现也明显比正常儿童差。根据语音意识的研究结果对眼球运动结果进行了分析：聚散幅度小的诵读困难者语音意识也总是很差。然而，无论语音能力是否差，诵读困难者都存在注视控制不佳的情况。阅读落后儿童在所有测试中的表现与诵读困难儿童相似，这表明本研究中观察到的缺陷并非诵读困难儿童所特有。孩子们（通过问卷揭示）所经历的问题与通过眼球运动记录和语音意识测量的结果一致。性别、用手习惯、智商或注意力缺陷多动障碍（ADD）的存在似乎都不会影响孩子们在任何眼球运动任务中的表现。在非阅读任务中存在眼球运动异常强烈表明，诵读困难者在眼球运动控制方面的潜在缺陷并非仅由语言问题引起。
