Bitschnau W
Institut für Schulpsychologie und Bildungsberatung, Feldkirch, Vorarlberg.
Z Kinder Jugendpsychiatr Psychother. 1997 May;25(2):82-94.
For some time the question of a visual impairment in dyslexic children has been a source of controversy in the literature. Depending on the method used, the findings point either to receptor or neural impairment or to a visual deficit in information processing. The question remains of whether these findings mask retardation in the motor planning and execution of a response.
In this investigation 61 children (15 dyslexic boys and 15 dyslexic girls aged 8 years 0 months to 10 years 8 months and 16 non-dyslexic boys and 15 non-dyslexic girls aged 8 years 0 months to 10 years 10 months) were tested using a computer-assisted visual display method (visual scan procedure). The results were included into a linear regression model.
Compared to the non-dyslexic children the dyslexic children had a significant retardation in the speed of motor response (MANCOVA, Mann-Whitney U-test). For the "pure" visual process no differences in time course were found. Another important findings is the surprisingly wide range of results obtained for individual dyslexic children. In some instances there were deviations as great as 3.6 sigma (SEM). These findings indicate that we may be dealing with an individual partial impairment. It should be noted that the calculation of the linear regression model cannot be detailed for the group of dyslexic children. The prerequisites for a linear regression model are not satisfied. The comparability of the results is therefore limited.
We cannot assume there will be a manifest visuomotor impairment in all dyslexic children when the stimulus is presented at the center and periphery of the field of vision. However, if such an impairment is present it is highly likely that the findings contain a mixture of retardation of pre-motor and visual decision latency. This would have substantial consequences for therapy, as visuomotor perception training would not be indicated in all instances. Some dyslexic children, both boys and girls, achieve completely "normal" results.
一段时间以来，诵读困难儿童是否存在视力障碍的问题在文献中一直存在争议。根据所使用的方法，研究结果要么指向感受器或神经损伤，要么指向信息处理方面的视觉缺陷。问题仍然是这些发现是否掩盖了反应的运动计划和执行方面的迟缓。
在这项研究中，使用计算机辅助视觉显示方法（视觉扫描程序）对61名儿童（15名8岁0个月至10岁8个月的诵读困难男孩和15名诵读困难女孩，以及16名8岁0个月至10岁10个月的非诵读困难男孩和15名非诵读困难女孩）进行了测试。结果被纳入线性回归模型。
与非诵读困难儿童相比，诵读困难儿童在运动反应速度上有显著迟缓（多变量协方差分析，曼-惠特尼U检验）。对于“纯粹”的视觉过程，未发现时间进程上的差异。另一个重要发现是，个别诵读困难儿童获得的结果范围惊人地广泛。在某些情况下，偏差高达3.6标准差（标准误）。这些发现表明，我们可能面对的是个体部分损伤。应该注意的是，对于诵读困难儿童组，线性回归模型的计算无法详细说明。线性回归模型的前提条件不满足。因此，结果的可比性有限。
当刺激呈现于视野中心和周边时，我们不能假定所有诵读困难儿童都会出现明显的视动障碍。然而，如果存在这种障碍，很可能这些发现包含了运动前延迟和视觉决策延迟的混合。这将对治疗产生重大影响，因为并非在所有情况下都适合进行视动感知训练。一些诵读困难儿童，无论男孩还是女孩，都能取得完全“正常”的结果。
