Ingles Janet L, Eskes Gail A
School of Human Communication Disorders, Dalhousie University, Halifax, Canada.
J Int Neuropsychol Soc. 2007 Jan;13(1):110-9; discussion 108-9. doi: 10.1017/S1355617707070142.
Theories of the cognitive impairment underlying letter-by-letter reading vary widely, including prelexical and lexical level deficits. One prominent prelexical account proposes that the disorder results from difficulty in processing multiple letters simultaneously. We investigated whether this deficit extends to letters presented in rapid temporal succession. A letter-by-letter reader, G.M., was administered a rapid serial visual presentation task that has been used widely to study the temporal processing characteristics of the normal visual system. Comparisons were made to a control group of 6 brain-damaged individuals without reading deficits. Two target letters were embedded at varying temporal positions in a stream of rapidly presented single digits. After each stream, the identities of the two letters were reported. G.M. required an extended period of time after he had processed one letter before he was able to reliably identify a second letter, relative to the controls. In addition, G.M.'s report of the second letter was most impaired when it immediately followed the first letter, a pattern not seen in the controls, indicating that G.M. had difficulty processing the two items together. These data suggest that a letter-by-letter reading strategy may be adopted to help compensate for a deficit in the temporal processing of letters.
逐字阅读背后认知障碍的理论差异很大，包括词前和词汇层面的缺陷。一种著名的词前解释认为，该障碍是由于同时处理多个字母存在困难所致。我们研究了这种缺陷是否扩展到快速连续呈现的字母。我们让逐字阅读者G.M.进行了一项快速序列视觉呈现任务，该任务已被广泛用于研究正常视觉系统的时间处理特征。将其与6名无阅读缺陷的脑损伤个体组成的对照组进行比较。在快速呈现的单个数字流中，两个目标字母被嵌入到不同的时间位置。在每个数字流之后，报告两个字母的身份。与对照组相比，G.M.在处理完一个字母后需要更长的时间才能可靠地识别第二个字母。此外，当第二个字母紧跟在第一个字母之后时，G.M.对第二个字母的报告受影响最大，而对照组中未出现这种模式，这表明G.M.难以同时处理这两个项目。这些数据表明，可能会采用逐字阅读策略来帮助弥补字母时间处理方面的缺陷。
