Friedmann Naama, Rahamim Einav
Language and Brain Lab, School of Education, Tel Aviv University, Tel Aviv 69978, Israel.
J Neuropsychol. 2007 Sep;1(2):201-36. doi: 10.1348/174866407x204227.
Letter position dyslexia (LPD) is a peripheral dyslexia that causes errors of letter order within words. So far, only cases of acquired LPD have been reported. This study presents selective LPD in its developmental form, via the testing of II Hebrew-speaking individuals with developmental dyslexia. The study explores the types of errors and effects on reading in this dyslexia, using a variety of tests: reading aloud, lexical decision, same-different decision, definition and letter naming. The findings indicate that individuals with developmental LPD have a deficit in the letter position encoding function of the orthographic visual analyser, which leads to underspecification of letter position within words. Letter position errors occur mainly in adjacent middle letters, when the error creates another existing word. The participants did not show an output deficit or phonemic awareness deficit. The selectivity of the deficit, causing letter position errors but no letter identity errors and no migrations between words, supports the existence of letter position encoding function as separate from letter identification and letter-to-word binding.
字母位置诵读困难（LPD）是一种周边性诵读困难，会导致单词内字母顺序出错。到目前为止，仅报告过后天性LPD病例。本研究通过对11名患有发育性诵读困难的希伯来语使用者进行测试，呈现了发育性形式的选择性LPD。该研究使用多种测试方法，包括大声朗读、词汇判断、异同判断、定义和字母命名，探究了这种诵读困难中的错误类型及其对阅读的影响。研究结果表明，患有发育性LPD的个体在正字法视觉分析器的字母位置编码功能方面存在缺陷，这导致单词内字母位置的信息不完整。字母位置错误主要发生在相邻的中间字母上，且错误会形成另一个现存的单词。参与者未表现出输出缺陷或音素意识缺陷。这种缺陷的选择性，即导致字母位置错误但无字母识别错误且单词之间无迁移，支持了字母位置编码功能作为与字母识别和字母与单词绑定相分离的功能而存在。
