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.

中文翻译：

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发育性字母位置阅读障碍。

字母位置阅读障碍（LPD）是一种外围阅读障碍，会导致单词内字母顺序错误。到目前为止，仅报告了获得性LPD的病例。这项研究通过对具有发展性阅读障碍的II讲希伯来语的个体的测试，提出了选择性LPD的发展形式。该研究使用多种测试方法来探讨阅读障碍中的错误类型及其对阅读的影响：朗读，词汇决策，同等决策，定义和字母命名。研究结果表明，具有发展性LPD的个人在正交视觉分析器的字母位置编码功能方面存在缺陷，这导致单词中字母位置的规格不足。字母位置错误主要发生在相邻的中间字母中，这是因为该错误创建了另一个现有单词。参与者没有表现出输出不足或语音意识不足。缺陷的选择性导致字母位置错误，但没有字母标识错误，并且单词之间没有迁移，这支持了字母位置编码功能的存在，该功能与字母识别和字母到单词的绑定是分开的。