Klich R J, Ireland J V, Weidner W E
Cortex. 1979 Sep;15(3):451-70. doi: 10.1016/s0010-9452(79)80070-2.
The articulatory and distinctive features in 825 consonant substitutions produced by nine subjects with apraxia of speech were analyzed. The articulatory and distinctive features of the target consonants were retained beyond chance levels. The substitution patterns observed were very systematic in that more substitutions were made in the initial word position and stops, alveolars, and voiced consonants were used most often as substitutes for target consonants. The retention and usage of the features in the substitutions were closely related to the phonological markedness of the features, Most of the markedness changes were from marked-to-unmarked. The relationships between distinctive features and their markedness suggest that apraxia of speech is primarily a phonological disorder that is manifested in articulatoriy changes. It appears therefore that speakers with apraxia of speech systematically reduce linguistic complexity and simplify the production of consonants. In addition, the substitutions made in apraxia of speech are similar to those made by children.
对9名言语失用症患者产生的825个辅音替代中的发音和区别特征进行了分析。目标辅音的发音和区别特征得以保留，且超出了偶然水平。观察到的替代模式非常有系统性，即更多的替代出现在单词起始位置，塞音、齿龈音和浊辅音最常被用作目标辅音的替代。替代中特征的保留和使用与这些特征的音系标记性密切相关，大多数标记性变化是从有标记到无标记。区别特征与其标记性之间的关系表明，言语失用症主要是一种音系障碍，表现为发音变化。因此，言语失用症患者似乎会系统性地降低语言复杂性，简化辅音的发音。此外，言语失用症中的替代与儿童所做的替代相似。
