The acquisition of phonology and the classification of speech disorders in German-speaking children
Phonological acquisition has been a major research topic for the past three decades. Several different theoretical concepts, accounting for the course of phonological acquisition, have emerged. While all these theories agree the need to explain language-specific differences during the course of development, they all also strongly argue for a universal pattern. This thesis aims to provide evidence for phonological theory in a cross-linguistic context by examining monolingual children acquiring German as their native language. A cross-sectional study of 177 normally developing children aged 1;6 to 5; 11 was found to generally support the concept of universality but also showed significant acquisition differences especially in comparison with English, a closely related language. It will be argued that to date only the concept of phonological saliency (So & Dodd, 1994; Zua Hua & Dodd, 2000) is able to fully explain language-specific findings. However, evidence for phonological theory cannot only be validated by using data from developmental cross-linguistic studies but also from data describing phonologically disordered children. The nature of the errors made and also the children's developmental history might provide information concerning the prerequisites for normal speech development and the cognitive processes involved in speech perception and production. ... This thesis will argue that developmental speech disorders of unknown origin follow a language-independent course that is constrained by a universal pattern. On the basis of normative data for any language investigated, it should be possible to detect universal subgroups of speech disorders across languages. The clinical implication of this conclusion is that therapy techniques can be applied cross-linguistically.