Morphological Information and Memory Resources in Children's Processing of Relative Clauses in German

We investigated the processing of agreement marking and case marking in the comprehension of German relative clauses in 48 seven-year-old monolingual German-speaking children in a picture selection task. We examined the relation between the effectiveness of these different morphological cues and individual memory resources as measured by a digit-span test. Relative clauses were disambiguated either by agreement marking on the embedded verb or by case marking on the embedded determiner phrase. The results show that subject-extracted relative clauses (subject RCs) are more easily comprehended than object-extracted relative clauses (object RCs) and that case disambiguation is more effective than agreement disambiguation. Moreover, we found a relation between individual phonological short-term memory and the effectiveness of the different disambiguating cues in the comprehension of object RCs but not in the comprehension of subject RCs. We found that: (i) children with a low-digit span score have difficulties in the comprehension of case and agreement disambiguated object RCs, (ii) children with a medium-digit span score have difficulties in the comprehension of agreement disambiguated object RCs but not difficulties with case disambiguated object RCs, and (iii) children with a larger digit span score have no difficulties in the comprehension of agreement and case disambiguated object RCs. We explain our results under the Diagnosis and Repair Model (Fodor & Inoue, 2000) by arguing that children by age 7 have adult-like competence and processing strategies for these structures and that observable differences depend on individual memory resources as measured by a digit span task.