Investigation of Lexical and Inflectional Verb Production and Comprehension in French-Speaking Teenagers with Developmental Language Disorders (DLDs)

Little research has studied verb inflection and argument structure complexity effects in teenagers with developmental language disorders (DLDs). However, verb production and comprehension deficits that characterize younger children with DLD might persist over time. Seventeen French-speaking teenagers with DLD and seventeen controls (typical language, TL group) were tested with fLEX, an application designed to assess lexical and inflectional production and comprehension of three different verb types: intransitives, transitives and ditransitives, i.e., verbs that require none, one or two overt complements. Participants performed three tasks: action naming, sentence production and sentence comprehension involving third singular and plural present tense. Both groups performed similarly on action naming. Subject–verb agreement errors characterized participants with DLD both in sentence production and comprehension; however, verb–argument structure had no effect on any of the tasks. These results characterize verb deficits in teenagers with DLD as affecting inflectional processes rather than lexical ones: they are found in production and comprehension, persist until adolescence and are thus a target for evaluation and intervention in French-speaking teenagers. Results are discussed from a cross-linguistic perspective and in light of current theories on DLD.