Inflectional versus derivational abilities of children with specific language impairment- A panorama from sequential cognition

Specific Language Impairment (SLI) is a neurodevelopmental disorder affecting language acquisition in the absence of frank neurological damage, hearing deficits, severe environmental deprivation, or mental retardation. Children with SLI have significant difficulties in syntax domain of language compared to semantics, while their acquisition of pragmatics is relatively spared. The purpose of the present study is to examine the judgment and revision of inflectional and derivational morphemes of children with specific language impairment (SLI). 31 children with SLI and 33 typically developing (TD) children participated in the study (age range 8-13 years). The stimuli consisted of 18 sentences with inflectional morphemes and 18 sentences with derivational morphemes for grammatical judgment and revision tasks. Inflectional and derivational performance of SLI group was compared with TD group on judgment and revision scores. Children with SLI were significantly poorer compared to TD children on inflectional operations (invariably on judging & revising) but performed like TD children on derivational morphemes. Within SLI, inflectional performance was significantly poorer than derivational performance. In contrast, TD children performed better on inflections than derivations. Findings supported the predictions and discussed using possible sequencing problems in children with SLI. The study describes the findings using sequential difficulties reported by procedural deficit hypothesis (PDH) in SLI.