JCPSLP VOL 15 No 1 March 2013

Computer-assisted assessment and intervention

Growth in expressive grammar following inter­ vention for 3- to 4-year-old preschoolers with SLI Karla N. Washington and Genese Warr-Leeper

This study analysed grammatical development in a sample of 3- to 4-year-olds with specific language impairment (SLI) over time. The authors sought to determine if expressive grammar intervention resulted in accelerated gains in morphosyntax to “within normal limits” performance in expressive grammar for this age group. For this analysis, spontaneous language outcomes following expressive grammar intervention were compared between preschoolers receiving intervention (n = 22) and those not receiving intervention, no intervention waitlist-controls (n = 12). We examined: (a) growth in grammatical complexity and morpheme use, and (b) per cent error rates in three grammatical categories. We found that intervention was more effective than no intervention in facilitating accelerated performance for grammatical complexity, growth in morpheme use, and lower per cent error rates in targeted grammatical categories. This study provides evidence that expressive grammar intervention is associated with accelerated development in grammar skills for preschoolers with SLI. S pecific language impairment (SLI) is characterised by persistent difficulty in acquiring age-appropriate language skills, despite having normal nonverbal IQ and no known secondary impairments (Leonard, 1998). Grammar deficits are considered a diagnostic feature of SLI (Cleave & Rice, 1997). Finite verb forms, including auxiliary is , are , am , pose challenges because these carry obligatory marking for tense and agreement, and are often omitted in productions (Cleave & Rice, 1997). Finite verb endings (e.g., ing ) and other functor words (e.g., articles ) are also vulnerable to omission (Cleave & Rice, 1997). It is hypothesised that children with SLI experience specific processing limitations that impact on their language learning ability (Archibald & Gathercole, 2007; Leonard et al., 2007). For example, poor short-term memory within the phonological loop can affect these children’s ability to

establish well-specified phonological representations for specific language forms, e.g., finite verbs (Leonard et al., 2007). These difficulties can affect the speed of information processing and the ability to maintain the information presented, resulting in the observed production omissions (Leonard et al., 2007). Interventions addressing grammar deficits in preschoolers with SLI have been successfully implemented (Leonard, Camarata, Pawlowska, Brown, & Camarata, 2006; 2008; Yoder, Molfese, & Gardner, 2011). However, we also know that intervention for expressive grammar deficits may be more effective if there are no corresponding receptive language impairments (Law, Garrett, Nye, & Dennis, 2012), suggesting that for children with primary deficits in expressive grammar, positive outcomes following intervention are possible. The authors of the current paper explored the effectiveness of expressive grammar intervention compared to no intervention in facilitating grammar development in 3- to 4-year-olds with expressive SLI. Children were assigned to computer-assisted intervention, table-top intervention, and a waitlist-control group (Washington, Warr-Leeper, & Thomas-Stonell, 2011). A newly developed computer program, My Sentence Builder , designed for use with preschoolers with SLI with primary expressive grammar deficits (Washington & Warr-Leeper, 2006), was utilised for the computer-assisted intervention. Visual support was provided by colour-coded screens containing pictures for subjects, verb actions, and objects in target sentences (i.e., present progressive). For table-top intervention, objects in play, together with books and picture cards with actions providing visual supports were used to facilitate grammatical productions in a drill-play format. Both interventions resulted in significantly higher total scores for spontaneous language samples, calculated using Developmental Sentence Scoring (DSS; Lee, 1974), at 3 months and at 6 months post-intervention compared to no intervention. The authors concluded that accelerated development in grammatical complexity occurred for preschoolers enrolled in intervention compared to waitlist- controls (Washington et al., 2011). However, differences between intervention and no intervention for the magnitude of growth in grammar skills that occurred and was maintained over time was not explored in the 2011 study. This type of analysis would yield important information on whether the intervention resulted in accelerated gains in grammatical development in preschoolers with SLI and thus provide stronger support for this intervention.

This article has been peer- reviewed Keywords expressive grammar intervention growth preschoolers specific language impairment spontaneous language

Karla N. Washington (top)

and Genese Warr-Leeper

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JCPSLP Volume 15, Number 1 2013

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