All children were recruited from the northwest of England, and all came from homes where English was spoken as the first www.selleckchem.com/GSK-3.html language. The children with SLI obtained a Core Language Score (CLS) of −1.25 SD or less on the Clinical Evaluation of Language Fundamentals-4th Edition, UK Standardisation (CELF-4 UK, Semel et al., 2003), and a Performance IQ (PIQ) score no less than 1 SD below the mean on the Wechsler Abbreviated Scale of Intelligence (WASI, Wechsler, 1999). TD children obtained standardised scores within one standard deviation (SD) of the mean on both the CELF-4 UK and WASI. The SLI and TD groups differed on
the CLS and CELF (Expressive Language Index – ELI, Receptive Language Index – RLI) language measures, but not on age or PIQ. Working memory, declarative memory, procedural memory and lexical and grammatical abilities were all assessed with well-studied measures of these domains. Working memory functioning was assessed with the Working Memory Test Battery for Children (WMTB-C, Pickering and Gathercole, LY2835219 manufacturer 2001). This test comprises eight subtests, which were designed to assess the central executive, phonological loop, and visuo-spatial sketchpad components
of Baddeley’s (2003) model of working memory (for validation study see Gathercole et al., 2004). All subtests from the WMTB-C are standardised to a mean of 100 and SD of 15. The central executive component is assessed by the Listening Recall, Counting Recall, and Backward Digits Recall subtests, all of which require the short-term storage and processing of information. On Listening Recall, children are presented with a series of sentences. For each sentence, they must first provide true/false judgements on the sentence’s semantics, and then recall the sentence-final word. The Listening Recall subtest is an adaptation of the Competing Language Task (Gaulin and Campbell, 1994). On the Counting Recall task, children are presented with pictures of randomly presented dots, and are asked to count and then recall the
dots. Counting Recall is based on the counting span task developed by Case et al. (1982). The Backward Digit Recall subtest, in which children are asked to repeat a string of digits in reverse order, mafosfamide is similar to the Backward Digit Span Task in the Wechsler Intelligence Scales (e.g., Wechsler, 2003 and Wechsler, 2008). These subtests are likely to probe not only Baddeley’s central executive, but also Cowan’s focus of attention. Note that while all these subtests are designed to measure central executive (and likely attentional) working memory functioning, as they require both the short-term storage and processing of information, it is important to emphasise that all have a verbal component, and thus likely depend more generally on verbal aspects of working memory. The WMTB-C does not include central executive tasks which can be considered non-verbal.