Verbal declarative memory impairments in specific language impairment are related to working memory deficits

Abstract

This study examined verbal declarative memory functioning in SLI and its relationship to working memory. Encoding, recall, and recognition of verbal information was examined in children with SLI who had below average working memory (SLILow WM), children with SLI who had average working memory (SLIAvg. WM) and, a group of non-language impaired children with average working memory (TDAvg. WM). The SLILow WM group was significantly worse than both the SLIAvg. WM and TDAvg. WM groups at encoding verbal information and at retrieving verbal information following a delay. In contrast, the SLIAvg. WM group showed no verbal declarative memory deficits. The study demonstrates that verbal declarative memory deficits in SLI only occur when verbal working memory is impaired. Thus SLI declarative memory is largely intact and deficits are likely to be related to working memory impairments.

Keywords: Declarative memory; List learning; Memory; Specific language impairment; Verbal learning; Working memory.

Fig. 1

Mean number of words recalled during the encoding phase presented by group. The maximum number of words that could be recalled on a single trial is 14. Error bars show standard error.

Fig. 2

Proportions of recalled during the immediate and delayed recall condition reported by group. Panel A showed unadjusted recall scores. Panel B shows adjusted recall scores. Error bars show standard error.

Fig. 3

Mean d-prime values for delayed recognition reported by group. Panel A shows unadjusted d-prime values. Panel B shows adjusted d-prime values. Error bars show standard error.