Can measures of executive function disentangle language disorder and disadvantage

Scientific Conference (2013, June 27)

Identifying specific language impairment (SLI) in polyglots or in children growing up in poverty is complex because it is often difficult to determine whether low language scores are attributable to ... [more ▼]

Identifying specific language impairment (SLI) in polyglots or in children growing up in poverty is complex because it is often difficult to determine whether low language scores are attributable to reduced linguistic exposure or to the presence of a neurolinguistic deficit. This cross-cultural research presents data on different groups of children with an SLI diagnose in Luxembourg, Portugal, and Brazil who all speak Portuguese as their first language and were tested on the same battery of language (expressive/receptive vocabulary and syntactic comprehension) and executive function measures (verbal/visuo-spatial working memory, focused attention, and inhibitory suppression). In Luxembourg, 15 Portuguese-Luxembourgish bilingual 8-year-olds with an SLI diagnose (Bi-SLI) took part in the study. Their performance was compared to 35 typically developing Portuguese-Luxembourgish bilinguals from Luxembourg (Bi-TD) and to 35 typically developing monolinguals from Portugal (Ml-TD). Groups were matched on chronological age, socioeconomic status, and fluid intelligence and all children came from low income families. Results indicate that despite large differences in their language scores (Bi-SLI < Bi-TD < Ml-TD), the groups exhibited comparable performance on the measures of visuo-spatial working memory, focused attention, and inhibitory suppression. Group differences emerged on the verbal working memory measures with Bi-SLI children performing significantly less well than the bilingual and monolingual TD groups that manifested comparable performance. The data seems to suggest that executive function deficits in SLI are not domain general but limited to the verbal domain. Whether these findings extend to monolingual SLI children in Portugal and Brazil will be discussed. [less ▲]

Poverty and executive functions A latent variable study of children growing up in enriched and deprived conditions in Brazil

Poster (2013, April)

Effects of impoverished environmental conditions on working memory performance

in Memory (2013), Mar 26. [Epub ahead of print]

This cross-cultural study investigates the impact of background experience on four verbal and visuo-spatial working memory (WM) tasks. Eighty-four children from low income families were recruited from the ... [more ▼]

This cross-cultural study investigates the impact of background experience on four verbal and visuo-spatial working memory (WM) tasks. Eighty-four children from low income families were recruited from the following groups: (1) Portuguese immigrant children from Luxembourg impoverished in terms of language experience; (2) Brazilian children deprived in terms of scholastic background; (3) Portuguese children from Portugal with no disadvantage in either scholastic or language background. Children were matched on age, gender, fluid intelligence, and socioeconomic status and completed four simple and complex span tasks of WM and a vocabulary measure. Results indicate that despite large differences in their backgrounds and language abilities, the groups exhibited comparable performance on the visuo-spatial tasks dot matrix and odd-one-out and on the verbal simple span task digit recall. Group differences emerged on the verbal complex span task counting recall with children from Luxembourg and Portugal outperforming children from disadvantaged schools in Brazil. The study suggests that whereas contributions of prior knowledge to digit span, dot matrix, and odd-one-out are likely to be minimal, background experience can affect performance on counting recall. Implications for testing WM capacity in children growing up in poverty are discussed. [less ▲]

Working memory, executive functions, language, and socio-economic status - A Latent Variable Study of Children From Brazil

Scientific Conference (2011, July)

This study explores the underlying factor structure of executive functions, working memory, and language in young children from a range of social backgrounds. A particular interest was to investigate the ... [more ▼]

This study explores the underlying factor structure of executive functions, working memory, and language in young children from a range of social backgrounds. A particular interest was to investigate the effect of socioeconomic status on the identified factor structure and to explore whether potential links might be mediated by stimulation in the home and/or nutritional status. A population of 400, six- and eight-year-olds, completed multiple measures of working memory, short-term memory, response inhibition, conflict resolution, focused attention, fluid intelligence, and language. Socioeconomic status was indexed by the education and occupation of the caregivers and household income. Anthropometrical assessments were conducted to establish nutritional status; Environmental stimulation was explored via interviews conducted with the caregivers. The results contribute to theoretical conceptions of the components of executive functions in childhood and their link with related cognitive systems. They also contribute to an increased understanding of the relationship between poverty and cognitive achievement. [less ▲]