ARE WORKING MEMORY MEASURES FREE OF SOCIO-ECONOMIC AND CULTURAL INFLUENCES?

This research investigated the hypothesis that working memory skills are independent of environmental factors such as socio-economic or cultural background. Study 1: Twenty Brazilian children aged 6 and 7 years from low socio-economic status families were evaluated on measures of working memory (verbal short-term memory and verbal complex span, taken form the AWMA: Automated Working Memory Assessment) and of vocabulary (expressive and receptive). They were compared with typically developing Brazilian children from the same region, matched on age, sex, and nonverbal ability from families of higher socio-economic status. Children from the low socioeconomic status group obtained significantly lower scores on the vocabulary tests but not on the verbal short-term memory measures, compared to their peers from a higher socio-economical background. Both groups differed on one of the two complex span measures - counting recall - but performed equally well on backwards digit recall. The results indicate that tests of verbal short-term memory and also backwards digit recall provide measures of cognitive abilities that are not biased by the quality of the child's socio-economical background.
Study 2: The Brazilian children were also compared to a population of Portuguese- speaking, immigrant children growing up in Luxembourg, evaluated on the same measures. Results will specify whether or not, in addition to being independent of socioeconomic background, verbal short-term memory and backwards digit recall are also free of cultural bias. As these measures are also highly sensitive to language ability, they may provide useful methods for diagnosing language disorder that are independent of environmental opportunity.