Bilingualism and cognitive development: a study on the acquisition of number skills

Growing up as bilingual seem to exert some positive and negative effects on general cognitive functioning. Positive gains concern a earlier maturation of the attentional system in childhood and its later decline in adulthood. Bilinguals have been shown to be advantaged , compared to their monolingual peers in tasks requiring control of attention: they are more accurate in judging the grammaticality of sentences (Bialystok et al.1986); faster in the Attentional Network Test and in the Simon task (Costa et al 2007; Bialystok et al.2005).On the other hand bilinguals are disadvantaged in t asks requiring speech production : they are slower in acceding to the lexical representation of words (Ivanova, Costa,2007); they exhibit more tip of the tonguge states (Gollan & Silvenberg, 2001) and they show lower rates in retrieving verbal stimuli (Gollan,2002).If bilingualism can exert these influence sin boosting and hampering these so general cognitive functions, bilinguals children might also show these effects across domains.We surveyed the presence of these advantages and disadvantages in a domain so relevant as it is speaking two languages that is the number field. Bilinguals and monolinguals children were asked to perform three different number tasks: number Stroop, verification and dot counting.Unlike in the study of Bialystok et al. (2004; 2005) who employed a classical Stroop task, no difference was found between mono- and bilinguals as for the number Stroop effect. In the verification task, an associative confusion effect was found in the bilingual but not in the monolingual group. Finally, when children were asked to count, bilinguals performed equally well as their monolingual peers in counting items in the subitizing range only, whereas they were slower than their peers when they counted from 4 to 9 dots. This latter result, in particular, is consistent with many psycholinguistic studies claiming that bilinguals are disadvantaged in tasks requiring lexical access (Costa & Caramazza, 1999), and extend them to the number processing domain.