Doubting the "bilingual cognitive advantage": just an effect of socio-economic status?

Several high-profile studies have shown that bilingual children outperform their monolingual peers in terms of several cognitive abilities -- including tests of verbal and nonverbal problem-solving, selective attention, flexibility (e.g., task-switching) and others. These studies have captured the public imagination and probably guided many moms to expose their kids to a second language.

But a new article in Developmental Science suggests that these impressive results may be somewhat overblown: bilingual children are likely to come from wealthier families than monolingual children, and since wealth has a strong and well-established relationship with cognitive function, these effects may be due not to a cognitive advantage but a financial one. None of the often-cited "bilingual advantage" papers seem to have measured socio-economic status independently.

Read full story in Developing Intelligence