For the last 20 years the effects of bilingualism have been extensively studied in experimental psychology. Despite numerous well-designed studies and meta-analysis there is no consensus whether or not there are executive functioning benefits in those who speak more than one language. Potentially small sample sizes and retrospective data collection are the cause of this.

The bilingual advantage is embedded in the theory that bilinguals constantly inhibit a non-target language when speaking; strengthening a non-specific cognitive domain inhibitory control mechanism resulting in benefits on tasks that require inhibition. By investigating cognition (in particular inhibitory control) throughout a child’s life alongside their exposure to a second language and other confounding variables we hope to finally gain consensus on whether bilingualism can affect cognition.

The bilingual advantage has been thought to have a protective effect over dementia and cognitive decline in older adults. By establishing that there is a bilingual advantage that could be protective of dementia has the potential to be a major public health advantage.