Is there a better way to judge who should live where and what belonging to a country really means? Something more enlightened than the permanent residency form that has provoked so much criticism recently. Sadly, a neuroscientific approach to how language marks you out as a recent arrival is unlikely to be any more forgiving. Although very young children respond equally to all languages, infants raised in a Japanese-only environment start to lose the ability to distinguish ‘l’ and ‘r’ sounds between six and 12 months old. English-speaking children get better at making the distinction.
Even if you learn a second language to a very high standard, you’ll never speak it like a native unless you were exposed to it by around the age of eight. This is mirrored by brain scans. Languages you learn after eight go into a subtly different area of the brain to those acquired earlier.
None of this suggests that we should include MRI scans in nationality tests. But it does show how hard we must work to implement modern and enlightened standards to determine who gets to live where.
Listen to this week’s podcast at theguardian.com/lifeandstyle/series/neuroscientist-explains
