Discover Magazine has an article on how sign language in Nicaragua is being used to show how language affects thought.
Specifically, those who learned NSL before it developed specific gestures for left and right perform more poorly on a spatial awareness test than children who grew up knowing how to sign those terms.
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Pyers explains, “The first-cohort signers find these tasks challenging because they do not have the language to encode the relevant aspects of the environment that would help them solve the spatial problem.†She added, “[They] did not have a consistent linguistic means to encode ‘left of’.â€
That makes it all the more important that students learn things when they are young.
It doesn’t mean we should quit trying to teach them when they are older though.