Researchers at University College in London found that increased density of white matter connections on the left auditory cortex (left Heschl's) could predict whether a person would be fast or slow to learn new foreign language sounds.
Couple of thoughts here -
1. It may not be your imagination that you or your child has to work harder to learn a foreign language (this goes for many other subjects). It may be your connectivity...at least at this point in time.
2. Rigid and absolute ideas about "a well-rounded education" ought to be viewed with skepticism. Sternberg's idea of successful intelligence (i.e. an intelligence based on one's personal gifts and interests rather than a predetermined rigid standard) is a much better end goal of education.
3. Findings such as this are certainly only the tip of the iceberg - many more structural brain differences will be found that predict whether specific learning tasks are easily acquired or hard.
4. Folks with strong left hemispheric processing (left-brain advantage) are the natural multilinguals, and while folks with dominant right hemispheric processing may struggle. This also fits with the association of dyslexia with stronger right-hemispheric processing. Foreign language waivers are standard school accommodations for many dyslexics.
Brain Structure Predicts Learning of Foreign Language Speech Sounds pdf
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