Mother tongue is pre-loaded software. You really don’t install it and configure during childhood. Once installed, it remains with the child forever.
Unfortunately, we disrespect this default language software and increase unnecessary stress of word-mapping by forcing kids to learn second language very early.
I don’t deny that you learn other languages. In fact, it is must that at least you keep learning at least one language, even after your graduation. It keeps your brain healthy and prevents memory loss and other disorders. But not for first 10 years.
But not at the cost of mother language!!
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‘Lost’ first languages leave permanent mark on the brain, new study reveals
“MRI scans show Chinese babies adopted by French-speaking Canadian families retain ‘unconscious’ knowledge of their mother tongue”
https://www.theguardian.com/education/2014/nov/20/lost-first-languages-leave-permanent-mark-on-the-brain-new-study-reveals?CMP=share_btn_fb
Mapping the unconscious maintenance of a lost first language
Using functional MRI we examined the unconscious influence of early experience on later brain outcomes. Internationally adopted (IA) children (aged 9–17 years), who were completely separated from their birth language (Chinese) at 12.8 mo of age, on average, displayed brain activation to Chinese linguistic elements that precisely matched that of native Chinese speakers, despite the fact that IA children had no subsequent exposure to Chinese and no conscious recollection of that language. Importantly, activation differed from monolingual French speakers with no Chinese exposure, despite all participants hearing identical acoustic stimuli. The similarity between adoptees and Chinese speakers clearly illustrates that early acquired information is maintained in the brain and that early experiences unconsciously influence neural processing for years, if not indefinitely.
http://www.pnas.org/content/early/2014/11/12/1409411111
