This is a very interesting TEDx Talk about the “benefits of a bilingual brain” by Mia Nacamulli. – I only would like to point out that if grown ups learn a new language, they usually do it in a very “conventional” way, which is rule-based (i.e. using books, learning grammar first) which leads to using one side of the brain only, like it is mentioned in this film/talk.
When adults learn a new language in the same spontaneous, memory based way like children, the brain activity is then similar to the one of children who acquire a new language by involving both hemispheres. The approach is then less rational and more emotional.
What are you, a compound bilingual, a coordinate bilingual or a subordinate bilingual?
A compound bilingual:
The person learns the two languages in the same context where they are used concurrently, so that there is a fused representation of the languages in the brain. – This is the case when a child is brought up by bilingual parents, or those from two different linguistic backgrounds. This is additive in nature.
A coordinate bilingual:
The person learns the languages in separate environments, and words of the two languages are kept separate with each word having its own specific meaning.
A subordinate bilingual:
The person attained her bilingualism later in life. As a result, she often uses her primary language to subordinate the second language (cfr. Two Types of Bilingualism).