I cannot possibly count all of the language learning programs that are available. They vary in teaching methods, course length and difficulty. However, the one that stands out the most appears to be Rosetta Stone. Most have seen this program either in infomercials, online ads, or their local mall. One of the many claims Rosetta Stone puts out is that you will acquire your second or third language the same way as you learned your first, the same way as a child. They like to refer to this as dynamic immersion.
Depending on how you interpret this, the claim appears to be true. You will be bombarded with object and sound associations. For the most part you won’t bother with complicated grammar. You will have a full screen immersed environment in the target language for the ultimate dynamic immersion experience.
Unfortunately, as someone who speaks four languages and has tried this system, I can say that this is not worth the money that you have to shell out. You will not acquire a language the same way as you learned your first language.
The reason is simple. Adult brains are just not wired the same way as children. At birth, a baby has an average of about 100 billion neurons, which have yet to be interconnected together. As the baby grows and becomes a child, These neurons form networks with connections called synapses at a very high pace. Once the child reaches adolescence and soon after adulthood, these synapses become hard-wired and start to complete the neural structure.
It is in this period of rapid connection development when the human’s hearing ability and speed of learning is the most remarkable. Children are still able to pick up native sounds from their parents and learn to speak through mere copying, without learning any grammar whatsoever. Once you become an adolescent and an adult, your brain becomes hard-wired to your native language and the native sounds you first picked up. Speed of language acquisition gets dampened.
Rosetta Stone provides you the environment where you will learn your next language in a manner as you learned your first. However, that doesn’t mean that you will actually acquire it as a child would.
Personal Thought:
Immersing yourself in an environment where you can utilize the target language as well as USING it is the key to acquiring it. But you better know some basic syntax, grammar and rules first. Immerse and use.
Sources:
Wondergressive 
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