Bach, Rachmaninov, Ravel, Michelangelo, DaVinci to name a few, were left-handed! On this assumption alone, using the brain hemisphere division all those theories do not add up :) The aforementioned are proof! Which makes me wonder if you know (or anyone else) if Hitler was left-handed?
There are many sites on the topic.
Here is just one from Google
Right Brain Left Brain -- What's It All About?
The concept of right brain and left brain thinking developed from the research in the ... So if I'm Left-Handed, Does This Mean My Right Brain is Dominant? ...
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