As mentioned above the masterful "The Master and his Emissary" by Iain McGilChrist is an in-depth and incredibly well documented look into the nature of the hemispheres (and comprehensively researched and scientifically documented). The fact is the brain does have two hemispheres that are only connected by a relatively small bridge (why on earth should that be the case) and note that the majority of pathways in the corpus callosum are inhibitory pathways. What is true is that many myths do exist about the hemispheres that are false e..g creativity is likely more a FULL brain process than a right brain process (see Keith Sawyer's review of Cognitive Neuroscience of Creativity). Yet the nature of the two hemispheres is very different and nothing could be more true as we do have two brains sitting in our skull which carry out functions very differently. The RSA animation which you can watch on youtube is a brilliant short summary of Ian McGilChrist's book (put in "The Divided Brain" in YouTube) http://www.youtube.com/watch?v=dFs9WO2B8uI

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