I think that the brain is vastly overrated. (At least mine is!) Woody Allen once said that the brain is his second favorite organ, and I think he was giving it the benefit of the doubt.
What do we do when we think? How can a creature with a brain voluntarily participate in boxing, unless the brain itself is optional? Do cows think, or are they running on auto-pilot?
The ancient egyptians didn't mummify the brain, as they considered it an organ of no great importance. Maybe they were on to something?