I seem to recall reading somewhere that most of our brain is just interior "wiring" and the actual thinking goes on in the outer few millimetres - i.e. most of

I seem to recall reading somewhere that most of our brain is just interior "wiring" and the actual thinking goes on in the outer few millimetres - i.e. most of the brain is just interconnections. If that is correct then I would expect that the amount of "wiring" (and so overall volume) would need to increase exponentially as the brain power increased. ...plus there is all that crap about us only using 2% of our brains etc.