It's not about size

Continuing http://maxim-pr.livejournal.com/288184.html

…Einstein's brain weighs 1230 G, which is less, than the average brain weight of a typical adult male at this age, составляющий 1400 G. In the same work, it was established, that in Einstein's cerebral cortex, the density of neurons is much higher than the average values

http://ru.wikipedia.org/wiki/%CC%EE%E7%E3_%C0%EB%FC%E1%E5%F0%F2%E0_%DD%E9%ED%F8%F2%E5%E9%ED%E0