Ray Kurzweil said this quote
“ The intelligence we will create from the reverse-engineering of the brain will have access to its own source code and will be able to rapidly improve itself in an accelerating iterative design cycle. Although there is considerable plasticity in the biological human brain, as we have seen, it does have a relatively fixed architecture, which cannot be significantly modified, as well as a limited capacity. We are unable to increase its 300 million pattern recognizers to, say, 400 million unless we do so nonbiologically. Once we can achieve that, there will be no reason to stop at a particular level of capability. We can go on to make it a billion pattern recognizers, or a trillion. ”