Already the premiss goes wrong with "The human brain is a fascinating machine."
The human brain is not a machine and we have not been able to outperform its capacity by any means. I'm hopeful we are not on any intelligence plateau. Resources and knowledge prior to Google et. al. have been restricted to a happy few. We are propelling innovation forward at an accelerated pace and it is an awesome time to be a live. Lets stop with the limits questions and lets break more and more and even more barriers other people have thought to be impossible.