I got a theory. It took us millions of tears to evolve and become what we are today, but lately in the past few thousand years we have made it so far in such a short amount of time that it makes me believe that something happened a few thousand years ago that made us even smarter, i mean it took us millions of years to go from using rocks as weapons to manufacture the weapons, and now in less than a few hundreds of years we went from using horses to ride to cars, planes AND space ships
You are correct. Less than a hundred thousand years ago we developed the pre-frontal cortex. This is what separated up from other mammals, like the ape, and allowed our intelligence to accelerate.
In fact, "teenagers" are a direct result of this development. Before our pre-frontal cortex, what were considered humans were mentally mature by the time they reached puberty. Now, it takes an additional 6-7 years to fill this new portion of the brain with information. Currently we don't consider humans to be mentally mature until they are 18, even though their physical body matures much earlier.
Light reading:
http://blogs.scientificamerican.com/beautiful-minds/gorillas-agree-human-frontal-cortex-is-nothing-special/
