A blast from the past March 2009 Scientific American article by Tracy Shors provides a rebuttal to the somewhat common misconception that the brain does not create new neurons. It does – thousands every day. Don’t get too excited, though. If you don’t cognitively exercise these baby neurons, they will disappear within just a few weeks. Article is linked above, but unfortunately there’s a pay wall. I recommend springing for the subscription. It could be your first step in raising a whole new batch of thinker cells.
“Fresh neurons arise in the brain every day… Recent work, albeit mostly in rats, indicates that learning enhances the survival of new neurons in the adult brain. And the more engaging and challenging the problem, the greater the number of neurons that stick around. These neurons are then presumably available to aid in situations that tax the mind. It seems, then, that a mental workout can buff up the brain, much as physical exercise builds up the body…”