Did you guys happen to catch this article from the NY Times? http://well.blogs.nytimes.com/2012/0...***rss&emc=rss
It basically says that DHT produces neurogenesis : ) obviously it's a rat study but promising none the less. I tried to find where the study came from but the article didn't cite the source. Here is a little conclusion of what was found in the study -
Then the scientists examined all of the animals’ brains. They found that, compared with the sedentary animals, the running rats had significantly more of a potent testosterone derivative called dihydrotestosterone, or DHT, in their brains. Even the brains of rats that had been castrated sloshed with DHT.
So the exercise had prompted increased production of the hormone.
Most of the animals also had a plethora of new neurons in the hippocampus, a portion of the brain associated with learning and memory. Unexpectedly, however, the animals in this experiment that could not use the DHT in their brains did not experience enhanced neurogenesis. They exercised just as the other animals did, but their brains did not benefit in the same way.