Yoga is not for all of us. It is for the special ones amongst us. Personally, I excersize yoga to get my body in great shape. Girls like my body and I am not affraid to show off. Some people however practise yoga for mental stability. Or so they say. Bullshit, I say, we all want to look our best and if we want mental stability we smoke herbs.
if you continue your yoga practice, i promise you that eventually your body will awaken the mind. Yoga is a science as well as an exercise.
I started yoga a few weeks ago and I have noticed a decrease in my stress level, but I also definitely agree with the herb thing.
For the most part I think doing any form of exercise will benefit your brain, except for maybe contact sports.