I decided to re-publish a great article by Kevin W Chen, Ph.D. who has himself done some excellent research work regarding the effects of Meditation on the Brain.
He says..
There has been an old saying, when Buddha was asked, “What have you gained from long meditation?”  Buddha replied, “Nothing!” “However, let me tell you what I lost: Anger, anxiety, depression, insecurity, fear of old age and death.”  That is a very wise answer, good enough for motivating all of us to start meditation.  However, recent scientific studies of changes in brain images and brain chemicals during or after meditation found that, Meditation can not only quiet your mind and lose all negativity, but also bring significant changes to your brain for better and longer life.  I am preparing for such a study, so I decided to share what I found out in recent scientific literature.
Read his full article here..