Here is some more discovery about our brain: it seems that because of some deficit in certain areas in left brain in growing years, integration of hearing and speaking takes place on the right side- but imperfectly. This contributes to stammering; Not just speech, it affects certain other functions also like finger tapping. Read here for interesting details:
What does these findings mean? Give up? NO. To me they mean, accept stammering as it is (instead of saying "it is just a bad habit" or it is all "psychology, negative thinking"..)
and then RETRAIN your brain, attitudes, values, emotions and communication skills..
Remember our motto is: Better attitudes through Knowledge".