Stammering
I have been stammering as long as I remember, so it would be an act of dishonesty if I do not write my own personal experiences. But I do not have have time to write anything now, still I would like repeat a quote which meant something like this "..compared to what goes on inside stammer's mind, act of stammering is just a tip of an iceberg.." Here are some documentaries & literature of Stammering.

General info
Following BBC documentary will cover this
WrestlingWithWords

Brain & Stammering
http://www.stammering.org/neural_bases.html
http://www.stammering.org/brainresearch.html