I don't know what is actually behind this condition, but I can tell you this much. I suffered from this starting at about age ten, and this continued until I was twenty. I suffered from severe allergies and asthma until I began allergy shots when I was seventeen years old. After my daughter was born ( I was 21) I went on the birth control pill for three years. During that time my episodes of sleepwalking stopped and the talking in my sleep lessened. I don't know if it was lack of oxygen or hormone imbalances or maybe a combination of both. That lasted until I hit my thirties then I began talking in my sleep again, although not as bad as when I was young. About two years ago I found myself waking up in the livingroom, bathroom or kitchen and not remembering getting up and going there. It didn't happen often, but because of this happening when I was young I became concerned. There was a lot of emotional stuff going on in my life then too, so who knows. Maybe it was the overload working on me. The reason I am telling you this is that when I went through menopause, I began having problems again. Coincidence? Perhaps. I started using natural progesterone in a transdermal cream just over a year ago because tests showed that all my hormones were dangerously low and I would not take the HRT form of hormone treatment. The episodes lessenen and have now stopped, plus I sleep most of the night. I still have the same problems in my life which esculated when my sister died a few months ago, but I am not sleep walking or talking out in my sleep now. When I researched progesterone I learned that it is found in large concentrations in brain cells. Perhaps you can learn more on the net about this yourself. I think there is a connection, at least it was in my case.