My thinking on my 'left tongue' is derived from my limited understanding of the work of Moshe Feldenkrais. Not having studied personally under him I only have second hand knowledge of what he said. I have read several of his books, watched him on several videos. The programs I attended was four years long but only a couple of months each year. I must admit I did not understand him far more than I understood him. He had a book called The Potent Self which I read several times. I am much more the poster boy for 'The Impotent Self'.
However his work in my mind is verified by the finding of my left tongue. He did not address a 'left tongue' but by changing one's perception of body image one changes how the body is used.
Ruthy Alon Movement Nature Meant
This young gal demos and says it much more beautifully than I do. My only quibble would be is that I have two backs a left and a right as I do in the tongues. I feel my left side plays a subordinate role to my right side.