I think you should start on a broader note and then narrow it down to a specific incident in your life thats relevant with the thing you are applying for... Like lets say you were good at arts when you were young...but growing up you started linking arts to science and then pursued engineering or some other thing...
A story of your life could also start off with a specific incident that totally changed your point of view about how you see things in life...how your perception altered.
I really like this idea of introducing a new concept...Gives your Statement a certain edge to it. However trying to comeup with ONE word to describe what you want to is rather difficult. Im trying to comeup with something for my SoP (statement of purpose)...Im an engineer whos an artist as well...Warring religions, i know!