I once had to do up someone else’s tie and found the only way I could do it was to stand behind and pretend I was putting it on myself. I had simply forgotten which bit went over where, how the loop was formed, and so on. If you asked me how it was done, I wouldn’t be able to tell you, I could only show you. This is because the series of actions had long ago become unconscious and was now a muscular habit, a reflex.
Playing the piano is a bit like this, except it is infinitely more complex! Let’s say a passage from a piece you have been playing for years suddenly goes awry for no apparent reason – perhaps the memory is giving you problems – one solution is to play it cross-handed. The left hand plays the right hand part, and vice versa. Do this extremely slowly, and maybe even arhythmically. Playing this way gives you a completely new experience of the passage, because you are using a totally different series of muscles. You have to think about each and every note, and its relationship to its neighbours – there’s no relying on motor memory. If you can do this, then you know the passage deeply – inside out, back to front and sideways. More to the point, you know you know it! Use this sparingly – it is certainly worth experimenting with, if you can bear it.
There is another practice technique, whereby you create an exact symmetrical version in one hand of a passage you are playing in the other. You match identical fingers and intervals and play the mirror image of the other hand simultaneously. Virtuosos such as Leopold Godowsky believed very much in this way of practising, and Marc-Andre Hamelin also uses it. Listen to him talking about and demonstrating symmetrical inversion practice here, from 3:57 to 6:00
So why does this work? Science has shown us that the right hemisphere of the brain deals more with spatial awareness, with greater sensitivity to motion and distance, while the left hemisphere is responsible for linear functioning. So by practising in this way, we can draw on the strengths of the whole brain. The two hemispheres act together to enable a sort of stereophonic knowledge. The dominant hand helps the other hand, and the benefits are enhanced tactile and intellectual memory, because again you are thinking about every single note in its context. This method is also extremely useful for solving fingering problems. The downside? Yes – it doesn’t sound too good…
Famous pianist and teacher Rudolph Ganz described the technique thus:
It is my belief that symmetrically inverting any difficult technical problem will help the other hand develop equally. Experience with symmetrical practice over the years has been of considerable benefit to me and my students. How often have I listened to the whispered conversation between my two hands: “Difficult?” “Indeed!” “I’d like to try and conquer it too.” “Go ahead. Symmetrically, it is easy. Use the same fingering as mine.” Rudoph Ganz Exercises: Contemporary and Special, p. 12.
Ganz includes in this great book of exercises plenty of symmetrical inversions, including this one of Scriabin’s beautiful Nocturne for the left hand, to be practiced thus in the right:
Here is Chopin’s “Revolutionary” Etude, the right way up:
And here is the mirror inversion of the LH, to be played by the RH: