Hi Carol, As a piano teacher, I am wondering if playing pieces you know well, the kind you don't have to really concentrate on any more--maybe something at a moderate tempo (which is easier than slow or fast) might give a different result. If you try this, please let us know. See my reply hereabouts re "Mental Exercise". My reserved answer, dependent on further research, is that it is the "excitement" that is the problem. This could be, in the case of piano playing, caused by either concentrating on a difficult piece, or - and here comes the controversial part - by the pleasant emotions generated by a fast, exciting piece. In my own case, I find that composing and orchestrating for MIDI instruments don't affect me much, as I am too busy, but listening to a successful orchestration can turn me into a "whirling dervish". Even solving a difficult instrument transition while having a shower can set me off. Can you imagine the effects caused by a wet body, soap, and dyskinesia all at the same time? <grin> Jim