Musician Plays Violin as Surgeons Operate on His Brain   Roger
Frisch of Plymouth, Minn., lay on the operating table with his
hands clutching his violin to his chin. While surgeons operated
on Frisch's brain, Frisch began to play the chords he's known
for more than 30 years.  It seemed like a scene from a science
fiction movie. But every note he played told the surgeons
whether the electronic pulses they were sending to his brain
worked to ease his body's tremors.  In June 2009, doctors
diagnosed Frisch with essential tremors, a condition that occurs
when sections of the brain that control movement start sending
abnormal signals.  Nearly 10 million Americans suffer from
essential tremors, according to the International Essential
Tremor Foundation.  VIDEO: Daily Download (3.19.10) Fiddling
With the Brain  The condition most often affects hand movements,
and simple tasks such as drinking a glass of water or eating
become difficult. But for Frisch, a concert master with the
Minnesota Orchestra, his right hand sh