// preload background images for buttons

buttonSubject0	= new Image;
buttonSubject1	= new Image;
buttonGo0	= new Image;
buttonGo1	= new Image;
buttonRegion0	= new Image;
buttonRegion1	= new Image;

buttonSubject0.src	='/images/leftButtonOff.jpg';
buttonSubject1.src	='/images/leftButtonOn.jpg';
buttonGo0.src		='/images/leftGoOff.jpg';
buttonGo1.src		='/images/leftGoOn.jpg';
buttonRegion0.src	='/images/leftButtonOff.jpg';
buttonRegion1.src	='/images/leftButtonOn.jpg';