Mind Bending

``I'll never forget my first yoga class," says Simon Voysey. ``It felt like a chemical high but better." A yoga teacher and remedial therapist, Voysey is now dedicated to helping others achieve that natural high. He began doing yoga during the mid-1980s after a naturopath suggested it might help his kidney problems. From his first class he was addicted: ``I thought, `What's this drug?' " He runs his own yoga schools under the banner of Mind and Body. In its eighth year, the school has 12 yo