Normally stress is a nasty experience, but not at low levels. At low levels it thrills. A nonthreatening stressor or challenge, like a sporting match, a fast drive, or an exciting market, releases cortisol, and in combination with dopamine, one of the most addictive drugs known to the human brain, it delivers a narcotic hit, a rush, a flow that convinces traders there is no other job in the world.
