Cold water exposure led to very rapid increases in norepinephrine and epinephrine, which is also just called adrenaline. It also led to increases in dopamine. And these increases in dopamine were very significant. They kicked in around 10 or 15 minutes after submersion into the cold water—and I should mention the head wasn't below water; it was just up to the neck. And the dopamine release continued to rise and rise and rise and eventually reach 250% above baseline.