If you want to grow your bicep, you have to place it under stress. And so this is the exact same for the brain. It's interesting because we hear so often that stress is bad. But stress placed upon a certain stimulus in a good way is a good thing. Good stress would be when you go and you activate your sympathetic nervous system by getting your blood flowing. When we're stressed and we're not sleeping and we've got mental stress and emotional stress and that keeps building up, that is the bad stress. That is the stress that turns into anxiety and chronic stress.