Experts now say that laughter lowers stress hormones and boosts the immune system. Optimists may live longer than pessimists. Happy people have more friends, and friendships help shield us from the ravages of disease. Anything that activates this region will increase your level of happiness, and physical exercise is one thing that will. We have found that fine motor components, such as those involved in playing just about any sport, are especially helpful, as is any movement that gives you a feeling of mastery over your environment.
Genes play a part, too.
They were trying to find the cause of her epilepsy, a disorder of the central nervous system. When the doctors touched a tiny part of the girl s brain with an electric probe, she surprised them. What s more, she thought she was laughing for a reason. Patients often remain awake during brain surgery, because the brain feels no pain. However, no one had suspected that a tiny spot in a part of the brain called the left frontal lobe controls laughter.