Meditation is also a great way to stay mentally buoyant, says Richard Davidson, PhD, director of the Laboratory for Affective Neuroscience at the University of Wisconsin. He is studying why some individuals do better than others when exposed to adversity and believes the difference has to do with how the brain, particularly the prefrontal cortex (involved in emotions and memory), regulates negative emotions. Some people are rigged with a genetic advantage, but, says Davidson, the gray matter can definitely be trained. In one of his best-known studies, a group of average Americans took an eight-week meditation course. Afterward, brain scans showed increased activation in their prefrontal cortexes, compared with a control group. "These are individuals who, when adversity occurs, will recover more quickly," says Davidson. "They can't isolate themselves from the adversity—that's impossible. But what can be changed is how they react. And one of the things that distinguishes resilient people from vulnerable people is the extent to which a stressful event elicits a persistent response versus a more acute, short-lived one." As an interesting aside, Davidson's subjects were injected with flu vaccine. The ones who went through the training had a significantly greater rise in antibodies than the nonmeditators. Talk about resilience!