S&H: In the same way that basketball and swimming are two very different examples of activities that can be included in the category of sports, there are many different practices that fall under the umbrella term meditation. What types of meditation have been studied seriously and what types haven’t yet? Are there any common benefits to the various types of meditation? Daniel Goleman: So far, mindfulness has been the most studied form of meditation, particularly among beginners. When it comes to long-term meditators—say, more than 1,000 hours’ practice—vipassana or insight meditation and Zen are tops for study. And then, in Altered Traits, we report on an extraordinary group of “Olympic level” Tibetan Buddhist yogis who came to Richard Davidson’s lab for brain studies. TM has also been a frequent target for research, and there have been a smattering of studies on methods like kundalini. But other than these methods, few examples of other varieties of meditation have undergone serious research. This actually leaves out the vast majority of approaches on the family tree of meditation—ev …