What are the negative effects of meditation?

What are the critical components of meditation and what are their concrete effects on the mind and body?

• I'm looking for an organized breakdown of the different aspects of meditation and their impact. This may be different for different types of meditation - I'm curious about all of it! This sort of analysis exists for different excercises - and meditation seems like a sort of exercise for the mind, so I'm looking for something along these lines: "Doing exercise _____ will strengthen the ______ muscle group,  stretch _____, and also work out your cardiovascular system. Working out these areas, this will make ____ (carrying large boxes?) easier day to day, and can make learning to ____ (ski?) much easier." I'd love to see an equivalent analysis for the different aspects of meditation.

• Answer:

  Boy, I could spend all day answering this :) Instead, I'll make a few key observations. First, a disclaimer: "meditation" can mean vastly different things in different traditions and disciplines. Most of my understanding comes from Buddhism and practices spawned largely from it (e.g., secular mindfulness meditation). In this context, the critical component of all meditation is mindfulness. The relevant definition (there are several, depending on which scholar you ask) here has to do with awareness, or knowing where your mind is. As an example of when you might not "know" where your mind is, consider the common scenario of reading a book, only to discover that you're thinking about something else entirely. Until that discovery, you weren't aware of what was going on up top. Refining this quality allows you to notice a huge number of activities taking place in your mind that you may have missed before. For example, it may alert you that you are becoming angry, which allows you to take measures to stop it. It has been said (e.g., by Mingyur Rinpoche) that when there is mindfulness, there is meditation; when there is no mindfulness, there is no meditation. Now for a handful of other qualities that may be developed concurrently. Relaxation. This is a two-way street; it helps for maintaining awareness (consider how it's easier to lose control when overcome with anger), and can be developed using awareness (e.g., noticing and releasing stress). Concentration. As in the book example, you must notice that you're distracted before you can do anything about it. Awareness, in some sense, is noticing. With practice, you can notice distractions before they fully draw you away. Compassion. This is a near-universal trait (possessed by all but a precious few sociopaths) that is frequently suppressed in favor of selfish tendencies. Compassion can be trained directly, but also just shines through naturally as more and more selfish tendencies are seen to be useless or even counterproductive. If developed, compassion has been shown to lead to increased happiness. Creativity. As Prof. Jonathan Schooler recently and wisely pointed out, clever ideas are only useful if you notice them, and more mindful people tend to notice them more frequently. (That said, I've never practiced a meditation designed to improve creativity per se). Anyway, I could go on, but it's late, and I can just point you at Matthieu Ricard's book "Why Meditate." Dude's pretty much a badass, and knows what he's talking about.