In our more recent study, which was published in Proceedings of the National Academy of Sciences, we reported on changes using functional magnetic resonance imaging (fMRI) in brain circuits that are associated with attention. What we show in that paper are robust differences between the advanced practitioners and novices, in circuits that we know from prior work are importantly involved in the regulation of attention. We are continuing to study these practitioners in a variety of other paradigms. For example, one of the things we're studying right now is their response to pain, to physically painful stimuli, since one of the important clinical applications of meditation is among patients with various kinds of chronic medical conditions where chronic pain is a pervasive accompaniment. We're interested in understanding how meditation may alter the brain's response to painful physical stimuli.

DANIEL REDWOOD: In the first chapter of Visions of Compassion, you and your co-authors described your first conversations with the Tibetan meditators, in which they wanted to be certain that your research was altruistically motivated. This is consistent with the core nature of Tibetan meditation, in which meditators focus on compassion for all beings and decreasing suffering in the world. Do you feel that the work you are currently doing marks the early stages of developing a science of attributes like compassion and caring and altruism?

RICHARD DAVIDSON, PHD: Absolutely. There's increasing evidence that this is becoming a real field. There are very serious scientists, some of whom are Nobel Laureates, who are now dedicating their attention to these positive qualities in an effort to give them the attention that I think they deserve.

DANIEL REDWOOD: In Daniel Goleman's book, Destructive Emotions, one chapter included the transcript of a conversation (which you took part in) among a group of scientists and the Dalai Lama that addressed the issue of anger. The participants discussed whether there is such a thing as positive anger, how anger can be controlled or creatively channeled, and also the neurological basis of anger. What can you share with us about those questions?

RICHARD DAVIDSON, PHD: I think it's a very interesting and important theme. There is beginning to be a little bit of work on the neural bases of anger. The prototypical situations that engender anger are situations where we are thwarted from our goals, where there’s some obstacle to our goals. The emotion of anger may have evolved to facilitate the removal of obstacles that are in the way of our goal pursuits. So there may be some positive quality to anger that facilitates action, that facilitates the removal of obstacles to pursuing worthy goals, particularly if the anger can be divorced from the propensity to harm or destroy the person or object that is impeding our goals. So this is something that is just conjecture at this point in time, but there may be this positive quality to anger that mobilizes resources, that increases our vigilance, and in general facilitates the removal of obstacles to pursue worthy goals.

DANIEL REDWOOD: Do the brains of people with depression and posttraumatic stress disorder (PTSD) function differently from those of healthy people?

RICHARD DAVIDSON, PHD: There’s a lot of evidence now using modern neural imaging methods that quite definitively indicates that the functional status of the depressed brain, as well as the brain of a person who experiences posttraumatic stress disorder, is different. There are also some data to indicate that there may be structural differences between the brains as well. Precisely what those differences are varies with the subtype of depression, and this is an area where there is a lot of active investigation. But we know that there are areas of the prefrontal cortex that function abnormally in depression, and there are adjacent areas of the anterior cingulate which have been very explicitly identified as exhibiting abnormalities in depression. In posttraumatic stress disorder, there have been findings that suggest that both the amygdala and the hippocampus—these are two subcortical structures that are very involved in emotions, and that have extensive reciprocity with these prefrontal regions—that these areas of the brain are functioning abnormally in PTSD.