Brodmann Area 47, in the prefrontal cortex, is the brain area that most specifically characterises meditative activity, but only in techniques using an open, relaxed focus of attention.
Imagine yourself lying in the grass in the forest on a pleasant summer day. You feel the warm wind, the grass tickling your legs, you hear insects buzzing nearby, you see the sunlight shining on millions of green leaves in the branches overhead. You experience a thousand little things all around you.
Then change the scene: You are now at work, preparing intensively for a meeting with your boss and several customers in an hour’s time. Co-workers try to stop by for a chat, your phone receives text messages, and it is raining outside the window. But you are not aware of any of this; you concentrate solely on the task in hand, excluding almost everything else going on around you.
Two types of meditative attention
These are two opposite modes of mental activity, and they also resemble different modes of meditative attention. Many meditation techniques are reported to use active concentration as an integral element, with an intense and exclusive focus of awareness. Other types of meditation, by contrast, use a relaxed, inclusive type of attention.
How does the brain handle such different types of meditation? And in what way do their effects differ? Such questions have been at the forefront of ongoing studies by a small group of Norwegian medical scientists during the last few years. They have recently published a study on brain scanning during Acem Meditation in the journal Perceptual and Motor Skills (Davanger et al., 2010). The study shows that some areas within the prefrontal cortex (the part of the brain that lies just behind the forehead) are activated more strongly when meditating with a relaxed focus of attention than with a more concentrative frame of mind. The prefrontal cortex is an important part of the brain, receiving information about what goes on in most other brain areas, enabling us to reflect and decide, at any given moment giving priority to some mental tasks while inhibiting others. Forms of meditation with an open awareness seem to stimulate these functions more strongly than meditation with a narrower and more exclusive focus.
It is also interesting to note that the brain activation involved does not decrease with time, as is normally the case with other mental tasks, but becomes stronger in longer periods of meditation than in shorter periods. In other words, the relaxation achieved in such forms of meditation does not seem to be the result of habituation, of the gradual weakening that usually takes place with continuous or repetitive stimuli. Instead, meditative relaxation seems to be accompanied by activities of the prefrontal cortex that increase in intensity during the meditation period.
Considerable scientific effort is now directed towards determining what factors may produce a healthy and efficient brain in ordinary people. One interesting line of research focuses on the effects of meditation on brain structure and adaptability, or plasticity. In this context, it is highly significant that meditation with an open, inclusive mode of attention towards the meditation object appears to activate the prefrontal cortex more strongly than meditation with a more concentrated, exclusive form of attention. In many everyday contexts, the ability to concentrate is necessary to achieve good results. In many forms of meditation, however, better effects seem to follow from a more relaxed frame of mind – much like lying in the grass in the forest on a pleasant summer day.
Svend Davanger, Are Holen, Øyvind Ellingsen and Kenneth Hugdahl (2010): Meditation-specific prefrontal cortical activation during Acem Meditation: An fMRI study. Perceptual and Motor Skills: Volume 111, Issue , pp. 291-306.