Meditation and the Default Mode Network of the brain – The Meditation Blog
The Meditation Blog has received several questions regarding the relationship between the so-called Default Mode Network of the brain and meditation.
The discovery of the brain’s Default Mode Network by Raichle et al. (2001) opened new perspectives on the functioning of the brain when we are at rest. Several areas of the cortex, mostly in the association areas, increase their activation when the brain stops attending to demanding tasks. The «Default Mode» of the brain refers to the network of regions activated while we are not engaged in external tasks.
Here we present the questions – and the answers from professor Svend Davanger of the University of Oslo, whose research areas comprise synaptic connectivity in the brain’s Default Mode Network and cortical activation patterns in non-directive meditation. He is also doing voluntary work as an instructor of Acem Meditation.
Top illustration: The three brain scan images to the right show the Default Mode Network during the non-directive Acem meditation technique, while the left three images show the Default Mode Network during a concentration meditation technique.
Q. In scientific studies about the Default Mode Network (DMN), I have noticed that DMN is described as a necessary evil, the activity of which is reduced if one meditates, which is supposed to be beneficial. In contrast, Acem maintains that Acem Meditation increases the activity of the DMN and that this is beneficial. What is correct?
A. It is true that some researchers, particularly a few years ago, held a negative view of the function of the DMN – also called resting state network. They were mainly acknowledged and competent researchers. Today there is little disagreement regarding their research findings themselves. Most researchers in the DMN area today, however, would interpret the results in a different way. There has actually never been any common agreement among researchers that the DMN is a «necessary evil» or that it is associated with a poor quality of life. On the contrary, DMN represents about a third of the cerebral cortex and is one of the three large networks of the brain. If this network had not been good for us, it would probably not have been developed through evolution. Both human beings and mammals use this network for so-called mind wandering, which means a spontaneous scanning or monitoring of memories and future plans in order to be better able to adapt to the world we live in. Matthias Grieder and colleagues wrote in the journal Frontiers in Neuroscience (2018): “The DMN’s integrity appears to play an important role for the health of mind since DMN disruptions have been reported in schizophrenia spectrum disorder, depression, autism, and Alzheimer’s disease.”
Q. Many philosophical and contemplative traditions teach that “living in the moment” increases happiness. However, the Default Mode of humans appears to be that mode of the brain during mind-wandering, which correlates with unhappiness, and with activation in a network of brain areas associated with self-referential processing (Brewer et al., 2011). Some research findings indicate that DMN activity is correlated with poorer quality of life. “A Wandering Mind Is an Unhappy Mind” (Killingsworth & Gilbert 2010). What is the connection between mind wandering and distressing emotions?
A. Based on the same statements from the researchers that are referred to in this question, the connection between DMN and stressful emotions was made the focus of a thorough presentation and discussion in the book «The Power of the Wandering Mind» (Dyade Press, 2019, pp 21-25). Here it is pointed out that, in the study by Killingsworth and Gilbert (2010), the authors show that during mind wandering, the thoughts are more often pleasant (42 % of the time) rather than unpleasant (26,5 %) or neutral (31 %). In addition, other researchers have found that when we at times experience sad emotions during mind wandering, these emotions are present in us before the meditation. It is these emotions that make us think sad thoughts, not the other way around (Poerio et al., 2013).
Q. According to Bauer et al. (2019), while brain DMN activation in human subjects has been associated with mind wandering, meditation practice has been found to suppress it and increase psychological well-being. In addition to DMN activity reduction, experienced meditators show increased connectivity between the DMN and the central executive network during meditation practice (CEN). How should we understand this?
A. This question addresses the relationship between meditation and DMN/mind wandering. An article in Frontiers in Human Neuroscience (Xu et al., 2014: “Nondirective meditation activates default mode network and areas associated with memory retrieval and emotional processing”) provides scientific evidence to support the common experience that during Acem Meditation, the activity level of the DMN is increased, i.e. even greater activity occurs than what is common during ordinary rest. One interpretation of this is that practicing Acem Meditation provides particularly effective rest. This article has had considerable influence: it has been cited by 51 others and has been read on the internet ca 83000 times.
When some researchers claim that DMN activity is reduced during meditation, this is because meditation techniques vary a great deal and have a corresponding variety of effects. Several studies show increased activity in the so-called central executive network and reduced activity in DMN during mindfulness-meditation. The goal of mindfulness meditation, however, is not to obtain relaxation, but rather to be able to focus one’s attention, to be more aware of what is present in the given moment. This may be described as attention training.
This is a somewhat different goal than that of Acem Meditation and other nondirective meditation techniques. The book “The Power of the Wandering Mind”, mentioned above, suggests this definition: “A meditation-technique is defined as non-directive to the extent that it facilitates the stimulus-independent, spontaneous activity of the mind. This is reflected in increased activity of the brain’s default mode network, also known as the resting state network, during meditation.”
The study undertaken by Xu et al (2014) presents the finding that if Acem Meditation is practiced with concentration, in contrast to with a free mental attitude, there is no increased activity of the DMN during meditation. There are many indications that DMN-activity during Acem Meditation facilitates relaxation, stress reduction and working through difficult emotions. Such effects are not the primary goal of mindfulness meditation.
Translated by Anne Grete Hersoug
Language editor: Eirik Jensen