Forest Bathing and the Default Mode Network
Updated: Jul 7, 2021
The little fellow above is an American Caesar Mushroom that I met in the forest before the pandemic started. She is considered a choice edible, and often is consumed raw with a little olive oil and balsamic. Even more striking than her taste is her beauty.
I was attracted to the forest because of mushrooms, but once in the forest and familiar with its ambience, I began to hear people refer to forest wandering as, 'forest bathing,' and I began to realize that I was not the only one getting a sense of psychic relief as I wandered in the woods.
Then the pandemic hit. My foraging habits didn't have to change; the forest is a friendly place for those who otherwise would be threatened by crowded human spaces. What changed was that I noticed neighbors and friends attracted to the woods, not because of an interest in mushrooms, but rather, more and more people were beginning to discover solace and a sense of restoration in the woods. The pandemic was encouraging people's resourcefulness; one dimension of their self care being mental health. The woods was answering people's needs and people were responding.
So what does this all have to do with an abstract neuroscience term like, 'the default mode network?' Enter Michael Pollan's recent book, 'How to Change Your Mind,'
In his book, 'How to Change your Mind,' Pollan exploits his disciplined approach to science writing to explore the fascinating landscape of hallucinogens, and their emerging role in the treatment of an array of psychiatric disorders ranging from anxiety, trauma, to addictions. A number of researchers cited in Pollan's book referenced the default mode network as being important in the therapeutic benefit they were observing.
Beginning sometime in the early 2000s a brain scan technique called functional MRI emerged that allowed scientists to look at how electrical circuits in our brains connect with each other during different waking states. Through their studies researchers became aware of a pattern of brain connections that is active when subjects are in a quiet and restful state. They called these connections, the 'default mode network.' (DMN)
It is thought that that the DMN has to do with inner preoccupation. The idea is that when we are stewing over something, like chronic pain, depression, or anxiety, DMN circuits are particularly active. It was also observed by scientists that during brain scans, when people are under the influence of hallucinogens, the DMN quiets down. The DMN is also less active in children, a group who unlike their adult counterparts seem to be more rooted in the present. Which leads us to return to the forest and its pleasant distractions, because functional MRI has taught is that the DMN is quieter when competing perceptual circuits are active. To wit, when we are engaged in something external to ourselves, the DMN is tamed.
Picture a math professor confined to a wheel chair because of disability, who is also in chronic pain, and is also depressed over his plight. A student walks into his office asking the professor to assist with a math problem. The teacher approaches the blackboard and as the equations begin to flow the professor, caught up in what he is doing, is no longer suffering.
A colleague who has considerable experience with psychedelics once told me that the mental states that are evoked by these drugs are states that people can learn to reach independent of the them. That is, psychedelics can help us learn to reach into our minds in novel and beneficial ways.
So back to the forest and the pandemic. It is gratifying to think that during these pandemic times people spontaneously discovered and engaged in a simple activity, forest bathing, and that science has deep explanations for why people found this beneficial.