The Default Mode Network

A short review of different claims about the funciton of the DMN

The Liminal Coaching View of the Default Mode

Research by Alvaro Pascual showed that focusing on a particular scenario caused more and more neurons to be repurposed to that task. So negative rumination will repurpose neurons to that task also.

Negative rumination can create as much stress and anxiety as actual events.

This can snowball into a vicious circle and contribute to depression.

That’s how bad compulsive, negative internal monologue can get, and the DMN has come to be associated with that miserable state in some circles.

But it really isn’t as simple as that.

The DMN is active in rumination, but not only then. It also seems to switch on in a certain mode when we do deep visualization and scenario creation with our imagination.  That doesn't mean DMN causes negative rumination any more than my TV set being switched on means it is responsible for a show’s content.

I'd love to see DMN scan results for people doing focused, positive visualization or in positive guided relaxation.

A lot of findings about the DMN are presented as far more definitive than they really are, leading to the impression that somewhere, someone has more than an inkling about what it’s doing. Then again, it’s tough to write engaging copy that is peppered with so many caveats that the reader can be forgiven for concluding there are no results at all.

 Here are a few examples.

This is an interesting and fun video with Dr. Beau Lotto (Professor of neuroscience at Goldsmiths London and at the University of London) on how awe results in the DMN switching on and people being more right-hemisphere focused:

Then there’s Social Neuroscientist Matt Liebermann (Professor of Psychology at UCLA) claiming the DMN is only for social thinking: at 10 minutes

He doesn't explicitly say DMN in this short video but does in his book “Social”.

In his best-selling book “Cured” on page 271, Jeffrey Rediger, MD, MDiv (On the faculty of Harvard Medical School), defines the DMN as “the blueprint of the building you’ve been conditioned to think of as you. Your life, your identity, your sense of self, your story, your method of operating in the world – it’s all built on this blueprint.”

There is not much in the book describing how this conclusion is reached, but it is fashionable given the correlation between DMN activity and self-referential processing.

It has also been linked to depression as if it were causative when, in fact, there is only evidence of correlation.

That hasn’t stopped those deeply enamored of the use of psychedelics in treating depression from seeking to establish that a reduction in DMN activity during the use of psychedelics is the mechanism responsible for the very effective reduction of symptoms that psychedelics certainly produce. It’s understandable as they seek evidence to support wider legal use of what is clearly an effective treatment, but it again confuses correlation with causation.

So, interestingly, right now, the DMN is being positioned as responsible for a number of different things.

I think it is a general-purpose complexity-processing capability in part and probably has a lot of other functions as well. Certainly, it turns on during REM sleep and is implicated in memory processing.

There is evidence for on-demand reconfiguration of not just the DMN but other large brain networks:

“We interpret these results as a demand specific network reconfiguration of the DMN: a decoupling of the mPFC to support schema memory and a decoupling of the parahippocampal gyrus facilitating episodic memory. This supports the notion of dynamic reconfiguration of brain networks in response to task demands in the sense of process specific alliances.”[1]

My own take (based on theorizing to most inclusive simple explanation) is that it is somewhat analogous to general-purpose computers. In other words, it depends on what you run on it as to what it does, and it depends on which of many possible functions or configurations are utilized.

In addition, research has identified a number of other large brain networks, including the cerebral cerebellum network and the Semantic Network. In the past few years, research in Israel has identified that all 3 of these networks work together during creative insight, the process of selecting the elements from a sea of creative possibilities that will work for what you want to do.[2]

So, in Liminal Coaching, we use states of deep relaxation (that we call liminal states) and metaphor to do what I see as stimulating a particular kind of symphonic brain activity.

Of course, I don’t have the huge sums necessary to conduct fMRI or even reasonable EEG studies to begin to support this model in the reductionist paradigm of proof,

So I rely on the approach of combining that amount of best science I have the bandwidth for, abductive reasoning, what I can see working, and the ever-present knowledge that it is all metaphor anyway. If you delve deep enough into any evidence-based scientific statement, you will always arrive at imponderables and the limits of the current metaphor.

My main thought about most of this type of research is that it shows a really interesting and suggestive correlation that then gets conflated with implied causation in most of the thinking and presentation around the results.

In my experience with clients, repeatedly having them build the scenario of their preferred future and what better looks like before using guided relaxation (DMN activated) for re-patterning has the corresponding effect. A kind of deliberately engineered positive rumination, if you like.

I think the DMN is a much less defined, permanent kind of thing than many seem keen to infer from the scanning snapshots available so far.

I also believe that the DMN is not a constant symphony of just selected brain regions, but regions activated and included in the network may differ, and the degree to which they are engaged may differ, so I think the suggestion that DMN is composed of these areas of the brain always linked in this way is really misleading.

I think the term itself is a reductionist attempt to freeze and explain the systemic, holistic operation of the brain from a few sets of interesting experimental results, which suggest to me a vast field of systemic resonant possibilities. I do not doubt that different forms of systemic resonant interlinking across different brain areas is correlated with and possibly partly causative of an infinite number of different states of mind.

The Liminal Coaching view is that the DMN is a powerful creative and patterning mode of brain operation that is capable of multiple results depending on how it is programmed by what we focus on and what we are trying to do at a given point in time.

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[1] Medial prefrontal decoupling from the default mode network benefits memory

View ORCID ProfileN.C.J. Müller, View ORCID ProfileM. Dresler, G. Janzen, View ORCID ProfileC.F. Beckmann, View ORCID ProfileG Fernández, View ORCID ProfileN. Kohn

doi: https://doi.org/10.1101/706051

Now published in NeuroImage doi: 10.1016/j.neuroimage.2020.1165

[2] Work done by Ben Shofty, Tal Gonen, Eyal Bergmann, Naama Mayseless, Akiva Korn, Simone Shamay-Tsoory, Rachel Grossman, Itamar Jalon, Itamar Kahn & Zvi Ram  in Tel Aviv produced evidence to support a causal link between DN and creativity.

Department of Neurosurgery, Tel Aviv Sourasky Medical Center and The Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel

Article in Nature January 2022:  https://www.nature.com/articles/s41380-021-01403-8