Knowing DMN well: The Emissary and the brain's default mode network

Have you heard of the default mode network? It's relevant to three Emissary characters' mindsets. Lately, there is not a single day that goes by where I don’t catch myself. DMN! There I go again! DMN stands for default mode network. I have developed a new habit of catching mine running overtime. It’s a relief. I catch my DMN running, and bring my attention back to the present moment. It is a good exercise. I’ll describe what the DMN is, in more detail in a bit. Thanks to functional MRI, the DMN is is a hot research topic these days.

In the novelization of the Emissary, three main characters' mindsets are crafted to portray how getting stuck in the past, future, or the present each come with their own version of disability.

I’m writing the Emissary novel. If you have seen the movie, you'll know the underlying theme: practicing being attentive to the present moment rewards and enriches our lives. This is true even if the present moment is unpleasant and our world is about to "blow up". But one point I am also trying to make is that it is not “bad” to not be present, either.

It is all a matter of balance. The process of being aware of what you are doing—thinking about the past, present or future—and doing it consciously, being able to move from one state to the other at will, that is the skill that is worth exercising. It is about not getting stuck in the past, the future, or even the glorious now.

Tim Erskine, the director of the Emissary, creator of most of the Emissary script minus some edits and scene inserts of mine, is conveniently also my husband. I’m frequently consulting him about how to slip in the more meaningful themes of the book in practical, non-preachy, entertaining ways that work with the storyline. As he sips his morning coffee he asks me this question:

     “Is this default mode network bad?”

     “No..." I pause in the middle of my yoga stretch to consider. “…not at all. Without a default mode network I think you would end up like my mom.”

My mom has dementia. She can not remember how to put her clothes on, how to read, how to write. She is always in the present moment. She is generally often very happy, too, and I don’t know if the two things are related. I may just be lucky to have a happy mom, because lots of people with dementia are not happy. But as happy as she is, she needs a caregiver to dress her and cook meals for her and to give her medications on time. She could not survive without constant care, and as with caring for a baby, it is exhausting work. I feel guilty that an afternoon with her completely wears me out.

When she apologizes for all I do, I joke with her: I always wanted a little girl. I just didn’t know she’d be 79. Every time I use that line she laughs, because each time she’s forgotten the punchline.

I imagine one appealing activity in having a little girl would be to read to her, and share stories. My mom used to love reading stories to me, and when I grew up we enjoyed sharing book recommendations. Now she can barely follow a few sentences at a time. Her memory won’t allow her to enjoy stories anymore. This breaks my heart. You need your DMN to appreciate stories.

I try to remind myself that the important thing is that she is happy. Everything is salient to her. She notices everything, like a child. The trees! The flowers! The noises! It is wonderful and exhausting.

The DMN is a network of interacting brain regions (posterior cingulate cortex, precuneus, medial prefrontal cortex, and the angular gyrus). They get busy talking to each other when we go on autopilot. When we are not attentive to what we are doing, the DMN takes over.

When the DMN is active, people are daydreaming, mind-wandering, thinking about others, thinking about themselves in a narrative sort of way, remembering the past, planning for the future, imagining what other people are thinking or planning (the ability to imagine what other people are thinking and feeling is called theory of mind.) We need the DMN to imagine what other people are going through. The DMN is required to understand a story. Problems with the DMN appear to occur in autism, ADHD, and certainly in the neurodegenerative diseases that cause dementia. A hot research topic, indeed.

What is the DMN? (2 min video)

Brain networks concerned with attentiveness compete with the DMN. If you want to put your DMN on pause, just ask yourself: what are you smelling, seeing, touching, tasting, hearing, right now? That generally does the trick for me. Some people practice establishing a specific go-to DMN interruptor, like focusing on the sensations coming from their right big toe, for example, or the sensation of tension in their face or jaw.

It is all about balance.
So, when my mind cycles back to what documentation I need for my mom’s Medicaid renewal, how to electronically send it to the Medicaid agent, what I should write on the forms in order to explain them, I am using my DMN. That is fine. This is necessary. But is it really necessary for me to have the same thought about completing this paperwork twenty times in an hour? How about just twice? Twice might work fine! Not twenty times. Having the exact same planning thoughts twenty times in one hour makes me cranky! That’s what sticky notes and journals are for, right? (See my post on the benefits of writing things down.) Balance.

Andy, Mark, and Jim from the Emissary represent the past, future and present.
Mark (played by Pat Palmer), the bookstore owner in the Emissary, is always worried about the future in my book. He is disabled by anxiety. Andy, hapless entertainer and sufferer of chorus neurosa, a made-up disease we invented, where he repeats what people say whenever he is nervous (played by Paul Erskine) is morosely ruminating about his past failures. He is disabled by depression. Jim (played by Tim Erskine), the central character, is so keen on teaching people to be in the present moment—which he isn’t able to do very well anyway—that he is obliviously annoying to his friends. They tolerate Jim with the loving patience that only longtime friends can sustain.

Killingsworth and Gilbert’s research article, A Wandering Mind is an Unhappy Mind, bounced energetically about the media after it was published in Science in 2010. (I discussed the details of this study in Embracing that Awful Chore). Basically, they found that when people are doing anything, even when they are doing something unpleasant, they are happier if their minds are on the task, rather than wandering. It was a surprise to find that people doing unpleasant things were not happier if their minds were wandering.

I would suggest that if you must focus on an awful chore, try re-framing it in your mind. Imagine that it is what you've always wanted to do. Find a way.

The authors concluded:

“In conclusion, a human mind is a wandering mind, and a wandering mind is an unhappy mind. The ability to think about what is not happening is a cognitive achievement that comes at an emotional cost.”

My take: It isn’t that being in state A or B is better. It helps to learn how not to get stuck in either one. This is as easy as being aware of your mind state on a regular basis. Being able to switch from DMN and attentiveness, or from attentiveness to the DMN, at will; that is the muscle worth strengthening.

Homework:
Randomly through the day, ask yourself if you are in your DMN. If so, that’s fine. It is necessary, remember. But it is the noticing that is helpful. Try bringing yourself to the present moment by concentrating on all your senses, and see how that feels, in comparison.

Additional links:

Dan Harris talks about meditation and the DMN (4 min)     

Nobel Laureate Phillip Sharp talks about why some answers are revealed only when we are mind-wandering. (2.5 min)     

Cognitive neuroscience of mindfulness meditation and attention lecture, (48 min)