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3.6 What the Default Mode Network (DMN) and Task Positive Network (TPN) modes of the brain teach us about focus

Last updated: Dec 02, 2022
The DMN and TPN areas of the brain perform different functions. The DMN is active during brooding, ruminating, and other imaginative thought. The TPN is active when you’re focused on tasks. Understanding these different networks can help us understand why our attention often shifts.

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Context recap in this series

In a recent section in this series, “How to move from focus sessions to flow sessions,” I summarized Csikszentmihalyi’s book on Flow and explored how to enter this state. However, I was dissatisfied about the assumptions Csikszentmihalyi made about “psychic entropy” being the natural state of the mind, and I wanted to understand the reasons why. I didn’t uncover any special reason for our default monkey mind other than speculating that our random Internet surfing behavior (or similar behavior to surfing TV) might reinforce the brain with similar chaotic patterns to follow. Compared to this, reading books seemed to encourage a more linear, sequential, and mellow brainwave pattern. After Csikszentmihalyi, I stumbled into another book, ADHD 2.0, that moved forward into more modern science about how the brain works.


Scientists use fMRI to observe the brain in different states, and they found that when the brain isn’t engaged in any particular task, the Default Mode Network (DMN) is active. The DMN was first observed in 1997. Scientists refer to it as the Default Mode Network because it’s the default mode of the brain when you’re not engaged in a task. In contrast, when you’re focused on a task, the Task Positive Network (TPN) is active. (By network, this means there are various regions of the brain that become active, rather than one specific spot.)

In ADHD 2.0, Edward Hallowell and John Ratey explain that the DMN lights up when we’re lost in thought. For example, brooding, ruminating, thinking about future events, dissecting past events, daydreaming, letting our imaginations go free, woolgathering, thinking about worries, going down rabbit holes, and more. When you miss an exit because you’re thinking about what life would be like living on the street after the economy collapses and the Ukraine war escalates into WWIII, that’s your DMN in fully active mode.

Most of the time, the DMN focuses on negative thoughts. And if you keep replaying negative thoughts over and over (negative rumination), you can get stuck deeper in this mode. Hallowell and Ratey say that when you find yourself in DMN mode, you should take advantage of the DMN’s ability to jump tracks (for example, to go down random rabbit holes) by distracting it. The DMN can easily be sidetracked, evidenced by its ability to think about one topic a minute, then another the next, and so on. To exit DMN mode, externalize your thoughts in some other way. For example, focus on your breathing, and breathe in specific patterns. Or go find your pet and play with it. Or look at your environment and observe 10 things you never noticed before. Get outside yourself.

These ideas about the DMN align with Csikszentmihalyi’s psychic entropy. Csikszentmihalyi’s big idea about human happiness was for people to focus on tasks (slipping into the TPN mode) so that the DMN wouldn’t run wild and fill the mind with worries and negative imagination. It’s the DMN that’s responsible for “unfulfilled wants, dashed expectations, loneliness, frustration, anxiety, guilt … [and] the dark side of the emergence of consciousness” that Csikszentmihalyi mentioned” (227).

As you shift into specific tasks, the Task Positive Network, or TPN, activates. For example, suppose you’re fixing your bicycle, writing code, or reading a book—in each case, you’re doing a task. When you’re focused on a task, your DMN recedes into the background and isn’t active. With the DMN locked away, you aren’t burdened by intruding ,negative thoughts. In Csikszentmihalyi’s world, you slip into states of flow and no longer focus on anxious, negative brooding or concerns.

But as soon as you lose momentum on that task and your mind wanders, bam, the DMN becomes active again. Hallowell and Ratey explain:

When you allow your mind to wander from a task, or when you finish the task, or if you pause too long in anger or dismay while doing the task, the TPN in your brain defaults to a different connectome. Not surprisingly—given that we default to this state—this other connectome is called the default mode network (DMN). The DMN allows for expansive, imaginative, and creative thinking. The back half of the DMN—called the posterior cingulate—facilitates your autobiographic memory, your personal history. This allows you to think back, draw upon, and pick apart the past.

The front part, the medial prefrontal cortex, is the opposite. It enables you to look forward and to think about, imagine, and plan for the future. It is in the DMN mode that you can daydream (and miss your exit on the highway) or make interesting connections between concepts (helpful when appreciating riddles or jokes or solving crossword puzzles, or coming up with the Next Big Thing). It was surely in the DMN that the wheel was discovered!

The DMN and TPN are the yin and yang of your brain. Both help us and hold us back in certain ways. One isn’t better than the other. But as helpful as the DMN can be (angelic in its own right), it is also a Demon (as its initialism suggests!) for the ADHD or VAST brain because of our capacity for intractable rumination while captive in it. (24-25)

In other words, the DMN mode is active when you’re not focused on any task, while the TPN becomes active when you are task-focused. The DMN provides more of the imaginative, daydreamy side of your brain, which can have both positive and negative effects. According to Hallowell and Ratey, the DMN is like an angel and a demon at the same time. Angel for the imaginative, creative muse that can give rise to insights, epiphanies, and other realizations. And demon for its ability to amplify negative thoughts, construct dark imagination, and to multiply regret and worry.

For a helpful podcast explaining DMN and TPN networks, see the Angels and Demons (The TPN and DMN Networks) episode of The Attention Seeking Podcast _(

The breakdown of the seesaw

When you’re in monkey mind mode, the DMN is active. When you’re engaged in a task, the TPN is active. In most brains, the DMN and TPN function like seesaws, Hallowell and Ratey explain. When the DMN is active, the TPN is inactive; conversely, when the TPN is active, the DMN is inactive.

The DMN and TPN normally function like a seesaw, with one active while the other is inactive.

People with ADHD can have both DMN and TPN modes active at the same time. There isn’t always a seesaw effect. Further, when the seesaw tilts correctly, there can be a “glitchy switch” between the two modes, the authors say. Someone with ADHD can get stuck in TPN mode, which locks them into a hyper-focused state where everything becomes mute around them. Similarly, they can get stuck in DMN mode, unable to transition into specific tasks as they delve deeper into negative brooding.

With both modes co-active, however, as soon as someone with ADHD starts a task, the DMN distracts them away from the task, pulling their attention elsewhere. The inability to shut off the DMN when you’re focused on a task can make it nearly impossible to focus on the task, as the mind wanders elsewhere and is pulled away by the smallest of curiosities. (ADHD medication focuses on fixing this glitchy switch between the DMN and TPN.) Hallowell and Ratey explain:

To paraphrase Gabrieli, the problem when ADHD enters in is twofold. The first is what’s called the anticorrelation property of the two networks. Imagine a seesaw. In a neurotypical brain, when the TPN is turned on and you’re on task, the DMN is turned off. But in the ADHD brain, the fMRI shows that when the TPN is turned on, the DMN is turned on as well, trying to muscle its way in and pull you into its grasp, thereby distracting you. In ADHD, therefore, the DMN competes with the TPN, which in most people it does not do.

The blessing and the curse vie for top billing, for attention. When the DMN brings lovely images, it is our golden tool. But when it jumps track into the TPN and hijacks consciousness, then the DMN becomes the Demon, the seat of misery, the disease of the imagination. Trapped in the past or future in the DMN, you’re likely to abandon projects you once started with enthusiasm, make careless mistakes, or, worse, fall into a state of misery and despair, for no good reason whatsoever. (25)

Being aware of these two networks seems useful. If you can recognize your DMN taking over, you can distract it and try to reactivate your TPN. It’s also helpful to recognize that the DMN gravitates toward negative thoughts. If the DMN gravitated toward positive thinking, it would be a much more welcome state. I wrote earlier about our negativity bias in reading the news; this negativity bias is the intrigue humans seem to have for the negative over the positive (we slow down to see wrecks alongside the road, but not wildflowers). The DMN also has its own built-in negativity bias, it seems.

Hacks for getting going in the morning

Learning about these networks in ADHD 2.0 was eye-opening for me. Three of the four people I live with have ADHD. Learning about the traits brought me greater understanding and compassion. But also, I started wondering if the key to jumping into more productive, flow-like states was to figure out how to transition from the DMN into the TPN.

In particular, I had a hard time “getting going” on tasks in the morning. I often flittered around a bit, doing easy tasks, before I could get into the rhythm and groove of work. If I could figure out ways to quiet the DMN, or even just to warm up my TPN network, I would have solved a huge obstacle to productivity.

Getting going in the morning
I struggle to get going in the morning. I'm like an old car that needs a lot of warm-up before it can go anywhere

I’ve written a lot about focus sessions and turning off distractions. But what I didn’t find in previous books (such as those by Cal Newport) were techniques for sustaining motivation and getting into TPN mode early. It was common for me to procrastinate on difficult tasks, doing almost anything until deadlines and stress compelled me. How could I get my TPN engine running? Ideally, I wanted to wake up in the morning, list my highest priority tasks for the day, and then immediately start working on them—rather than slowly coming around to them after a couple of hours of reading email, checking the news, browsing the internet, and doing other easy/distracting activities.

For example, after I finished a book I was reading, I wanted to review it but had trouble starting. So to write this post, I tried a simple technique. I started watching 10 minutes of sports. Afterwards, I set a timer and told myself I’d work on this content for 5 minutes. I could do anything for 5 minutes, right? After that, I set the timer to watch another 5 minutes of sports. After that, I set my writing timer for 10 minutes. At that point, I caught a rhythm in writing the content and lost track of my timer. I no longer needed a timer to stay on track.

I haven’t read about this TPN warmup technique, but it’s probably just a spinoff of the Pomodoro technique or an implementation of “The first step is always the hardest.” Just as you don’t start playing full-on competition soccer without warming up first, why not treat the brain in a similar way? Do some light warmups to get you going. I even bought a timer that I could rotate to set a 5 or 15 minute timer automatically, making it even easier.

I also asked my colleague the other week what catalysts she used to get into tasks. She said she finds some aspect of the task that she likes and wants to do, and uses that aspect as a way to get into the task. For example, maybe a documentation task allowed her to learn about something she had always wanted to know. So she would start learning about that thing, and then gradually shift her attention to the less-interesting documentation task.

I felt that the ability to activate the TPN was one of the keys to unlocking productivity. If I could sustain my energy toward my goals, especially getting in TPN mode early and staying there, I knew I’d be unstoppable.


Hallowell and Ratey published their seminal book Driven to Distraction in 1994. In that book, they raised awareness and understanding of ADHD in major ways (even though ADD had been observed since 1902). In ADHD 2.0, the authors assess what’s changed over the last 30 years in the ADHD field and catch up on the topic. Among the list of what’s new is something they call “variable attention stimulus trait” (VAST), which is brought on by “modern life.” When people describe their behavior as “so ADD” or describe themselves as having short attention spans but don’t have diagnosed ADHD, Hallowell and Ratey call this VAST. The authors write:

Beyond the sources of biologically based ADHD, there are a lot of people who act as if they have ADHD but on close inspection turn out not to have the diagnosable condition. These are the people who have ADHD-like symptoms caused by the conditions of modern life. Their “ADHD” is a response to the massive increase in stimuli that now bombard our brains and our world.

The massive behavioral conditioning we’ve all been undergoing since the advent of ubiquitous electronic communications technology has changed us radically. But this dramatic, if not epochal, change is underappreciated. It’s underappreciated because we’re living in it as it happens, like frogs in cold water that slowly gets heated up without the frogs trying to jump out, until they’re boiled. Our world has been getting heated up big-time. And while we could jump out, it’s pretty difficult to do so and still function in the modern world. Most of us can go no more than a few seconds without looking for a screen.

Modern life compels these changes by forcing our brains to process exponentially more data points than ever before in human history, dramatically more than we did prior to the era of the Internet, smartphones, and social media. The hardwiring of our brains has not changed—as far as we know, although some experts do suspect that our hardwiring is changing—but in our efforts to adapt to the speeding up of life and the projectile spewing of data splattering onto our brains all the time, we’ve had to develop new, often rather antisocial habits in order to cope. These habits have come together to create something we now call VAST: the variable attention stimulus trait. (14-15)

In other words, modern life has amplified the amount of information we consume daily, changing our brain’s processors to handle more information in less time. If you recall my initial awakening moment essay, one writer said he became so addicted to reading the news that he started experiencing anxiety due to the massive amounts of information. Rolf Dobelli wrote:

Yet I still felt inexorably drawn to the overwhelming, garish parade of news, even though it was clearly making me anxious. Fragments of news reports were constantly intruding into my reality, and I was suddenly finding it difficult to read longer texts in one go. It was as though somebody had carved up my attention into tiny pieces. I started to panic that I’d never be able to recover my attention span, that I’d never again be able to assemble these fragments into a whole. (p 10)

In my earlier experiments to reclaim my attention, I went through a period in which, following Dobelli’s advice, I also stopped reading the news (as well as browsing social media). I didn’t realize how the news had been affecting me, but I noticed a difference when I stopped. There was less information my brain had to process, and it cleared up more space for reading books. I soon rediscovered reading and how enjoyable books can be.

I eventually returned to reading the news (because I felt so disconnected from what was happening in the world), but I’d never been a news junkie like Dobelli. I glanced through the summaries of The New York Times and ESPN multiple times a day, at most. I also returned to glancing at Twitter, too. These activities, small as they were, strangely provided me with enough information that I no longer felt drawn to reading books. It was weird. I didn’t consider my online intake of information to be that extensive. However, I could unequivocally say that _the more time I spent reading online, the less time I spent reading offline. _It’s as if I had a maximum number of words to consume during a day, and if I consumed those words online, I consumed fewer offline. When I turned the online spigot off, I consumed more content offline.

Why does time spent online discourage book reading? Hallowell and Ratey explain, “Modern life compels these changes by forcing our brains to process exponentially more data points than ever before in human history” (14). In other words, modern life throws a firehose of information at you, filling up your brain’s information sieves. What is it about the Internet’s information delivery that wrecks our brains? Is it nonlinearity? Disjointedness? Fragmentation? Chaos?

In the previous section, I described the possible effects of immersion in the chaos and fragmentation of the Internet, but who can abandon such a resource, or modern conveniences? Critics often blame social media, while Hallowell and Ratey group all of this under the larger umbrella of “modern life.” One can quit social media but … modern life? Not so much. Is the solution to pull a Thoreau to live in a disconnected shack in the woods without internet access?

Coming back to TPN

Coming back to TPN, I wondered whether I could learn something about these DMN and TPN modes of the brain that would make me better suited to the modern condition. For example, if I could flip a switch to activate my TPN, thus muting other distractions, it would be a decent coping mechanism. What hacks could be employed to switch from the DMN to the TPN at will?

Hallowell and Ratey champion the idea that the brain is malleable. Neuroplasticity is another modern finding of the brain, they say (23). The brain can change; it isn’t fixed. They write:

Incidentally, the reason that so many people are starting to look and act distracted, as if they all have ADHD or VAST, is that fewer and fewer people are spending time in the task-positive network. They are not spending enough time focusing on a single task, certainly not long enough to dig a deep enough hole or write an email longer than a sentence or two or do more than look at an egg, let alone fry one. Unfortunately, the TPN is akin to a muscle that atrophies when not used. So as we mentally flit around, the TPN weakens and our attention span shortens. (24)

In other words, Hallowell and Ratey say the fix for VAST is to focus more on tasks to build up the TPN. If we have a weak TPN, it might be because we’re constantly shifting focus, never allowing the TPN to get up to full speed for long-distance cruising. It’s 10 minutes of a task and then bam, checking email, or shopping on Amazon. Another ten minutes of a task, followed by online searches for mundane questions, or seeing what’s new on social media. The TPN atrophies and weakens. Pretty soon, our weak TPN can’t stay active for more than 10 minutes before the DMN takes over.

Balance exercises?

What else strengthens our TPN? Interestingly, the authors say that strengthening your balance can help you focus. Another part of the brain, the cerebellum, has a connection with balance such that strengthening your balance also strengthens your cerebellum, which helps address some ADHD issues. Hallowell relates a touching story about helping a boy in China overcome ADHD by doing things as simple as putting on socks while standing one leg at a time, juggling, and doing other balance exercises (in addition to hugs for Oxytocin). Zing Performance is all about addressing ADHD through balance.

While reading this section on balance, I decided to try some balance experiments. I went to a local longboard shop and got two longboards—one for my daughter and one for me. I figured skateboarding could be interesting and would teach balance in a fun way. In our initial foray on the skateboards, we skated down a small hill and my daughter crashed pretty hard (ripped jeans, skinned knee). After her crash, she was reluctant to return. But I returned to longboarding numerous times, including longboarding for a segment of my commute to work and along a long, flat trail near my house. I started to feel more comfortable on a longboard. It’s mostly a matter of pushing with one foot while balancing on the other. Stopping is also something to figure out (you just drag one foot like a brake).

I also bought a balance board that sits on top of a cylinder (Revbalance 101), which also turned out to be fun. Almost every time I walked by the board, I couldn’t resist getting on and balancing a bit, like some kind of circus performer. I had no way to measure whether any of these balancing tools (either the longboard or balance board) were strengthening my cerebellum and helping me focus better, but I figured it can’t hurt. More than anything, they were fun.


Hallowell and Ratey say other powerful non-medicinal factors for ADHD include exercise, sleep, and nutrition. There are no surprises here—these factors seem to influence many things. But for people with ADHD, getting exercise can help strengthen the connective tissues in the brain. In “Cardiovascular Effects of ADHD Therapies,” Torres-Acosta et al explain:

Exercise has immediate and long-term positive effects on behavioral and cognitive measurements in patients with ADHD (42). The potential benefits of exercise for ADHD are likely due to the increase of norepinephrine, dopamine, and serotonin levels in the prefrontal cortex during and after physical activity (43). Also, brain-derived neurotrophic factors, synaptic proteins, glutamate receptors, and insulin-like growth factors all rise during and after strenuous physical activity, which improves cognitive function by contributing to cell proliferation and neural plasticity (42).

Ahmed and Mohamed (44) conducted an RCT involving 84 students in a 10-week aerobic exercise program for students with ADHD. After 10 weeks, the [subjects] reported that aerobic exercise significantly improved attention, hyperactivity, impulsivity, anxiety, executive function, and social disorders … data indicate that the dose of physical activity for treating ADHD should entail bouts of high-intensity aerobic exercise lasting at least 30 min, at least 3 to 5 times per week…. (863-64)

In other words, physical exercise isn’t just a good idea. It’s like a “dosage” of natural medicine that fixes our internal chemical levels, receptors, and tissues in ways that reduce ADHD symptoms.

My wife’s daily hike had a noticeably uplifting effect on her. She always came back in a GREAT mood, so I encouraged her to hike as much as she could. My youngest daughter played club soccer, and the exercise rejuvenated her.

Hallowell and Ratey even recount a story of a high-achieving professional who, when he had to stop running due to a knee injury, found that his ADHD symptoms (which he didn’t know he had) surfaced in crippling ways and started to dismantle his life. A doctor prescribed him Ritalin to address the issue temporarily. After his knee healed, he dropped the Ritalin and started running again. The issue was fixed.

Given exercise’s potential benefits to the brain, I decided to walk 2 hours a day. Not fast walking or anything, just walking. Being outside. Disconnecting from screens. Getting my blood pumping. Walking made me feel more alive, but I was more interested in the psychological effects walking might bring. Learning to walk involved operating at a much slower pace, moving like a snail for many long minutes. In this way, walking provided a way to reject modern life’s fast pace, to literally step outside of it and reconnect with the physical world. I walked 2 hours a day, for at least a month.

I want to say that walking this long each day was life-changing, but it wasn’t that exciting. I didn’t come back hyper-focused or with increased clarity about my life. I read_ 52 Ways to Walk_ by Annabel Streets. Following the book’s advice, I tried walking in the mountains, in the rain, with zero-drop shoes and hiking boots, walking in the morning, at night, in the city, along the shoreline, and more. I did enjoy walking, but I couldn’t say that it transformed my mental state in profound ways.

Unwrapping gifts

Hallowell and Ratey never reveal a single secret trick to fixing ADHD, and they are not averse to medicine by any means. The findings on medicine for treating ADHD are overwhelmingly positive (see “A 14-Month Randomized Clinical Trial of Treatment Strategies…”) Instead, the overall message of Hallowell and Ratey’s ADHD 2.0 is for people with ADHD to learn to “unwrap their gifts.” There are positive upsides to every negative trait associated with ADHD. ADHD provides “a complex set of contradictory or paradoxical tendencies,” the authors write (7). The authors say:

Of course, it’s true that most people who have ADHD or VAST are really bad at quite a few things (in which their noses get rubbed all the time), but usually they are, or could be, truly exceptional at one or two other activities. Toward that end, we take a strength-based approach to treating people in our practices. As we like to say, we do not treat disabilities, we help people unwrap their gifts. More exuberantly: We help identify superpowers! (63)

For example, in my family, those with ADHD often have positive energy and charisma (an ability to let loose emotionally in fun ways) that draws people to them. The DMN might lead to worry but also facilitate empathy. ADHD people are better at taking risks and excel as entrepreneurs and in the financial markets. Some are adept at processing chaotic situations with lots of incoming data, remaining calm under pressure, etc. One time we had a flood in our house. While I buckled with anxiety, my wife took charge and calmly called in a plumber to fix things.

The authors try to reduce the stigma around ADHD, to get rid of the idea that it’s a learning “disorder” and identify the strengths these traits lead to. The DMN isn’t something to actively eliminate. The imaginative state that sometimes shows a dark consciousness can at times function as an angel.

About Tom Johnson

Tom Johnson

I'm an API technical writer based in the Seattle area. On this blog, I write about topics related to technical writing and communication — such as software documentation, API documentation, AI, information architecture, content strategy, writing processes, plain language, tech comm careers, and more. Check out my API documentation course if you're looking for more info about documenting APIs. Or see my posts on AI and AI course section for more on the latest in AI and tech comm.

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