MIND - A Wandering Mind is an Unhappy Mind (The DMN #1)

This episode is the first of a two-part focus on a specific brain network known as the Default Mode Network (DMN). 

In part one I discuss how the DMN undermines our happiness and our sense of well-being. I make the case that to improve our happiness, we need to recognize when the DMN has taken over our mind and then learn to replace it with a more mindful state-of-mind.

In part two I discuss specific techniques for managing your DMN, activating it when it can be helpful and deactivating it when it makes you crazy.  

Chapters

• 0:00 Introducing the Default Mode Network
• 0:36 Practical Neuroanatomy
• 1:38 How was the Default Mode Network Identified
• 3:59 Your "ME" Network; Functions of the DMN
• 6:52 Theory of Mind - The "Me" of Others
• 8:35 A Wandering Mind is an Unhappy Mind
• 8:56 To Be Happy, Quiet Your DMN

Transcript

A WANDERING MIND IS AN UNHAPPY MIND - DMN #1

Hi. Welcome to the Flourish as You Age podcast. We are exploring ways to use our minds effectively to promote happiness and to flourish as we age. In this episode I’m homing in on a brain network that seems to be the source of a lot of our suffering - the Default Mode Network.  What is the DMN and can we manage its activation in ways that will diminish suffering and amplify flourishing. 

Neuroanatomy is the study of the structure and function of the brain and nervous system. It’s fascinating to know the function of specific brain areas. The hippocampus is our memory maker. The amygdala is activated when we are angry, and so on. 

But this knowledge isn’t always very useful in any therapeutic sense. Knowing that a particular brain network is associated with creativity, for example, doesn’t necessarily help us be more creative. We would have to know how to stimulate or inhibit that brain network and when to do it. 

Fortunately, there is one important brain network that can be managed in just this way. And, it is a brain network that is intimately involved with our sense of wellbeing. That brain network is the Default Mode Network. 

In 2001, Marcus Raichle, a neuroscientist at the Washington University in St. Louis was doing pioneering research to identify which areas of the brain were active during various mental activities. 

As Raichle gathered his data he became confused and troubled by some of the results. When subjects were confronted with demanding cognitive tasks, there were a set of brain regions that became less active rather than more active. It was generally assumed that challenging cognitive tasks would result in heightened activation of multiple brain regions. But Raichle identified, instead, a reliable deactivation of a specific network of brain regions that got quiet when a subject switched from doing nothing to performing a mental task. This network was deactivated when subjects engaged in any kind of task-related activity.  

Raichle described it this way in his 2001 research paper reporting his findings. He says, 

“Whereas cortical increases in activity have been shown to be task specific and, therefore, vary in location depending on task demands, many decreases appear to be largely task independent, varying little in their location across a wide range of tasks (3). This consistency with which certain areas of the brain participate in these decreases made us wonder whether there might be an organized mode of brain function that is present as a baseline or default state and is suspended during specific goal-directed behaviors.”

When the brain focuses on specific tasks, different areas of the brain are activated - different brain networks for different types of tasks. But the same brain network, the DMN, always deactivates - becomes less active - no matter what kind of task the brain is focusing on. 

Now that the Default Mode Network has been identified, researchers have studied it quite extensively. The DMN is now recognized to be involved in a range of important functions. These include autobiographical memory and self-referential processing. The DMN reconstructs memories from your past and strings them together into a narrative description of your life. It creates your stories about yourself.  So, the DMN is instrumental in creating your sense of self. 

When we daydream, the DMN focuses our attention on our selves, not on the external environment. As Dan Coleman and Richie Davidson put it in their book ALTERED TRAITS, “our mind wanders mostly to something about ourselves - my thoughts, my emotions, my relationships, who liked my new post on my facebook page - all the minutiae of our life story.”  The DMN is the Me-me-me center of our brains. Our ego-centric brain.

The overwhelming self absorption also means that the DMN is the source of much of our neurotic behavior. The DMN is associated with rumination, the constant retrieval and rehearsal of uncomfortable memories. And it is also associated with prospection, our ability to imagine scenarios about future events, and to worry about them. 

The DMN is our “monkey mind.” The incessant, self-focused chatter that fills our mind when we are day-dreaming or when our mind wanders. Take a moment right now to experiment with your DMN. Pause, take a deep breath and clear your mind. Don’t think about anything - nothing at all. [Silence] I’ll bet that within seconds, you had a thought or had an image of something enter your mind. It happens to everyone, all the time. This is your DMN at work. It’s job is to think about you, your relationships, your feelings, your failings, your body image - and, unfortunately, it all tends to drift towards self-criticism. 

In addition to building a sense of our self, the DMN also recognizes that other people have selves as well. Other people have monkey minds of their own. They have unique thoughts and feelings that are hidden from us. We can’t hear the voice in their head, which is troublesome, worrisome. What are they thinking? Is their voice evaluating me just like my voice is commenting on them? Probably so.  

Unfortunately, the stories spun our DMN tend to make us suspicious about the motives of other people. When day-dreaming our DMN ruminates about our past actions and replays uncomfortable interactions with other people. The DMN also creates worrisome scenarios about future interactions we will have with people so we get to be anxious about things that haven’t yet happened and may never happen. Rumination, regret, shame, anger, jealousy, paranoia and so on, all are stimulated by the stories our DMN invents. 

The DMN is the source of our neurotic behavior. When we spend too much time day-dreaming, and when we make the mistake of believing all of the bullshit our DMN is telling us, we get all neurotic and full of anxiety.

 Dysfunction of the DMN has also been implicated in various psychiatric and neurological disorders, such as Alzheimer's disease, autism spectrum disorder, and depression. 

Harvard researchers had thousands of people record their mental focus and how they were feeling at random points throughout the day. The researchers concluded that “a wandering mind is an unhappy mind.” So, it is clear that to be happy - to flourish - we need to do a better job of managing our DMN. 

We need to activate the DMN when it can be useful for use and we need to know how to tell it to shut up when it is messing with our minds and making us crazy. Do we know how to manage our DMN? I think we do. I’ll discuss techniques for managing our DMN in the next episode.   

Until then. Keep well. Take care of that lovely mind of yours.