This month, our blog will continue with the theme of how mindfulness can help to change a habit. We thought it might be useful to take a closer look at one of the main components involved in habits, the brain.
First, let’s take a look at what’s going on with this powerful organ when at rest in our skulls. A study done at Harvard in 2010 showed that people tend to think about the future, past, or some place other than where they are, about 50 percent of the time. Our minds wander. During such moments, an identifiable network of neurons becomes activated in the brain. Neurologist Marcus E. Raichle coined the term the Default Mode Network (DMN for short) in 2001 after observing the same network lighting up on functional neuroimaging of people asked to do nothing. The functional neuroimaging, which measures brain activity as it happens, revealed that the brains of people doing nothing were, in fact, doing quite a lot.
Later research showed that the DMN is activated when our minds wander (when we’re caught up in the past or future). Furthermore, neuroscientists have shown that DMN activation is associated with various feelings of discontent. For example, it activates when we ruminate on the past or become anxious about what the future holds. It also activates when we crave something. By contrast, several studies have demonstrated that the DMN becomes less active when a person focuses attention on certain tasks, or when focusing attention on one or more of the senses.
So, it seems that the default settings of our brain route our attention to go to self-referential thoughts of the past or future, including searching for that thing we crave. It might go something like this: I finish a task that took my focused attention. I have some downtime. With my mind focused on nothing in particular, I may think of past situations that made me angry or regretful. Alternatively, my brain may start searching for the next problem that may arise in the future, which quickly results in worrying about future problems I cannot solve yet, or even threats to my future safety. Then my brain searches for something that will make me feel better, something I crave, like a cookie or a beer.
Dr. Jud Brewer, the neuroscientist at Brown University we had mentioned in our last blog post, has studied a specific hub in the DMN called the posterior cingulate cortex (PCC). The work of Dr. Brewer and his colleagues has shown that the PCC activates when people addicted to substances are shown triggers of the addictive behavior, such as a smoker seeing a cigarette or a gambler seeing a roulette table. Basically, the PCC lights up when we’re caught up in craving. After finding this link between craving and the PCC, Dr. Brewer’s lab set the intention of seeing what happens in the craving brain when involving mindfulness. Since mindfulness practices often aim to bolster the practitioners ability to not get swept away by their own thoughts, feelings, and cravings, the researchers hypothesized that mindfulness practices would deactivate the PCC. They compared experienced meditators to non-meditators and found differences in PCC activation, with meditators having “quieter” PCC’s. If you’re interested, you can watch this brief video of Dr. Brewer measuring Anderson Cooper’s PCC activation and deactivation when switching from self-referential, stressful thoughts to mindful meditation.
Later, the research of Dr. Brewer and his colleagues showed that meditation naive people could be trained in mindfulness techniques to reduce the frequency of smoking cigarettes and that this reduction was strongly correlated with a reduction in PCC activity. This finding was not present with an active treatment control group. Subsequently, Dr. Brewer developed a treatment for addiction that teaches people through mindfulness practices to become aware of the actual sensations of the addictive behavior, as well as the cravings in the body prior to the behavior. The mindfulness practices aimed to bring a curious awareness to such sensations with the intention of seeing how the unwanted behavior makes a person feel in real time.
As Dr. Brewer says, mindfulness helps us to not take ourselves too personally. In contrast, the DMN activates when we take things personally (I need chocolate now or I will lose it). Mindful awareness provides us with the opportunity to observe the sensations of craving, being curious about the experience in our bodies and minds (What are the various sensations of “needing” chocolate right now? ), rather than getting caught up the craving itself.
Yet another example of how cultivating mindfulness harnesses this mind/body connection to help us create more meaningful, less reactive lives.