The Default Mode Network in the brain
What happens in your brain when you are not actively thinking about anything?
Does it go into a sort of low power, “battery saver” mode in order to use less energy? This would theoretically make sense from an evolutionary perspective.
However, in reality something even more interesting happens.
When we are actively thinking about something, or focusing on something, this primarily uses our brain’s higher order functions such as working memory in the neocortex.
In the 1990s, scientists were experimenting with brain scans and wanted to see which areas of the brain became the most active when participants were focused on a specific mental challenges. They wanted to measure this by seeing changes in energy usage before and during the challenge, and so needed to get a baseline reading of the brain “doing nothing” before the challenge started. In order to do this, the researchers asked their participants to stay still, relax and not think of anything, or just look at a static image.
To their surprise, the difference between the resting brain state and the highly active mental challenge state were much smaller than anticipated. The scientists found that even while a person is resting and not thinking of anything in particular, their brain is still highly active.
Networks in the brain are still working hard and exchanging information when you are not consciously aware of it. There is some “default” activity.
In 2001, summarising years of seeing this activity across experiments, Marcus Raichle coined these active regions as the brain’s default mode network.
Interestingly, the default mode is not in a specific part of the brain, but instead a connection between various different areas of the brain. The brain regions involved in the default mode include the medial and lateral parietal, medial prefrontal, and medial and lateral temporal cortices and the posterior cingulate cortex.
The default network is active when individuals are engaged in internally focused tasks including autobiographical memory retrieval, envisioning the future, and conceiving the perspectives of others.
And when are we most likely to engage in these types of internally focused tasks?
When our mind is wandering.
And mind wandering is good for creativity.
As a result, several research studies have shown that during divergent thinking tasks, there was higher activity in the default mode network. Even more interestingly, there seems to be a correlation between creative performance and the thickness of the brain’s gray matter volume as well the functional connectivity at rest in the default mode network.
One important thing to stress though is that creativity does not “happen” in the Default Mode Network.
Creativity happens throughout the brain, as new connections and associations are triggered. And different brain regions are involved in different types of creativity.
For example, the working memory we mentioned earlier is more involved in convergent thinking. This part of the brain is often called the Central Executive Network, and one of the primary parts of the brain active during this work is the Dorsolateral Prefrontal Cortex.
And there are other networks in the brain, such as the salience network which helps to switch between the default mode network and the central executive network.
But it is interesting to see proof that some of the mental activity you don’t directly control, involved in mind wandering and at the border of the subconscious, is indeed involved in creativity as well.