Learning More About Meditation and The Default Mode – BionicOldGuy

The default mode network (DFN) is the neuroscience term about the parts of your brain that are active when you are not performing a task, so the brain is “resting”. The problem is that our brains don’t rest in this state, they become active in “rumination” mode which can be unpleasant. So most people are not comfortable just sitting there, they prefer some sort of stimulus like music, video games, social media, etc. I described all this and remedies for it in the previous post Calm Your “Default Mode”. I wanted to learn more about this so I had a chat about it with Gemini. This was with Gemini 3.0 in “thinking mode”, with the deep research tool activated, so it doesn’t just use it’s own training data but does a thorough search for relevant sources on the web.

I was specifically interested in many areas of overlap between descriptions of the DFN and what is called “monkey mind” by meditation teachers. This is what happens to most people when they are trying to meditate. You’re given a basic instruction like “sit upright with your eyes closed, and watch your breath as it flows in and out”. But as soon as you try that, your mind is flooded with thoughts, about the jerk who cut you off in traffic, the rude thing somebody said yesterday, worries about your upcoming tax bill, etc. This behavior of the mind is called monkey mind because it is noisily chattering and jumping around. From what I’ve read this is quite similar to descriptions of the activity of the DFN.

This prompted me to ask Gemini: “meditation teachers speak of “monkey mind”, the incessant chatter we notice in our minds when we try to meditate. This seems very similar to the activity of the default mode network. Is that comparison valid?”. The resulting report is here.

I thought deep research did an amazing job. The answer is mostly yes, with some qualifications. A hyperactive DFN causes restlessness and inability to relax in all of us, and is even more problematic in conditions like ADHD. And meditation techniques to calm the monkey mind also significantly reduce the activity of the DFN, leading to a relaxing feeling.

The qualification is that the DFN still has utility. From the report: “The evolutionary evidence from non-human primates further suggests that the “monkey mind” is a biological reality rooted in an evolutionarily preserved “sentinel” and “simulative” system.” It can help us learn from the past and better plan for the future. But “The “monkey mind” only becomes pathological in the modern human context when it ruminates on non-survival-related psychological threats, leading to chronic stress and unhappiness.” So the idea is not to try to get rid of the activity of the DFN, but to train it and make it a useful helper: “the chattering monkey can indeed be transformed into a focused and tranquil observer.”

Mindfulness and meditation are key tools for doing this, and I’ll discuss my research about them in future posts.

Published by BionicOldGuy

I am a Mechanical Engineer born in 1953, Ph. D, Stanford, 1980. I have been active in the mechanical CAE field for decades. I also have a lifelong interest in outdoor activities and fitness. I have had both hips replaced and a heart valve replacement due to a genetic condition. This blog chronicles my adventures in staying active despite these bumps in the road.
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Published
February 14, 2026February 13, 2026