The Default Mode Network: Lies From the Insular Cortex

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by Dr. C |

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I have written about “the conductor,” a mental construct useful for shifting perspective. The conductor likely has major neural components in a network of areas in the brain: the default mode network, the salience network, and the executive network.

In this column, I will focus on the default mode network and its link to the insular cortex. I believe possibilities for improving outcomes for Parkinson’s patients lie here.

Damage to the default mode network has been noted for Parkinson’s patients. The default mode network is connected to the insular cortex. The insular cortex acts as a switching gate between the default mode network, the salience network, and the executive network. Switching performed by the insular cortex allows sensory input to be evaluated by the desired network. The analogy would be a train that engineers direct down specific tracks to get to the right station — or to avoid hitting other trains! “Hitting a train” equates to us feeling overwhelmed.

Parkinson’s causes damage to the insular cortex. I propose here that damage to the insular cortex, particularly the anterior portion, causes faulty sensory input. Continually using this faulty input will, over time, result in new (but inaccurate) patterns of thoughts, feelings, and actions. These are the lies our brains tell us, which jeopardize our already difficult life with Parkinson’s.

Continual faulty processing in the brain can result in the person with Parkinson’s acting differently. I first experienced this in 2014. I overreacted to a student in class, not being able to control my emotional input in that social situation. It was the first time I did this in over 20 years of teaching. I wanted an answer as to why my brain was acting in a way so contrary to my history.

There is a lot of clinical research on the default mode network. It is difficult to make sense of all the scientific and medical descriptions. Simply put, I label it “our resting mind state.” I think of it as the place where our mind wanders during creativity and brainstorming, or the pause before using the conductor to observe thinking and enter deeper meditation. It is a place where one is mentally quiet so that the mind can function without being constantly interrupted by a stream of sensory input.

I find it difficult to enter that resting mind state when my brain is being bombarded with exaggerated input. I experience this faulty input as surges of exaggerated emotion and other symptoms. We know that damage to the insular cortex affects the default mode network’s functioning. It may also explain my recurring moments of depression or anxiety that I did not have prior to Parkinson’s.

The insular cortex is considered a dopamine-producing center. Why does the brain need it? Parkinson’s patients lose dopamine constantly. I think my frequent use of the conductor helps access sources of this chemical so I can function better with Parkinson’s.

Being able to be a calm presence in social situations was always my strength. That ended with Parkinson’s. Now, I must practice calmness, with exercise, and do so throughout the day. The further the disease progresses, the harder I need to work to show up ready to find the possibility in each day.

Calming down requires daily practice in combination with exercise. I discovered a cleansing effect that combines the two. I can quiet down the insular cortex input. I can find the quiet resting mind. I have failed many times, but more importantly, I have also found that I can succeed.

As I practice quieting down that noisy input, I discovered I need to also relax my muscles. I practice a routine of stretching and massage before and after exercise and sometimes during bad off periods. When I combine this conductor/exercise training with a purposeful life guided by a sacred wellness map, I find something new emerges. I wasn’t just calmer. I was functioning better.

I believe that one of the functions of the default mode network (the conductor) is to instruct the insular cortex to dampen down the input. It buffers the sensory input. It is easier to be more productive and in control of my thinking and emotions when I use the conductor to quiet my mind. In activating this buffer, I believe I am also activating the dopamine-producing neurons. I am not just calmer. Conductor/exercise practice decreases Parkinson’s symptoms that affect quality of life.

Conductor/exercise practice may also contribute to the slow disease progression I experience. I find comfort in understanding what Parkinson’s is doing to me and what I can do to affect the negative outcomes. It is an understanding fitting the running title on my columns: “Possibilities with Parkinson’s.”


Note: Parkinson’s News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The opinions expressed in this column are not those of Parkinson’s News Today or its parent company, BioNews, and are intended to spark discussion about issues pertaining to Parkinson’s disease.


ivan orton avatar

ivan orton

You describe an unfortunately increasing problem for me - controlling my emotional response to what, absent Parkinson's would be minor annoyances (or perhaps not even annoyances at all.) Unfortunately my uncharacteristic "striking back" is not at a student like you experienced, it is at my primary care provider and life partner of over 40 years, my wife. I apologize, often immediately, or occasionally, upon reflection, and she forgives and understands but the cut of my words still stings, I know, and resentment builds up. This is all very atypical of me compared to my pre-PD days.

This happens very frequently (and predictably) at night, as my bedtime approaches. I have described it to her as i feel (and act) like a two year old who is overdue for his afternoon nap. Irrational beyond the pale, over reactive, and childish. This behavior happens at other times, but so regularly, and seemingly beyond my control, at bedtime that we together have concluded that it's best not to tell me anything of importance or remind me of anything during this "just before bedtime" time. I've asked her to, and she has learned to, write me a note, tell me in the morning, etc. That seems to work, but I wish it didn't come to that. I will look at what has worked for you but I fear that the problem is so severe and seemingly uncontrollable that the concentration needed to reach an appropriate calm meditative state might be counter productive at bedtime.

Dr. C avatar

Dr. C

Hi Ivan ~ You have stated this problem in a very eloquent manner. It mirrors my own experiences and some of the same steps my wife and I have taken. I think there are lots of people with Parkinson's diagnosis out there who experience this exaggerated emotional input due to PD brain damage. This input is worse during off periods and it is my understanding many PD patients experience an off period late in the day. It is certainly true for me. Don't give up hope in retaining your brain to manage this exaggerated response. I will keep writing about it.
Thank you for sharing this insightful and meaningful message. Just don't give up -- keep the key piece to put in the "pause between" in any thought or action you take.
Dr. C.

Daniel Novak avatar

Daniel Novak

Ditto for me except that calm was not a top strength before. I had to step out of my volunteer local government role due to emotional reactions.

Dr. C avatar

Dr. C

Hi Daniel ~ I appreciate your comment. Have you been diagnosed with PD? I'd like to hear more about your symptoms and how long before a PD diagnosis did you notice exaggerated emotions? I have written on this topic in a couple of columns and would appreciate your insight to your experiences.


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