Review Symptom perception in adults with chronic physical disease: A systematic review of insular impairments 2024 Riegel et al

Highlights

• In chronic physical diseases, insula has lower volume/density and abnormal activity.
• There seems to be a positive trend between insular activity and symptom severity.
• This study can help explain poor symptom perception, improve care and patient outcomes.
• Interventions targeting the insula can improve body listening and symptom management.

Abstract

Background
To perform self-care, individuals with a chronic illness must be able to perceive bodily changes (ie., interoception) so they can respond to symptoms when they arise. Interoception is regulated by the insular cortex of the brain. Symptom perception is poor in various physical diseases, which may be associated with impairments in the insular cortex.

Objective
The purpose of this study was to explore whether patterns of insular impairment exist among adults with chronic physical diseases and to analyze the relationship with disease-related symptoms.

Methods
We identified studies that assessed the structure and/or activity of the insula through MRI and/or (f)MRI in adults with chronic physical diseases (vs. healthy controls) by searching five databases. Results are reported as a narrative synthesis.

Results
Fifty studies were conducted to investigate the structure or activity of the insula among adults with diabetes, cancer, heart failure, or chronic pulmonary disease. In 19 studies investigators found that patients with a chronic disease had lower/damaged insular volume/density/thickness than healthy controls or reduced insular blood flow. When insular activity was explored in 22 studies, most investigators reported higher insular activity and lower neural connectivity. Five studies explored the association between insular volume/activity and symptom severity: four reported a positive trend.

Conclusion
People with chronic physical diseases have lower insular grey matter volume/density/thickness and abnormal insular activity when compared to healthy people. Insular activity may be related to symptom severity. These results suggest that insular structure and/or activity may explain poor symptom perception.

Open access, https://www.heartandlung.org/article/S0147-9563(24)00211-5/fulltext

 

The volume of research that can genuinely be described as "they're totally screwing with us here are they?" and "Shirley, you can't be serious here" just keeps growing and growing. Even the background is just so damn weird. If you told me that this was written by aliens trying to pass as humans I would totally find it plausible. And if you'd told me it was written by an AI, I would assume it's an older model because the new ones are so much better at passing for humans.

Here's an idea: let's just plug disabled people into some advanced virtual reality setting where our entire life experience is controlled to make us feel like we are living in a tropical paradise free of worry and illness and sadness and so on. Then we could, I don't know, harvest our energy, or use our brains to make computations, or whatever. This way we get the double benefit of pretending to help us, while achieving the only thing that seems in mind when it comes to disability: put us to work.

Medicine nowadays is as weird about symptoms as Gandhi was about bowel movements.

Either this or the Matrix:

 

Explaining why this paper is ‘not even wrong’ feels like it would make me dumber.

Perhaps that is analogous to why interception may be dulled in chronic conditions. Repeatedly engaging with negative stimuli which cannot be resolved serves no purpose but creates stress and frustration.

 

Cause or effect?

What they are writing is quite misleading. There is no generalised interoceptive impairment sense and any differences in sensation are specific to the illness/syndrome

This is just vague woo.

 

More than vague, this is weird. The "produce neuroplasticity effects" framing where they usually mean "changes the brain connections" is weird, but it's also generically weird. Aside from doing nothing, everything seems to do that, from education to bullying or even daydreaming. So who decides which change is good vs bad? Based on what knowledge about neural connections? Absolutely none, of course. So that judgment is based entirely on the behavior itself, while pointing to some generic change that no one has any means to validate whether it can even have a meaning as being good or bad.

Meditation and exercise, changes neural connections, good. Addictive behavior and drugs, changes neural connections, bad. Not based on any actual knowledge about which changes do what or whether they are "good" or "bad", it's completely arbitrary based on the behavior itself. It's similar to how some people judge other people's behavior not based on the behavior but on who the person is. Person they like did X? Oh that's fine, boys will be boys or whatever. Person they dislike did X? To the gallows! Have to teach a lesson for the others who think they can get away with X!

But the entire literature is still this vague hopey changey "may improve" or whatever. Always vague potential that is assumed to be good... just because. No other reason. If we notice changes in neural connections from playing a lot of chess, that's great! If we notice similar changes because someone plays video games as much as a chess player would need to become a master, ooooh that must be bad!

And also mindfulness engaging executive function? When people say mindfulness 90% of the time they just mean meditation and if there's one goal to meditation it's precisely to quiet that executive function for a moment. So that's just generic arbitrary "could be of help to some people" but they can't even define what any of the individual factors even mean.

Just weird mumbo jumbo but it's taken seriously by nearly the entire profession, and they still can't make any more sense than just throwing scrabble tiles on the floor.