Comment by swores
1 year ago
I can't find free access to the full paper, but here's the abstract (afraid I'm not knowledgeable enough to add to or explain any of it):
"The accumulation of metabolic waste is a leading cause of numerous neurological disorders, yet we still have only limited knowledge of how the brain performs self-cleansing. Here we demonstrate that neural networks synchronize individual action potentials to create large-amplitude, rhythmic and self-perpetuating ionic waves in the interstitial fluid of the brain. These waves are a plausible mechanism to explain the correlated potentiation of the glymphatic flow1,2 through the brain parenchyma. Chemogenetic flattening of these high-energy ionic waves largely impeded cerebrospinal fluid infiltration into and clearance of molecules from the brain parenchyma. Notably, synthesized waves generated through transcranial optogenetic stimulation substantially potentiated cerebrospinal fluid-to-interstitial fluid perfusion. Our study demonstrates that neurons serve as master organizers for brain clearance. This fundamental principle introduces a new theoretical framework for the functioning of macroscopic brain waves."
>Chemogenetic flattening of these high-energy ionic waves largely impeded cerebrospinal fluid infiltration into and clearance of molecules from the brain parenchyma.
Sounds like unsync'd brain waves, (being awake) impedes cerebrospinal fluid flow through the brain.
When asleep, neurons sync their action potentials, acting like a ionized fluid pump, moving old dirty cerebrospinal fluid out, and allowing new, clean in.
Interestingly, when they synthesize that type of ionization using other means, they saw the same increase in fluid movement.
This is my best attempt at translating. Hopefully within 1-2 football fields. The author leaves choice of American or the rest of the world to the reader to decide.
As someone in this field (research field not football field) I'd say that is an excellent layman explanation.
I wonder if these waves also help in “resetting” the distribution of ions among the CSF so neurons will continue to have the proper ion gradients for firing their action potentials?
I wonder if this state could be ultrasonically induced to have a "sleep helmet" which can calm and align rhythmic waves? and induce an artificial flush or "power nap"
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Well, thats basically the trope of every Cybernetic design, with the connectors comming out the back of head/spine...
Like a continual wash which keeps you in this suspended hyper-aware, but calm, rested and focused mental state.
This is why cyborgs have such incredible reflexes.
Have you seen the video on hn a couple of weeks ago about the scientist using ultrasound to halt the progression of Alzheimer’s and to treat addiction?
Most fascinating video I’ve seen in a long time.
Edit: If you haven’t seen it yet, I highly recommend checking it out https://youtu.be/7BGtVJ3lBdE
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I wonder if this could help insomniacs. I had some pretty extreme burn out earlier this year that mentally made it so I couldn't sleep. I had to remove as much stress from life as I could and plan an aggressive routine of not working, relaxation, exercise, sleeping exactly on time and personal therapy with my wife to get my mind to shut down at night.
It is pretty grueling how bad it feels to not sleep so a cap like this would at least make it so the build up doesn't kill you from over collecting old fluid excessively.
I was thinking if we could directly tap and pump fresh cerebrospinal fluid and eliminate sleep
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> Here we demonstrate that neural networks synchronize individual action potentials to create large-amplitude, rhythmic and self-perpetuating ionic waves in the interstitial fluid of the brain
This line is the money shot. An action potential is the variable electrical charge of a neuron, and they maintain that charge by containing a certain concentration of ions relative to the surrounding cerebrospinal fluid. This paper proposes that neurons synchonise their charge state, which forces ions to flow in or out of the neurons in bulk, the movement of these ions causing the cerebrospinal fluid to move around, clearing out the accumulated debris.
I’d expect that it’s probably not the ion movement but the global electric field, maybe even mechanical effects in the axons.
If you look at the Goldstein-Katz equations you see that the conductivities play an as important role as the concentrations.
Most of the voltage change is driven by changes in conductivities and not concentration changes, the ion movements across the membrane should be negligible.
Off course you have the free ions outside the cells than diffuse in a field gradient.
*Goldman-(Hodgkin-)Katz equation
Do these wave of stimulation cause dreaming as a side effect?