Surprisingly complex waves reveal the brain's inner workings

Bit of a sensationalist title - EEG/iEEG measurements have led to worthwhile clinical outcomes but also are an avenue for bunk pseudosccience so it pays to be careful whenever you see the words 'brain waves' paired with some large claim.

More accurate, much less sexy title: Intracranial Recordings Uncover Spiral and Concentric Brain Waves During Memory Tasks" (study completed only on small cohorts of epilepsy patients performing constrained memory tasks).

No inner workings revealed or laid bare, just another piece of evidence contributing to a small part of the debate in cortical electrophysiological studies on whether or not some data measures can be discarded as the downstream, messy noise of the neurons firing or actual, high-fidelity signals of activity

For context, the debate in the field has been whether these are epiphenomena of the actual neuronal activity, or a meaningful driver of further activity.

I don’t think these studies quite rest the case. As Buzsaki comments in the article, the action is in the cells to create these waves. Do the waves themselves get measured and impact what happens next? The issue at hand is: synaptic currents are stronger and we know neurons respond to them. The wave behavior is in the extracellular fluid as well, and that part we have evidence neurons don’t respond much to.

That said, thing the article doesn’t talk about is astrocytes. Especially in the cortex, most synapses are tripartite. There’s an astrocytic end foot that sheathes the synapse and regulates how much of the bulk extracellular space has access to the synapse. And one astrocyte can touch thousands of synapses and in humans, hundreds of thousands. They also form a syncitium, through gap junctions/electrical synapses.

Do astrocytes respond to the extracellular wave behavior, which potentially changes the extent and behavior of the syncitium, and thus impact the neurons they touch?

That’s still an open question but that’s what I’d be interested to find out more about.

It’d be interesting to try and model the various waveforms observed as time crystals and see if the mathematics of the latter can (partially) predict the former.

> Surprisingly Complex Waves Reveal the Brain's Inner Workings

From my ignorant point of view I can't quite make sense of the title. Brain is probably the last organ one would be surprised to find complexity in. I can see "surprisingly complex wave reveal spleen inner workings" being a good title, like "wow, we though it was a dumb blood filter, but look what we found!" kind of a thing. But for the brain isn't the default assumption that has it complexity we haven't figure out yet?

Wow!!

“The work coming out is moving this from ‘Are they relevant?’ to ‘This is a major motif of how the cortex processes information,’” said Earl K. Miller(opens a new tab), a cognitive neuroscientist at the Massachusetts Institute of Technology.

Brain waves are to biological neural populations what large-scale, low-dimensional activation modes in the transformer’s residual stream are to an LLM.

This is what Walter J. Freeman III* spent his career working on, surprised he wasn't mentioned. I used to be very obsessed with him.

https://en.wikipedia.org/wiki/Walter_Jackson_Freeman_III

Nonlinear brain dynamics as macroscopic manifestation of underlying many-body field dynamics, https://arxiv.org/html/q-bio/0511037

https://web.archive.org/web/20070609235302/http://sulcus.ber...

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[*] No, not that guy; the son of that guy.

Edit: I've never seen a wikipedia page with so many typos.

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I wonder what the "waves" in LLMs are; The global firing patterns that can help us interpret what the weights are doing en-masse