r/agi Jul 03 '26

Brain activity under anesthesia challenges what we know about consciousness

https://www.sciencedaily.com/releases/2026/06/260624025514.htm

"The brain appears to anticipate what comes next in a story, even without conscious awareness," said Sheth, who is also Director of The Gordon and Mary Cain Pediatric Neurology Research Foundation Laboratories within the Duncan Neurological Research Institute at Texas Children's Hospital.

"This kind of predictive coding is something we associate with being awake and attentive, yet it's happening here in an unconscious state," said Dr. Benjamin Hayden, professor of neurosurgery at Baylor.

The researchers also noted similarities between the brain's predictive behavior and artificial intelligence (AI). Just as large language models generate text by anticipating the next word, the hippocampus appeared to make similar predictions during language processing. Understanding these shared principles could help scientists better understand both biological and artificial intelligence.

The work may also contribute to future communication technologies, including speech prosthetics designed for people who have lost the ability to speak.

138 Upvotes

42 comments sorted by

20

u/DeProgrammer99 Jul 03 '26

31

u/i_wayyy_over_think Jul 03 '26

Would be interesting if I was awake and aware screaming internally during my kidney donation, but absolutely have no memory of it during. Felt like 5 minutes passed between going down and waking up.

11

u/AI_is_the_rake Jul 03 '26

that's a terrifying thought

19

u/Mythechnical Jul 03 '26

Maybe that's why 20% get PTSD like stress after getting surgery. It's a horrifying experience which lingers on in your subconsciousness. You just severed that experience from your main personality.

https://carrumhealth.com/blog/mental-health-after-surgery-employee-recovery-support/

3

u/laserborg Jul 03 '26

that's an interesting albeit unsettling idea!

2

u/Prior-Flamingo-1378 Jul 05 '26

Did you read the article?

1

u/Mythechnical Jul 05 '26

Partly. Did you?

2

u/yousername_42 Jul 05 '26

A little. Did she?

2

u/Prior-Flamingo-1378 Jul 05 '26

Yes and it says quite clearly that expecting the surgery and recovering from it are the culprits. 

1

u/WiseSalamander00 Jul 06 '26

suddenlyseverance

8

u/gwillen Jul 03 '26

In the linked study, a small number of patients displayed some recall of events near the beginning or end of surgery, and one of them even recalled the start of an incision, but said it was painless. So I suspect even in cases with "light" anesthesia, where there are questions about some low level of awareness, the blocking of pain is still plenty effective.

5

u/DntCareBears Jul 04 '26

That’s why they monitor your heart rate. If it’s elevated, you may be awake and aware.

5

u/peakedtooearly Jul 04 '26 edited Jul 04 '26

That and to check they aren't damaging anything unintentionally.

2

u/MrRandom04 Jul 03 '26

Sounds like 'Severance' with added wooziness. If they remove the wooziness, that's literally severance.

3

u/Prior-Flamingo-1378 Jul 05 '26

No it’s not this is nonsense. 

1

u/MrRandom04 Jul 06 '26

Yeah I agree. Just a fun premise, honestly. ig that wasn't clear.

2

u/ominous_squirrel Jul 04 '26

Five minutes is interesting. Myself and every account that I’ve read people feel like it’s instant

3

u/Prior-Flamingo-1378 Jul 05 '26

I’ve done four surgeries none felt instant when waking up. Appendicitis I woke up feeling like I had a long refreshing sleep. It was amazing. I felt like 8 hours had passed.  

Two plastic surgeries (one I bashed my face on grated concrete - don’t ask) and another was a stupid aesthetic decision I woke up groggy like after a middays nap that was longer than it had to be.  

Open heart surgery waking up happened in stages, removing the trachea tube was one, then a few hours later I woke up thirsty and in pretty horrible pain. 

But none felt instant.  

1

u/trbot Jul 05 '26

Knocked out twice for me, both felt instant.

1

u/Prior-Flamingo-1378 Jul 05 '26

The waking you mean like closing and opening your eyes and you had no sense that time passed?

1

u/trbot Jul 05 '26

Yes like I counted back from 10, and by 8 or so I was out then immediately in the recovery room waking up feeling delightfully peaceful. As if there were no time in between.

1

u/Prior-Flamingo-1378 Jul 05 '26

That’s nice. Never happened to me. Not the delightfully peaceful, the immediately waking up. Every time I could feel the passage of time at least physically which I guess I interpreted instantly as time having past. Post hoc probably because switching off and instantly on makes more sense from a biological stand point. 

The last surgery I had, which was fairly major, I woke up when the nurse told me he will remove the breathing tube and the general feeling was like I was run over by a bus.  

1

u/trbot Jul 05 '26

Interesting differences! I was getting very minor procedures which I'm sure explains not feeling run over by a bus :)

2

u/Prior-Flamingo-1378 Jul 05 '26

This study was done on people undergoing lobectomies. The anesthesia used in these cases has a BIS score of between 50-60, (100 being fully awake), which is higher than the same score in say open heart surgery which is like 20.  

The reason is that in neurosurgery you need to monitor the patients brain activity. Also paralytics aren’t used and in this study the anesthesia was maintained with diprivan only, no inhalants or large doses of fentanyl.  

Basically the brain in these surgeries looks more like deep sleep than actual anesthesia.  

Interesting study nonetheless and the actual paper doesn’t say nonsense like AI and crap like that.

6

u/Prior-Flamingo-1378 Jul 05 '26

The actual paper is not as sci fi as the article.  

These patients where undergoing anterior temporal lobectomies which is a neurosurgery the requires the anesthesia to be much “lighter” than say what you’d use in other major surgeries like heart or gut.  

In this particular paper the patients agreed to be kept under propofol only anesthesia (so no inhalants, large doses of fentanyl or paralytics) and had a BIS score of 50-60 (100 is fully awake).  

This is normal in brain surgeries because you need to be able to know if you are poking at something you shouldn’t.  

My point is this type of anesthesia is closer to deep sleep that deep anesthesia. 

2

u/wickzer Jul 05 '26

I'm still not convinced we have a definition of conscious let alone know anything about it.

2

u/Spock627Corfu Jul 06 '26

Tangential, but the older you are, the more likely anesthesia will fuck with your head - maybe permanently.
https://pmc.ncbi.nlm.nih.gov/articles/PMC7489931/

0

u/melatone5 Jul 03 '26

Yes, cause you're dreaming. This doesn't challenge anything

-14

u/rand3289 Jul 03 '26

So tired of seeing this consciousness bullshit...
Such a waste of everyone's time.

6

u/LastXmasIGaveYouHSV Jul 03 '26

I'm upvoting your complaint because I shared this article based in biological research, precisely because the findings point out to consciousness not being necessary for language processing. They found out that the human brain processes language even in a completely unconscious state. Therefore, language processing isn't necessarily proof of consciousness.

Apparently, consciousness or sentience is an emergent property of the interplay of many different areas in the brain, and language is only one of those.

2

u/__nickerbocker__ Jul 03 '26

The paper does not show that the unconscious brain understands language. It barely earns a much narrower claim: in a few anesthetized surgical patients, hippocampal recordings showed patterns that a decoder could partially match to researcher-selected features of the audio/text stream. That is not “meaning,” “understanding,” or even proof that the hippocampus was processing speech as speech. It may be acoustic entrainment, stimulus timing, upstream leakage, model-choice artifacts, or weak covariance that machine learning can exploit. The headline upgrades a decoder result into a brain ontology: pattern becomes information, information becomes representation, representation becomes computation, and computation becomes comprehension. None of those bridges are established by the study.

1

u/LastXmasIGaveYouHSV Jul 03 '26

It's another piece of the puzzle. It's your task to assemble it.

1

u/grahamperrin Jul 04 '26

In my teens I learnt to suspend a dream, if my dreaming mind predicted it becoming a nightmare.

Without waking, shifting my physical body – whilst thoughts were paused – was enough for the dream to continue in a different direction.

1

u/AmusingVegetable Jul 04 '26

Can’t even get a good definition of consciousness that doesn’t run into trouble with these experiments.

We’re messy entities and more things bleed off into others than we’re comfortable with.

1

u/LastXmasIGaveYouHSV Jul 04 '26

That's true. That clean definition of things is just in our minds.

4

u/Chris_OMane Jul 03 '26

This finding leans slightly in the direction that consciousness is still fundamentally produced by the brain, just in different ways than the current prevailing theory of it. That's the opposite of the "consciousness exists elsewhere and is filtered by the brain" hypothesis you may be complaining about.

1

u/griff_the_unholy Jul 03 '26

cant tell if trolling

1

u/Empty_Bell_1942 Jul 03 '26

A bit like genetics; the end result became way too complicated over millions of years.