Boris D Heifets

Anesthesiologist, neuroscientist, amateur psychiatrist. I know where the most powerful psychotropic drugs in the hospital are.

[Boris D Heifets @TheBorisLab]

Applications are open! We have an *incredible* lineup of speakers at the 2027 GRC/GRS on Consciousness, Anesthesia and Evolutionary Biology - January 17-22, 2027 SoCal. Keynotes by Christof Koch, @doristsao (GRC) and @mattlark (GRS). see link below for the prelim program -

[Boris D Heifets @TheBorisLab]

@Josh__Hardman Can I do drums??

[Zeest Khan, MD @doctor_zeest]

I didn't know what my colleagues would say when I met them this weekend. The ASA is a prestigious medical society.

I didn't have research to present. I'm not even working in the operating room anymore.

I have long COVID and I now work with people whose lives (like mine) have been impacted by the unexpected.

I didn't need to worry. EVERYONE wanted to learn about long COVID. Almost everyone had been personally impacted or knew someone who had chronic illness or another health scare.

As anesthesiologists, we are experts at saving bodies, but we don't talk about ways to save our own. Thank you @ASAMonitor and @LudwigLin for highlighting my story. There are more of us in this boat than you might think.

[Boris D Heifets @TheBorisLab]

@HesseJanis @doristsao Absolutely! Amazing work 🤩

[Boris D Heifets @TheBorisLab]

Seeing the excitement this has stirred up... the inimitable @doristsao will be delivering a keynote address at the 2027 GRC on Consciousness, Anesthesia & Evolutionary biology in January! *link below*. Applications closing soon- come see the greats debate!

[Doris Tsao @doristsao]

1/ We discovered something totally unexpected about the neural structure of consciousness that overturns decades of thinking on its biological basis and brings us significantly closer to the recipe for generating conscious awareness.
New preprint: https://t.co/K8BwiHXvXg (led by @HesseJanis, with @FrankLanfranchi, @_conor_mcgrory, @Yuelin_Shi, and @EngelTatiana)

[Boris D Heifets @TheBorisLab]

@stochasticDrew Apply! We are not yet full- poster not required

[British Journal of Anaesthesia @BJAJournals]

An intubating dose of rocuronium gave a blockade lasting 30% longer in the morning (08:00 to 11:00) than in the afternoon (14:00 to 17:00). G. Warman et al. ⏰ #BJAEd #PeriopMed https://t.co/Ev3d8qXava

[Cara Weisman @WeismanCara]

This seems like a profound result that might be the first crack in the hull between us and a meaningful theory of consciousness. I go to these meetings hoping to witness key transitional periods that will be written about in 50 years. Don't miss your chance.

[Cara Weisman @WeismanCara]

@stochasticDrew @TheBorisLab Can't speak for the GRC, but as GRS co-chair, we are currently not close to capacity, and we will prioritize early applications. We encourage posters, though, even if you don't think your work is related. Feel free to DM/email me if you want to discuss further.

[Deepak Sharma @deepak_neuro]

Can we have a show of hands from anesthesiologists who have already made their contribution to @FAERanesthesia #ANES26

[Boris D Heifets @TheBorisLab]

@deepak_neuro @FAERanesthesia @NarouzeMD @emilysharpe @nelkassabany @ruthi_landau @RealMilesBerger @jeffgadsden @Siva6faces @SobanUmar @HarrietHopfMD Done!

[Boris D Heifets @TheBorisLab]

GRC meeting: https://t.co/gxpqNvNH34

GRS meeting: https://t.co/S1HmbvT7MC

https://t.co/AgZVRK40uc

[Boris D Heifets @TheBorisLab]

Is AI conscious? I have no idea. But I'm excited to spend a week talking about problems in consciousness, disorders of consciousness, dreaming, delirium, perception that may actually be experimentally tractable 😅

Apply now - space is limited! Links below

[Boris D Heifets @TheBorisLab]

Is AI conscious? I have no idea. But I'm excited to spend a week talking about problems in consciousness, disorders of consciousness, dreaming, delirium, perception that may actually be experimentally tractable 😅

Apply now - space is limited! Links below

[Doris Tsao @doristsao]

Peer experts: we would be extremely grateful for your timely feedback (e.g., through the bioRxiv comment function). As you can see, the interest is immense, and we will be building on this work at Astera. If you see a critical shortcoming, we want to know asap.

[Doris Tsao @doristsao]

The outpouring of interest in our paper has been … a bit insane.

May I make four points?

1. We have not shown that “consciousness has a frame rate.”

I can see why people draw this conclusion: we report that inferotemporal and prefrontal cortex alternate between conscious and suppressed states roughly every 60 ms during binocular rivalry.

Consciousness depends on many brain areas, and our paper reports results from only a few select nodes.

We still don’t know how conscious access works--the actual recipe for generating conscious experience. What we have shown is that deep in the brain there is an extremely strong signal, rich enough to reconstruct a high-dimensional face in detail, that is inaccessible to consciousness. As I argued in the original tweet, this makes the problem of conscious access a lot more experimentally tractable. But to claim “consciousness has a frame rate,” one would need to have actually solved the mechanism for conscious access and shown that this mechanism operates at a frame rate.

While we currently don’t know conclusively one way or the other (see VanRullen & Koch, 2003 for a review of positive evidence), I personally am skeptical that consciousness has a frame rate. I believe the brain, within posterior parietal cortex, has continuous tracking mechanisms that actively represent the persistence of matter, including ourselves as physical bodies. The coupling between these persistent tracking processes and feature representations across the brain (like those in face patches) is, I think, the essential mechanism of conscious access.

This coupling need not happen at the rate of inferotemporal alternations (and inferotemporal cortex itself may not even alternate outside of the artificial situation of binocular rivalry). As an analogy: imagine the area crucial for conscious access holding a steady drone note, while inferotemporal cortex alternates between two notes, one in harmony and one dissonant. Inferotemporal content might couple to the drone only at moments of harmony, yet experience would still be continuous, because the drone itself (the tracking process that I believe is at the core of conscious perception) never stops. And areas without conflicting content, like auditory cortex during visual rivalry, could stay in continuous harmony with the drone.

In sum, there is no reason to conclude from our study that consciousness is discrete, with a "frame rate."

2. Our results resemble Jezek et al. 2011 (as @jjsakon notes).

Jezek et al. trained rats in two boxes that were identical except for their lighting cues, so that hippocampal place cells formed two distinct maps, one per box. They then “teleported” the rat by abruptly switching the lights. For a few seconds afterwards, CA3 place-cell activity flickered between the two maps, synced to the theta cycle (~125 ms).

@StanDehaene first pointed this paper out to me, and reading it blew me away. To my mind it is the strongest evidence for a bistable attractor in the brain, because the competing maps are stored within the hippocampus itself.

I think the phenomenon we see may be very similar at the circuit level: a bistable attractor network within inferotemporal cortex that alternately converges to one of two patterns, as cells in face patches work together to build a coherent representation of the input. In our case, both images are present in the input, so the competition could arise within IT or be inherited from earlier areas such as V1--recording there is an important next step. (It also still puzzles me that we didn’t see strong coherence between face patches ML and AM.)

More broadly, what’s different about our paper is the brain area (inferotemporal cortex, often modeled as a feedforward DNN) and the ability to relate the two competing patterns to consciousness, with one granted conscious access and the other not.

3. Please comment on bioRxiv!

The Twitter attention has been cool, but I really hope colleagues will be generous enough to post detailed commentary on bioRxiv, where there are currently 0 comments. As @seemaychou points out, peer review doesn’t have to come from just three anonymous reviewers. We would be truly grateful for your critical feedback.

4. Stay tuned

This work was done at Caltech, Berkeley, in collaboration with @EngelTatiana at Princeton, funded by NIH and HHMI.

I hope to share our vision soon for how we can solve consciousness @AsteraInstitute

[Janis Hesse @HesseJanis]

Very excited to share the most important discovery of my career yet: your brain switches between a conscious and an unconscious mode ~15 times every second. Consciousness may depend not on where in the brain activity occurs but when.
Find out more below.
https://t.co/23dyMGnaLX

[Doris Tsao @doristsao]

1/ We discovered something totally unexpected about the neural structure of consciousness that overturns decades of thinking on its biological basis and brings us significantly closer to the recipe for generating conscious awareness.
New preprint: https://t.co/K8BwiHXvXg (led by @HesseJanis, with @FrankLanfranchi, @_conor_mcgrory, @Yuelin_Shi, and @EngelTatiana)

[Stanford Anesthesiology @stanfordanes]

In a recent opinion piece, researchers explore whether new masking approaches and study designs could help improve the interpretability of psychedelic clinical trials while protecting participant trust and safety.

Read on: https://t.co/80k7sjObOA
@TheBorisLab

[D. Parker Kelley @sequencemyneuro]

Are psychedelics anti-inflammatory!?
I am beyond excited to present the first systematic review and meta-analysis of the immunomodulatory effects of serotonergic psychedelics!
https://t.co/CXNQNR7E9k

[D. Parker Kelley @sequencemyneuro]

Congratulations and many thanks to my co-1st author, @anna_skovgaard @geraldbillac @MichaelBenros Ellen Bradley, MD @TheBorisLab @thebandlab @kristen_nishimi, @thethrivelab

[D. Parker Kelley @sequencemyneuro]

Congratulations and many thanks to my co-1st author, @anna_skovgaard , and our incredible team @geraldbillac @kristen_nishimi @MichaelBenros @TheBorisLab @thebandlab !!!!