Evidence map›Paper›PMID 39933965›Full record

ArticleBritish journal of anaesthesia2025

Connectome harmonic decomposition tracks the presence of disconnected consciousness during ketamine-induced unresponsiveness.

Milan Van Maldegem, Jakub Vohryzek, Selen Atasoy, Naji Alnagger, Paolo Cardone, Vincent Bonhomme, Audrey Vanhaudenhuyse, Athena Demertzi, Oceane Jaquet, Mohamed Ali Bahri and 4 more

Abstract read
In one paragraph

Article in British journal of anaesthesia, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed.

  1. Review
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

14 authors.

Milan Van MaldegemDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK; Department of Physiology, Development & Neuroscience, University of Cambridge, Cambridge, UK; Division of Anaesthesia, University of Cambridge, Cambridge, UK. Electronic address: mv554@cam.ac.uk.
Jakub VohryzekCentre for Eudaimonia and Human Flourishing, Department of Psychiatry, University of Oxford, Oxford, UK; Centre for Brain and Cognition, Computational Neuroscience Group, Department of Information and Communication Technologies, Universitat Pompeu Fabra, Barcelona, Spain.
Selen AtasoyCentre for Eudaimonia and Human Flourishing, Department of Psychiatry, University of Oxford, Oxford, UK; Centre for Music in the Brain, Aarhus University, Aarhus, Denmark.
Naji AlnaggerComa Science Group, GIGA-Consciousness, University of Liege, Liege, Belgium; Centre du Cerveau, University Hospital of Liege, Liege, Belgium.
Paolo CardoneComa Science Group, GIGA-Consciousness, University of Liege, Liege, Belgium; Centre du Cerveau, University Hospital of Liege, Liege, Belgium.
Vincent BonhommeAnaesthesia and Perioperative Neuroscience, GIGA-Consciousness, University of Liege, Liege, Belgium; Department of Anesthesia and Intensive Care Medicine, University Hospital of Liege, Liege, Belgium.
Audrey VanhaudenhuyseConscious Care Lab, GIGA-Consciousness, University of Liege, Liege, Belgium; Algology Interdisciplinary Centre, University Hospital of Liege, Liege, Belgium.
Athena DemertziPhysiology of Cognition Lab, GIGA-CRC Human Imaging Unit, University of Liege, Liege, Belgium; Psychology and Neuroscience of Cognition Research Unit, University of Liege, Liege, Belgium.
Oceane JaquetDepartment of Anesthesia and Intensive Care Medicine, University Hospital of Liege, Liege, Belgium.
Mohamed Ali BahriGIGA-CRC Human Imaging Unit, University of Liege, Liege, Belgium.
Pablo NunezComa Science Group, GIGA-Consciousness, University of Liege, Liege, Belgium; Centre du Cerveau, University Hospital of Liege, Liege, Belgium.
Morten L KringelbachCentre for Eudaimonia and Human Flourishing, Department of Psychiatry, University of Oxford, Oxford, UK; Centre for Music in the Brain, Aarhus University, Aarhus, Denmark.
Emmanuel A StamatakisDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK; Division of Anaesthesia, University of Cambridge, Cambridge, UK.
Andrea I LuppiDepartment of Clinical Neurosciences, University of Cambridge, Cambridge, UK; Division of Anaesthesia, University of Cambridge, Cambridge, UK; Centre for Eudaimonia and Human Flourishing, Department of Psychiatry, University of Oxford, Oxford, UK; Division of Information Engineering, University of Cambridge, Cambridge, UK; St John's College, University of Cambridge, Cambridge, UK.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundKetamine, in doses suitable to induce anaesthesia in humans, gives rise to a unique state of unresponsiveness accompanied by vivid experiences and sensations, making it possible to disentangle the correlated but distinct concepts of conscious awareness and behavioural responsiveness. This distinction is often overlooked in the study of consciousness.

methodsThe mathematical framework of connectome harmonic decomposition (CHD) was used to view functional magnetic resonance imaging (fMRI) signals during ketamine-induced unresponsiveness as distributed patterns across spatial scales. The connectome harmonic signature of this particular state was mapped onto signatures of other states of consciousness for comparison.

resultsAn increased prevalence of fine-grained connectome harmonics was found in fMRI signals obtained during ketamine-induced unresponsiveness, indicating higher granularity. After statistical assessment, the ketamine sedation harmonic signature showed alignment with signatures of LSD-induced (fixed effect =0.0113 [0.0099, 0.0127], P<0.001) or ketamine-induced (fixed effect =0.0087 [0.0071, 0.0103], P<0.001) psychedelic states, and misalignment with signatures seen in unconscious individuals owing to propofol sedation (fixed effect =-0.0213 [-0.0245, -0.0181], P<0.001) or brain injury (fixed effect =-0.0205 [-0.0234, -0.0178], P<0.001).

conclusionsThe CHD framework, which only requires resting-state fMRI data and can be applied retrospectively, has the ability to track alterations in conscious awareness in the absence of behavioural responsiveness on a group level. This is possible because of ketamine's unique property of decoupling these two facets, and is important for consciousness and anaesthesia research.

Indexed as

Anesthetics, DissociativeConnectomeConsciousnessKetamineAdultBrainFemaleHumansMagnetic Resonance ImagingMaleUnconsciousnessYoung AdultAnesthetics, DissociativeKetamineconnectome harmonicsconsciousnessdissociative anaesthesiafunctional MRIketamine dreamsunresponsiveness

Identifiers

PMID39933965
PMCPMC11947573

What Socratic holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.