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Wiki: observability and claim ceiling by measurement stack

multimodal is not a synonym for ``seen everything''

Mind Uploading Research Project

Public Page Updated: 2026-04-03 Technical / natural science only (updated with the 2026-04-03 BCSFB / astrocyte / neuroimmune route-family sync)

How to use this page

Read this first to avoid getting lost

This page is a wiki that fixes the ``upper claim limit for each measurement stack,'' which is often overlooked in WBE discussions. It's not enough to say that hidden state is important. Based on primary literature, we will explain what each of EEG/MEG/fMRI, spatial transcriptomics, Patch-seq, volume EM, diffusion-MRI tractography / structural connectome, same-brain functional connectomics, synaptic-density PET, mixed arousal proxy, local transmitter sensor, receptor atlas / PET, glia imaging, and human 1H-MRSI biochemical-similarity / high-resolution 1H-MRSI metabolite-distribution mapping / 31P metabolite-pH-balance / 31P MT exchange-flux / 31P NAD-content mapping / 31P functional NAD-dynamics / deuterium metabolite-mapping-absolute-quantification / deuterium kinetic-rate / ionic / thermal / myelin / BBB / blood-CSF-barrier / choroid-plexus / astrocyte target-route-role split / neuroimmune target-route-role split / clearance routes directly observes and what remains latent.

  • The general idea that ``there is a hidden state'' is reduced to ``which measurement stack and what has not yet been observed?''
  • Fixed a ceiling to prevent the words multimodal / atlas / connectome from being misread as state-complete.
  • EEG / MEG rows now separate conditional deep detectability from general unique recovery, so intracranial-validation studies are not overread as state-complete readout.
  • EEG / MEG rows now also separate the upstream field-formation wall from downstream inverse uncertainty, so channel count or a cleaner map is not misread as newly created observability.
  • Wearable OPM-MEG stays inside the EEG / MEG ceiling unless shielding class, field control, calibration / coregistration, anatomy route, crosstalk, and task regime are disclosed explicitly.
  • Hemodynamic stacks are now split into uncalibrated amplitude, transfer-audited amplitude, and model-conditioned oxygen-metabolism routes, so passing one route is not overread as solving the others.
  • Same-session multimodal acquisition is not treated as self-validating fusion; the site now requires a Fusion Card before the ceiling is raised above the strongest unimodal route.
  • Same-brain functional connectomics is now split into sequential bridge, label-transfer, synaptic-state, and dynamics-identifiability walls, so ``same-brain'' is not overread as one solved route.
  • Destructive ultrastructure routes are now read through preservation, registration, and proofreading burden rather than through resolution language alone.
  • Human diffusion-MRI tractography / structural-connectome rows are now read as acquisition-, endpoint-, graph-, and calibration-conditioned macro pathway priors rather than one stable graph.
  • Destination is divided into structural atlas, cell-type prior, local conditional prediction, and slow-state calibration.
  • SV2A / synaptic-density PET is not one audit item; tracer / quantification route, atlas construction, disease contrast, task / cognition association, and intervention design now stay separated.
  • Astrocyte PET is not one audit item either; SMBT-1 target validation, AD-context contrast, brain quantification, whole-body biodistribution, SL25.1188, and I2BS routes stay separated.
  • Human evidence is also separated into proxy classes, so local ultrastructure, synaptic-density PET, 1H-MRSI biochemical similarity, high-resolution 1H-MRSI metabolite-distribution mapping, 31P metabolite / pH balance, 31P MT exchange-flux, deuterium metabolite-mapping / absolute-quantification routes, deuterium kinetic-rate imaging, ionic / thermal / myelin, BBB, blood-CSF-barrier / choroid-plexus, astrocyte target / route-role split, neuroimmune target / route-role split, and clearance routes are not compressed into one near-direct readout.
  • Human intrinsic-excitability evidence is not one audit item either; local clinical single-unit allocation, sleep-homeostasis / plasticity recalibration, and state-gated perturbation routes stay separated.
  • Human maintenance-state routes are now read on three axes: proxy class, operational maturity, and calibrator role.
  • Regional synaptic-density PET and same-brain functional connectomics are not promoted to presynaptic release-machinery readouts; release-site number and active-zone nanostructure stay separate audit items.
  • Same-subject or same-brain wording is not treated as same-state when the bridge is sequential across live / ex vivo or separated physiological regimes.
Best for
People who want to sort out what modalities are directly visible and which claims are valid using only technology and natural science.
Reading time
14-20 minutes
Accuracy note
The ``claim ceiling'' column below is not the conclusion declared by each paper. This is an operational inference drawn by this site from variables directly observed in primary literature and state variables that are still unobserved.

Relatively clear at this stage

What we know now

  • EEG/MEG/fMRI provides macroscopic proxies, but not directly for cell types, synaptic efficiency, neuromodulatory fields, and glial status.
  • Even wearable OPM-MEG remains a route-conditioned macro field observable rather than a portability-based escape from the EEG / MEG claim ceiling.
  • In hemodynamic modalities, uncalibrated BOLD / HbO / HbR amplitude, transfer-audited amplitude, and model-conditioned oxygen-metabolism routes are different inferential objects, and vascular transfer state such as baseline perfusion, CVR, and superficial/systemic contamination can still dominate the simpler rows.
  • Whole-brain spatial transcriptomics provides a major advance in cell-type taxonomy and spatial location, but the sufficiency of dynamic states is another matter.
  • Patch-seq and same-brain connectomics reduce degeneracy, but the sufficiency of whole-brain coverage and long-term maintenance-state remains.
  • Same-brain functional connectomics can strengthen local structure-function links while still relying on morphology-bridged labels and leaving current synaptic state, presynaptic release machinery / active-zone nanostructure, and unique dynamics unresolved.
  • A diffusion-MRI-derived human connectome is not one stable object; hub maps, laterality, and bundle recovery remain conditioned by acquisition scheme, endpoint assignment, graph construction, and uncertainty handling.
  • Local transmitter / glia imaging is effective for calibrating coarse proxies, but it does not directly provide whole-brain ground truth.
  • Human 1H-MRSI biochemical similarity, high-resolution 1H-MRSI metabolite-distribution mapping, 31P metabolite / pH balance, 31P MT exchange-flux, deuterium metabolite-mapping / absolute-quantification routes, deuterium kinetic-rate imaging, ionic, thermal, myelin, BBB, blood-CSF-barrier / choroid-plexus, astrocyte target / route-role split, neuroimmune target / route-role split, and clearance routes reduce different latent-state error terms and should not be summarized as one direct path to maintenance-state completeness.
  • Human local clinical-unit allocation and noninvasive perturbation-conditioned routes also reduce different latent-state error terms, so `human excitability evidence` is not one reusable row.
  • A real human proxy route may still calibrate only one bounded hidden-state family, so proxy class and operational maturity do not by themselves fix calibrator role.
  • Same-subject or same-brain wording can solve specimen identity while still leaving state continuity unresolved across time gaps, regime changes, and tissue transformation.

Still unresolved beyond this point

What we still do not know

  • It cannot yet be determined which stack combination will most efficiently reduce degeneracy for WBE.
  • The sufficient conditions for which latent state should be obtained in the same brain, whole brain, and long-term longitudinal study are not yet determined.
  • How to optimize the augmentation order between stacks can also vary depending on the task, species, and time constant.

Learn the basics

Check the basics in the wiki

What the wiki is for

The wiki is a learning aid. For the project's official current synthesis, success criteria, and operating rules, always return to the public pages.

The shortest conclusion

The weakness of the current site is that even though it was possible to enumerate important hidden states, it did not highlight which measurement stack directly observes what and where it hits the claim limit. Based on the primary literature, EEG/MEG/fMRI strengthens macro state tracking, whole-brain spatial atlas strengthens cell-type and spatial arrangement, Patch-seq bridges cell-type and morpho-electric phenotype, volume EM strengthens structural scaffolding, diffusion-MRI tractography strengthens living-human macro pathway priors, same-brain functional connectomics strengthens local conditional prediction, and local transmitter/astrocyte imaging strengthens coarse proxy calibration. However,no stack alone provides state-complete reconstruction. Therefore, on this site, we clearly specify the claim ceiling for each measurement stack, and prohibit expressions that exceed that.

Scope of this page

Philosophy, legal systems, and individuality are not covered here. What we are dealing with is the question of ``what can be seen directly through observation, and what is still latent'' from the perspective of technology and natural science only.

Weaknesses to be explored in depth

Conventional public pages already knew that connectome alone was not enough, maintenance-state remained, and comparisons should be made using augmentation/ablation. However, this alone leaves room for readers to overinterpret when they see the words multimodal, atlas, connectome, and same-brain, saying, ``I see pretty much everything.'' The weakness is that the discussion ofstate variables andmeasurement stacks have not yet been fully integrated.

Therefore, on this page, we will integrate the direct observables of each stack, what can be said a little more strongly, what will still remain in latent state, and the claim ceiling allowed by this site into one table.

Observability and claim ceiling per measurement stack

How to read

The last column of the table below is not a summary of each paper, but the operating rules for this site. In other words, it is a well-founded upper bound subtracted from the stack's directly observed variables and still unobserved state variables.

measurement stack What is directly observed Something that can be said relatively strongly What remains latent Claim ceiling on this site
EEG / MEG Globally synchronized current field and its time change, with movement-tolerant MEG only under declared shielding / field-control conditions. ms-scale global state transitions, frequency band dynamics, closed-loop timing constraints, and route-conditioned movement-tolerant macro electrophysiology can be audited. The uniqueness of the deep source, cell type, current synaptic efficiency, neuromodulatory field, and glial/metabolic state are not directly determined. Macro state tracking and weak L2. It does not raise to cell/synapse granularity or state-complete claims.
BOLD / HbO / HbR amplitude (uncalibrated hemodynamic route) BOLD / HbO / HbR amplitude and slow regional cofluctuation. Wide coverage, recruitment patterns, and coarse within-subject state occupancy can be tracked as hemodynamic-limited differences. ms timing, excitation/inhibition separation, local transmitter dynamics, current synaptic efficacy, and separation of neural change from vascular transfer state / superficial or autonomic contamination remain unresolved. Up to wide-area hemodynamic-limited difference. Without transfer-side calibration, this row is not promoted to a clean neural difference.
Vascular-calibrated hemodynamic route (CVR / baseline-perfusion / short-separation audit) BOLD / HbO / HbR amplitude plus named vascular-state covariates, short-channel signals, or baseline-perfusion calibration used to audit transfer-side variation. Protocol-scoped group or longitudinal comparisons can be strengthened after declared transfer-side calibration, and superficial / systemic confounds can be reduced rather than ignored. Neural quantity type, oxygen metabolism, cell-specific activity, and maintenance-side neurovascular / BBB controller state remain unresolved. Up to transfer-audited hemodynamic comparison. Passing this row does not by itself create a neural-quantity or neurovascular-support readout.
Model-conditioned oxygen-metabolism route (qBOLD / OEF / CMRO2 family) Multi-contrast hemodynamic observables combined with an explicit physiology model to estimate OEF / CMRO2 or related macro metabolic quantities. A named oxygen-metabolism quantity can be compared to plain BOLD / HbO / HbR and can reveal agreement or sign dissociation under the declared model. Model-free neural drive, cell-type-specific energy use, transmitter-specific coupling, and direct controller identity remain unresolved; quantity estimates still depend on calibration and model assumptions. Up to a model-conditioned macro oxygen-metabolism route. It is not promoted to direct neural-state ground truth or to a generic hemodynamic truth meter.
whole-brain spatial transcriptomics / cell atlas Ex vivo transcriptomic cell type and spatial arrangement. Like Yao et al.'s whole-mouse-brain atlas, it can greatly advance cell-type taxonomy, regional distribution, and molecular maps. The current firing rules, synaptic efficiency, neuromodulatory/glial state, sleep-history, and destination after perturbation remain. Up to molecular atlas / cell-type prior. It does not increase dynamic completeness or current state sufficiency.
Patch-seq / morpho-electric-transcriptomic bridge Compatible with single cell transcriptome, morphology, and electrophysiology. Like the systems of Gouwens et al. and Gamlin et al., it is possible to strengthen the bridge between cell-type labels, morpho-electric phenotypes, and some connectivity motifs. Whole-brain coverage, same-brain circuit context, current network state, and longitudinal plastic history remain. Up to cell-type-specific prior and local parameter constraints. It is not used for whole-brain state completeness.
volume EM connectomics This is a structural snapshot of hyperfine morphology and chemical synapse. You can strengthen the structural scaffold, projectome, and candidate circuits like Dorkenwald et al.'s whole-brain fly wiring diagram. Current synaptic weight, intrinsic excitability, neuromodulatory context, glial slow state, and sleep-dependent maintenance are not directly included. Structural atlas / scaffold. Do not replace connectome-complete with emulation-complete.
same-brain functional connectomics Co-registered in vivo activity measurements and a later reconstructed local EM connectome in a named same-brain pipeline. Like MICrONS and linked analyses, sampled local circuits can strengthen structure-function correspondences, local connection rules, and connectome-constrained conditional prediction within the measured region / task / state. Same-time whole-brain state, current synaptic efficacy / release state / active-zone architecture, direct transcriptomic identity unless separately measured, unique dynamical parameterization, and long-horizon maintenance-state remain unresolved. Up to a sequential local structure-function scaffold and local conditional prediction. We do not promote it to current synaptic-state or presynaptic release-machinery readout, direct cell-type truth, unique dynamics, or a whole-brain twin.
diffusion MRI tractography / structural connectome Diffusion-weighted signal plus model-derived local orientation estimates; bundle, endpoint, and parcel-graph claims appear only after tracking, endpoint assignment, and graph construction. Macro white-matter pathway priors, named bundle hypotheses, and protocol-scoped parcel-connectivity comparisons can be strengthened when acquisition, endpoint policy, and graph-construction route are disclosed. Synapse identity, direction, current weight, cortical endpoint completeness, stable hub / laterality metrics independent of filtering or parcellation, and protocol-invariant graph meaning remain unresolved; uncertainty and ex vivo calibration still sit downstream. Up to an acquisition-, endpoint-, graph-, and calibration-conditioned macro pathway prior. We do not read it as an edge-complete human connectome or one stable graph by default.
SV2A PET / synaptic-density PET Tracer-defined regional SV2A binding interpreted through kinetic modeling or a validated simplified scan window. You can strengthen human in vivo regional synaptic-density gradients, atlas construction, and disease-linked density comparisons. Current release probability, release-site number, active-zone nanostructure / priming-site assembly, postsynaptic receptor occupancy, task-evoked momentary synaptic efficacy, and branch-local plasticity state remain unresolved, and anatomy/partial-volume handling can still matter for interpretation. Up to regional synaptic-density proxy. We do not read it as current synaptic efficacy, presynaptic release machinery, or momentary synaptic state.
mixed arousal proxy (pupil / HRV / locomotion / facial motion) Behavior-linked arousal markers and their covariance with ongoing state. You can stratify coarse arousal-like state and test whether a behavioral proxy carries useful variance for the task. Transmitter identity, receptor family, regional release, cell-specific effect, and the whole-brain transmitter field remain unresolved. Up to coarse covariate / stratification. We do not treat it as transmitter-specific ground truth.
local axon activity / transmitter sensor Local cholinergic / aminergic axon activity or local extracellular transmitter signal in the measured region. You can calibrate local chemical dynamics, spatial heterogeneity, and where a mixed behavioral proxy fails or succeeds. The whole-brain distribution, receptor occupancy / downstream effect, and cross-species generalization to human current state remain unresolved. Up to local transmitter-linked calibration. It is stronger than mixed proxy, but it is still not whole-brain neuromodulatory ground truth.
receptor / transporter atlas or autoradiography Group-average regional distribution of selected receptors / transporters and laminar density priors from PET and autoradiography. You can show where selected transmitter systems are likely to differ and which cortical axes they follow. Current occupancy, task-evoked release, individual time-varying state, and cell-specific downstream effect remain unresolved. Up to regional chemoarchitectural prior. It is not read as the current neuromodulatory state.
occupancy PET Ligand- or drug-specific target engagement within a named receptor family over bounded scan windows, interpreted through an explicit tracer and quantification model. You can quantify selected exogenous target engagement for the chosen receptor family, ligand / drug, dose, and scan window. Endogenous transmitter release, unsampled receptor families, laminar / cell-specific effect, and continuous state outside the dosing window remain unresolved. Up to ligand- and dose-limited target-engagement proxy. We do not read it as endogenous release or whole-brain current transmitter state.
displacement / release-sensitive PET Challenge-linked change in binding potential for selected tracers / receptor families over bounded scan windows, used as a proxy for endogenous transmitter release under an explicit task or pharmacological challenge. You can test whether a named challenge perturbs a selected transmitter system within the scanned window and spatial scope. The complete transmitter field, unsampled receptor families, laminar / cell-specific effect, downstream consequence, and continuous state outside the challenge window remain unresolved. Up to receptor-, tracer-, and challenge-limited release proxy. We do not promote it to receptor-family-complete or whole-brain internal-state ground truth.
astrocyte / glial imaging Astrocyte network response and slow-state dynamics to local neurotransmitter input. Like Cahill et al., we can visualize minute-long glial network states and further strengthen slow-state/recovery modeling. Full integration of whole-brain coverage, cell-type-specific generalization, fast synaptic state, sleep-history, and other stacks remains. As far as banning slow-state calibration and glia omission. This alone does not claim whole-brain completeness.

Why ceiling is so different

1. atlas strengthens identity but does not directly provide current state

Yao et al. combined scRNA-seq and MERFISH on whole mouse brain and presented a high-resolution atlas consisting of 34 classes, 338 subclasses, 1,201 supertypes, and 5,322 clusters. This is a major step forward in terms of cell-type taxonomy and spatial location. However, what we can say directly from this is which molecular class the cell belongs to and where it is located, but does not includethe current moment's threshold, gain, synaptic efficacy, sleep-dependent renormalization, or transmitter occupancy. So while atlas is very important, it is safe to read it first as identity prior.

2. Patch-seq is a bridge but does not erase the coverage wall

Gouwens et al. showed that morpho-electric variation remains continuously within the transcriptomic family, and Gamlin et al. mapped MET-types defined by Patch-seq to large-scale EM and showed differences in myelination and synaptic output for each Sst MET-type. This means that cell-type label alone is not enough; adding electrophysiology and morphology is of great value. On the other hand, Patch-seq is sparse and destructive sampling and does not provide the whole brain current state or longitudinal history of the same individual. Therefore, it is abridge and notwhole-brain completeness.

3. EM connectome is a scaffold but does not freeze dynamic state

Dorkenwald et al.'s adult fly whole-brain connectome is a huge step forward, reorganizing approximately 5 × 107 chemical synapses and 139,255 neurons. However, EM is strong because it is a structural scaffold, and it is not a method that directly measures current weight, release probability, neuromodulatory context, and glial/metabolic background. The criticism that follows from this is simple: we must not equate knowing the wiring with knowing the generative state of the moment.

4. Adding same-brain function reduces degeneration, but does not by itself fix labels, current synaptic state, or unique dynamics

MICrONS combines dense calcium imaging, behavioral states, and a later EM connectome in the same brain, and the linked analyses show that same-brain local circuits can support stronger structure-function correspondences and connectome-constrained conditional prediction. This is a real advance over connectome-only. However, the measurable object is still a sequential, local, and regime-bounded bridge, not a same-time whole-brain state sample. It is therefore too weak to treat the label same-brain functional connectomics as one solved class. The remaining walls are not only whole-brain coverage and maintenance-state, but also whether transcriptomic labels were directly measured or morphology-bridged, whether the result constrains current synaptic efficacy / release state / active-zone architecture, and whether the resulting dynamical explanation is unique rather than one member of a still-degenerate family. Therefore, the ceiling of this stack on this site is a sequential local structure-function scaffold or local conditional-prediction route, not current synaptic-state, presynaptic release-machinery readout, or a whole-brain twin.

4.5. Same-brain functional connectomics is a sequential local scaffold, not current synaptic-state or a unique whole-brain twin

Another weakness that remained on this page was that same-brain functional connectomics could still be overread as if one frontier stack had already solved specimen identity, direct cell typing, current synaptic state, presynaptic release machinery, and dynamical identifiability in one move. That is too weak. Bosch et al. (2022) showed a strong correlative workflow from in vivo physiology to synchrotron microtomography and volume EM, but through a multistage landmark-based route. MICrONS Consortium et al. (2025) then showed a same-brain local pipeline that can support rich structure-function analysis, and Ding et al. (2025) showed that same-brain functional connectomics can reveal a generalized local wiring rule. But Gamlin et al. (2025) still mapped predicted transcriptomic types through morphology-based classification rather than direct transcriptomic readout inside the EM volume. And the remaining latent state is not trivial: Holler et al. (2021), Molnár et al. (2016), Sakamoto et al. (2018), Dürst et al. (2022), Emperador-Melero et al. (2024), and Mittermaier et al. (2024) show that current synaptic efficacy, release probability, active-zone architecture, and membrane-state-gated consolidation are not exhausted by structure-function correspondence, while Beiran & Litwin-Kumar (2025) show that connectome-constrained recurrent networks can still remain dynamically degenerate until extra recordings collapse the solution space. What follows directly is that same-brain functional connectomics is a strong local scaffold, but not a solved route to current synaptic-state, presynaptic release-machinery truth, direct transcriptomic truth, or unique whole-brain dynamics.

Wall What the primary literature now supports Site rule
Sequential bridge wall Same-brain correlative pipelines can carry landmarks, targeted subvolumes, and local structure-function correspondence across stages, but they are still sequential rather than same-time whole-brain state capture. Do not read same-brain as same-time complete state; disclose acquisition order, regime continuity, and local scope first.
Label-transfer wall Same-brain connectomics can support morphology-linked transfer to transcriptomic classes, but that is different from direct transcriptomic measurement inside the reconstructed volume. Do not read predicted transcriptomic type as direct cell-type truth unless the assay route is named explicitly.
Synaptic-state wall Structure-function correspondence, synapse size, and identified connectivity strengthen priors on function, but current efficacy, release probability, active-zone architecture, and membrane-state-gated consolidation still depend on additional state variables. Do not read same-brain functional connectomics as current synaptic-state or presynaptic release-machinery readout without a direct synaptic-state assay.
Dynamics-identifiability wall Even when connectivity is fixed, recurrent networks with different biophysical parameters can generate compatible activity until additional recordings constrain the solution space. Do not read connectome-constrained prediction as unique recovered dynamics unless the extra-recording / perturbation route that removes degeneracy is disclosed.
Operating rule for same-brain functional connectomics

On this site, same-brain functional connectomics is read first as a sequential local structure-function scaffold or local conditional-prediction route. To argue above that ceiling, a submission now has to disclose the bridge class, whether labels were directly measured or transferred, whether any route directly probed current synaptic state or presynaptic release machinery, and what extra recordings or perturbations were required to narrow the dynamical solution space.

4.6. Destructive ultrastructure still faces a preservation / registration / throughput wall

Another weakness that remained on this page was that volume EM, petascale, or same-brain could still be overread as if destructive ultrastructure had already solved native-state preservation, whole-brain scaling, and reconstruction quality in one move. That is too weak. Lu et al. (2023) showed that conventional aldehyde fixation collapses extracellular space, that the fixation time course itself is not instantaneous, and that high-pressure freezing preserves extracellular space only in samples thinner than roughly 200 μm. Shapson-Coe et al. (2024) then showed that a rapidly preserved human sample can yield a remarkable nanoscale reconstruction, but still as a 1.05 mm3 surgical fragment with 1.8 PB raw data and 326 days of imaging. MICrONS Consortium et al. (2025) showed that same-brain function plus EM is a sequential local pipeline rather than simultaneous state capture, and Dorkenwald et al. (2024) showed that even the adult fly whole-brain frontier still depended on proofreading, thresholding, and substantial manual correction effort. What follows directly is that resolution alone does not erase preservation artifacts, local registration limits, or reconstruction burden.

Wall What the primary literature now supports Site rule
Preservation wall Fixation route changes what the ultrastructure looks like; preserving extracellular space and fine geometry requires an explicit preservation protocol and does not mean that live molecular or electrophysiological state was captured. Do not read nanoscale or EM as automatic native-state preservation.
Registration wall Same-brain function + EM is stronger than connectome-only, but it is still a sequential, local, and registration-limited route rather than same-time whole-brain state capture. Do not read same-brain as same-time complete state.
Throughput / proof wall Petascale imaging still implies long acquisition windows, sectioning/alignment risk, segmentation trade-offs, and nontrivial proofreading burden. Do not read petascale as finished, error-free, or whole-brain-ready.
Operating rule for destructive ultrastructure

On this site, a destructive ultrastructure result is read first as a structural scaffold or local ex vivo scaffold unless it also discloses preservation route, live-to-fix window, registration scope, section-loss / alignment risk, segmentation / proofreading status, and omitted live-state families. That disclosure bundle is formalized in Verification: Destructive-Structure Route Card.

4.7. Human diffusion MRI tractography is a route-conditioned macro pathway prior, not one stable graph

Another weakness that remained on this page was that connectome, dMRI, or tractography graph could still be overread as if a living-human structural stack already produced one stable object. That is too weak. Reveley et al. (2015) showed that superficial white matter can impede detection of long-range cortical connections, and Schilling et al. (2018) showed that tractography endpoints remain biased toward gyral crowns across algorithms and diffusion models. The newer literature then shows that even after tracking, the graph itself still moves. Gajwani et al. (2023) showed across 40 pipelines and 44 group-representative reconstructions that hub location is highly variable, and He et al. (2024) showed that tractogram filtering can significantly change connectome laterality. Upstream of that, McMaster et al. (2025) showed that voxel-size variance changes the resulting connectome and recommended harmonized resampling, while Bramati et al. (2026) showed on the same 3 T scanner with uniform processing that common diffusion-sampling schemes can still shift voxel-wise metrics and tractography outputs. Downstream, Manzano-Patrón et al. (2025) showed that fibre-orientation uncertainty can be propagated into tractography rather than hidden, and Zhu et al. (2025) showed that MRI plus microscopy can improve reconstruction in a hybrid calibration setting. What follows directly is that a diffusion-MRI-derived human connectome is not one stable graph by default; it is an acquisition-, endpoint-, graph-construction-, and calibration-conditioned estimate.

Wall What the primary literature now supports Site rule
Endpoint / surface-assignment wall Long-range cortical endpoints can still be hidden by superficial white matter or over-assigned toward gyral crowns, so cortical edge coverage is not a direct observable of the diffusion signal. Do not read a tractography endpoint map as cortical edge completeness without naming the surface-assignment route and remaining endpoint-limited territory.
Graph-construction wall Hub topology, laterality, and other parcel-graph metrics can move across plausible filtering, weighting, thresholding, or group-reconstruction choices. Do not read a tractography graph metric as anatomy by default; disclose the graph-construction route and whether the result survives plausible pipeline variation.
Acquisition / harmonization wall Voxel resolution and q-space sampling scheme can systematically move connectome estimates even before endpoint policy and graph construction are interpreted. Do not compare headline tractography results across scanners, voxel sizes, or sampling schemes without an explicit harmonization route and a statement of whether the result is protocol-scoped.
Uncertainty / calibration wall Posterior uncertainty can be mapped rather than hidden, and ex vivo MRI-microscopy fusion can improve reconstruction, but neither step turns living-human tractography into a finished connectome. Do not treat uncertainty-aware tractography or hybrid calibration as edge-complete human connectome recovery; they are narrower improvements on named error terms.
Operating rule for diffusion-MRI tractography

On this site, a living-human tractography result is read first as a macro pathway prior or bundle-level hypothesis route unless it also discloses acquisition / harmonization, cortical endpoint assignment, parcel-graph construction, stability under plausible pipelines, and how uncertainty or external calibration was handled. That disclosure bundle is aligned here with the deeper tractography route card.

4.8. EEG / MEG still face a visibility / inverse / validation wall

Another weakness that remained on this page was that source-localized, deep-source detectable, or intracranially validated could still be overread as if non-invasive field recordings had already crossed from macro observables into general internal-state recovery. That is too weak. Before any inverse solver runs, there is already a field-formation wall. Ahlfors et al. (2010) quantified source-orientation sensitivity with realistic tissue boundaries and found that the median ratio between the least and most sensitive orientations was 0.63 for EEG but only 0.06 for MEG. Ahlfors et al. (2010) then showed that extended and distributed sources can cancel substantially at the surface. Goldenholz et al. (2009) showed that source extent and anatomy strongly change detectability, with mesial temporal source patches of about 3 cm2 versus 8 cm2 differing by roughly 10 dB in SNR. Piastra et al. (2021) further showed that ignoring the CSF compartment overestimates EEG SNR and that cortical / subcortical sensitivity depends jointly on depth and orientation. Only after that upstream filter do benchmark papers become readable. Mikulan et al. (2020) created the first open human ground-truth benchmark by combining 256-channel HD-EEG with precisely known intracerebral stimulation sites, but they also stated explicitly that stimulation artifacts are non-physiological and that spatial sampling remains anatomically clustered. Unnwongse et al. (2023) then evaluated 3,619 known stimulation locations in 11 patients with simultaneous SEEG and scalp EEG and found mean localization errors ranging from 10.3 to 26 mm, worsening with source depth and lower skull conductivity. Zauli et al. (2024) showed that hidden interictal discharges not visible on single-trial scalp HD-EEG can be uncovered with simultaneous SEEG-triggered averaging, but the resulting ESI still remained method- and parameter-dependent with localization accuracy of only about 2 cm. Hao et al. (2025) reported that simultaneous HD-EEG/SEEG ictal ESI localizes better than interictal ESI, yet still at 14.07 ± 4.62 mm versus 17.38 ± 4.16 mm, with accuracy strongly influenced by source depth and spike power. Finally, Pizzo et al. (2019) showed that MEG can detect direct hippocampal or amygdalar contributions under simultaneous intracranial validation, but only after blind source separation because the deep contribution reaching the surface was small but significant rather than dominating the sensor signal. What follows directly is that EEG / MEG can gain conditional access to some deeper generators, but they still do not collapse field formation, the inverse problem, or general deep-state observability.

Wall What the primary literature now supports Site rule
Field-formation wall Whether a source reaches the scalp with usable SNR already depends on its orientation, depth, cortical folding, source extent, cancellation profile, and the tissue compartments included in the head model. Do not read high-density, deep detectable, or not seen at the scalp without naming the target source class, expected extent, cancellation risk, and CSF / conductivity assumptions.
Visibility wall Deep or low-power events can be absent at the scalp in single trials and may only appear after intracranial timing information, averaging, or special source-separation steps. Do not read scalp-invisible as nonexistent, but do not read recoverable under SEEG guidance as routinely visible non-invasively either.
Inverse / model wall Localization error changes with source depth, skull conductivity, forward model, and chosen inverse method; better fit does not imply unique recovery of the underlying neural state. Do not read source-localized as unique internal-state reconstruction; always disclose the head model, conductivity assumptions, and abstention conditions.
Validation wall Current direct-validation routes mostly come from intracranial stimulation, epilepsy discharges, or simultaneous SEEG/MEG recordings, which answer conditional localization questions rather than physiological whole-brain cognition in healthy humans. Do not promote intracranially validated epilepsy benchmarks to general-purpose whole-brain state readout.
2026-04-01 addendum: wearable OPM-MEG is still inside the EEG / MEG ceiling

This page still left one EEG / MEG shortcut undernamed. The current primary literature does not support treating wearable OPM-MEG as a separate escape hatch from the EEG / MEG claim ceiling. Boto et al. (2018) and Seymour et al. (2021) show motion-tolerant proof-of-concept, but Rea et al. (2021) and Mellor et al. (2022) show that precision field modeling and nulling are part of the route, Holmes et al. (2025) show that lightly shielded operation still relies on active compensation plus tSSS, Rhodes et al. (2025) show that pseudo-MRI remains an MRI-light substitute rather than a new anatomy-free gold standard, Wu et al. (2025) show that crosstalk remains an array-level burden, and Spedden et al. (2025) show whole-body stepping feasibility in three healthy participants rather than broad everyday coverage. Therefore, on this site wearable OPM-MEG is typed as movement-tolerant macro electrophysiology under disclosed shielding, field control, sensor calibration / coregistration, anatomy route, crosstalk, and task regime, not as shield-free, calibration-free, or state-complete observation.

Operating rule for EEG / MEG

On this site, EEG / MEG are read first as macro field observables. Even when deeper sources become conditionally detectable, the claim ceiling stays bounded by field formation, synchrony, source depth, head-model assumptions, and the exact validation route. To argue above macro state tracking or weak L2, a result now has to disclose whether the support comes from field-formation / sensitivity analysis, stimulation benchmark, simultaneous intracranial recording, task-only inference, or model transfer, plus what deep or cell-scale state variables remain latent. For wearable OPM-MEG, the minimum disclosure bundle now also includes shielding class, field nulling / interference suppression, sensor calibration / coregistration, anatomy route, crosstalk burden, and task regime.

5. Hemodynamic stacks also observe through a vascular transfer state

The weak point that needed another pass was not only that BOLD amplitude could be overread as a neural difference, but that improved hemodynamic papers could still be collapsed into one stronger modality row. That was too weak. Murphy et al. (2011), Williams et al. (2023), and Wu et al. (2023) constrain the transfer-side calibration problem: baseline perfusion and CVR move the amplitude. Özbay et al. (2019) and Bolt et al. (2025) constrain a distinct autonomic / body-coupling route in which large-scale fMRI fluctuations co-vary with physiology rather than transparently reporting neural drive. Epp et al. (2025) then showed that about 40% of task-responsive voxels can display oxygen-metabolism changes opposite in sign to the BOLD response, while Jaroszynski et al. (2025) showed that an oxygen-metabolism route itself already depends on an explicit constrained qBOLD + pCASL model stack. What follows directly is that hemodynamic work must now be split into at least three route families on this site: uncalibrated amplitude, transfer-audited amplitude, and model-conditioned oxygen-metabolism estimation.

fNIRS belongs to the same caution family

The same logic applies to cortical hemodynamic modalities beyond fMRI. Yucel et al. (2015) showed that short-separation regression improves both significance and localization for fNIRS tasks with differing autonomic responses, and An et al. (2025) showed that short-channel regression still improves validity and sensitivity even in a working-memory paradigm with minimal motor requirements. Therefore, on this site, fNIRS without short-separation / superficial diagnostic is not treated as a direct neural-difference readout, and short-channel-corrected fNIRS is still read as a transfer-audited hemodynamic route rather than a neural meter.

CVR audit is not the same as a quantity bridge

On this site, passing a vascular-state / CVR audit and estimating an oxygen-metabolism quantity are different achievements. The first can reduce transfer-side ambiguity in BOLD / HbO / HbR amplitude. The second still needs a named physiology model, calibration route, and quantity definition such as OEF or CMRO2. Therefore, a CVR-corrected amplitude result is not promoted here to an oxygen-metabolism result, and a quantitative OEF / CMRO2 paper is still read as a model-conditioned macro metabolic route rather than a direct neural-state meter.

Hemodynamic route family What it tightens What still stays separate Site rule
Uncalibrated BOLD / HbO / HbR amplitude Wide-area recruitment, slow state occupancy, and protocol-scoped hemodynamic differences. Baseline perfusion, CVR, superficial/systemic contamination, autonomic-body coupling, and oxygen-metabolism relation. Read as a hemodynamic-limited difference, not a clean neural difference.
Transfer-audited amplitude
CVR / baseline-perfusion / short-separation route
Whether the observed amplitude difference survives named transfer-side calibration. Neural quantity type, oxygen metabolism, and maintenance-side neurovascular / BBB controller state. Read as a transfer-audited hemodynamic comparison, not as neural or support-state ground truth.
Autonomic / body-coupled global mode Whether part of the hemodynamic variance is better read as shared physiology-linked fluctuation than as task-specific neural signal. Regional neural drive and transmitter-specific interpretation. Do not fold a physiology-linked global mode back into a generic neural gain without an explicit grounding rule.
Model-conditioned oxygen-metabolism route
qBOLD / OEF / CMRO2 family
A named macro metabolic quantity under a declared model, which can agree with or diverge from BOLD amplitude. Model-free neural state, cell-specific energetic allocation, and direct controller identity. Read as a model-conditioned macro metabolic route, not as the default truth layer for all hemodynamic papers.

6. Neuromodulatory routes form a ladder, not one stack

The weakness that needed another pass was that this page still let pupil / HRV, local transmitter imaging, receptor maps, occupancy PET, and displacement / release-sensitive PET sound closer than they are. That was too weak. Reimer et al. (2016) showed that pupil fluctuations track both adrenergic and cholinergic activity rather than a single transmitter. Lohani et al. (2022) showed that cortical cholinergic signals are spatially heterogeneous across behavioral states, and Neyhart et al. (2024) showed that local ACh depends on axon activity and local clearance kinetics. On the human side, Hansen et al. (2022) and Goulas et al. (2021) showed that receptor maps are structured regional priors, Wong et al. (2013) showed selected D2-receptor target engagement by an administered drug, and Koepp et al. (1998), Lippert et al. (2019), and Erritzoe et al. (2020) showed challenge- and window-limited dopamine or serotonin release proxies. What follows directly is that neuromodulation is not one measurement class.

Site rule for the ladder

On this site, mixed arousal proxy is read as a coarse covariate, local transmitter sensor as local calibration, receptor / transporter atlas as a regional prior, occupancy PET as target engagement, and displacement / release-sensitive PET as a challenge-limited release proxy. None of those rungs is promoted by default to the claim that the current whole-brain neuromodulatory state was directly measured.

Occupancy and displacement are different audit items

Wong et al. (2013) asked whether an administered antipsychotic occupied a selected receptor target in healthy humans. By contrast, Koepp et al. (1998), Lippert et al. (2019), and Erritzoe et al. (2020) used task- or drug-challenge-linked binding changes as dopamine or serotonin release proxies within bounded windows. Those designs do not answer the same question. On this site, occupancy PET is therefore audited as target engagement, whereas displacement PET is audited as endogenous release proxy under a named challenge.

PET routes still need tracer and quantification disclosure

PET-based proxy classes are not readable from the modality label alone. Naganawa et al. (2021) showed that human SV2A PET quantification depends on the tracer, arterial-versus-reference route, compartment model, and named scan window. Johansen et al. (2024) then built a healthy-human synaptic-density atlas, Shatalina et al. (2024) linked [11C]UCB-J DVRcs to task-related activity and cognition in healthy adults, Smart et al. (2021) showed that [11C]UCB-J binding measures remain unchanged during brief functional activation even when tracer influx rises with blood flow, and Holmes et al. (2022) found no measurable overall SV2A change 24 h after ketamine despite symptom improvement. Those papers do not answer the same question. Hansen et al. (2022) built a receptor atlas by collating PET data from more than 1,200 healthy individuals, so the resulting map is a normative chemoarchitectural prior rather than an individual's current transmitter state. Wong et al. (2013) quantified occupancy for an administered antipsychotic, while Koepp et al. (1998), Lippert et al. (2019), and Erritzoe et al. (2020) used challenge-linked binding changes as displacement-based release proxies. Therefore, on this site, PET-based routes must name the tracer, occupancy-versus-displacement design, challenge or administered drug plus dose when applicable, quantification model or validated window, anatomy / partial-volume handling when relevant, and the comparison family they actually instantiate before their claim ceiling is interpreted. The full SV2A-specific checklist now lives in Wiki: SV2A / synaptic-density PET route card.

The same caution extends to glia. Cahill et al. (2024) showed that local neurotransmitter inputs are minute-long encoded into broad astrocyte networks. That is a real advance, but it is still a slow-state / support-state route, not an automatic shortcut to whole-brain internal-state completeness.

7. Human maintenance-state routes also form a ladder

Another weakness that remained on this page was that it separated generic measurement stacks while still leaving recent human maintenance-state evidence too easy to compress into one sentence such as ``human in vivo observability is getting close.'' That is too weak. Shapson-Coe et al. (2024) pushed up local human nanoscale ultrastructure, Johansen et al. (2024) pushed up a regional synaptic-density atlas, Lucchetti et al. (2025) pushed up a whole-brain biochemical scaffold, Ren et al. (2015) pushed up a 31P metabolite / pH balance route, Ren et al. (2017) pushed up a model-conditioned 31P MT exchange-flux route, Guo et al. (2024) pushed up a whole-brain 31P NAD-content mapping route, Kaiser et al. (2026) pushed up a localized functional 31P NAD-dynamics route, Karkouri et al. (2026) pushed up a deuterium metabolite-mapping / absolute-quantification route, and Li et al. (2025) pushed up a deuterium kinetic-rate route. Qian et al. (2012) and Qian et al. (2025) pushed up macro ionic routes, Rzechorzek et al. (2022) pushed up macro thermal routes, van Blooijs et al. (2023) pushed up a tract-scale transmission-speed estimation route, and Baadsvik et al. (2024) pushed up macro myelin mapping. Human support-state evidence then splits again rather than converging into one route: Morgan et al. (2024) plus Padrela et al. (2025) push up a BBB water-exchange route, Chung et al. (2025) pushes up a tracer-specific BBB transport route, Zhao et al. (2020) pushes up a choroid-plexus perfusion route, Petitclerc et al. (2021) push up a blood-to-CSF water-transport route, Anderson et al. (2022) push up a choroid-plexus water-cycling route, Wu et al. (2026) push up an apparent BCSFB-exchange route, and Petitclerc et al. (2026) push up a simultaneous BBB-versus-BCSFB exchange route. Astrocyte PET also splits by route role: Villemagne et al. (2022) push up an SMBT-1 first-in-human MAO-B target-validation route, Villemagne et al. (2022) push up an SMBT-1 AD-spectrum disease-context route, Hiraoka et al. (2025) push up an SMBT-1 brain-quantification route, Mesfin et al. (2026) push up an SMBT-1 whole-body biodistribution route, Matsuoka et al. (2026) push up an SL25.1188 simplified-quantification route, Best et al. (2026) push up an SL25.1188 severity- and smoking-conditioned MAO-B route, and Tyacke et al. (2018) plus Livingston et al. (2022) push up an I2BS astrocyte PET route. Jaisa-Aad et al. (2024) plus Best et al. (2026) show that even MAO-B-linked interpretation remains cohort- and pathology-conditioned. Human neuroimmune PET then splits again rather than converging into one immune lane: Biechele et al. (2023) plus Wijesinghe et al. (2025) push up a TSPO disease-context / validation-bounded PET route, Horti et al. (2022) plus Ogata et al. (2025) push up a CSF1R route-setting PET route, and Yan et al. (2025) pushes up a COX-2 enzyme-defined PET route. Fultz et al. (2019) pushes up a macroscopic CSF-oscillation route, Kim, Huang, & Liu (2025) pushes up a parenchyma-CSF water-exchange route, Eide et al. (2023) pushes up an intrathecal-tracer / CSF-to-blood-clearance-capacity route, Hirschler et al. (2025) pushes up a CSF-mobility MRI route, and Dagum et al. (2026) pushes up a model-based overnight biomarker-efflux route. Human excitability-side evidence then splits again rather than converging into one route: Tallman et al. (2025) push up a local human clinical single-unit allocation route, but with firing explicitly treated as only an indirect excitability index; Huber et al. (2013), Kuhn et al. (2016), and Fehér et al. (2026) push up a sleep-homeostasis / plasticity-recalibration route; and Zrenner et al. (2018) plus Khatri et al. (2025) push up state-gated perturbation routes. What follows directly is that human evidence is layered across proxy classes, not a single near-direct route to current whole-brain maintenance-state. A second correction is also required: those rows are not all equally mature, routine, or deployment-ready, and they do not safely calibrate the same hidden-state family.

Human route Proxy class on this site Operational maturity / burden Safe calibrator role on this site What still remains latent Claim ceiling on this site
Local human nanoscale ultrastructure
Shapson-Coe et al. (2024)
Local ex vivo structural scaffold Destructive surgical-fragment route; not repeatable living-human acquisition. Structural scaffold only. Living whole-brain dynamics, current synaptic efficacy, ongoing maintenance-state, and cross-brain generalization. Local human structural scaffold. We do not promote it to living whole-brain state capture.
Regional synaptic-density PET atlas
Johansen et al. (2024)
Regional synaptic-density proxy Healthy-cohort atlas; tracer- and quantification-dependent. Bounded synaptic-density prior. Current synaptic efficacy, release probability, task-evoked momentary state change, synaptic-tag capture, and branch-local plasticity state. Regional synaptic-density proxy. We do not read it as a direct measurement of current synaptic function.
Whole-brain 1H-MRSI metabolic similarity scaffold
Lucchetti et al. (2025)
Parcel-level 1H-MRSI biochemical similarity scaffold Whole-brain cohort mapping with replication, but still a static five-metabolite similarity route. Bounded 1H-MRSI biochemical-organization scaffold. Current transcriptional controller, branch-local energetic reserve, cell-specific recovery logic, and local transmitter / glial microstate. Macro 1H-MRSI biochemical scaffold. It is not a local maintenance-state snapshot.
High-resolution 1H-MRSI metabolite-distribution route
Guo et al. (2025)
High-resolution 1H-MRSI metabolite-distribution proxy Ultrahigh-field route with extended spatiospectral encoding, subspace modeling, and explicit ghosting / aliasing / low-SNR handling burden. Bounded high-resolution metabolite-distribution proxy. Parcel-level similarity structure, deuterium absolute quantification, kinetic glucose-rate maps, current transcriptional controller, and branch-local energetic reserve. High-resolution metabolite-distribution proxy. It is not biochemical similarity, kinetic-rate imaging, or a local maintenance-state snapshot.
Human 31P-MRS metabolite / pH balance route
Ren et al. (2015)
Macro 31P metabolite / pH balance proxy Healthy resting cohort of 12 with ATP-synthesis, phosphorus-metabolite, pH, and relaxation estimates, but not a spatially fine compartment-control readout. Bounded phosphorus metabolite / pH balance proxy. Which dendritic branch lacks ATP reserve, where mitochondria are parked, which compartment is energetically fragile right now, and which fission / fusion state is active. Macro 31P metabolite / pH balance proxy. It does not become branch-local mitochondrial ground truth.
Human 31P MT exchange-flux route
Ren et al. (2017)
Model-conditioned macro 31P MT exchange-flux proxy Specialized 7 T route with a five-pool magnetization-transfer model rather than a route-free energetic snapshot. Bounded model-conditioned exchange-flux proxy. Route-independent metabolite / pH balance, whole-brain NAD content, task-evoked local NAD dynamics, branch-local mitochondrial residence, and direct controller identity. Model-conditioned macro 31P MT exchange-flux proxy. It does not become route-free energetic ground truth or branch-local mitochondrial ground truth.
Human 31P NAD-content mapping route
Guo et al. (2024)
Macro 31P NAD-content map proxy Specialized 7 T whole-brain route with subspace-based denoising, low-concentration spectral fitting, and long acquisition burden. Bounded whole-brain NAD-content map proxy. Task-evoked local NAD dynamics, branch-local mitochondrial residence, whole-brain moment-to-moment redox control, and task-general controller identity. Macro 31P NAD-content map proxy. It does not become localized functional dynamics or branch-local mitochondrial ground truth.
Human 31P functional NAD-dynamics route
Kaiser et al. (2026)
Localized functional 31P NAD-dynamics proxy Specialized 7 T task fMRS with prior fMRI localization and one occipital voxel rather than a whole-brain map. Bounded task-locked local NAD-dynamics proxy. Whole-brain NAD-content mapping, task-general energetic-controller identity, branch-local mitochondrial residence, and whole-brain moment-to-moment redox control. Localized functional 31P NAD-dynamics proxy. It does not become a whole-brain energetic map or branch-local mitochondrial ground truth.
Human deuterium metabolite-mapping / absolute-quantification route
Karkouri et al. (2026)
Macro deuterium metabolite-mapping / absolute-quantification proxy Specialized 7 T deuterium imaging with dedicated hardware and calibrated absolute-quantification pipeline; current human evidence remains limited-cohort and high-burden. Bounded deuterium metabolite-mapping proxy. Glucose-transport or metabolic-rate terms unless an explicit kinetic model is added, plus which dendritic branch lacks ATP reserve, where mitochondria are parked, which compartment is energetically fragile right now, and which fission / fusion state is active. Macro deuterium metabolite-mapping / absolute-quantification proxy. It does not become branch-local mitochondrial ground truth or kinetic-rate truth by default.
Human deuterium kinetic-rate imaging
Li et al. (2025)
Model-conditioned macro deuterium kinetic-rate proxy Specialized 7 T dynamic DMRSI with custom hardware, blood-input acquisition, and explicit kinetic model; current human evidence remains very small-cohort and high-burden. Bounded deuterium kinetic-rate proxy. Which dendritic branch lacks ATP reserve, where mitochondria are parked, which compartment is energetically fragile right now, and which fission / fusion state is active. Model-conditioned macro deuterium kinetic-rate proxy. It does not become branch-local mitochondrial ground truth or one generic deuterium map.
Human sodium MRI / ionic proxy
Qian et al. (2012); Qian et al. (2025)
Macro ionic proxy Specialized acquisition with emerging compartment-sensitive extensions rather than routine controller readout. Bounded ionic-burden proxy. Cell-specific chloride concentration, KCC2 / NKCC1 balance, extracellular K+ / Ca2+ / pH microdomains, local EGABA, and routine whole-brain intra- versus extracellular sodium partition. Macro ionic proxy. It is not direct ground truth of current chloride homeostasis.
Human brain thermometry
Rzechorzek et al. (2022)
Macro thermal proxy Living-human macro mapping route, but not a local thermal-controller assay. Bounded thermal-burden proxy. Cell-specific microtemperature, synapse-level heating burden, and local thermal controller state. Macro thermal proxy. It is not cell-specific thermal-state ground truth.
Human tract-scale transmission-speed estimation
van Blooijs et al. (2023)
Tract-scale timing-support proxy Development-sensitive human route with transfer-time and tract-geometry dependence rather than per-axon measurement. Bounded tract-scale timing-support proxy. Per-axon conduction controller, myelin-specific quantity, node / internode microgeometry, and local timing-state recovery. Tract-scale timing-support proxy. It is not myelin-specific ground truth or full timing-state recovery.
Human myelin bilayer mapping (specialized proof-of-principle)
Baadsvik et al. (2024)
Macro myelin proxy Proof-of-principle in two healthy volunteers on specialized high-performance hardware. Bounded myelin / timing-support proxy. Per-axon conduction controller, node / internode microgeometry, and local timing-state recovery. Macro myelin proxy. It is not full timing-state recovery.
Human clinical single-unit allocation route
Tallman et al. (2025)
Local clinical-unit allocation-related proxy Pathology-conditioned implanted-human route with local hippocampal single-unit coverage; not a routine noninvasive whole-brain assay. Bounded local human allocation-related calibrator. Whole-brain controller coverage, direct AIS / channel-state readout, and separation of pre-existing excitability from learning-induced change. Local clinical-unit allocation-related route. We do not promote it to a whole-brain excitability meter or direct controller measurement.
Human BBB water-exchange MRI
Morgan et al. (2024); Padrela et al. (2025)
Macro BBB water-exchange proxy ASL-based route with method dependence and explicit fitting burden; Kw and Tex are not route-free leakiness scalars. Bounded BBB water-exchange proxy. Tracer-specific permeability-surface-area, blood-CSF-barrier / choroid-plexus transport-family separation, cell-specific pericyte / endothelial controller identity, local capillary recruitment state, and synapse-resolved neurovascular support. Macro BBB water-exchange proxy. It is not tracer-specific transport truth or local controller ground truth.
Human tracer-specific BBB transport PET
Chung et al. (2025)
Tracer-specific BBB transport proxy Total-body high-temporal-resolution PET plus explicit kinetic-model burden; tracer choice changes the transport object. Bounded tracer-specific BBB transport proxy. Water-exchange time / rate, blood-CSF-barrier / choroid-plexus transport-family separation, cell-specific pericyte / endothelial controller identity, local capillary recruitment state, and synapse-resolved neurovascular support. Tracer-specific BBB transport proxy. It is not one generic BBB leakiness meter or local controller ground truth.
Human choroid-plexus perfusion route
Zhao et al. (2020)
Choroid-plexus perfusion proxy ASL-based human MRI with ROI-segmentation and long-T1 interpretation burden; perfusion rather than cross-boundary transport. Bounded choroid-plexus perfusion proxy. Blood-to-CSF water transport, choroid-plexus water cycling, apparent BCSFB exchange, simultaneous BBB-versus-BCSFB separation, solute-specific transport, and epithelial-controller identity. Choroid-plexus perfusion proxy. It is not blood-to-CSF transport truth or local controller ground truth.
Human blood-to-CSF transport route
Petitclerc et al. (2021)
Blood-to-CSF water-transport proxy Ultra-long-TE ASL route with labeled-water transport assumptions and specialized timing burden. Bounded blood-to-CSF transport proxy. Choroid-plexus perfusion, choroid-plexus water cycling, apparent BCSFB exchange, simultaneous BBB-versus-BCSFB separation, solute-specific transport, and epithelial-controller identity. Blood-to-CSF water-transport proxy. It is not one generic barrier-permeability scalar or local controller ground truth.
Human choroid-plexus water-cycling route
Anderson et al. (2022)
Choroid-plexus water-cycling proxy DCE-MRI route with contrast-leakage modeling and barrier-compartment assumptions. Bounded choroid-plexus water-cycling proxy. ASL blood-to-CSF transport, apparent BCSFB exchange, simultaneous BBB-versus-BCSFB separation, solute-specific transport, and epithelial-controller identity. Choroid-plexus water-cycling proxy. It is not route-free barrier transport truth.
Human apparent BCSFB exchange route
Wu et al. (2026)
Apparent BCSFB-exchange proxy REXI feasibility route with scan-rescan burden and apparent-exchange interpretation rather than direct solute flux. Bounded apparent BCSFB-exchange proxy. Boundary-separated BBB-versus-BCSFB exchange, solute-specific transport, epithelial-controller identity, and synapse-resolved neurovascular support. Apparent BCSFB-exchange proxy. It is not direct solute-transport truth or local controller ground truth.
Human simultaneous BBB-versus-BCSFB exchange route
Petitclerc et al. (2026)
Boundary-separated BBB-versus-BCSFB exchange proxy Dual-boundary ASL modeling route that estimates BBB and BCSFB exchange together; route-setting rather than routine deployment. Bounded boundary-separated BBB-versus-BCSFB exchange proxy. Solute-specific transport, local endothelial-versus-epithelial controller identity, capillary / choroid-plexus microterritory control, and synapse-resolved neurovascular support. Boundary-separated BBB-versus-BCSFB exchange proxy. It is not one generic barrier-permeability row or local controller ground truth.
Human SMBT-1 first-in-human MAO-B target-validation route
Villemagne et al. (2022)
MAO-B-related target-validation proxy Healthy-volunteer first-in-human dynamic PET with blockade evidence; still validation-stage rather than routine disease calibration. Bounded MAO-B target-validation proxy. AD-context transfer, stable brain-quantification regime, whole-body biodistribution, SL25.1188-related burden, I2BS-related burden, astrocyte-ensemble identity, minute-scale astrocyte-network state, and a route-free whole-brain astrocyte-state scalar. MAO-B target-validation proxy. It is not route-free astrocyte-state ground truth.
Human SMBT-1 AD-spectrum MAO-B disease-context route
Villemagne et al. (2022); Jaisa-Aad et al. (2024); Best et al. (2026)
MAO-B-related disease-context proxy Disease- and covariate-regime-dependent PET route; informative for pathology contrast, but not one general human baseline. Bounded MAO-B disease-context proxy. SL25.1188-related burden, I2BS-related burden, astrocyte-ensemble identity, minute-scale astrocyte-network state, whole-body biodistribution, and a route-free whole-brain astrocyte-state scalar. MAO-B disease-context proxy. It is not route-free astrocyte-state ground truth.
Human SMBT-1 brain-quantification route
Hiraoka et al. (2025)
MAO-B-related brain-quantification proxy Dedicated quantification study with explicit kinetic-versus-simplified modeling burden; route-setting rather than disease-general deployment. Bounded MAO-B brain-quantification proxy. Cross-centre transfer, disease-context calibration, whole-body biodistribution, SL25.1188-related burden, I2BS-related burden, astrocyte-ensemble identity, and a route-free whole-brain astrocyte-state scalar. MAO-B brain-quantification proxy. It is not route-free astrocyte-state ground truth.
Human SMBT-1 whole-body biodistribution route
Mesfin et al. (2026)
MAO-B-related whole-body biodistribution / tracer-burden proxy Healthy-volunteer whole-body dynamic PET with limited cohort and long acquisition burden. Bounded whole-body biodistribution / tracer-burden proxy. Brain target validity, disease-context contrast, SL25.1188-related burden, I2BS-related burden, astrocyte-ensemble identity, minute-scale astrocyte-network state, and a route-free whole-brain astrocyte-state scalar. Whole-body biodistribution / tracer-burden proxy. It is not route-free astrocyte-state ground truth.
Human SL25.1188 MAO-B route
Matsuoka et al. (2026); Best et al. (2026)
SL25.1188-related MAO-B proxy Simplified-quantification and cohort-severity / smoking-conditioned PET route; not a route-free healthy baseline. Bounded SL25.1188-related MAO-B proxy. SMBT-1 target-validation / disease-context / brain-quantification / whole-body-biodistribution roles, I2BS-related burden, astrocyte-ensemble identity, minute-scale astrocyte-network state, and a route-free whole-brain astrocyte-state scalar. SL25.1188-related MAO-B proxy. It is not route-free astrocyte-state ground truth.
Human I2BS astrocyte PET route
Tyacke et al. (2018); Livingston et al. (2022)
I2BS-related astrocyte proxy Tracer-specific PET with idazoxan-competition interpretation, quantification-model burden, and disease-regime dependence. Bounded I2BS-related astrocyte proxy. MAO-B-related target-validation / disease-context / quantification / whole-body-biodistribution / SL25.1188 roles, astrocyte-ensemble identity, minute-scale astrocyte-network state, and a route-free whole-brain astrocyte-state scalar. I2BS-related astrocyte proxy. It is not route-free astrocyte-state ground truth.
Human TSPO disease-context / validation-bounded PET
Biechele et al. (2023); Wijesinghe et al. (2025)
TSPO disease-context / validation-bounded neuroimmune proxy Target- and disease-context-specific PET with cross-species / postmortem validation burden; not a universal activation-state meter. Bounded TSPO disease-context / validation-bounded proxy. CSF1R route-setting, COX-2 enzyme-defined burden, cell-specific immune-controller identity, causal cytokine state, and local synapse-support mechanism. TSPO disease-context / validation-bounded neuroimmune proxy. It is not route-free microglia-state ground truth.
Human CSF1R route-setting PET
Horti et al. (2022); Ogata et al. (2025)
CSF1R route-setting neuroimmune proxy First-in-human and arterial-input / tracer-model burden; route-setting rather than routine disease deployment. Bounded CSF1R route-setting proxy. TSPO disease-context transfer, COX-2 enzyme-defined burden, cell-specific immune-controller identity, causal cytokine state, and local synapse-support mechanism. CSF1R route-setting neuroimmune proxy. It is not route-free immune-state ground truth.
Human COX-2 enzyme-defined PET
Yan et al. (2025)
COX-2 enzyme-defined neuroimmune proxy First-in-human blockade-defined PET with selected healthy-participant burden; not a route-free inflammation meter. Bounded COX-2 enzyme-defined proxy. TSPO disease-context transfer, CSF1R route-setting, cell-specific immune-controller identity, causal cytokine state, and local synapse-support mechanism. COX-2 enzyme-defined neuroimmune proxy. It is not route-free immune-state ground truth.
Human macroscopic CSF-oscillation proxy
Fultz et al. (2019)
Sleep-state CSF-oscillation proxy Fast-fMRI plus EEG sleep route; macro oscillation rather than a solute-specific clearance assay. Bounded sleep-state CSF-oscillation proxy. Net molecular flux, parenchyma-CSF exchange, CSF-to-blood clearance capacity, cell-specific immune control, and local synaptic maintenance. Sleep-state CSF-oscillation proxy. It is not direct protein-clearance truth.
Human parenchyma-CSF water-exchange proxy
Kim, Huang, & Liu (2025)
Parenchyma-CSF water-exchange proxy Small-cohort noninvasive MRI route with exchange-model burden; not a protein-specific efflux assay. Bounded parenchyma-CSF water-exchange proxy. Protein-specific efflux, CSF-to-blood clearance capacity, cell-specific immune control, and local synaptic maintenance. Parenchyma-CSF water-exchange proxy. It is not protein-specific clearance truth.
Human respiration-conditioned CSF net-flow route
Lim et al. (2025)
Respiration-conditioned CSF net-flow proxy Awake-state 2D phase-contrast MRI route with plane-specific and respiration-regime burden; not a route-free whole-brain circulation assay. Bounded respiration-conditioned net-flow proxy. Route-free whole-brain bulk circulation, protein-specific efflux, cell-specific immune control, and local synaptic maintenance. Respiration-conditioned net-flow proxy. It is not route-free clearance truth.
Human exercise-conditioned contrast-influx / meningeal-lymphatic route
Yoo et al. (2025)
Exercise-conditioned contrast-influx / meningeal-lymphatic proxy Long-term exercise intervention with intravenous-contrast dynamic-T1 / black-blood / IR-ALADDIN burden; not a natural-sleep baseline route. Bounded intervention-conditioned contrast-influx / meningeal-lymphatic proxy. Natural-sleep whole-brain clearance truth, route-free local immune control, and local synaptic maintenance. Exercise-conditioned contrast-influx / meningeal-lymphatic proxy. It is not all-purpose clearance truth.
Human intrathecal tracer / CSF-to-blood clearance proxy
Eide et al. (2023)
Intrathecal-tracer / CSF-to-blood-clearance-capacity proxy Intrathecal tracer plus contrast MRI and population-pharmacokinetic-model burden; not a routine natural-sleep route. Bounded intrathecal-tracer / CSF-to-blood-clearance-capacity proxy. Natural-sleep whole-brain clearance truth, cell-specific immune control, and local synaptic maintenance. Intrathecal-tracer / CSF-to-blood-clearance-capacity proxy. It is not a route-free glymphatic scalar.
Human CSF-mobility MRI
Hirschler et al. (2025)
CSF-mobility proxy Specialized 7 T MRI route; mobility rather than net flow or direct solute clearance. Bounded CSF-mobility proxy. Net solute flux, CSF-to-blood clearance capacity, cell-specific immune control, and local synaptic maintenance. CSF-mobility proxy. It is not direct flux truth.
Human model-based overnight biomarker efflux
Dagum et al. (2026)
Model-based biomarker-efflux proxy Investigational-device route with multicompartment modeling and crossover-protocol burden. Bounded model-based biomarker-efflux proxy. Local immune-controller identity, local synaptic maintenance, and route-free whole-brain clearance truth. Model-based biomarker-efflux proxy. It is not local maintenance-controller ground truth.
Human sleep-homeostasis / plasticity proxy
Huber et al. (2013); Kuhn et al. (2016); Fehér et al. (2026)
Perturbation-conditioned maintenance proxy Intervention-backed human route, but still controller-indirect and regime-limited. Bounded excitability / plasticity-support proxy. Which cell type, AIS / channel change, synapse, glial controller, or recovery controller produced the effect. Perturbation-conditioned maintenance proxy. It is not direct readout of the responsible excitability controller.
Human state-gated perturbation proxy
Zrenner et al. (2018); Khatri et al. (2025)
State-gated perturbation proxy Operationally real closed-loop human route, but still mechanism-indirect. Bounded state-gated excitability proxy. AIS geometry, channel distribution, cell-specific allocation state, and long-horizon recovery controller. State-gated perturbation proxy. It is not direct measurement of the excitability mechanism itself.
Still lacking a comparable in vivo whole-brain human route Still explicitly latent No comparable living-human whole-brain route in the reviewed stack bundle. No safe calibrator role yet. These layers still cannot be promoted from human evidence to comparable whole-brain in vivo ground truth on the basis of the reviewed measurement classes alone. Keep them explicitly latent or externally calibrated; do not auto-fill them from the proxy rows above.
Proxy class, operational maturity, and calibrator role have to be logged separately

The key operational criticism is that a route can be real without being broad. Johansen et al. (2024) built an atlas from 33 healthy participants calibrated against postmortem autoradiography, but that still calibrates a synaptic-density prior rather than task-time synaptic efficacy. Lucchetti et al. (2025) derived a five-metabolite similarity scaffold from 51 healthy adolescents with an independent replication sample of 13, but that still calibrates a biochemical organization scaffold rather than an energetic controller. Ren et al. (2015) measured ATP synthesis, phosphorus metabolites, and pH in 12 healthy participants, which calibrates only a bounded energetic-balance proxy. Ren et al. (2017) measured PCr→γ-ATP and Pi→γ-ATP exchange flux under a 5-pool MT model in six subjects, which calibrates only a bounded model-conditioned exchange-flux proxy. Guo et al. (2024) reported a whole-brain NAD-content map at 7 T under subspace denoising and long acquisitions, while Kaiser et al. (2026) reported a task-evoked local NAD+ route in a functionally localized occipital voxel of 25 healthy volunteers. Those are real 31P routes, but they still calibrate only a bounded metabolite / pH balance proxy, a bounded model-conditioned exchange-flux proxy, a bounded whole-brain NAD-content map, or a bounded task-locked local NAD-dynamics proxy. Karkouri et al. (2026) reported absolute deuterated metabolite maps at 7 T with a dedicated calibration pipeline, while Li et al. (2025) reported deuterium kinetic-rate maps under blood-input and explicit kinetic modeling in a five-participant cohort. Those are real routes, but they still calibrate only bounded deuterium metabolite-mapping or bounded deuterium kinetic-rate proxies. van Blooijs et al. (2023) estimated tract-scale transmission speed in a developmental human route, while Baadsvik et al. (2024) showed myelin-bilayer mapping in two healthy volunteers on specialized hardware. Those are real timing-support advances, but they still calibrate only a bounded tract-scale timing-support proxy or a bounded macro myelin proxy, not per-axon conduction control. Tallman et al. (2025) then added a local human clinical-unit allocation route in epilepsy patients, but one that still stops at a bounded local calibrator because firing is only an indirect index of excitability and coverage is not whole-brain. Huber et al. (2013), Kuhn et al. (2016), and Fehér et al. (2026) calibrate only a bounded perturbation-conditioned maintenance proxy, while Zrenner et al. (2018) plus Khatri et al. (2025) calibrate only a bounded state-gated corticospinal / plasticity proxy. Morgan et al. (2024) plus Padrela et al. (2025) calibrate only a bounded BBB water-exchange proxy, while Chung et al. (2025) calibrates only a bounded tracer-specific BBB transport proxy. Zhao et al. (2020), Petitclerc et al. (2021), Anderson et al. (2022), Wu et al. (2026), and Petitclerc et al. (2026) then calibrate only bounded choroid-plexus perfusion, blood-to-CSF transport, choroid-plexus water-cycling, apparent BCSFB exchange, or boundary-separated BBB-versus-BCSFB exchange proxies, not one generic barrier-support meter. Astrocyte PET also splits by route role: Villemagne et al. (2022) calibrate only a bounded MAO-B target-validation proxy, Villemagne et al. (2022) plus Jaisa-Aad et al. (2024) and Best et al. (2026) calibrate only a bounded MAO-B disease-context proxy, Hiraoka et al. (2025) calibrate only a bounded MAO-B brain-quantification proxy, Mesfin et al. (2026) calibrate only a bounded whole-body biodistribution / tracer-burden proxy, Matsuoka et al. (2026) plus Best et al. (2026) calibrate only a bounded SL25.1188-related MAO-B proxy, and Tyacke et al. (2018) plus Livingston et al. (2022) calibrate only a bounded I2BS-related astrocyte proxy. Human neuroimmune PET also splits by target class and route role: Biechele et al. (2023) plus Wijesinghe et al. (2025) calibrate only a bounded TSPO disease-context / validation-bounded proxy, Horti et al. (2022) plus Ogata et al. (2025) calibrate only a bounded CSF1R route-setting proxy, and Yan et al. (2025) calibrates only a bounded COX-2 enzyme-defined proxy. Fultz et al. (2019), Kim, Huang, & Liu (2025), Lim et al. (2025), Yoo et al. (2025), Eide et al. (2023), Hirschler et al. (2025), and Dagum et al. (2026) then calibrate only sleep-state CSF oscillation, parenchyma-CSF water exchange, respiration-conditioned CSF net flow, exercise-conditioned contrast influx / meningeal-lymphatic flow, intrathecal-tracer / CSF-to-blood-clearance capacity, CSF mobility, or model-based biomarker efflux respectively, not one generic clearance-support meter. Therefore, this page now treats proxy class, operational maturity, and safe calibrator role as separate metadata that all have to be stated before claim ceilings are interpreted.

Spectroscopy rows also split by quantity type and model burden

The spectroscopy rows cannot be read as one proxy family. Lucchetti et al. (2025) constrained parcel-level correlation structure across five metabolites, Guo et al. (2025) constrained high-resolution 1H-MRSI metabolite-distribution maps under explicit reconstruction and artifact-control burden, Ren et al. (2015) constrained ATP synthesis / phosphorus-metabolite balance / pH, Ren et al. (2017) constrained PCr→ATP and Pi→ATP exchange flux under a magnetization-transfer model, Guo et al. (2024) constrained whole-brain intracellular NAD content, Kaiser et al. (2026) constrained task-evoked local NAD+ dynamics, Karkouri et al. (2026) constrained absolute deuterated-metabolite concentrations under a dedicated quantification pipeline, and Li et al. (2025) constrained glucose-transport and kinetic-rate maps under a blood-input model. Even within 1H-MRSI mapping, Bhogal et al. (2020), Wright et al. (2022), Baboli et al. (2024), and Guo et al. (2025) show that lipid suppression, tissue-fraction correction, water / relaxation modeling, ghosting, aliasing, and low-SNR handling materially shape the inferred maps. Therefore, this site does not allow ``human spectroscopy evidence'' as a single proxy label. The quantity type, cohort burden, hardware burden, and model burden all have to be named before the claim ceiling is read.

Site rule for human proxy classes

On this site, human-side summaries must name the proxy class explicitly. ``Human evidence exists'' is too coarse. The summary has to tell the reader whether the result is a local structural scaffold, regional synaptic-density proxy, macro 1H-MRSI biochemical similarity scaffold, high-resolution 1H-MRSI metabolite-distribution proxy, macro 31P metabolite / pH balance proxy, macro 31P MT exchange-flux proxy, macro 31P NAD-content map proxy, localized functional 31P NAD-dynamics proxy, macro deuterium metabolite-mapping / absolute-quantification proxy, macro deuterium kinetic-rate proxy, local clinical-unit allocation-related proxy, perturbation-conditioned maintenance proxy, state-gated perturbation proxy, tract-scale transmission-speed proxy, quantity-defined macro ionic / thermal / myelin proxy family, macro BBB water-exchange proxy, tracer-specific BBB transport proxy, choroid-plexus perfusion proxy, blood-to-CSF water-transport proxy, choroid-plexus water-cycling proxy, apparent BCSFB-exchange proxy, boundary-separated BBB-versus-BCSFB exchange proxy, MAO-B target-validation / disease-context / brain-quantification / whole-body-biodistribution / SL25.1188 astrocyte proxies, I2BS-related astrocyte proxy, TSPO disease-context / validation-bounded neuroimmune proxy, CSF1R route-setting neuroimmune proxy, COX-2 enzyme-defined neuroimmune proxy, sleep-state CSF-oscillation proxy, parenchyma-CSF water-exchange proxy, respiration-conditioned CSF-net-flow proxy, exercise-conditioned contrast-influx / meningeal-lymphatic proxy, intrathecal-tracer / CSF-to-blood-clearance-capacity proxy, CSF-mobility proxy, or model-based biomarker-efflux proxy. When the route is still specialized, model-dependent, or small-cohort, that maturity limit must be stated alongside the proxy class. And when the route calibrates only one bounded hidden-state family, that calibrator role must be written explicitly rather than inherited from the modality label.

Same-subject still does not solve the bridge by itself

One more shortcut remained too easy on this page: to read same subject or same brain as if several human rows had already become one state sample. The primary literature does not support that shortcut. Lu et al. (2023) showed that preservation route changes extracellular-space retention and native geometry, Shapson-Coe et al. (2024) remained a rapidly preserved local surgical fragment rather than a living whole-brain route, and MICrONS Consortium et al. (2025) remained a sequential same-brain pipeline rather than same-time capture. Therefore, if a human proxy bundle crosses live and ex vivo or separated physiological regimes, this site now asks for a State-Continuity Bridge Card that names elapsed time, regime continuity, coordinate-transfer burden, and residual drift ceiling before same-state language is allowed.

Why this ladder matters operationally

The danger is not only philosophical overreach. If these rows are compressed into one sentence, readers can silently replace ``human proxy-rich evidence'' with ``human near-direct maintenance-state observation.'' This site does not allow that rephrasing. The missing layers above stay latent until a comparable whole-brain in vivo human route or an explicit external-calibration route is shown.

8. Proxy-rich human evidence still does not become state-complete by composition

A remaining weakness after separating proxy class, operational maturity, and calibrator role was that a reader could still mentally add the strongest human rows together and conclude that the hidden-state problem is almost solved. The primary literature does not support that shortcut. The rows above live on different spatial units, time windows, and inference layers, and several of the strongest demonstrations are still specialized or model-heavy. The safe reading on this site is therefore not ``the proxies add up to completeness,'' but ``the proxies reduce different error terms and still leave a fusion problem.''

Compositional shortcut to block Why the cited literature does not support it Operational correction on this site
``Atlas + proxy = current individual state'' Johansen et al. (2024) and Hansen et al. (2022) are atlas / cohort resources. They constrain regional organization and synaptic-density distribution, but they do not directly read one individual's current task-time state. Write atlas or normative prior explicitly; do not phrase these rows as current-state measurement.
``Several macro proxies = one local controller'' Li et al. (2025), Rzechorzek et al. (2022), Qian et al. (2025), and Baadsvik et al. (2024) constrain different macro energetic, thermal, ionic, or myelin variables. They do not identify branch-local ATP reserve, current chloride set point, or per-axon conduction control as one merged mechanism. Keep local controllers explicit in the Observability Budget; do not auto-fill them from macro proxy coexistence.
``Support-state proxy = direct maintenance controller'' Lim et al. (2025), Yoo et al. (2025), Hirschler et al. (2025), and Dagum et al. (2026) constrain respiration-conditioned net flow, exercise-conditioned contrast influx / meningeal-lymphatic flow, CSF mobility, or brain-to-plasma biomarker efflux under route-specific acquisition and model assumptions, not cell-specific immune control or synaptic maintenance logic. Read them as support-state evidence only; leave local maintenance control latent unless another calibrated route closes it.
``Cross-stack fusion adds only observables'' Wei et al. (2020) made the model burden in EEG-fMRI fusion explicit, while Vafaii et al. (2024) and Chen et al. (2025) showed that simultaneous multimodal recordings can carry both common and divergent structure across modalities. Fusion therefore combines model burdens and mismatch risks as well as direct observables. Log the fusion model, external calibration source, and abstention boundary separately instead of treating multimodal combination as self-justifying; on this site that package is the Fusion Card.
``Different scales acquired somewhere imply same-subject completeness'' Shapson-Coe et al. (2024) is local ex vivo nanoscale human cortex, whereas Li et al. (2025) and Baadsvik et al. (2024) are small-cohort specialized in vivo macro routes. The cited papers do not demonstrate same-subject, same-time, whole-brain cross-stack state identification. Reserve stronger wording for studies that disclose same-subject co-registration, same-regime alignment, and externally validated cross-stack fusion.
``Same-subject sequential pipeline = same-state multistack sample'' Lu et al. (2023) showed that preservation route changes geometry, Shapson-Coe et al. (2024) remained a local ex vivo fragment, and MICrONS Consortium et al. (2025) remained a sequential same-brain workflow rather than same-time capture. The cited papers do not show that specimen identity alone closes time, regime, or registration drift. Attach a State-Continuity Bridge Card that names elapsed time, regime continuity, coordinate transfer, and residual drift ceiling before promoting the bundle above proxy-rich evidence.
Composition rule on this site

This site now treats proxy-rich human evidence as a real advance over a single proxy class, but still below same-subject, cross-stack, externally calibrated state identification. To move upward, a paper or benchmark package has to disclose co-registration scope, perturbation alignment, clock / lag audit, quantification models, external calibration, and what latent states remain unmatched. If the bridge is sequential across live and ex vivo or across separated physiological regimes, it also has to disclose elapsed time, regime continuity, coordinate transfer, and residual drift ceiling through the State-Continuity Bridge Card. On this site, multimodal combination itself is formalized as the Fusion Card. That ranking is an inference from the primary literature summarized above.

Practical rules arising from this criticism

Rule

  • Write the measurement stack in the augmentation claim:Instead of saying "added transcriptomic label", distinguish between whole-brain atlas, patch-seq bridge, or same-brain link.
  • Don't mix atlas / bridge / scaffold / local twin / proxy calibration:Fix which kind of advance is the same "advance".
  • Don't make multimodal a synonym for state-complete:Include in the text what latent state still remains.
  • Do not compress same-brain functional connectomics into one solved route:Name the sequential bridge, label source, synaptic-state evidence class, and whether extra recordings or perturbations were needed to reduce dynamical degeneracy.
  • In human-side summaries, name proxy class, operational maturity, and calibrator role:Do not compress local ultrastructure, synaptic-density PET, biochemical scaffold, perturbation-conditioned plasticity/state-gated perturbation routes, energetic / ionic / thermal / myelin, BBB, blood-CSF-barrier / choroid-plexus, astrocyte, neuroimmune, or clearance routes into one direct route.
  • Do not read proxy accumulation as automatic state-completeness:Cross-stack fusion still needs same-subject alignment, model disclosure, external calibration, and abstention boundaries.
  • Do not read same-subject wording as same-state when the bridge is sequential:Require elapsed time, regime continuity, coordinate transfer, and residual drift disclosure.
  • When filling in unobserved states, write ``estimated'': If threshold / gain / set point is auto-completed from cell type, write ``latent inference''.
  • Do not promote BOLD / fNIRS amplitude to neural difference without hemodynamic audit:Write vascular-state / CVR calibration route or abstention explicitly.
  • Prohibit expressions that exceed the claim ceiling:For example, do not write EM alone as emulation-complete, Patch-seq as whole-brain state-complete, pupil as transmitter ground truth, receptor atlas as current transmitter state, occupancy PET as whole-brain transmitter-state readout, or displacement PET as whole-brain neuromodulatory ground truth.
Current stack What to add next Stronger argument Claim to stop
EEG / MEG / fMRI External ground truth, invasion record, structure/function correspondence of the same individual, and intervention response. The rationale for moving from macro decode to weak L2 is a little stronger. Stop cell/synapse state sufficiency, whole-brain WBE, and state-complete claims.
whole-brain atlas Patch-seq, same-brain physiology, perturbation/recovery log. Easier to connect cell-type prior and spatial prior to local parameter prior. Turn off the sufficiency of current network state and longitudinal maintenance-state.
volume EM Same-brain function, cell-type bridge, perturbation, uncertainty are public. It is easier to proceed from structural scaffold to local conditional prediction. Stop rephrasing connectome-complete as emulation-complete.
same-brain functional connectomics Direct label assay or explicit label-transfer route, current synaptic-state assay, extra recordings / perturbations, and bridge disclosure. It becomes easier to separate local structure-function scaffold, morphology-bridged label transfer, current synaptic-state evidence, and identifiable dynamics. Stop whole-brain twin, current synaptic-state, direct transcriptomic-truth, and unique-dynamics claims from the modality label alone.
mixed proxy / transmitter sensor / receptor atlas / occupancy PET / displacement PET cross-stack calibration, ligand / drug / challenge / dose disclosure, cross-state validation, and abstention boundary. It becomes easier to distinguish coarse arousal covariate, local calibration, regional prior, exogenous target engagement, and challenge-limited release proxy. Stop whole-brain transmitter-field ground truth and receptor-family-complete internal-state claims.
human maintenance-state proxies class-labeled submission, calibrator-role disclosure, external calibration route, cross-stack comparison, and bridge disclosure when acquisition is sequential. It becomes easier to separate local scaffold, synaptic-density proxy, biochemical scaffold, perturbation-conditioned plasticity proxy, energetic / ionic / thermal / myelin, BBB, blood-CSF-barrier / choroid-plexus, astrocyte, neuroimmune, and clearance proxy classes, the bounded hidden-state family each route safely calibrates, and still-missing human routes. Stop near-direct human maintenance-state and state-complete claims.

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