neuroscience.
127 of 1538 NOTE documents. Back to the full index.
| # | Title | Summary | Status |
|---|---|---|---|
| NOTE-029 v2 | Krauska & Lau 2023, moving away from lexicalism | The authors argue that lemma-based production models encode two lexicalist assumptions: a morphology/syntax split, and a stored meaning–syntax–form “triad”. On that basis the models mishandle Inuktitut polysynthesis, separable Vietnamese idiomatic collocations, Hiaki number suppletion and English verb–object idioms. Updating the representations (treelets) is not enough, because the algorithms — separate lexical retrieval and structure building, word-sized increments — also have to change. They sketch an 8-stage non-lexicalist model and derive qualitative aphasia predictions from it. There are no new data and no implementation. | Read |
| NOTE-052 v2 | Consciousness in AI: indicator properties | The report assumes computational functionalism and takes a “theory-heavy” approach. From it the authors derive 14 indicator properties: RPT-1–2, GWT-1–4, HOT-1–4, AST-1, PP-1 and AE-1–2. The claim for them is only that more of them raises the probability of consciousness. They assess a handful of systems against subsets of the list and conclude that no current system “appears to be a strong candidate”. Transformer LLMs have “only a relatively weak case” for any GWT indicator, because a single forward pass has no recurrence or global broadcast. Perceiver arguably has GWT-1, GWT-2 and half of GWT-4 but lacks broadcast. Among the embodied agents, AdA is the likeliest to meet AE-2. Most indicators could be built with standard ML techniques. The abstract’s “no current AI systems are conscious” is stronger than anything the body shows. | Read |
| NOTE-054 v2 | Brain states across spacetime via whole-brain models | This is a narrative review with no new data, model or quantitative synthesis. It argues that healthy waking brain dynamics sit in a metastable regime near criticality, which whole-brain models (connectome-coupled Hopf oscillators, weakly coupled, at the edge of instability) reproduce. On its “activity landscape” picture, depression deepens particular attractors and psychedelics flatten the landscape. The depression side rests on three cited fMRI studies, one of them in remitted patients, and the review itself says “further studies will be required”. | Read |
| NOTE-067 v2 | The sound of an axon’s growth | The paper proposes that an axon can set its length from motor-generated oscillations without reading their frequency. Two Hill-type stages turn the period (which grows with length L) into a shape change and then into a change in the mean of a contractility signal R. Coupling growth-cone protrusion (v_g c_I) against R-driven contraction (v_s c_R) then gives a stable length: about 125 µm with sub-µm (< 1 %) oscillation for the Fig. 4a parameters. In part of parameter space the final length rises as kinesin influx J0 falls, or as dynein coupling J_O falls, qualitatively as in experiments. | Read |
| NOTE-075 v2 | Surface optimization in physical networks | The degree counts in Fig. 1d show k = 4 nodes making up 4.6–17.7% of branch points across the six datasets. The pooled 16.6% is 96% human-neuron nodes. Bifurcation angles also fail to peak at 2π/3. From this the authors infer that local branching minimises sleeve surface area under a minimum circumference w, not wire length. For a regular tetrahedron their numerical minimiser merges two bifurcations into a trifurcation at χ = w/r ≈ 0.83, and a thin branch sprouts orthogonally below ρ = w′/w ≈ 0.6. Per-dataset empirical thresholds are ρ_th = 0.52–0.92. The “exact mapping” to string-theory worldsheets covers only the unconstrained minimal-area problem. The SI says the implemented method yields surfaces that are only locally area-minimising (§5). | Read |
| NOTE-091 v2 | Pernu — Mental causation via neuroprosthetics? | The interventionist/difference-making case for nonreductive mental causation from BCIs (List & Menzies 2009; Menzies 2015; Woodward 2008a,b, 2017) misplaces multiple realisation. What the ensemble recordings show is that one cortical-level variable N (the ensemble’s average firing) is realised by many single-neuron patterns N1, N2. Each intention M corresponds to one value of N. So the counterfactual contrast “∼M □→ ∼B true, ∼N □→ ∼B false” fails, and neuroprosthetics supports mental causation only by identifying M with N, not nonreductive physicalism. | Read |
| NOTE-106 v3 | Angius et al. — Making sense of transformer success | Current attempts to explain transformer language models’ competence fall into three kinds, and the paper maps each onto an explanatory form from philosophy of cognitive science: machine psychology is Cummins-style functional analysis, induction-head work is Machamer–Darden–Craver mechanistic explanation, and NLM–fMRI brain-score studies are a bidirectional “co-simulation”. Its only thesis is that these do not differ from how cognitive science explains humans. Functional analyses are to be reduced to mechanisms as “mechanism sketches”. The paper rests on existing literature and adds no new analysis or data. | Read |
| NOTE-146 v2 | Winkielman et al. — The coherent and fluent mind | An opinion piece proposing an extra route to the unity of consciousness across the senses. Different modalities feed one global, content-nonspecific experience of processing quality (fluency, familiarity, coherence), and this integrated feeling then enters decisions about its source and relevance. The main support is the authors’ own finding (Ziembowicz et al. 2013; three experiments) that coherent but unrelated background patterns in one modality made targets in another modality be judged more “regular”, “familiar” and “possible”. The authors state that direct evidence is still needed that such effects run through changed experience and that its integration is causal (p. 2). | Read |
| NOTE-150 v2 | Ivy & Mroczko-Wąsowicz — Framing effects in perception | A conceptual proposal with no new data. “Perceptual frames” are learned adaptations of the perceptual system, installed diachronically, often top-down, and then operating bottom-up. They let perceivers given identical input individuate different perceptual objects (the Bach motif, the radiologist’s tumour, the Teufel et al. two-tone image). So cognition shapes the perceptual system even if it is left open whether any single percept is penetrated. Support is a survey of others’ findings (Ernst & Banks 2002 cue weighting, prism adaptation, Teufel et al. 2018, expert anticipation) read through the frame concept. | Read |
| NOTE-165 v2 | Martínez — information-processing view of representation | A position paper, not an argument to a conclusion. It proposes that representations are signals adapted to transmit information for its own sake (Transmission), and that the evidence for this is efficiency in trading off rate, distortion and coder complexity (RDC Trade-Off). It supports the proposal by showing that cognitive scientists already attribute representational status on those grounds: compression, error protection, and explicitness understood as ease of decoding. It proves no theorem and reports no data of its own. | Read |
| NOTE-169 v2 | Seth — Conscious AI and biological naturalism | Seth argues that conscious AI needs computational functionalism and substrate flexibility extending to silicon, and that both are doubtful (§3.9). Against them he gives a positive, explicitly non-vitalist case, running from interoceptive predictive processing through the free energy principle to autopoiesis, that consciousness is a property “of only (but not necessarily all) living systems” (§4). He concludes that real artificial consciousness is “unlikely along current trajectories” and would need “living AI” (§5.8), while conscious-seeming AI is “almost certain” and may be “cognitively impenetrable” (§6.2). He concedes that “my case is not watertight” (§5.8). | Read |
| NOTE-219 v2 | Duality of Bures and Shape Distances | The Procrustes shape distance between two representations (optimal rotational alignment of units) equals the Bures distance between their centred linear kernel matrices, so the rotation-invariant geometry of a representation is exactly the geometry of its kernel, and through Uhlmann’s theorem the fidelity of two kernels is the maximum overlap over all representations consistent with them. | Superseded — by NOTE-753 |
| NOTE-225 v2 | What Similarity Measures Imply about Decodability | For linear readouts regularised by w ↦ wᵀG(X)w, the optimal decoded signal is K_X z with K_X = X G(X)⁻¹ Xᵀ / M. The expected alignment of two networks’ optimal readouts is therefore Tr(K_X K_z K_Y), which recovers linear CKA, CCA, GULP and ENSD as average decoding similarities. Procrustes distance bounds the average decoding distance from both sides, with constants set by a participation ratio. | Superseded — by NOTE-834 |
| NOTE-242 v2 | Attention Approximates Sparse Distributed Memory | Kanerva’s SDM read weights each stored pointer by the number of neurons in the intersection of two Hamming balls of radius d. The paper shows that this weight is roughly log-linear in Hamming distance for close patterns. As a result, with L²-normalised vectors and a regression-fitted β, softmax attention reproduces SDM’s retrieval behaviour on random and learnt-projection data (App. B.7). Two things are weaker than they look. The analytic derivation (App. B.2, Eqs. 16–21) gets the exponent wrong: by my recomputation its β is ≈2–2.5× too small. The biological case is Kanerva’s 1988 cerebellar mapping, restated rather than re-argued. It also needs r = 2⁶⁴ ≈ 1.8×10¹⁹ neurons in the Attention setting, which the paper itself calls “biologically implausible” (App. B.5). | Read |
| NOTE-316 | A decision-making theory of visual detection | Tanner and Swets model visual detection as testing a statistical hypothesis. The observer compares one sample of neural activity with a cutoff, and signal+noise and noise are Gaussian with equal variance, separated by d′ (the mean difference in noise-SD units, defined as the square root of Peterson and Birdsall’s d). The cutoff moves along a curve of P_SN(A) against P_N(A) (the curve now called the ROC; for d′ = 1 it passes through (.16, .50), (.50, .84) and (.84, .98)). The optimal operating point is where the slope equals β = [(1−P(SN))/P(SN)]·[(V_N·CA+K_N·A)/(V_SN·A+K_SN·CA)]. The 4AFC prediction is P(C)=∫F(x)³g(x)dx. With three paid observers, d′ estimated from yes-no data predicted 4AFC accuracy. The “false alarms are guesses” (high-threshold) hypothesis is rejected: false-alarm rate correlated with chance-corrected thresholds (ρ = .30, .71, .67; combined p ≪ .001), and all 12 fitted yes-no scatter lines miss the point (1, 1). | Read |
| NOTE-321 v3 | The two dragons of cognition: recursive condensation for predictive processing | A Hypothesis-and-Theory essay, the cognitive statement of Li’s structural-learning programme. Intelligence pays once for exploratory search, condenses the result into stable discrete tokens, and then navigates cheaply. The cortex and the sleep rhythms are proposed as this cycle’s implementation (gamma as the expand/contract clock, the laminar circuit, STDP, SWRs nested in Slow-4). Charitably read, Savitch stands for memoisation and Urysohn for “collapsed, separated classes admit a simple readout”. On that reading the core is a coherent restatement of amortised inference and complementary learning systems, with untested and largely non-discriminating predictions. The headline scaling law, linear cortex giving exponential reach (Theorem 2), is stated without argument, and the claim that collapse defeats the curse of dimensionality leaves the cost of learning the collapse unaddressed. | Read |
| NOTE-330 | Damasio & Carvalho — The nature of feelings | An Opinion with no new data. Feelings are the felt side of interoceptive body maps, and they report homeostatic value. Feeling does not need the insula: the authors’ own patient with both insulae destroyed still feels. It needs the upper brainstem, where whole-body maps first assemble. The evolutionary story (felt maps beat unfelt ones because they support learning and anticipation) and the cellular one (unmyelinated, ligand- and ion-permeable interoceptive axons, with ephaptic coupling, as the root of sentience) are hypotheses, and are presented as such. | Read |
| NOTE-331 | Bechara, Damasio, Tranel & Damasio — Deciding advantageously before knowing the advantageous strategy | Ten controls and six ventromedial prefrontal patients play the four-deck gambling task while anticipatory skin-conductance responses (SCRs) and verbal reports are tracked. Every control and no patient develops anticipatory SCRs; three patients who can state the right strategy still choose badly. Controls prefer the good decks significantly only from the hunch period, and the pre-hunch SCR effect is a group-by-period interaction, not a deck difference, so “before knowing” is better supported for articulated strategy than for any awareness at all. | Read |
| NOTE-332 | Damasio — The somatic marker hypothesis and the possible functions of the prefrontal cortex | The somatic marker hypothesis as its author stated it in 1996. Ventromedial prefrontal cortex stores links between classes of situation and the body states that accompanied them; on recurrence it re-enacts those states, via the body or an “as if” loop, and the re-enacted state marks imagined option-outcome pairs as good or bad, overtly as a feeling or covertly as a bias, pruning the space reasoning must search. The evidence is summarised from earlier lesion and skin-conductance studies, without numbers. The mechanism is argued, not shown, and the paper says it is not a theory of prefrontal cortex as a whole. | Read |
| NOTE-365 | Integrated Information Theory 3.0 | The 2014 restatement of IIT. Five axioms of experience become five postulates about mechanisms in a state, and an experience is identified with the maximally irreducible conceptual structure of a complex. Exclusion is the anti-nesting rule: of all overlapping sets of elements, only the one with locally maximal Φ is conscious, so no subset or superset of a complex is. It is postulated from the axiom that experience has definite borders; Occam’s razor is invoked only for exclusion within a mechanism. Logic-gate examples give minor complexes, a conscious inactive network, a minimally conscious photodiode and a feed-forward zombie. Nothing larger than about a dozen elements is computable. | Read |
| NOTE-367 | Dennett & Kinsbourne — Time and the Observer | The Cartesian Theater is the tacit assumption that some place or moment in the brain makes contents conscious, so that arrival order there fixes experienced order. The Multiple Drafts model replaces it: discriminations are made once, locally, and revised in parallel; temporal order is represented by content, not by the timing of vehicles. Four timing “anomalies” then need no backward projection. At sub-second scales the difference between pre- and post-experiential revision is said to be only verbal. It is a conceptual argument over published data; no experiment is run. | Read |
| NOTE-372 | Self models | Metzinger’s compact statement of the self-model theory of subjectivity. No substantial self exists; there is a self-model, partly conscious (the PSM), used for global control. A phenomenal self exists if and only if the PSM is transparent; a first-person perspective is a transparent model of the intentionality relation. Self-models can be unconscious and artificial, and embodiment comes in three orders. The central claim is stated with a prediction, not argued; the examples are cited. The online text has editing slips and reference gaps. | Read |
| NOTE-377 | Philosophical conceptions of the self: implications for cognitive science | A short review that sets the minimal self (present self-consciousness) against the narrative self (extended in time), splits the minimal self into a sense of ownership and a sense of agency, and ties their dissociation in schizophrenic thought insertion to Frith’s forward comparator model. It reports an embodied minimal self in neonatal imitation and a momentary one in Strawson and in Tani’s robot, and proposes, against Dennett, that the narrative self is the sum of its narratives. Evidence is cited, not shown. | Read |
| NOTE-433 | Impulsive action: emotional impulses and their control | Frijda’s action-readiness theory applied to impulsive action. Automatic appraisal of concern pertinence elicits a state of action readiness, a motive to change a self–object relation, with control precedence. Emotions differ by mode of action readiness. Events draw several appraisals at once, and the resulting states of readiness interact, so impulse control and much emotion regulation are themselves emotional. Purposive impulsive action is grounded neurally in anticipating an action’s sensory effects (PPC, premotor, cerebellum), with frontostriatal circuits for stopping. | Read |
| NOTE-434 | The theory of constructed emotion: an active inference account of interoception and categorization | Barrett’s theory of constructed emotion, stated through predictive coding. The brain runs an allostatic internal model. Its predictions are concepts, initiated in agranular limbic cortex and corrected by prediction error. Interoceptive consequences are felt as affect. An emotion is a categorization by an emotion concept. Degeneracy and population thinking deny emotion categories neural essences. Basic-emotion and causal appraisal theories are rejected; descriptive appraisals are kept as products of categorization. | Read |
| NOTE-445 | The Diffusion Decision Model: Theory and Data for Two-Choice Decision Tasks | The full diffusion model (drift v with across-trial SD η, boundaries 0 and a, starting point z with range s_z, non-decision time Ter with range s_t) fitted by the χ² quantile method. In three dot-motion experiments with 14–17 participants difficulty maps to drift alone, speed–accuracy instructions to boundaries alone, and a 75:25 proportion mainly to starting point; RT distribution shape is invariant across conditions. Drift variability gives slow errors and starting-point variability fast ones. Reviews aging, aphasia and neural-firing applications. | Read |
| NOTE-446 | The Expected Value of Control: An Integrative Theory of Anterior Cingulate Cortex Function | The paper proposes that dACC estimates the expected value of control: probability-weighted payoff of a control signal minus an intrinsic cost rising with its intensity. dACC uses that estimate to specify the identity and intensity of the control signal, which lPFC and subcortical structures (STN, LC) implement. The account unifies conflict monitoring, reward and prediction-error responses, effort costs and the override of defaults. It is a synthesis without a fitted model, and it leaves open how EVC is computed and what the cost function is. | Read |
| NOTE-449 | The Time Course of Perceptual Choice: The Leaky, Competing Accumulator Model | The LCA: dx_i = [ρ_i − k x_i − β Σ_{j≠i} x_j] dt/τ + ξ_i √(dt/τ), with x_i floored at 0. For two choices x₁ − x₂ is an OU process with K = k − β; d′(t) = d_asy (1 − e^{−Kt})/√(1 − e^{−2Kt}) and d_asy = (2v/σ)√(1/K). On new time–accuracy data the OU curve beats diffusion-with-drift-variance in 7 of 9 fits (combined likelihood ratio about 62). Leak versus inhibition predicts recency versus primacy; 2 of 6 participants favoured the end cluster and 2 opposed it. A fixed-accuracy criterion gives Hick’s law in all three models simulated, so it does not discriminate them. | Read |
| NOTE-451 | Hierarchically organized behavior and its neural foundations: A reinforcement learning perspective | The paper introduces hierarchical RL (options) to psychology and neuroscience as a response to RL’s scaling problem. An actor-critic options model learns faster with useful options (doorways in the rooms task) and slower or worse with unhelpful ones (windows; a shortcut ignored). It proposes DLPFC for option identity, DLS for option-specific policies, and OFC for option-specific values and option-level prediction errors. It predicts phasic dopamine at subtask boundaries and a possible neural pseudo-reward. Option discovery is named as the central problem. | Read |
| NOTE-459 | Uncertainty-based competition between prefrontal and dorsolateral striatal systems for behavioral control | Habit and goal-directed action are model-free (cached values) and model-based (tree search) reinforcement learners, arbitrated by which controller’s Bayesian posterior over action value has the lower variance. Over-training shifts control to the cache because tree search accrues computational noise per step. Task complexity and proximity to reward keep the tree in control. It also predicts that incentive learning should become unnecessary when the caching system is lesioned. | Read |
| NOTE-460 | Précis: Being No One | Metzinger’s own sketch of the self-model theory. Six constraints (globality, presentationality, transparency, convolved holism, dynamicity, perspectivalness) build up consciousness; a transparent self-model yields phenomenal selfhood, so “no such things as selves exist in the world”; transparency is graded, inversely proportional to the attentional availability of earlier processing stages. Phenomenal unity is one global functional cluster. The first-person perspective is a model of the intentionality relation, whose iteration gives introspective and social intelligence. A theory statement: no new evidence. | Read |
| NOTE-461 | The Physics of Optimal Decision Making: A Formal Analysis of Models of Performance in Two-Alternative Forced-Choice Tasks | Proves the pure DDM is the continuum limit of the SPRT and so the optimal two-choice decider. The linearised Usher–McClelland model decouples into a difference process, an O-U with λ = w − k, and a stable sum process, so it reduces to the DDM when k = w and both are large; feedforward inhibition does so at u = 1, pooled inhibition with fast inhibitory units, the race model never. The reward-rate-optimal threshold is unique and depends only on the total delay, giving a parameter-free optimal performance curve (peak decision time about 0.2 of the delay at ER about 18%). | Read |
| NOTE-462 | An Accumulator Model for Spontaneous Neural Activity Prior to Self-Initiated Movement | A three-parameter leaky stochastic accumulator, δx = (I − kx)Δt + cξ√Δt, fitted to Libet-task waiting times (k = 0.5, I = 0.11, threshold at the 80th percentile of output), reproduces the readiness potential (r² = 0.96) and the linear mean–SD relation of waiting times (r = 0.9). In a variant with random clicks, fast responders showed a slow negativity before the click (P < 0.005), and fast and slow clicks were spread equally through the trial (P = 0.64). The neural decision to move is placed at the threshold crossing about 150 ms before movement. | Read |
| NOTE-463 | Model-based and model-free Pavlovian reward learning: Revaluation, revision, and revelation | The paper argues that Pavlovian prediction has a model-based form. A cue that predicted disgusting salt was instantly “wanted” in a novel salt appetite, before retasting, with mesolimbic activation. That needs identity-specific prediction revalued by current state, which no model-free cache provides. It proposes “defocusing” of the predicted outcome as a model-based source of apparent habit. It argues dopamine can carry model-based evaluations. A kappa-transformation model fits the data but is described as phenomenological, and no algorithm is offered. | Read |
| NOTE-466 | HDDM: Hierarchical Bayesian Estimation of the Drift-Diffusion Model in Python | HDDM fits the full DDM (v, a, z, t with sv, st, sz) by MCMC in PyMC, with group-level priors such as μ_a ~ Gamma(1.5, 0.75), μ_v ~ N(2, 3), z_j ~ invlogit(N(μ_z, σ_z²)), and the Navarro–Fuss likelihood. A patsy-style regressor lets a parameter vary with a trial covariate. In simulations with 12 subjects and 20–150 trials, hierarchical Bayes had the lowest trimmed recovery error for every parameter and the highest power to detect drift differences and covariate effects, by up to 20% for the latter with larger effects and few trials. | Read |
| NOTE-467 | The Haken–Kelso–Bunz (HKB) model: from matter to movement to mind | Kelso’s retrospective on HKB. The relative-phase equation dφ/dt = −a sin φ − 2b sin 2φ has stable in-phase and anti-phase states for b/a > 1/4 and only in-phase below; with noise the switch is a nonequilibrium phase transition with critical fluctuations and slowing. Symmetry breaking gives metastability (relative coordination); merged with Kuramoto it models groups. The same dynamics is reported within and between people and in brain activity. A first-person account, not a review. | Read |
| NOTE-477 | Bayesian model reduction | The free energy of any model that differs from a fitted one only in its prior is ln E_Q[P̃/P] plus the fitted free energy, with closed forms for Gaussian, Dirichlet, beta, gamma, categorical and multinomial priors. Greedy pruning by this quantity recovers sparse structure in three simulations. Hierarchical models invert as a cascade of reductions. | Read |
| NOTE-485 v2 | An Active Inference Approach to Modeling Structure Learning: Concept Learning as an Example Case | A partially observed MDP with spare hidden-state slots learns new animal concepts without feedback, refines coarse categories into fine ones, and generalises to an unseen animal in one shot. Bayesian model reduction on the learned state prior resets unneeded slots: right in 45–80% of runs for 4–7 true concepts, never for 2–3, and always when the likelihood is given. | Read |
| NOTE-487 | Post hoc Bayesian model selection | Models that differ only in their priors can be scored from one fitted full model: reduced evidence is full evidence times the posterior expectation of the prior ratio. Savage–Dickey is the point-mass case, ARD the continuous one. Under Laplace the reduced free energy is closed-form. Simulations recover a sparse regression (4,096 models) and a three-edge brain network (64 models). | Read |
| NOTE-488 | Conscious birds | Review. Crow NCL neurons track the reported percept, not the stimulus, and NCL is nuclear rather than laminar; the pigeon connectome has the hub-and-module form GNWT requires; avian pallium has recurrent connectivity (RPT); IIT’s markers (PCI, grid-like lattices) are untested in birds. Pigeons and roosters fail the mark test but discriminate their mirror image from a conspecific. GNWT and RPT requirements “seem to be mostly met”; the authors call the evidence short of a strong conclusion. | Read |
| NOTE-489 | Three types of phenomenal consciousness and their functional roles: unfolding the ALARM theory of consciousness | ALARM: basic arousal (level-1 experience, subcortical) alarms the agent when homeostasis fails, triggering survival behaviour, care for the body and generalised learning without choice; general alertness (level-2, cortical, attention-guided) enables flexible learning and decision; reflexive self-consciousness is general alertness plus metacognitive self-relational content, enabling long-term planning. IIT, HOT and GNWT are said to cover only general alertness. Argued, not tested. | Read |
| NOTE-494 | Cross-region neuron co-firing mediated by ripple oscillations | In 35 patients (43 sessions, 1,373 units) doing a Sternberg task, ripple co-occurrence between bundles is about 5% at every distance from 71 to 223 mm, and unit pairs co-fire a median 34% more during co-ripples than in no-ripple periods (n = 31,489 pairs), 117% more by rate-corrected STTC. Load 3 raises co-ripple co-firing 13% (maintenance) and 19% (retrieval) over load 1. Encoding co-firing recurs at retrieval in 0.29% of cell-pair trials in co-ripples versus 0.14% outside them, 0.36% versus 0.23% for fast versus slow load 3 responses. | Read |
| NOTE-495 | What Is Wrong with the No-Report Paradigm and How to Fix It | No-report paradigms separate consciousness from report but not from post-perceptual cognition that tracks the percept (the bored monkey problem), so prefrontal decoding in no-report rivalry does not show that prefrontal cortex is part of conscious perception. A no-differential-post-perceptual-cognition paradigm is needed. Brascamp et al.’s inconspicuous rivalry, whose switches subjects detected at chance, found no prefrontal difference by fMRI, which Block counts as some support for non-cognitive theories while warning fMRI may be too coarse. | Read |
| NOTE-496 | Two neural correlates of consciousness | Proposes a phenomenal NCC (minimal basis of an experience’s content, for seen motion recurrent MT/V5–V1 activity) and an access NCC (frontoparietal workspace broadcasting). Because access is winner-take-all, a recurrent sensory content can lose and go unaccessed. Signal-detection readings of the exclusion task and of Supèr et al.’s V1 figure–ground modulation, which persists when low salience or many catch trials uncouple it from detection, are offered as evidence. | Read |
| NOTE-497 | Consciousness, accessibility, and the mesh between psychology and neuroscience | States the methodological puzzle: the neural basis of phenomenology can be found only by deciding whether it includes the machinery of access, which reports cannot decide. Answers it by inference to the best explanation: in Sperling, Landman et al. (capacity 6–7 of 8 when cued up to 1.5 s after offset, versus 4) and Sligte et al. (up to 32 items, 4 s) phenomenology overflows a working memory of about four. If workspace activation is not part of phenomenology, losing recurrent sensory coalitions explain the overflow. | Read |
| NOTE-498 | Block — Précis of The Border between Seeing and Thinking | Block restates the thesis of his 2023 book, that perception is constitutively iconic, nonconceptual and nonpropositional and cognition paradigmatically discursive, and develops its least explained notion, the cognitive envelope: the global workspace conceptualises percepts, and the representations held in working memory are task-dependent abstractions that differ from perceptual ones in nine documented ways. Iconicity is defined by tracking and mirroring. Infant and animal iconic thinking is conceded but placed inside a cognitive envelope. | Read |
| NOTE-499 | Distinct ventral stream and prefrontal cortex representational dynamics | In 430 visually responsive subdural electrodes from 10 patients, HFA (70–150 Hz) amplitude and category selectivity fell about 80% from peak by 800–900 ms while images stayed on. Ventral temporal decoding stayed near ceiling (face–watch AUC 99.8%), generalised across time, and ended about 230–450 ms after offset at every duration. Prefrontal and parietal decoding (peak AUC 84–86%) was confined to about 150–600 ms and ignored duration. Exemplar geometry was sustained only in ventral temporal cortex. | Read |
| NOTE-500 | Perceptual consciousness overflows cognitive access | Against sparse readings of Sperling and the Amsterdam change-detection tasks, which posit conscious generic or fragmentary representations plus detailed unconscious iconic memory: there is no independent evidence for the latter, and the one direct test of unconscious working memory (Soto et al., just above 55% at 5 s) is too weak. Fragile VSTM holds 7, 6 and 5 of 8 items at 1, 2.5 and 4 s, is cortical, and is spared by inattention and right dlPFC TMS that impair working memory. | Read |
| NOTE-502 | Interacting spiral wave patterns underlie complex brain dynamics | Phase fields of 0.01–0.1 Hz HCP fMRI on the flattened cortex hold about 16 spirals per hemisphere at rest (radius 10.5 ± 4.8 mm), centred on phase singularities that move at 2.2 mm/s with superdiffusive exponent β ≈ 1.5 and sit on functional boundaries. Opposite spirals annihilate (51% fully, 46% partly), like ones repel (2.6%). Spiral centres and charges decode four language conditions at 48.3% (chance 25%, raw-amplitude decoder 30.2%), and spiral pairs act as gates and walls that route task activity flow. | Read |
| NOTE-505 | Comparing the Major Theories of Consciousness | Compares higher-order thought, global workspace and biological theories by whether they can recognise the explanatory gap. HOT and the workspace replace it with puzzles of their own making; only the biological theory fully acknowledges it, and concept dualism (Nagel, Loar) keeps it from implying dualism. Ambitious HOT also suffers ad hoc stipulation, the mismatch problem and implausibility for infants. Goldberg et al.’s data suggest self-related activity is inhibited in intense perception. The biological theory is the least friendly to machine consciousness. | Read |
| NOTE-507 | Damasio & Damasio — Homeostatic feelings and the biology of consciousness | An Essay with no data. Consciousness is the spontaneous identification of mind contents as one’s own, provided by continuous homeostatic feelings that are conscious in themselves and “lend” consciousness to exteroceptive images. Feelings are hybrid because interoceptive pathways (unmyelinated, partly non-synaptic, barrier-free) let the body act on its own map. Evidence is cited clinical contrast: posterior brainstem lesions cause coma, extensive cortical lesions may not; anaesthetics act at membrane-level sensing below feeling. | Skimmed |
| NOTE-510 | Mashour, Roelfsema, Changeux & Dehaene — Conscious Processing and the Global Neuronal Workspace Hypothesis | A proponents’ review. Conscious access is ignition: a sudden, self- sustaining, all-or-none activation of long-range hub neurons (prefrontal among them) that broadcasts one representation, against a decaying wave for unseen stimuli. Its best evidence is van Vugt et al.’s monkey recordings, where the signal-detection threshold is the prefrontal ignition threshold, plus a late (>200 ms) seen/unseen divergence across modalities and drug-invariant frontal-parietal disconnection under anaesthesia. It is a theory of access; it calls phenomenality without access untested, and admits the main theories cannot yet be told apart. | Read |
| NOTE-549 | Rarely categorical, highly separable representations along the cortical hierarchy | Within single regions of mouse cortex during the IBL task, neurons’ 8-variable selectivity profiles are more clustered than a covariance- matched Gaussian only in VISp, AUDp and SSp-ul, while pooled modules and the whole cortex cluster along anatomical lines. Over the conditions each region distinguishes (M_IC 5–16), ≥ 95% of random balanced dichotomies are decodable above a shuffle null in 15 of 16 regions (GU 0.82). Clustered neurons provably cap the condition geometry’s participation ratio near min(k, M). | Read |
| NOTE-668 | Hippocampal spatial representations exhibit a hyperbolic geometry | In rat dorsal CA1, the rank order of pairwise spike correlations matches points drawn uniformly from a 3D hyperbolic ball, not from a low-dimensional Euclidean cube, and the ball’s radius grows with the logarithm of exploration time. Place-field sizes are near exponential, which a Poisson model shows is more informative than uniform or log-normal sizes. The evidence separates “hyperbolic ball, uniform” from “Euclidean cube, uniform”; it does not separate a hyperbolic metric from an exponential distribution of field sizes, and the hierarchy it describes is nesting of field scales, not a recovered tree. | Read |
| NOTE-670 | An argument for hyperbolic geometry in neural circuits | A perspective, not a result: hyperbolic geometry should suit neural circuits because it approximates trees, makes networks navigable, and shares with Zipf’s law an exponential growth of states. The Zipf link is an analogy that any power-law rank distribution, and any system with extensive entropy, would satisfy; the case for three dimensions leans on Mostow rigidity, which does not bear on noisy embeddings; and the only data shown are the olfactory embedding of Zhou, Smith & Sharpee (2018). | Read |
| NOTE-672 | Hyperbolic geometry of the olfactory space | In four natural odour sources, rank-ordered concentration correlations match points near the surface of a 3D hyperbolic ball and not uniform Euclidean cubes; human odour-descriptor profiles match a full 3D hyperbolic ball. The evidence separates “hyperbolic shell” from “uniform Euclidean cube” only. On a thin shell, hyperbolic distance is nearly a monotone function of angle, so a sphere in flat space, which was not tested, would be a close rival, and the hierarchy that motivates the model is not recovered from the data. | Read |
| NOTE-753 v2 | Harvey, Larsen & Williams — Duality of Bures and Shape Distances | For centred linear kernels K_X = CXXᵀC, the Bures distance equals the Procrustes distance, B(K_X, K_Y) = P(X, Y), and normalized Bures similarity equals the cosine of the Riemannian shape distance. Both follow from F(K_X, K_Y) = ‖XᵀCY‖_*. By Uhlmann’s theorem, the fidelity is the largest overlap between representations consistent with the two kernels. CKA is only loosely tied to NBS, inside a rank-dependent envelope. The result is finite-dimensional and linear; the infinite limits are heuristic. | Read |
| NOTE-761 | Theriault et al. — Allostasis at the core of brain function | A review arguing that the brain’s core function is allostasis, the predictive regulation of the body. Its evidence is an intrinsic allostatic system of visceromotor and interoceptive regions that matches tract-tracing and contains the default-mode and salience hubs; a limbic-to-sensory cytoarchitectural gradient read as a prediction hierarchy; and interoceptive effects on brain-wide signalling. It proposes that cognitive decline in Alzheimer’s disease may be an allostatic trade-off. The authors say they do not claim the hypothesis is correct. | Read |
| NOTE-766 | Linson et al. — Impaired context disambiguation in post-traumatic psychopathology | An active-inference model of PTSD as lost context disambiguation. An overly precise prior that one is in a harmful context makes the exploratory policy look uninformative. The agent attenuates its periphery, never gets the evidence that would correct the prior, and the belief sustains itself. Shown only in illustrative simulations, which also contrast exposure that restores context sensitivity with a precision-lowering drug that removes symptoms until it stops. | Read |
| NOTE-767 | Tononi, Sporns & Edelman — A measure for brain complexity | Defines neural complexity C_N as the summed shortfall of average subset integration below a linear increase with subset size, equivalently the average mutual information across bipartitions summed over sizes. It is zero for independent parts, low for uniformly dependent ones and high when the two coexist. In simulated cortex, patchy grouped connectivity gives higher C_N than the same connections spread randomly. One number for a whole system, with no partition, threshold or penalty. | Read |
| NOTE-779 | Kanerva — Sparse Distributed Memory and Related Models | SDM is a two-layer memory: a fixed random address matrix selects a few of many hard locations near the cue, and an outer-product contents matrix stores the word there. Recall of uniform random data has signal pM against noise pM[1 + pT(1 + p²M)], best at p = (2MT)^−1/3, and capacity tends to 1/[Φ⁻¹(φ)]² of the hard locations, about 0.1 at fidelity 0.999. An ordinary RAM is the special case of radius zero. | Read |
| NOTE-797 | Mashour & Alkire — Evolution of consciousness and emergence from anesthesia | A colloquium perspective, not a study. It proposes emergence from general anaesthesia as a model of the evolution of consciousness, and, from one PET study in which the return of a response to command correlated mainly with brainstem, thalamus, hypothalamus and anterior cingulate, infers that early mammals and birds are phenomenally conscious. The return is judged by an access marker, which the authors concede, and the transfer to other species is by anatomical homology. | Read |
| NOTE-799 v2 | Luppi et al. — A synergistic workspace for human consciousness | In resting-state fMRI, regions where synergistic interactions outrank redundant ones form a “synergistic workspace”. Within it, regions whose synergistic connections spread across more resting-state networks than their redundant ones are classed as gateways (mainly default mode), and the rest as broadcasters (mainly fronto-parietal, lateral prefrontal above all). Pairwise integrated information ΦR falls between DMN gateway regions under propofol (n = 15 or 16; the paper gives both) and in 22 patients with disorders of consciousness against controls, and recovers after anaesthesia, while the original whole-minus-sum Φ shows no common decrease. The increases, near the broadcasters, are not robust. | Read |
| NOTE-812 | Cogitate Consortium — Adversarial testing of GNWT and IIT | A preregistered adversarial test of IIT and GNWT in 256 people (fMRI, MEG, iEEG) viewing clearly seen images. Category, identity and orientation were decodable in posterior cortex; prefrontal cortex held category, no identity, and orientation only weakly in MEG. No prefrontal site showed the predicted offset ignition. Sustained gamma synchronization within posterior cortex, IIT’s distinctive prediction, was not found. Each theory passed some predictions and failed others. | Read |
| NOTE-818 | Gidon, Aru and Larkum — Does neural computation feel like something? | A five-neuron NEURON simulation shows that a voltage clamp replaying a recorded response injects no current when the matching stimulus is shown, yet fixes every state transition whatever the input. Under computational functionalism, which counts the transitions that did not happen, the clamp changes the computation and so the experience while changing no activity and no actual causal interaction. The authors read this as a challenge to functionalism, not a refutation. | Read |
| NOTE-819 | Hopfield — Neural networks and physical systems with emergent collective computational abilities | With symmetric couplings, asynchronous threshold updates descend an energy function, so Hebbian outer-product storage makes random patterns attractors: a cue a few bits off settles into the nearest one. In simulations at N = 30 and 100, recall degrades severely near 0.15N patterns, memories closer than about a tenth of N fuse, and overload makes every memory irretrievable unless old ones are forgotten. | Read |
| NOTE-827 | Haggard — Sense of agency in the human brain | A review of the sense of agency as the experience of instrumental control over a specific motor act and its outcome. Implicit measures (intentional binding, interval estimates) show a prospective component from action selection and outcome prediction alongside the retrospective one the comparator model gives, and psychosis seems to remove the prospective part. Frontal–parietal connectivity, not a single comparator site, is proposed as its correlate. Coercive instruction reduces it. | Read |
| NOTE-834 | Harvey, Lipshutz & Williams — What Representational Similarity Measures Imply about Decodable Information | For a linear readout that maximizes zᵀXw/M − ½wᵀG(X)w, the decoded signal is K_X z with K_X = XG(X)⁻¹Xᵀ/M, so the task-averaged agreement of two representations is Tr(K_X K_z K_Y). With K_z = I that is linear CKA, mean squared CCA, ENSD or the GULP distance, for particular G. Procrustes distance and average decoding distance bound each other only through the participation ratio of K_X − K_Y. The population limit (App. A.3) is an outline that requires b > 0 and a trace-class task covariance, and it does not reach the K_z = I case. | Read |
| NOTE-849 | Seth & Bayne — Theories of consciousness | A review of four families: higher-order, global workspace, integrated information, and reentry and predictive processing theories. Each is sorted by which aspect it explains (global states, local contents, phenomenal character, function), its anatomical commitment, and its evidence. The front-versus-back dispute is at heart a dispute over consciousness and cognitive access. Posterior-sufficiency predictions cannot now be tested because verification relies on report, which needs anterior activity, and no marker of consciousness has a validation that rests neither on introspection nor on a contested theory. | Read |
| NOTE-858 | McAllister & McCrea — Long-term consequences of repetitive concussion | A narrative review: almost all athletes recover clinically within 1–2 weeks of a sport concussion, but when it was written (published March 2017) no prospective longitudinal study had measured the long-term cognitive, psychiatric or neurodegenerative risk of repeated concussion or of non-concussive head impacts. The evidence for such risk, CTE included, is retrospective, case-based or survey-based and mixed, and the authors call for large prospective cohorts with controls. | Read |
| NOTE-870 | Geisler — Contributions of ideal observer theory to vision research | A short review, not a methods paper. It defines the ideal observer as the device that “performs a given task at the optimal level possible, given the available information and any specified constraints”, writes the Bayesian ideal as an argmax of expected utility over the posterior given either the stimulus S or a constrained neural representation Z = g(S;θ) (eq. 1), and surveys applications from photon-noise detection to eye-movement search. It gives no formula for efficiency and no procedure for locating information loss beyond saying that constraints are added to the ideal one at a time (optics, receptor sampling, receptor noise, ganglion-cell summation) and that models are built by “degrading the ideal observer with hypothesized neural noise or with hypothesized heuristic computations”. Its constraints restrict the information available to an optimal decoder; it has no notion of an optimum over a restricted class of computations, though its attention examples compare the ideal with specific suboptimal rules (a one-location “serial” mechanism, a MAP searcher, a random searcher). | Read |
| NOTE-883 | Ballard, Hayhoe, Pook & Rao — Deictic codes for the embodiment of cognition | At about a third of a second, the time scale of a saccade, the article models fixation as a pointer that binds a variable in a behavioural program to a place in the world, so that what is bound is only the task-relevant feature, fetched just before use. In a block-copying task subjects looked back at the model about 1.3 times per block on average, the commonest cycle being two looks per block (one apparently for colour, one for position), and chose this slowest, lowest-memory strategy (about 3 s a block, against about 1.5 s for copying from memory) though told to be fast; separating model and copy by 70° cut looks to 1.0 per block, and one-colour patterns that could be chunked cut them to 0.7. The authors read this as working memory having a “carrying cost” that exceeds the cost of re-acquiring from the world, but that cost is inferred from the choices and never measured or modelled, and the evidence is one task with small samples (seven subjects for the main data, three for the colour-change experiment) and no statistics reported in the article. What is left in the world is unprocessed input, not a computed result, and the article argues against precomputation where the needed products cannot be foreseen. | Read |
| NOTE-947 | Giarrocco & Averbeck — sensory and choice information flow between A1 and PFC | In 37 sessions of simultaneous recordings from A1 and dorsolateral PFC of two macaques reporting by bar release whether two tones came from the same side, cue-side information flowed A1 to PFC only (onset 120–147 ms), while choice information (release or hold) flowed first PFC to A1 (onset 315–365 ms after target) and then A1 to PFC (352–419 ms), both peaking near 500 ms, close to the bar release. The flow measure is a lagged regression on one-dimensional projections, so the result is correlational, within a trial, and does not separate the decision from the motor response. | Read |
| NOTE-948 | Kübler & Birbaumer — BCI and extinction of goal-directed thinking in CLIS | Of 35 patients trained with EEG BCIs in Tübingen, degree of paralysis explained BCI performance (η² = .40) only because of the seven in the completely locked-in state, none of whom reached the 70% needed for yes/no communication; without them the relation vanished (η² = .12, n.s.). All seven were already in CLIS when training began. The authors propose, by analogy with the curarized rat, that lost perception of the contingency between a response and its consequences extinguishes goal-directed thinking, while “passive sensory information processing is intact”, and predict that a contingency learned before CLIS and carried into it should prevent extinction. | Read |
| NOTE-950 | Ma & Kragel — map-like emotion knowledge in hippocampus and vmPFC | In fMRI of 29 people passively watching 14 emotional films, decoders trained on hippocampal patterns predicted an independent sample’s consensus ratings of 13 emotion categories better than positions in a two-dimensional affective space, and vmPFC showed the reverse; patterns could also be decoded into the activity of a Tolman–Eichenbaum Machine that had learned a grid built from rating correlations by random walk, hippocampus favouring its small-scale conjunctive layer and vmPFC its large-scale structural layer. Effects are small (prediction–outcome correlations of about 0.04–0.10), and no learning in the participants was measured. | Read |
| NOTE-951 | Chaudhary et al. — intracortical spelling in a completely locked-in patient | A man with ALS (born 1985), who had used an eye-movement BCI with an auditory speller until February 2019 and was judged completely locked-in from a few weeks before implantation in March 2019, was given two 64- channel arrays in left motor cortex. Attempted and imagined movements gave no usable signal; from day 86 he was given auditory feedback of firing rate, matched target tones from day 98, and from day 106 spelled with the same speller he had used before CLIS. Over days 106–462 he produced intelligible text on 44 of 107 days on which spelling was attempted, at about 1 character per minute. | Read |
| NOTE-953 | Sung, Rigotti & Lee — factorized goal and uncertainty codes in lateral PFC | A reanalysis of 20 people’s fMRI from a 2014 two-stage Markov task with cued goals and block-wise transition noise. Goals and transition uncertainty are linearly decodable, weakly, from vlPFC, dlPFC and OFC, in a geometry whose nonlinear dichotomies decode worse than goal and linear ones (“factorized”), and a goal decoder trained under one noise level transfers to the other. Goal separability and transfer in lateral PFC correlate with choice flexibility and optimality across subjects; uncertainty separability does not. Unfitted model-free agents show a flexibility–stability trade-off that model-based agents and humans do not. | Read |
| NOTE-956 | Parr & Friston — attention or salience? | A short review that separates two things called attention: gain control, which weights currently available sensory data by their estimated precision, and salience, the expected information gain of an action (typically a saccade) that would acquire new data. It then ties them together: a saccade is driven by a prediction that a location will be sensed with high precision, so covert attention to a place biases an overt saccade there, which the authors read as support for the premotor theory. | Read |
| NOTE-958 | Sandved-Smith et al. — computational phenomenology of mental action | A three-level discrete active-inference model in which attentional states set the precision of the perceptual likelihood and meta-awareness states set the precision of the attentional likelihood; mental action is a choice of ‘stay’ or ‘switch’ over attentional states, defined at the second level only, against a preference to observe oneself ‘focused’. Simulations reproduce the cycle of focus, mind-wandering, noticing and refocusing, with longer mind-wandering under low meta-awareness. The stimuli are fixed by the generative process, so mental action changes only how strongly they update belief; the likelihoods themselves are not learned. | Read |
| NOTE-960 | Friston et al. — action and behavior: a free-energy formulation | Existence is taken to require a low-entropy ensemble density; an ergodic assumption turns that entropy into time-averaged surprise, and because the setup stipulates that action is the only way an agent changes the hidden states it senses, action as well as perception must minimize a free-energy bound on surprise. Action enters nowhere in the generative model: it is a gradient descent that fulfils proprioceptive and visual predictions, and in simulations of eye, arm, mountain-car and Lorenz movements it cancels unexpected perturbations so they are not perceived. The paper fixes the model and re-samples the data, and answers the worry that this confirms a wrong model by appeal to existence: agents without the right priors cannot exist. | Read |
| NOTE-961 | Bruno et al. — self-assessed well-being in chronic locked-in syndrome | Of 168 members of the French LIS association invited, 91 answered and 65 gave usable ratings: 47 (72%) rated their present life at or above the midpoint between their best period before LIS and their worst period ever (median +3), 18 (28%) below (median −4). Happiness was associated with longer time in LIS (OR 1.5 per year), recovered speech (OR 20.5) and absence of anxiety (OR 0.19). All had chronic LIS after a brainstem vascular accident, a median of 8 years earlier; 55% had recovered some speech and 70% some limb movement, and answers were given with a proxy’s help. | Read |
| NOTE-962 | Owen et al. — detecting awareness in the vegetative state | A 23-year-old woman who met the clinical criteria for the vegetative state five months after a traumatic brain injury, told in the scanner to imagine playing tennis or walking through her house, activated the supplementary motor area for the first and parahippocampal, posterior parietal and lateral premotor cortex for the second, as 12 healthy volunteers did. The authors take her compliance as “a clear act of intention” that “confirmed beyond any doubt” her awareness. No question was asked or answered. | Read |
| NOTE-964 | Monti et al. — willful modulation of brain activity in disorders of consciousness | Of 54 patients diagnosed vegetative (23) or minimally conscious (31), 5, all with traumatic injury, produced task-specific fMRI activity to motor and spatial imagery commands; 4 had been admitted as vegetative, and 2 of those showed no behavioural sign of awareness at the bedside even after the scans were known. One patient, Patient 23, answered five of six autobiographical yes/no questions correctly by choosing which imagery to perform, the investigators scoring blind; the sixth gave no signal. He was not one of the two behaviourally unresponsive patients: retesting found inconsistent signs of a minimally conscious state, but no bedside communication. | Read |
| NOTE-971 | Wiskott and Sejnowski — Slow feature analysis | Finds instantaneous functions y = g(x(t)) whose outputs vary as slowly as possible, minimizing ⟨ẏ²⟩ under zero mean, unit variance and decorrelation. Over a fixed nonlinear expansion (all monomials of degree one and two), the problem is solved in closed form by sphering and then taking the smallest eigenvectors of the derivative covariance, a generalized eigenproblem. Stacked modules learn translation, size, rotation, contrast and, less well, illumination invariance for 1-D patterns, depending only on the training stimulus. The closed form is proved; everything about invariance, generalization and hierarchy is demonstrated on synthetic signals. The premise that slower means more abstract is assumed, not shown, and no generative model is used. | Read |
| NOTE-991 | Apps & Tsakiris — The free-energy self | A free-energy account of self-recognition and body ownership. One’s own body, face and voice are represented probabilistically as “me” by a high-level multimodal prior learned from cross-modal correlations, and the self is “the most parsimonious and accurate explanation for sensory inputs”. The rubber hand, enfacement and rubber-voice illusions are one effect: synchronous stimulation leaves unimodal surprise that multimodal areas explain away by shifting probability from one’s own body part to the other’s. Context acts as a prior. No brain area is self-specific. The authors grant there is little direct evidence and that the account is hard to falsify with standard fMRI. | Read |
| NOTE-992 | Abdulkarim & Ehrsson — No causal link between hand position sense and limb ownership | A motor slid the hidden hand 8 cm toward or away from the rubber hand during brushing, too slowly to be noticed. Pointing followed it by about 5–6 cm, but questionnaire ownership depended only on synchrony and not on where the hand was moved, in two experiments of 18. With the hand still, the classic synchronous drift and its correlation with the illusion reappeared. The authors conclude drift is not a cause of ownership; the null is from small samples within the illusion’s known spatial range. | Read |
| NOTE-993 | Kalckert & Ehrsson — Moving a rubber hand that feels like your own | A moving rubber hand illusion in which the participant’s hidden finger moves a model finger by a rod. Synchrony gave ownership, agency and drift toward the model; asynchrony removed all three. Passive movement removed agency and kept ownership and drift; a model hand rotated 180° removed ownership and drift and kept agency. The double dissociation is on questionnaires; agency was stronger, and tied to ownership, only when the hand was owned. | Read |
| NOTE-997 | Ehrsson et al. — No specific relationship between hypnotic suggestibility and the rubber hand illusion | A reanalysis of Lush et al.’s (2020) open data, n = 353. The synchronous-minus-asynchronous difference in rubber-hand illusion ratings is unrelated to hypnotisability (rho = -0.066, BF01 = 5.7), is significant in every hypnotisability quartile, and is not changed by explicit suggestions about which condition should work; the hypnotisability correlations Lush et al. report appear equally for the asynchronous condition and an “impossible” control item. The authors conclude the illusion is a perceptual one, “driven primarily by multisensory mechanisms”. The reply grants every number and disputes that the asynchronous condition controls for expectation. | Read |
| NOTE-998 | Hohwy & Paton — Explaining away the body | With a foreign arm seen exactly where one’s own arm lies, synchronous tapping raised ratings that the felt touch was produced on the seen arm, and after onset also that a finger hovering 5 cm away caused it or that it was caused on a cardboard box; the box gave no synchrony difference without prior onset. Samples of 9 to 13, single leading questions, no ownership item, no expectation measure, and a 0.13 °C cooling of the real hand in one comparison of four, significant only one-tailed. | Read |
| NOTE-999 | Lenggenhager, Tadi, Metzinger & Blanke — Video ergo sum | In video virtual reality, synchronous stroking of one’s back and of a body seen 2 m ahead made people rate that body as theirs and shift their felt self-location about 17–25 cm toward it, in two samples of 14; a mannequin worked, a box mostly did not. Nobody felt disembodied or saw from elsewhere, so the authors claim a partial, heautoscopy-like state, not an out-of-body experience. The effects are modest and partly inconsistent, and critics argued they may be self-recognition in a video system rather than an illusion of ownership. | Read |
| NOTE-1000 | Seth — Interoceptive inference, emotion, and the embodied self | An opinion article that extends predictive coding to interoception. Felt emotion is the content of hierarchical top-down predictions of the causes of interoceptive signals. Prediction errors are registered in the anterior insula, and are also cancelled by autonomic action under attenuated precision. The experience of body ownership is the same inference run over interoceptive and exteroceptive signals together. The evidence is indirect and cited: insula anticipation and error responses, false cardiac feedback, interoceptive sensitivity predicting rubber-hand susceptibility, and a heartbeat-synchronous virtual hand owned more. No direct test is claimed. | Read |
| NOTE-1002 | Blanke & Metzinger — Full-body illusions and minimal phenomenal selfhood | Names minimal phenomenal selfhood (MPS), the simplest experience of being a self, and gives it three dimensions: global self-identification with the body, self-location, and a weak, geometrical first-person perspective. Part ownership (rubber hand, somatoparaphrenia) does not reach MPS; out-of-body experience, heautoscopy and full-body illusions do, varying it dimension by dimension. A passive multisensory sense of owning the whole body suffices, so agency is causally enabling but not constitutive. The necessity and sufficiency claims are asserted, not shown. | Read |
| NOTE-1003 | Lush & Seth — Reply to: No specific relationship between hypnotic suggestibility and the rubber hand illusion | The reply to Ehrsson et al. accepts their reanalyses and denies their reading: expectancies are higher for synchronous than asynchronous brushing, the difference does not vary with hypnotisability (b = -0.16, P = 0.072, B = 0.07), so a null relation between hypnotisability and the synchrony effect is what demand characteristics predict. Agreement with the ownership item rises with hypnotisability (b = 0.76 per SWASH point, rs = 0.27) and reaches minimal agreement only in the top 31%. Whether multisensory integration matters to RHI measures awaits experiments that control expectation. It shows that the suggestion control THEORY-765 accepts can be met without the confound being removed. | Read |
| NOTE-1004 | Longo et al. — What is embodiment? A psychometric approach | 131 people rated 27 statements after synchronous and asynchronous brushing of a rubber hand. Principal components analysis found embodiment of the rubber hand, loss of own hand, movement and affect in both conditions and deafference after asynchrony only; embodiment split into ownership, location and agency. Ownership and location crossed from negative to positive with synchrony and each predicted proprioceptive drift (1.34 cm against 0.30 cm); agency stayed negative. No control separates any of it from expectation. | Read |
| NOTE-1006 | Botvinick & Cohen — Rubber hands ‘feel’ touch that eyes see | The founding report of the rubber hand illusion. Synchronous brushing of a seen rubber hand and the hidden real hand made ten subjects feel the touch at the rubber hand and feel it as their own; after 30 minutes, blind reaches drifted toward the rubber hand in proportion to how long the illusion lasted, and asynchronous brushing removed both effects. The authors read it as constraint satisfaction among vision, touch and proprioception, and conclude that intermodal matching “can be sufficient for self-attribution”. | Read |
| NOTE-1009 | Rohde, Di Luca & Ernst — Feeling of ownership and proprioceptive drift do not go hand in hand | With robot stroking and a visual probe of felt finger position, drift toward a rubber hand was as large when the hand was only seen as under synchronous stroking (about 6 cm), and as large under asynchronous stroking interrupted every 10 s; only continuous asynchrony kept it near zero. Ownership by questionnaire needed synchrony. The authors conclude that drift is visuo-proprioceptive integration that asynchrony suppresses, separate from ownership, and not a proxy for it. Groups of ten; the vision-only ownership report is anecdotal. | Read |
| NOTE-1058 | Chandia-Jorquera et al. — Neurophenomenological signatures of pure awareness in Transcendental Meditation | Thirty-three experienced Transcendental Meditation practitioners and 33 age- and sex-matched controls who counted instead. Drawn retrospectively, the practitioners’ traces of “pure awareness” were higher and more variable than the controls’ (d = 0.77 and 1.32). A random-forest classifier separated meditation from counting at 65% balanced accuracy, chiefly on permutation entropy and aperiodic EEG, and meditation from the practitioners’ own rest at 88%, chiefly on low-frequency phase coherence. No EEG feature was shown to track the reports. | Read |
| NOTE-1060 v2 | Lyre — Neurophenomenal structuralism | A programmatic paper. Its two assumptions: any phenomenal experience is fully individuated, in its specificity, by its place in a quality space (Q-structure), and Q-structure is mirrored in neural structure by a surjective homomorphism from neural maps. From these, with metaphysically necessary supervenience assumed and not argued for, it draws reductive physicalism, an instrumentalist structural representationalism, holism about experience, and the denial that spectrum inversion is nomologically possible. It addresses specific, not generic, consciousness, and says it is not a structural realism. No new data. | Read |
| NOTE-1061 | Bo et al. — Deconstructing the brain bases of emotion regulation | Two fMRI samples (n = 182 and 176) looked at, or reappraised, aversive pictures. Bayes factors for and against each of two contrasts sort voxels into four systems: regions engaged only by reappraisal (anterior prefrontal, temporo-parietal, cerebellar), regions engaged by both negative emotion and reappraisal (most of the reappraisal network), regions engaged by negative pictures and unchanged by reappraisal (all subcortical ones, amygdala and PAG included, with much of cortex), and posterior cortical regions reduced by it. Reported negative affect fell under reappraisal (d = 0.92). Activity is measured; experience is reported once per trial. | Read |
| NOTE-1062 | Whyte et al. — On the minimal theory of consciousness implicit in active inference | A review of active inference simulations of conscious content, self and state, which argues that they share a three-part “hard core”: the imperative to minimise variational and expected free energy; conscious contents as the inferred hidden states of world, body or brain; and conscious access at the interface where continuous sensory beliefs become discrete beliefs that can inform counterfactual policy selection. The third part is an inference to the best explanation, and it is a criterion for which contents are conscious in humans, not for which systems have experience. Two close-to-core predictions are named. New in the paper: a re-run rivalry model that fits Levelt’s laws, a predicted reward violation of them, and a sleep model that loses its P3b-like response. | Read |
| NOTE-1063 v2 | Laukkonen, Friston & Chandaria — A beautiful loop | A conceptual theory that consciousness needs three things in an active-inference system: a unified generative model of the world (an epistemic field); competition to enter it that coherent, precise inferences win (Bayesian binding); and epistemic depth, the recursive sharing of that model back through the hierarchy, formalised as a hyper-model that predicts precision at every level. Awareness is graded by epistemic depth, not by content. It is applied to attention, sleep and lucidity, meditation, cessation and psychedelics, and to AI. There are no data and no simulations, and the formal part is a standard hierarchical model with layer-wise precision hyperparameters. | Read |
| NOTE-1064 | Luppi — Convergent controllers of information integration and its anaesthetic breakdown | Pairwise integrated information ΦR, computed from resting-state fMRI by integrated information decomposition, falls under anaesthesia in humans (sevoflurane), macaques, marmosets and mice, with one mouse regimen the exception, and returns on recovery: spontaneously in humans, and under central thalamic stimulation in two macaques. Network control energy rises with it. Regional loss follows cortical PVALB expression in three species, and species-specific models reproduce both the PVALB effect and the advantage of central over ventrolateral thalamic stimulation. The state measured is behavioural responsiveness, which the authors call “presumably consciousness”. | Read |
| NOTE-1066 | Carruthers & Gennaro — Higher-Order Theories of Consciousness (SEP) | A survey of the theories that make a mental state conscious by its being the object of a higher-order representation: inner sense, actualist and dispositionalist higher-order thought, and self-representational and hybrid views. It sets out the objections (targetless states, the rock, animals, sufficiency) and the prefrontal evidence, and concludes no verdict. Since 2020 it is maintained by Gennaro, a higher-order theorist. Carruthers and Lycan, two of the theories’ main sources, are reported to have given them up. | Read |
| NOTE-1067 | Barrett et al. — The theory of constructed emotion: more than a feeling | A reply by the theory’s architects to van Heijst et al., who gave basic emotion theory the emotion (a bioregulatory state) and constructed emotion the feeling (its representation). The reply says the split is a premise of basic emotion theory, not a division of labour: on constructed emotion the same allostatic signals that regulate the body make feeling, and an instance of emotion is one whole-brain event. It adds evidence lists for structured variation, an evolutionary frame from the extended synthesis, and the thesis that the two theories are incommensurable. No data. | Read |
| NOTE-1084 | Zacks et al. — Event perception: a mind-brain perspective | States event segmentation theory: perception continuously predicts what comes next; a transient rise in prediction error opens a gate that resets working-memory event models and lets sensory input in, and that moment is perceived as an event boundary. Supported by unitization, memory, narrative and imaging studies, mostly correlational and largely from the authors’ groups. Its one acknowledged misfit: the anterior cingulate does not respond at boundaries during passive viewing. It is about watching events, not one’s own intentions, and does not mention doorways. | Read |
| NOTE-1101 | The current status of research on the structure of evaluative space | The evaluative space model restated by its authors. Positivity and negativity are separable systems whose combined output is a bipolar approach–avoid predisposition. They can be activated reciprocally, independently or together. Coactivation is ambivalence, which is rare, arousing and behaviourally indeterminate, and gives the same net output as neutrality. Negativity has the higher gain and positivity the higher intercept, and both recalibrate with context. Evaluation is heterarchical, with higher levels able to override lower. | Read |
| NOTE-1103 | An Appraisal-Driven Componential Approach to the Emotional Brain | A programme for taking the component process model into the brain: five functionally defined networks, appraisal driving changes and synchronization in the other four, synchronization proposed to be neuronal phase or cross-frequency coupling, and feeling emerging when the degree of synchronization passes a threshold. It states that some action tendencies take priority by control precedence. It gives no measure of synchronization, signed or unsigned, per episode or otherwise. | Read |
| NOTE-1107 | Brain networks subserving functional core processes of emotions identified with componential modeling | fMRI during 40 films, with each of 119 short events rated on 32 CoreGRID features. PLSC gives six brain–behaviour processes: valuation, novelty, hedonic impact, goal monitoring, caring for others and approach/avoidance. Valence splits into a wanting-like valuation network carrying the action tendencies and a liking-like hedonic network carrying feeling and expression, and no arousal process appears. There is no synchronization measure, but every event gets a signed score on each process. | Read |
| NOTE-1109 | Berridge and Robinson — Liking, wanting, and the incentive-sensitization theory of addiction | An invited review of the incentive-sensitization theory by its authors. ‘Wanting’ and ‘liking’ have dissociable brain systems. Drugs can sensitize the ‘wanting’ system so that it is lastingly hyper-reactive to drug cues and contexts while ‘liking’ stays flat or falls. Sensitized ‘wanting’ can oppose cognitive desire, run without report, and grow in abstinence, and the theory is being extended, on weak evidence, to behavioural addictions. For the record it is a mechanism for proxy-keyed potential in persons. It also shows that the addict case CLAIM-433 settles holds only if the sign of valence is read along the proxy. | Read |
| NOTE-1110 | Berridge and Kringelbach — Pleasure systems in the brain | A review. Reward splits into ‘liking’, ‘wanting’ and learning. ‘Liking’ is measured without report by taste reactivity, homologous across species, and is generated by small opioid hotspots. Dopamine and most “pleasure electrodes” raise ‘wanting’ and leave ‘liking’ alone, and sensitized ‘wanting’ can grow while the drug becomes less pleasant. Objective ‘liking’ can occur without felt pleasure. For the record, this is the sharpest test so far of “valence is potential”. Read as written, the identity fails, and the dissociation calls for a hedonic marker measured apart from control. | Read |
| NOTE-1115 | Conscious emotional experience emerges as a function of multilevel, appraisal-driven response synchronization | A theoretical paper with a short review of EEG and neural-synchrony evidence. Conscious emotional experience is recruited when lower, automatic levels of appraisal and regulation fail, which happens when component synchronization is strong and lasting. Conscious regulation needs explicit representations. The feeling is a central representation of the components and their coherence, built by local and distant neuronal synchronization. Proposed measures are EEG band activity in felt versus unfelt episodes, and phase coherence between regions. | Read |
| NOTE-1119 | Bridging emotion theory and neurobiology through dynamic systems modeling | A dynamic-systems model of appraisal and emotion. Their constituents organize one another through feedback and circular causality into one emotional interpretation (EI): triggered by a perturbation, self-amplifying until it takes over the system, then self-stabilizing as competing cues are resolved. EIs are attractors, one at a time, with abrupt transitions between them. Vertical integration gives them momentum and selects among them. Stable EIs drive learning, so real-time and developmental order are interdependent. Predicts theta-band phase synchrony as an index of emotional relevance. | Read |
| NOTE-1130 | Gerstner et al. — Eligibility traces and plasticity on behavioral time scales | A review by theoreticians. In a three-factor rule, pre- and postsynaptic co-activation sets a decaying synaptic flag, the eligibility trace, and the weight changes only if a third signal (reward minus expected reward, surprise, novelty, or a neuron-specific error) arrives while it is set. Five experimental papers (2014–2017), mostly in slices, give traces of about 1 s in striatum, 3–10 s in cortex, about 2 s and about a minute in hippocampus. The authors grant that other mechanisms could bridge the same gap. | Read |
| NOTE-1138 | Friston et al. — Active inference and learning | A discrete-state active inference scheme in which a habit is one more policy, a state-to-state transition model learned by counting observed transitions, and the prior over policies is learned by counting which policies were pursued. In simulated T-maze foraging the agent first explores, then exploits, then acquires a habit; after the habit is acquired it persists when the reward is devalued, and before it is acquired behaviour switches at once. Simulations only; the authors say the scheme makes probably no new behavioural predictions. | Read |
| NOTE-1249 | Retention of Memory through Metamorphosis: Can a Moth Remember What It Learned As a Caterpillar? | Tobacco hornworm caterpillars trained to pair ethyl acetate with mild shock avoided it as fifth instars (78%, N = 41) and, four to five weeks and a metamorphosis later, as moths (77%, N = 27); 80% of tracked individuals chose the same way at both stages. Controls showed no effect. Washing trained pupae or scenting naive ones changed nothing, so residue on the pupal case does not explain the adult aversion. Third-instar training survived two larval molts but not metamorphosis. By analogy with Drosophila the authors place the memory in late-forming mushroom-body neurons that keep their projections through pupation, a hypothesis they did not test. | Read |
| NOTE-1258 | The stability of memories during brain remodeling: A perspective | A perspective, typed an addendum, with no new data. Learned behaviour is reported to survive brain remodelling in metamorphosing insects (odour-shock aversions in Drosophila and Manduca), regenerating planaria (McConnell’s 1960s savings and the authors’ 2013 place learning) and hibernating squirrels and marmots (hippocampal dendrites pruned in torpor, operant memory kept after six months). The authors argue that synaptic plasticity alone cannot explain lasting memory, posit a non-synaptic “blueprint”, and propose that a planarian’s memory may be stored outside the brain and imprinted on the new one, perhaps through neoblasts or bioelectric networks. The insect mechanism is called unknown; the planarian one untested. | Read |
| NOTE-1281 | Parental olfactory experience influences behavior and neural structure in subsequent generations | Male mice fear-conditioned to acetophenone or propanol before mating had sons and grandsons, never exposed to either odour, who startled more to, and detected at lower concentrations, the odour their grandfather or father had learned, and not the other. Sons and grandsons of acetophenone-trained males had more olfactory neurons carrying its receptor (M71, gene Olfr151) and larger M71 glomeruli; the anatomy, not tested behaviourally, held in IVF offspring carried by surrogates. Mothers conditioned before mating gave the same results, which survived cross-fostering. Olfr151 was less methylated in F0 and F1 sperm (n = 12 vs 10; 4 vs 4), not in the olfactory epithelium. The authors call it inherited sensitivity to a salient cue, not inherited fear. | Read |
| NOTE-1283 | Remembrance of Brains Past | The authors of Shomrat and Levin 2013 announce its result on a community blog. Planarians trained to a laser-etched chamber recognised it, by eating liver there sooner than naive worms, and recognised it again after head removal and regeneration, given a brief refresher. An automated device trained 12 worms at a time, around the clock, scored by computer, to meet the objections to McConnell’s hand-run work. The authors infer that memory can be stored outside the brain and imprinted on a new one, and suggest bioelectric networks of non-neural cells as the store. No numbers or controls are reported. | Skimmed |
| NOTE-1313 | Mental Hoop Diaries: Emotional Memories of a College Basketball Game in Rival Fans | Twenty-three male fans, 12 of Duke and 11 of UNC, watched an archived 2001 Duke–UNC game three times in the week before scanning. Under fMRI they saw 64 clips, each ending as a shot was released, and recalled whether it went in (74% correct). The same shot was good for one side and bad for the other, so allegiance alone set its valence; fans’ ratings matched their side 88.9% of the time. Good shots for one’s own team were recalled more accurately and confidently and rated more intense. Intensity, not valence, modulated amygdala, hippocampus, striatum and cortical midline regions. Positive shots added dorsal fronto-parietal and sensorimotor activity. The two fan groups did not differ in accuracy or rated intensity. | Read |
| NOTE-1350 | Sengupta, Tozzi, Cooray, Douglas and Friston — Towards a neuronal gauge theory | An essay proposing that variational free-energy minimization be cast as a gauge theory. The only connection it names is the Levi-Civita connection of the Fisher information metric on the manifold of a belief’s sufficient statistics, so its gauge freedom is reparameterization of the variational family; its claimed payoff is that attention is precision weighting forced by that manifold’s curvature. No gauge group, invariant Lagrangian or compensating field is written down. | Read |
| NOTE-1383 | Medrano, Friston and Zeidman — Linking fast and slow | A review for neuroimagers: multiscale time series are best tested with hierarchical generative models in which each level is a slower timescale, justified by centre-manifold and adiabatic reduction (the slaving principle) and compared by variational free energy; the worked example is adiabatic DCM of NMDA-receptor-antibody mouse LFP (Rosch et al. 2018). It states the slaving principle and the HKB model in a paragraph each, with no equations, and asserts rather than shows that the principle extends to discrete switching models such as HMMs. | Read |
| NOTE-1498 | Metzinger — Minimal phenomenal experience | A conceptual paper. It proposes “minimal phenomenal experience”, the phenomenology of pure awareness in meditation, as the entry point for a minimal-model explanation of consciousness. Six phenomenological constraints are drawn from contemplative and Western texts and illustrated by sixteen quoted reports. The hypothesis: pure awareness is a temporally thin, nonegoic model of the organism’s tonic alertness, “an internal model of an epistemic space”. It has representational content, lacks a first-person perspective, time, space and even phenomenal oneness, and cannot itself be remembered. | Read |
| NOTE-1508 | Jennings — Attention as the Source of a Free Will | A hybrid account of attention: prioritization by a subject that is a collection of fixed, formed and fluid interests, distinguished from filtering by feedback from dorsolateral prefrontal cortex. The subject’s power over its interests is said to be contextually emergent, made possible by a boundary from its context, and visible in phase-amplitude coupling. Attention breaks stalemates between equally weighted interests and forms new ones, which the paper offers as the source of a free will without Kane’s indeterminism. The metaphysics is argued from an analogy with Bénard cells, and the neural evidence does not separate it from the weakly emergent models it rejects. | Read |
| NOTE-1516 | Anastassiou et al. — Ephaptic coupling of cortical neurons | In rat cortical slices with synapses blocked, LFP-sized extracellular fields applied by an electrode moved somatic membrane potential by less than 0.5 mV, undiminished to 100 Hz, and with spiking driven by current they shifted spike timing without changing spike counts. Phase locking was strongest for slow fields (significant from 0.74 mV/mm at 1 Hz) and needed fields nearly ten times larger at 30 Hz. Four nearby neurons were synchronized by one field. The authors read this as a consequence of Kirchhoff’s laws and a threshold model. | Read |
| NOTE-1517 | Voigt — How hard decisions shape our preferences | An Opinion article, not a review: a “tentative, integrative neural process model” of how preferences form during choices between equally liked items. Value is computed (vmPFC), conflict detected (dACC); then, during the choice, how long an item is fixated predicts its choice and its later change in value, with precuneus allocating spatial attention bottom-up to a salient item and dlPFC holding it in working memory; the change lasts only for choices that are remembered (hippocampus). The evidence is correlational, mostly the author’s 2019 study. | Read |
| NOTE-1528 | Szczepanski et al. — Phase-amplitude coupling and spatial attention | In eight epilepsy patients with subdural grids, broadband high gamma (70–250 Hz) power rose over frontal, parietal and visual cortex while spatial attention was held, and its amplitude was coupled to the phase of a 2–5 Hz rhythm in 123 of 273 electrodes. In 28 of those 123, the coupling’s strength on a trial correlated with faster reaction times (e.g. r(41) = −0.51), for contralateral attention only. The evidence is correlational; “facilitate” in the title is the authors’ reading of it, and the paper reports no intervention. | Read |
| NOTE-1529 | Donoghue, Schaworonkow & Voytek — Methodological considerations for neural oscillations | A methods review with simulations: seven ways field-potential analyses misread oscillations (absent oscillations, shifted peaks, aperiodic 1/f activity, bursts, non-sinusoidal shape, overlapping sources, low SNR), each with a recommendation. Non-sinusoidal waveforms produce significant phase-amplitude coupling with no interaction between rhythms, and aperiodic activity puts power in every band, so neither PAC nor band power is by itself evidence of coupled oscillations. | Read |