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brain_graph_1

11 captures, most recent first.

unclear (appears to be Nathan's own brain_graph_1 project script output)

| Component | Trainable params | Source |al) Counted dire— ───────────────────────────────────────── s | params | | Sharded macrocolumn cortex (425,393 | 184,354,125 | banner param_count() over | | | macrocolumns) | | requires_grad | Counted dire— Component | Trainable ─────────────────────────────────────────s • ├ — — | 184,354,125 | ba ner param_count() over────────────| | Sharded macrocolumn cortex (425,393 | | requires_gradount() over | | | Backbone (RWKV nodes, MONET keys, heads, | 37,302,731 | optimizer exp_avg entries (one | | | BG/motor/hippo/grid/etc.) | | moment per optimized param) | | Total trainable | ≈ 221.7 M | The macrocolumn cortex is 88% of the trainable weights — as expected, it's the whole point of the sharded run (it's also why N=425k doesn't fit one 24 GB card and needs the 2-way split). N te on the bigger number you'd see h̶u̶ external-drive/ 5 shells • buffers: EMA target encoders, CSR/edge-tructure tensors, divnorm running-σ, fast-plastic • local_learning traces (13.6 M), surprise memory (4.8 M), etc. Those don't get gradients, so they're not in the "trainable" count. • - The macrocolumn block's own per-shard optim[izers] are built at runtime and aren't in thiso checkpoint's exp_avg, which is why I took its trainable count from the startup banner's param_count() stead — the two method cover disjoint halves, so they sum cleanly. So: ~222 M trainable, ~184 M of it in the GPU-sharded cortex, with another ~73 M of non-trained [buffers/state cut off at bottom of visible screen]
Note from Claude Sonnet 5

A terminal screenshot with garbled/overlapping text rendering (two overlapping renders of what appears to be the same markdown table, likely a scroll/redraw glitch), showing a parameter-count breakdown for a "sharded macrocolumn cortex" neural architecture — matches the brain_graph_1 project's known architecture (RWKV nodes, macrocolumns, basal ganglia/hippocampus/grid components). Text is partially garbled by rendering overlap, not genuine content loss.

brain_graph_1neural architectureterminal outputmachine learningparameter counts

Joey (e/λ @shxf0072

diff between future and predicted future states is reward [Embedded diagram: same ICM figure as previous screenshot — forward model predicting φ̂(s_t+1), compared (−) against actual φ(s_t+1) to produce intrinsic reward r^i_t; inverse model predicts action â_t from φ(s_t), φ(s_t+1).] 💬1 🔁 ❤️4 📊218 🔖 ⤴ Joey (e/λ) @shxf0072 · 2h forward model is trying to predict future latent given current so it works like curiosity while inverse model teachs what to ignore encoder learns to ignore noise like trees leave since it doesn't help inverse models predict which action was taken [Embedded diagram, repeated: full ICM architecture — agent state s_t, policy π producing action a_t, environment E transitioning to s_t+1, action a_t+1 via π, ICM module consuming s_t/a_t/s_t+1 to produce intrinsic reward r^i_t, combined with extrinsic reward r^e_t.]
Note from Claude Sonnet 5

Continuation of the same ICM (Intrinsic Curiosity Module) thread — explains the intuition that the inverse dynamics model (predicting the action taken from consecutive states) forces the feature encoder to discard action-irrelevant noise (like windblown leaves), so the forward model's prediction error in that cleaned feature space becomes a principled curiosity/novelty signal. Same relevance as the previous screenshot: architecture pattern applicable to brain_graph_1's intrinsic-motivation/curiosity design.

reinforcement learningcuriosity-driven explorationintrinsic rewardicmrepresentation learningbrain_graph_1

Joey (e/λ @shxf0072

Joey (e/λ) @shxf0072 this example is from rl paper, one of the best one curiosity driven exploration, if you squint eyes hard enough you can find jepa like arch trained end to end with rl [Embedded image: page from a paper, "Curiosity-driven Exploration by Self-supervised Prediction" — Figure 2 diagram of an agent interacting with environment via policy π, ICM (Intrinsic Curiosity Module) computing intrinsic reward r^i from states s_t, s_t+1; right side shows ICM internals: forward model predicting φ̂(s_t+1) from φ(s_t) and a_t, inverse model predicting â_t from φ(s_t), φ(s_t+1), compared against actual a_t. Caption explains: agent optimizes sum of extrinsic reward r^e and curiosity-based intrinsic reward r^i; prediction error in feature space (not pixel space) is the curiosity signal, making exploration robust to uncontrollable environment aspects. Below, section 2.1 "Prediction error as curiosity reward" discusses why raw pixel-space prediction is undesirable (e.g. unpredictable leaf motion causing an "artificial curiosity trap"), and the need for a feature space that models controllable/agent-affecting elements while ignoring irrelevant background variation. Two passages hand-underlined in red: the paragraph about prediction error being unclear as an objective, and the passage about no known computationally feasible mechanism for measuring learning progress instead of prediction error.]
Note from Claude Sonnet 5

A tweet highlighting the classic Intrinsic Curiosity Module (ICM) paper (Pathak et al., "Curiosity-driven Exploration by Self-supervised Prediction") as an early example of a JEPA-like (joint embedding predictive architecture) approach trained end-to-end with RL — predicting in learned feature space rather than raw pixels to generate intrinsic/curiosity reward. Directly relevant to Nathan's brain_graph_1 project, which uses PVLV dopamine and curiosity-style intrinsic motivation signals; ICM's forward/inverse-model feature-space prediction is a foundational architecture pattern for that kind of RL exploration design.

reinforcement learningcuriosity-driven explorationintrinsic rewardjepaself-supervised learningicmbrain_graph_1ai research paper

@spisaktamas

Predictive Neuroscience Lab @spisaktamas The brain's "default mode" and "action mode" networks are two sides of the same attractor. Encoding a macro-scale Bayesian prior that biases processing toward internal or external drive. [Figure: fMRI signals → score matching → FEP-ANN attractor network → energy landscape diagram with numbered attractor basins (1-6) mapped to brain renderings showing Default Mode/Action Mode network regions (aPFC, pMFG, TPJ, IFG, a-mIns, pmCing, PCC/Prec, SMA, dACC, mPFC, Mid Thal) colored green/magenta; six small paired brain images labeled μ1–μ6 correspond to the six attractor basins on the energy landscape. Citation: Englert et al., 2024, Spisak & Friston 2...] 1:44 PM · Apr 28, 2026 · 3,357 Views
Note from Claude Sonnet 5

A neuroscience research tweet on free-energy-principle (FEP) modeling of the brain's default-mode/action-mode networks as attractor states in an energy landscape, derived via score-matching on fMRI data and an ANN. Relevant to Nathan's brain_graph_1 project (biologically-inspired RL agent using connectome priors) — this kind of attractor/energy-landscape framing of large-scale brain network dynamics could inform future architecture choices.

neurosciencefree energy principledefault mode networkpredictive codingfmriattractor networksbrain_graph_1

ueaj @_ueaj

ueaj @_ueaj · 18h New blog! You can just keep increasing the amount of heads in your model with no diminishing returns on ICL up to atleast 4x. For reference that would make the o_proj head dimensions in this experiment 16k x 2k. Additionally, if you perform a truncated SVD on full rank master weights to train MLA instead of training them as two separate matrices, you can recover most of the ICL capability but with less memorization. I think MLA specialized optimizers are a direction worth exploring and are very underserved rn. Unfortunately I have more important projects to attend to and I've burned like 300$ on compute for this already. I would highly recommend someone trying to scale this up and see how well we can do. [Chart: "arc/output_loss" — lines for mla-rat-l512-r64-b0p9-arc1-200m, mla-base-l512-r64-b0p9-arc1-200m, quad-kv-b0p9-arc1-200m, single-kv-b0p9-arc1-200m, x-axis train/tokens_seen 20M-180M, y-axis loss 0-8, all converging to similar low loss; tooltip shows single-kv-b0p9-arc1-200m: 0.74451, quad-kv-b0p9-arc1-200m: 0.66843 at 199,884,800 tokens] ueaj @_ueaj · Apr 15 Replying to @_ueaj Also something like MLA should be trained like QAT but instead of converting a high precision matrix to low precision you convert a full rank master weights into low rank latent projections...
Note from Claude Sonnet 5

A technical thread on Multi-head Latent Attention (MLA) architecture experiments — scaling attention heads without diminishing ICL returns, and using truncated SVD on full-rank weights (analogous to quantization-aware training) to recover in-context-learning capability with less memorization. Directly relevant to the brain_graph_1 "KDA-MLA attention at the ends only" architecture plan noted in project memory.

machine learningattention mechanismsmlamulti-head latent attentionin-context learningtwitterueajbrain_graph_1architecture research

Albert Gu @_albertgu

quoting Hayden Prairie (@hayden_prairie)

Albert Gu @_albertgu · Apr 16 a dynamical systems point of view, which looks like an SSM applied along the residual stream, informs more principled ways to scale looped architectures > QUOTED: > Hayden Prairie @hayden_prairie · Apr 15 > We've been thinking a lot about scaling laws, wondering if there is a more effective way to scale FLOPs without increasing parameters. > > Turns out the answer is YES – by looping blocks… > > [Diagram: recurrence block h_t → Ā, Δ, B̄ (SSM-style gating) feeding into a "Transformer Blocks" module (Multi-Head Attention + Feed Forward, residual connections) → h_t+1] > [Two plots: "IsoFLOP Scaling Laws of Looping" — Validation Loss vs Recurrence (multiple colored curves with star-marked optima), and Optimal Recurrence vs FLOPs (log-log, roughly linear trend)]
Note from Claude Sonnet 5

Albert Gu (Mamba/SSM researcher) comments on a scaling-laws paper/thread about looping transformer blocks with an SSM-style gate applied along the residual stream, treating it as a dynamical-systems framing for how much recurrence to use at a given FLOP budget. Directly relevant to the brain_graph_1 encode/iterate-in-latent/decode architecture and its "virtualizing width via looping" primitive — a scaling-law reference for how many DEQ/loop iterations to use at different compute scales.

machine learningssmmambalooped transformersscaling lawstwitteralbert guarchitecture researchbrain_graph_1

Jakob Foerster @j_foerst

Jakob Foerster ✓ @j_foerst · 11h There is a failure mode in research I call "nothing works and we don't know why", which can suck a lot of time and energy. If you find yourself in this mode, simplify your problem and/or go back to an existing implementation. Things that work give signal things that don't less so
Note from Claude Sonnet 5

A research-methodology tip from ML researcher Jakob Foerster about debugging strategy: when stuck in an undiagnosable failure state, simplify or revert to a known-working baseline rather than continuing to iterate blind. Practically relevant advice for Nathan's own debugging-heavy brain_graph_1 project (currently in a mid-debug phase per project memory, with a training plateau and multiple degraded signal paths under investigation).

research methodologydebuggingmachine learningtwitterbrain_graph_1

Cankay Koryak @CankayKoryak

Cankay Koryak ✓ @CankayKoryak The Rosehip Neuron is a unique, inhibitory interneuron found exclusively in the human cerebral cortex. It resides in Layer 1 (the outermost layer), a primary site for receiving regulatory feedback signals. This neuron's most crucial feature is its specific target: the apical dendritic shafts of Layer 3 Pyramidal Neurons. By inhibiting this precise location, the Rosehip neuron is positioned to exert powerful, fine-tuned control over the top-down cognitive and associative inputs that Layer 3 processes. Its apparent absence in both rodents and non-human primates makes it a compelling candidate for a cell type contributing to distinctively human cognitive functions and may hold keys to understanding uniquely human neurological disorders. [Image: electron-microscopy-style cortical tissue image labeled "Rosehip Neurons (Human-Specific)" with several highlighted (white) neuron cell bodies pointed out across cortical layers.]
Note from Claude Sonnet 5

Neuroscience explainer tweet about the rosehip neuron, a human-specific inhibitory interneuron type in cortical Layer 1 that regulates Layer 3 pyramidal neurons. Potentially relevant background reading for Nathan's brain_graph_1 project (connectome-based RL agent with cortical/subcortical structure), as species-specific cell types like this bear on questions of what's essential vs. incidental in modeling human-like cognition.

neurosciencecortexinterneuronshuman brainbrain_graph_1twitter

Surya Ganguli @SuryaGanguli

Surya Ganguli @SuryaGanguli · Nov 13 Our new paper on large scale holographic read-write experiments observing and controlling thousands of neurons in mouse visual cortex reveals a new functional cell-type that detects even moderate levels of excess activity (just 50 extra neurons firing) then inhibits top down cortical inputs. This cell type is a subclass of somatostatin neurons, whose dysfunction is implicated in schizophrenia. This suggests an intriguing hypothesis for the origins hallucinations in schizophrenia: the breakdown of this highly sensitive cortical gate allows top down inputs to enter visual cortex that should not, creating hallucinations. This work was expertly lead by @ADrinnenberg w/ @allanraventos and @Alex_Attinger on data analysis and theory. Another fun collab w/ @KarlDeisseroth! For more see: biorxiv.org/content/10.110... And also this excellent thread: x.com/ADrinnenberg/s...
Note from Claude Sonnet 5

A tweet by Stanford neuroscientist Surya Ganguli summarizing a new paper (with Karl Deisseroth's lab) on holographic read-write experiments in mouse visual cortex, identifying a somatostatin-neuron subtype that gates top-down cortical input and proposing a mechanistic hypothesis for schizophrenia hallucinations. Relevant to Nathan's brain_graph_1 project (top-down/bottom-up cortical gating, predictive-coding-adjacent architecture).

neurosciencevisual cortexsomatostatin neuronsschizophreniakarl deisserothsurya gangulipredictive codingbrain_graph_1

davinci @leothecurious

quoting Tahereh Toosi (@taherehtoosi)

davinci @leothecurious · Oct 25 predictive coding doesn't merely serve to update parameters via local credit assignment but doubles as am algorithm for inference-to-best-explanation based on observed features (bottom-up signal) and learned priors (top-down signal). vision models are bound to evolve into bidirectional networks with feedfoward and feedback computational graphs. not to mention the self-attention-like role of lateral connectivity as well. the implications will be manifold. > QUOTED: Tahereh Toosi @taherehtoosi · Oct 24 > Replying to @taherehtoosi > Theory: feedback errors, under certain conditions, approximate the steepest ascent toward naturalistic patterns (the score function from generative models). These errors act like a... > [Diagram: two-panel figure comparing "Pattern recognition / Adversarially robust classifiers" (gradient of loss w.r.t. input, ∇L_x(x,y)) against "Pattern generation / Score-based generative models" (gradient of log-density, ∇log p_θ(x)), plus a 3D loss-landscape surface with a red dashed arrow labeled ∇log p(x) climbing toward a peak]
Note from Claude Sonnet 5

A neuroscience/ML Twitter thread on predictive coding as a unifying theory linking cortical feedback connectivity to bidirectional (feedforward+feedback) computational graphs and self-attention-like lateral connectivity, with a connection to score-based generative models. Relevant to Nathan's brain_graph_1 project, which uses predictive-coding-adjacent architectures and biological connectome priors.

predictive codingneurosciencemachine learningvision modelsgenerative modelsself-attentionbrain_graph_1

Fern @hi_tysam

quoting Guan Wa... (@makingA..., Jul 21)

Fern @hi_tysam · 18h btw, one flaw of HRMs is the readout q_head will either cause representational collapse, or be ignored, or some thing in between what you really should be doing instead is curve-fitting on the abs of the cosine distance of successive vectors to determine halting, or such similar [Quoted tweet:] Guan Wa... @makingA... · Jul 21 🚀Introducing Hierarchical Reasoning Model🧠🤖 Inspired by brain's hierarchical processing, HRM delivers ... [Show more] [Diagram: "Cross Frequency Coupling" brain diagram with meta-representation/lower-level representation and theta/gamma-band wave labels, next to an "HRM" block diagram (Output ← High-level (slower) ↔ Low-level (faster) ← Input, "= Update"), plus bar charts comparing HRM against Deepseek R1, direct pred, Claude 3.7 8K, o3-mini-high on ARC-AGI-1 (40.3% HRM vs ~34.5% o3-mini-high), ARC-AGI-2 (5.0% HRM), Sudoku-Extreme 9x9 (55.0% HRM), and Maze-Hard 30x30 (74.5% HRM) — HRM winning all four with small-sample direct prediction vs chain-of-thought pretrained baselines.]
Note from Claude Sonnet 5

A critique/technical exchange about the "Hierarchical Reasoning Model" (HRM), a brain-inspired architecture (high-level slow / low-level fast loops, cross-frequency coupling analogy) that beats chain-of-thought LLM baselines on ARC-AGI, Sudoku, and maze benchmarks with small-sample direct prediction. Directly relevant to Nathan's brain_graph_1 project, which similarly uses brain-inspired hierarchical/recurrent architecture; the readout-halting critique (representational collapse in the q_head) is a concrete design pitfall to be aware of.

machine learninghierarchical reasoning modelbrain-inspired architecturearc-agitwittertechnicalbrain_graph_1