NeurIPS 2026 Papers

Zero-shot visual decoding from electroencephalography (EEG) aims to infer visual semantics from non-invasive neural recordings, but remains challenging due to the low signal-to-noise ratio, non-stationarity, and limited spatial resolution of EEG. Existing EEG–vision alignment methods often rely on holistic EEG embeddings, which can obscure the complementary temporal, spectral, and spatial structure underlying visual perception. We introduce a unified multiview EEG representation learning framework for aligning brain responses with visual semantic embeddings. Our method builds an EEG encoder that jointly models three complementary views: input-conditioned state-space temporal dynamics, learnable wavelet-based spectral decomposition for sample-adaptive frequency modeling, and attention-modulated graph learning for structured electrode interactions. The resulting multiview EEG embeddings are fused and aligned with pretrained visual representations in a shared semantic space using contrastive learning with EEG-specific regularization, enabling 200-way zero-shot visual classification. Experiments on THINGS-EEG benchmark show that our method achieves state-of-the-art performance, with 54.8% Top-1 and 85.6% Top-5 accuracy in the within-subject setting and 15.3% Top-1 and 45.4% Top-5 accuracy in the cross-subject setting. We further present the first systematic cross session EEG–image decoding evaluation, achieving 40.8% Top-1 and 78.0% Top-5 accuracy. These results suggest that explicitly modeling multiview neural structure improves both semantic alignment and generalization in EEG-based visual decoding.

Geometric data pruning methods, while practical for leveraging pretrained models, are fundamentally unstable. Their reliance on extrinsic geometry renders them highly sensitive to latent space perturbations, causing performance to degrade during cross-architecture transfer or in the presence of feature noise. We introduce TopoPrune, a framework which resolves this challenge by leveraging topology to capture the stable, intrinsic structure of data. TopoPrune operates at two scales, (1) utilizing a *topology-aware manifold approximation* to establish a global low-dimensional embedding of the dataset. Subsequently, (2) it employs *differentiable persistent homology* to perform a local topological optimization on the manifold embeddings, ranking samples by their structural complexity. We demonstrate that our *unified dual-scale topological approach* ensures high accuracy and precision, particularly at significant dataset pruning rates (e.g., 90%). Furthermore, through the inherent stability properties of topology, TopoPrune is (a) exceptionally robust to noise perturbations of latent feature embeddings and (b) demonstrates superior transferability across diverse network architectures. This study demonstrates a promising avenue towards stable and principled topology-based frameworks for robust data-efficient learning.

LLM agents increasingly rely on reusable skills for multi-step reasoning, tool use, and decision making. Yet most existing approaches represent a skill as a prompt, module, or direction in representation space. This view can be insufficient for agentic settings: (1) the behaviour induced by a skill can depend on the current context, and (2) composing two skills can yield order-dependent rollouts. We formalise a skill realization as a local map from continuous intervention coordinates to a readout representation. Its differential defines the context-dependent controllable distribution, and the residence-space norm induces a metric on this distribution. Skill objectives then define local vector fields on these controllable directions. Their \emph{Lie bracket} captures the order-dependent component of skill composition, revealing behaviour that cannot be represented by a single context-independent direction. Our central measurement is a finite-difference skill commutator, which estimates the non-commutative component of two-skill composition from paired ordered rollouts. Unlike standard Lie-bracket estimation, the relevant vector fields are induced by skill objectives and observable ordered rollouts rather than given analytically. We therefore reconstruct the commutator from paired ordered rollouts, preserving the direction of the order-dependent change in representation space. We instantiate the framework on frozen LLM agents using activation-based and prefix-based skill realizations. Same-skill activation and prefix Jacobians are more aligned than cross-skill pairings (Cohen’s $d=-0.76/-0.26$), but they assign different control costs; separately, the measured two-skill interaction predicts ordered-composition gaps (Spearman $\rho_S=0.918/0.889$). High-commutator skill pairs also yield non-saturating reachability signals, with positive spectral-entropy gains and principal-angle novelty, while synthetic bracketed systems validate the finite-difference estimator. Together, these results show that skills form context-dependent geometric objects whose compositions leave measurable vector-valued non-commutative residuals.

Humans systematically misrepresent probability in a stereotyped inverse-S pattern. It has been documented for decades, but its origin remains unexplained. We propose a Bayesian encoding–decoding account in which probabilities are represented by noisy internal signals and decoded by Bayes-risk minimization. For bounded probability stimuli, we show that distortion decomposes into boundary regression, likelihood repulsion, and prior attraction, yielding a key prediction: the classic inverse-S-shaped weighting pattern implies a U-shaped allocation of encoding precision with greater sensitivity near 0 and 1. Across judgment of relative frequency, lottery pricing, and risky choice, this U-shape is recovered from data without imposing any functional form on the encoding, and our framework outperforms deterministic weighting functions, bounded log-odds models, uniform-encoding Bayesian accounts, and matched efficient-coding models on held-out data. In a new dot probability estimation experiment with bimodal stimulus statistics, the recovered prior tracks the new distribution while the recovered encoding remains U-shaped. Together, these results identify the inverse-S-shaped probability weighting function as the joint product of a stable U-shaped encoding and a flexible prior, integrated by optimal Bayesian decoding.

Tabular encoders are usually evaluated inside task-specific end-to-end pipelines, so models from different training paradigms are difficult to compare directly even when they operate on similar tabular signals. We introduce TRL-Bench, a multi-granular tabular representation learning (TRL) benchmark that standardizes cross-paradigm representation-level evaluation: each encoder exports row-, column-, or table embeddings through its supported wrapper, and shared lightweight heads probe them across three suites: TRL-CTbench (column/table), TRL-Rbench (row), and TRL-DLTE (compositional Data-Lake Table Enrichment spanning all three granularities). To support this standardized setting, we release curated benchmark assets and task reformulations, including 50 OpenML tables with 123 verified targets, 16 row-pair linkage rewrites, and a 47,772-table DLTE lake derived from 1,379 parent tables. Across 20 models and 16 tasks, TRL-Bench shows that once downstream conditions are standardized, encoder quality is capability-specific rather than captured by a single leaderboard. At the column/table level, generic text encoders often lead on tasks with strong surface-text signal, while tabular specialists win where their pretraining objective aligns with the task. At the row level, within-table prediction and cross-table linkage favor different training regimes, with the row-matching stage of DLTE pipelines correlating strongly with atomic linkage performance. In TRL-DLTE, the strongest pipelines combine capability-matched specialists rather than reuse a single encoder, and top end-to-end quality depends on non-additive compositional fit rather than per-stage marginal rank alone. TRL-Bench provides a common protocol for measuring reusable signal in exported tabular representations under shared downstream conditions.

When an omnimodal large language model accepts a question whose textual premise contradicts what it actually sees or hears, does the failure lie in perception or in action? Recent omnimodal models are positioned as perception-grounded agents that jointly process video, audio, and text, yet a basic form of grounding remains untested: catching a textual claim that conflicts with the model's own sensory input. We introduce IMAVB, a curated 500-clip benchmark of long-form movies with a 2x2 design crossing target modality (vision, audio) and premise condition (standard, misleading), which lets us measure conflict detection separately from ordinary multimodal comprehension. Across eight open-source omnimodal LLMs and Gemini 3.1 Pro, we document a Representation-Action Gap: hidden states reliably encode premise-perception mismatches even when the same models almost never reject the false claim in their outputs. Behaviorally, models fall into two failure modes: under-rejection, in which they answer misleading questions as if the false premise were true; and over-rejection, in which they reject more often but also reject standard questions, sacrificing ordinary comprehension accuracy. The gap is modality-asymmetric (audio grounding underperforms vision) and prompt-resistant across seven variants. As an initial diagnostic intervention, a probe-guided logit adjustment (PGLA) re-injects the encoded mismatch signal into decoding and consistently improves rejection behavior. Together, these results suggest the bottleneck for omnimodal grounding lies in translation, not perception.

The landscape of self-supervised learning (SSL) is currently dominated by generative approaches (e.g. MAE) that reconstruct raw low-level data, and predictive approaches (e.g. I-JEPA) that predict high-level abstract embeddings. While generative methods are stable due to their reliable training targets based on ground-truth data, they are computationally inefficient for high-redundancy modalities like imagery, and their training objective does not prioritize learning high-level, conceptual features. Conversely, predictive methods often suffer from training instability due to their reliance on the non-stationary targets of final-layer self-distillation. We introduce Bootleg, a method that bridges this divide by tasking the model with predicting latent representations from multiple hidden layers of a teacher. This hierarchical objective forces the model to capture features at varying levels of abstraction simultaneously. We demonstrate Bootleg significantly outperforms comparable baselines (+10% vs. I-JEPA) on frozen probe classification of ImageNet-1K, iNaturalist-21, and VTAB, and semantic segmentation of ADE20K, Cityscapes, and COCO-Stuff.

Diffusion transformers learn useful internal representations during training, and learning them from scratch can add a burden to efficient training. Alignment mitigates this burden by adding an auxiliary loss that regularizes diffusion hidden states with features from pretrained visual encoders. In this work, we revisit the role of this alignment signal. Rather than using pretrained representations only as a regularizer during full diffusion training, we use them as a preconditioning signal before diffusion training. The key observation is that early layer alignment from clean latents to pretrained representations can be much cheaper than optimizing the full flow matching objective over the entire backbone, yet provides a better initialization for subsequent diffusion training. We instantiate this idea as Embedded Representation Warmup (ERW). ERW first aligns early layers from clean latents to pretrained representations, and then trains the full model with the standard diffusion objective and decaying alignment. This initialization allows subsequent diffusion training with alignment to converge more efficiently than starting alignment from scratch. Counting warmup in the total budget, ERW improves convergence in SiT based diffusion training. On ImageNet $256\times256$, ERW reaches FID=1.41 in 350 epochs with SiT-XL/2; it also reaches FID=2.04 on ImageNet $512\times512$ and improves FID on MS-COCO text-to-image generation.

Scaling reinforcement learning (RL) to diverse multitask settings remains a central challenge. While recent advances in model-based RL achieve strong performance, they rely on planning and complex training pipelines, making it unclear which components are essential for scalability. We revisit this question and argue that the primary driver of scalable multitask RL is not model-based control, but _representation learning_. In particular, we show that combining predictive, model-based representations with high-capacity value function approximation is sufficient to achieve strong performance, without planning. We evaluate a simple model-free algorithm, MR.Q, that integrates auxiliary predictive objectives into a scalable actor-critic architecture. This approach outperforms a recent world-model-based method and a range of deep RL baselines across a diverse suite of multitask continuous control tasks, while significantly reducing computational overhead and improving wall-clock efficiency. We observe consistent improvements with increased model capacity and show through ablations that predictive representation learning is critical for performance.

Unified multimodal models (UMMs) aim to handle perception and generation in a single model. Yet existing UMMs still rely on a frozen, separately pretrained VAE for image generation, imposing a structural bottleneck. Naively removing it introduces a quality gap, as the model must learn both high-level structure and low-level details from raw pixels. In this paper, we propose Representation Forcing (RF), a technique that closes this gap by making representation prediction a native capability of the decoder. Concretely, RF forces the decoder to autoregressively predict visual representations as intermediate tokens before pixels; these tokens then stay in context to guide pixel diffusion within the same backbone. By turning representations from perception outputs into generation targets, RF eliminates the need for any external generative latent space. We find that RF benefits both understanding and generation. On image generation, our pixel-space model with RF matches state-of-the-art VAE-based unified models. On image understanding, pixel-space RF generally outperforms its VAE-based variant. Together, these results offer an effective step toward end-to-end, bottleneck-free UMMs.

We study representation learning in low-rank Constrained Markov Decision Processes (CMDPs), where both value and reward functions are approximated by a set of unknown representation vectors, and the transition dynamics admit a low-rank factorization. The objective is to maximize expected cumulative rewards while complying with constraints on the expected cumulative utility. To achieve this, we propose \texttt{MFRLC} (Model-Free Representation Learning for Low-Rank CMDP), a model-free algorithm that uses a primal-dual scheme to effectively balance reward regret and constraint violations. To the best of our knowledge, \texttt{MFRLC} is the first representation-learning method for low-rank CMDPs that combines the Least-Squares Value Iteration with Upper Confidence Bound (LSVI-UCB) and primal-dual techniques. \texttt{MFRLC} further enhances value function estimation with bonuses for function approximation and uniquely learns the mapping from representations to value functions directly through representation learning. We prove that \texttt{MFRLC} achieves both regret and cumulative constraint violation of order $\widetilde O(H^3 d^2 K^{3/4}|\mathcal{A}|^{3/2}/\gamma)$, making it provably sample-efficient and highly adaptable to complex environments due to the reliance on function approximation.

Representation learning has substantially improved the efficiency of unconstrained continuous-state Markov Decision Processes (MDPs), but its extension to Constrained MDPs (CMDPs) is difficult because the transition representation must be learned while constraint violation is controlled. In this paper, we study representation learning for low-rank CMDPs with continuous state spaces, and propose REP-PD-TEG for the soft cumulative-violation setting. In the feature learning period, the algorithm interacts with the environment using a decaying-$\epsilon$-greedy mixture execution policy, and uses the collected samples to learn transition features by maximum likelihood. Based on the learned features, it constructs uncertainty bonuses and plans with an optimistic Lagrangian objective to obtain the return policy. We prove regret and soft-violation guarantees for the return policies, and quantify the influence of the decaying-$\epsilon$-greedy exploration. In particular, REP-PD-TEG achieves the optimal \(\widetilde O(\sqrt K)\) return policy bound, and gives a \(\widetilde O(K^{3/4})\) overall sample bound when exploratory actions are charged. For the stricter hard cumulative violation, where feasibility must be verified episode by episode, we propose REP-PD-H-TEG. It plans under a bonus-corrected lower-confidence utility certificate with the learned representation, and performs a stabilized dual search to obtain the return policy, yielding regret and hard-violation bounds. Together, these results give the first theoretically guaranteed representation-learning method for low-rank continuous-state CMDPs with both soft cumulative guarantees and certified hard-violation control.

In long-term multi-session neural recordings, the same latent population dynamics are often observed through changing subsets of neural channels due to electrode drift, signal instability, or session-dependent recording variability. This creates a partially observed system-identification problem: each session provides only an incomplete view of a shared dynamical system, and missing channels are not merely absent inputs but unobserved variables coupled to the same latent dynamics. Existing approaches often rely on observation-pattern-specific mapping, which treats missing channels passively and leaves the shared latent dynamics weakly constrained. We propose CHAMA (CHannel-Aware Masked Attention), a mask-conditioned predictive representation learning framework for identifying shared neural dynamics under heterogeneous channel availability. CHAMA introduces a single global observation interface conditioned on channel-availability masks, allowing observed and unobserved channels to jointly constrain latent dynamics. The key idea is bidirectional: missing channels impose structural constraints on the latent representation, while the learned latent dynamics enable principled recovery of missing activity. To improve identifiability under sparse observations, CHAMA aggregates causal temporal windows, effectively trading temporal context for missing spatial information. Across synthetic dynamical systems and real multi-session neural recordings, CHAMA improves missing-channel completion, forecasting, latent dynamical fidelity, and downstream behavioral decoding over conditional adapter, zero-padding, and masked-autoencoding baselines. These results show that dynamics-aware recovery preserves globally consistent and behaviorally relevant structure beyond point-wise reconstruction accuracy. The source code is available at: \url{https://anonymous.4open.science/r/CHAMA-D691}.

Neural Sheaf Diffusion (NSD) generalizes diffusion-based Graph Neural Networks by replacing scalar graph Laplacians with sheaf Laplacians whose learned restriction maps define a task-adapted geometry. While the diffusion limit of NSD is known to be the space of global sections, the representation-theoretic structure of this harmonic space remains largely implicit. In this paper, we develop a quiver-theoretic interpretation of NSD by identifying cellular sheaves on graphs with representations of the associated incidence quiver. Under this correspondence, learned sheaf geometries become points in a finite-dimensional representation space. We prove that direct-sum decompositions of the underlying incidence-quiver representation induce corresponding decompositions of the harmonic space reached in the diffusion limit. This provides an algebraic interpretation of oversmoothing as representation degeneration: a conceptual framing where learned sheaves collapse toward trivial or low-complexity summands whose global sections fail to preserve discriminative information. Building on this viewpoint, we connect sheaf diffusion to stability, moduli, and moment-map principles from Geometric Invariant Theory. We introduce moment-map-inspired regularizers that bias learned restriction maps toward more balanced representation geometries, and we identify a structural obstruction in standard equal-stalk architectures: when $d_v=d_e$, the admissibility condition for learnable stability parameters forces the trivial all-object summand onto a stability wall. We show that non-uniform stalk dimensions remove this obstruction, making adaptive stability meaningful in principle. Empirical evaluations on heterophilic benchmarks are consistent with this mechanism: breaking stalk symmetry can reduce variance or improve validation behavior on some datasets, and adaptive stability regularization becomes more effective in selected rectangular settings. These results support the view that moment-map regularization is a structured but dataset-dependent geometric bias rather than a universal performance booster. Overall, our framework interprets oversmoothing not only as a spectral pathology, but as a degeneration phenomenon in the underlying representation geometry.

The Representation Autoencoder (RAE) shows that a frozen high-dimensional semantic ViT representation enables both image reconstruction and DiT-based generation. However, RAE's semantic-only representation lacks appearance details, yielding suboptimal reconstruction. Full fine-tuning the encoder with reconstruction loss induces catastrophic semantic collapse: the encoder overfits to appearance, loses semantic discriminability, and cripples generation. This failure arises because the reconstruction loss imposes an appearance prior that erodes semantic structure. To resolve this conflict, we propose Semantic Structure Regularization (SSR). SSR builds on self-distillation, using a learnable student and a frozen teacher that retains the original semantics. In addition to standard latent alignment, which forces the student's representation to match the teacher's, we introduce two complementary regularizers that prevent appearance overfitting from corrupting semantic structure. First, spatial self-similarity distillation forces the student to reproduce the teacher's patch-wise relational patterns. Invariant to appearance changes, this relational signature anchors high-order semantics and prevents the sacrifice of structure for pixel fidelity. Second, structure-anchored alignment decouples structure from appearance. Using a frequency-domain transform, we extract a high-frequency structural map (edges, boundaries) from each image while discarding low-frequency appearance. The teacher's representation of this structural map then regularizes the student's representation of the original image. Consequently, the student learns appearance details from the reconstruction loss without penalty, where the regularization enforces only structural consistency and enables pixel-level encoding without semantic drift. The result is a unified representation that excels at high-fidelity reconstruction, discriminative perception, and efficient DiT-based generation. Our work provides a principled path toward a single semantic space bridging perception and generation, challenging the classic dichotomy. Code and models will be released.

Understanding how cortical activity represents natural whole-body behavior in primates remains challenging. Limited by diversity of movements and inaccessible of large-scale neural feature programming whole-body kinematics, previous motor decoding studies rely on constrained tasks and limited limb movements. Here, we present a neural-behavioral recording and modeling framework for freely moving monkeys, combining epidural cortical signals from distributed sensorimotor areas with synchronized multi-view motion capture through a data custom collection platform. We reconstruct whole-body monkey kinematics and learn a compact motion prior using an autoregressive encoder-decoder model. Conditioned on epidural signals, the model decodes more accurate and realistic full-body movements without explicit physical constraints. Our results provides a novel proof-of-concept approach for decoding natural whole-body movements in primates using large-scale intracranial neural activity.

Learning effective representations from battery operational history is essential for predictive health management and control-oriented applications. Existing approaches rely on response-dependent engineered features or short early-life windows, limiting generalisability and precluding use in prospective settings where future responses are unavailable. We propose $\texttt{NOCE-Net}$, a deep nested sequence model that learns control-enabling representations directly from raw cyclic operational data. Our data pipeline, $\texttt{re-BatteryData}$, standardises heterogeneous aging datasets into semantically equivalent Full Equivalent Cycles (FECs) defined by absolute charge throughput, enabling end-to-end learning across diverse operational regimes. $\texttt{NOCE-Net}$ combines multi-patch transformer encoders for intra-cycle dynamics with a GRU backbone for inter-cycle state evolution, operating on approximately $700$ batteries across ten public datasets spanning over $300$ operational profiles. In zero-shot evaluation on unseen battery chemistries and usage patterns, $\texttt{NOCE-Net}$ achieves $13.7$% MAPE in voltage response prediction, outperforming strong long-sequence baselines by over $43$% while using $40 \times$ fewer parameters. Shape and component diagnostics of the learned hidden states reveal that the GRU's principal direction of evolution achieves Spearman $|\rho| \geq 0.95$ with the capacity fade trajectory on average across all datasets with monotone degradation profiles, including zero-shot test batteries, providing evidence that the representations encode degradation dynamics transferable to downstream tasks beyond battery response modelling.

Implicit neural video representations offer compact, continuous alternatives to conventional codecs, but higher reconstruction fidelity typically requires more computation per decoded frame. We introduce NIKA, which shifts video-specific capacity from the decoder into a structured latent state, allowing reconstruction quality to scale with latent expressivity while keeping active decoding lightweight. NIKA constructs this state from complementary spatial, spectral, and temporal bases, then decodes it with lightweight ConvNeXt-style convolutional upsampling. On UVG, a 2.91M-parameter NIKA model achieves 33.33 dB PSNR at 462 decoding FPS with 4.5G MACs on an RTX A5000, outperforming comparable single-resolution NeRV-family baselines while using 39--51$\times$ fewer MACs. Ablations show that diversifying latent components improves reconstruction more reliably than reallocating capacity within a single component, and qualitative analysis reveals specialization among components. Together, these results identify structured latent diversity as a practical alternative to scaling decoder complexity for high-fidelity, efficient neural video representation.

Continual learning requires models to adapt to new data while preserving previously acquired knowledge. At its core, this challenge can be viewed as principled one-step adaptation: incorporating new information with minimal interference to existing representations. Most existing approaches address this challenge by modifying model parameters or architectures in a supervised, task-specific manner. However, the underlying issue is representational: tasks require distinct yet structured representations that can be selectively updated without disrupting representations, while structure should reflect intrinsic organization in the data rather than task boundaries. In sequential data, time-delayed dependencies provide a natural signal for uncovering this organization, revealing how fundamental representations give rise to more specific ones. Inspired by the modular organization of the human brain, we propose MoRe, a framework that identifies modularity in the representation itself rather than allocating it at the architectural level. MoRe decomposes knowledge into a hierarchy of fundamental and specific modules with identifiability guarantees, enabling principled module reuse, alignment, and expansion during adaptation while preserving old modules by construction. Experiments on synthetic benchmarks and real-world LLM activations demonstrate interpretable hierarchical structure, improved plasticity-stability trade-offs, suggesting MoRe as a principled foundation for continual adaptation.