NeurIPS 2026 Papers

Conference on Neural Information Processing Systems

Decision breakdown

6,437papers

Counted from the official paper list; may differ slightly from the number the conference announced.

  • Oral
    991.5%
  • Spotlight
    2403.7%
  • Poster
    6,09894.7%

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When Language Overrules: Revealing Text Dominance in Multimodal Large Language Models

Huyu Wu, Meng Tang, Xinhan Zheng, Duo Su, Haiyun Jiang

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Text dominance, the tendency of multimodal large language models (MLLMs) to over-attend to textual tokens while under-utilizing non-text inputs, has been observed in vision-language settings, but whether it extends to other modalities remains an open question. We present a systematic, attention-level study of this phenomenon across five modalities (image, video, audio, time-series, and graph), using two diagnostic metrics: the Modality Dominance Index (MDI), which compares per-token attention between text and non-text inputs, and the Attention Efficiency Index (AEI), which normalizes attention share by token share. Across ten models and six benchmarks, text dominance is pervasive in image, video, audio, and time-series settings and intensifies in deeper layers. Controlled token-replication experiments show that expanding non-text sequences without adding semantic content amplifies the imbalance, while graph tasks provide a boundary case where compact, information-dense tokens reverse the effect. Guided by these findings, we evaluate attention-based token compression as a proof-of-concept intervention on the vision modality. On LLaVA-1.5-7B with MMMU-Pro, removing 90\% of visual tokens via informed selection preserves accuracy (33.70\% vs.\ 33.23\% baseline), while random dropping under the same ratio degrades it to 30.29\%; informed selection also lowers the late-layer MDI from 15.63 to 3.46 and reduces latency by 3.5$\times$. These results suggest that text dominance is a cross-modal phenomenon associated with token redundancy, and that token compression can reduce it in the tested vision setting while preserving task performance.

Poster
WAXAL: A Large-Scale Multilingual African Language Speech Corpus

MohamedElfatih MohamedKhair, Emmanuel Asiedu Brempong, Subhashini Venugopalan, Abdoulaye Diack, Perry Nelson, Prince Mireku, Tavonga Siyavora, Pooja Rao, Uche Okonkwo, Angela Nakalembe, Abhishek Bapna, Aisha Walcott-Bryant

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The advancement of speech technology has predominantly favored high-resource languages, creating a significant digital divide for speakers of most Sub-Saharan African languages. To address this gap, we introduce WAXAL, a large-scale, openly accessible speech dataset for 24 languages (spanning 19 for ASR and 13 for TTS, with overlaps) representing over 100 million speakers. The collection consists of an Automatic Speech Recognition (ASR) dataset containing approximately 2,340 hours of transcribed, image-prompted natural speech (over 14,100 hours of total collected audio) from a diverse range of speakers, and a Text-to-Speech (TTS) dataset with over 235 hours of high-quality, single-speaker studio recordings of phonetically balanced scripts. Crucially, this effort was executed in partnership with four African academic and community organizations, with the explicit goal of building the local ecosystem for speech technology and seeding data collection capabilities within these institutions. To demonstrate the dataset's utility, we benchmark three architecturally distinct ASR models---Gemma 3n-2B, Whisper-Large-v3, and MMS-1b-all---across the 19 ASR languages. Fine-tuning on WAXAL yields substantial improvements, reducing the macro-average Word Error Rate (WER) by up to 61\% (e.g., from 1.23 to 0.48 for Whisper). Models fine-tuned solely on WAXAL also generalize to the independently collected FLEURS benchmark, confirming the dataset's value for domain-transferable ASR adaptation. Furthermore, we employ an LLM-as-judge framework to evaluate semantic meaning preservation, demonstrating that fine-tuned predictions successfully capture core intents of native speakers. The WAXAL datasets are released at https://huggingface.co/datasets/google/WaxalNLP under the CC-BY-4.0 license to catalyze research and the development of inclusive speech technologies for speakers of African languages.

Poster
Viverra: Text-to-Code with Guarantees

Haoze Wu, Rocky Klopfenstein, Keith Farkas, Nina Narodytska

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A fundamental limitation of Text-to-Code is that no guarantee can be obtained about the correctness of the generated code. Therefore, to ensure its correctness, the generated code still has to be reviewed, tested, and maintained by developers. However, parsing through LLM-generated code can be tedious and time-consuming, potentially negating the productivity gains promised by AI-coding tools. To address this challenge, we present Viverra, a system that automatically produces *formally verified annotations* alongside generated code to aid user's understanding of the generated program. Given a natural-language task description, Viverra prompts an LLM to synthesize a C program together with candidate assertions expressing safety and correctness properties. It then verifies those assertions in a compositional and best-effort manner via a portfolio of bounded model checkers. Evaluation on 18 diverse programming tasks suggests that Viverra can efficiently generate code with verified assertions, and that these assertions improve users' performance on code-comprehension tasks in a user study with more than 400 participants.

Poster
Visual Text Compression as Measure Transport

Lv Tang, Tianyi Zheng, Yang Liu, Bo Li, Xingyu Li

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Visual text compression (VTC) promises efficient long-context processing by rendering text into an image and re-encoding it with a vision-language model, often producing $3$--$20\times$ fewer decoder tokens than subword tokenization. Yet token savings do not translate predictably into downstream utility: on some tasks the visual path matches or exceeds the text path, on others it collapses, and the compression ratio itself does not predict which regime will occur. The missing quantity is therefore not another summary of efficiency, but a principled measure of task-relevant information loss induced by visual encoding. We address this problem by formulating VTC in the language of measure transport. Treating text and visual tokens as empirical probability measures, we show that the ViT patch encoder induces a push-forward map whose transport cost decomposes into a precision cost from within-patch aggregation and a coverage cost from cross-patch fragmentation. Both terms are estimable from downstream-label-free probes. This formulation yields two operational consequences: a downstream-label-free routing criterion that selects whether to use the visual path for a given input or benchmark instance, and a transport-informed foveation mechanism that re-encodes high-cost regions at higher resolution. Across $24$ NLP datasets at Qwen3-4B, our label-free rule matches the per-dataset oracle on $17/24$ datasets ($70.8\%$), and improves the average task score by $+3.3\%$ with $-10.3\%$ average tokens relative to a pure-LLM.

Poster
VisInteract: Towards Dynamic Interactive Text-to-Visualization under Imperfect Queries

Wenxin Xu, Jinwei Lu, Hwanhee Kim, Chen J Zhang, Xiao-yong Wei, Haoyang Li, Yuanfeng Song

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Real-world visualization requests are routinely ambiguous, incomplete, or factually incorrect, yet existing Text-to-Visualization (Text-to-Vis) systems assume well-specified inputs and produce charts in a single pass. When queries are imperfect, a system must interact with the user to recover the true intent, but no benchmark or method supports this dynamic process. We introduce VisInteract, a new paradigm that reframes Text-to-Vis as interaction-driven intent recovery, and VisInteract-Bench, to our knowledge, that is the first benchmark for dynamic interactive Text-to-Vis, featuring controlled imperfection injection, a leakage-controlled User Agent for realistic multi-turn feedback, and dual-perspective (code and chart) automated evaluation. On the algorithmic side, we propose Vis-MCTS, a Monte Carlo Tree Search (MCTS) enhanced method, introducing improvements over classical MCTS, that Progressive Widening to tame the unbounded tool-argument space in tree search, cross-rollout information sharing so clarifications and critiques benefit the entire search tree, and Dimension-Aware Reward Decomposition that routes scalar user feedback along data-fidelity, visual-design, and intent-alignment dimensions to resolve credit assignment across heterogeneous actions. Extensive Experiments across two LLM backbones show that Vis-MCTS consistently outperforms all Text-to-Vis baselines, improving end-to-end task success by 13.40\%--16.27\% over the strongest interactive baseline and by more than 5\times over non-interactive ones.

Spotlight
View-Spectral Reconciliation Learning for Text-based Multispectral Aerial–Ground Person Re-Identification

Zhongao Zhou, Bin Yang, Yuxuan Zhao, Yudi Xie, Jun Chen, Mang Ye

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Conventional text-based person re-identification (ReID) approaches mainly rely on visible-spectrum images captured from ground-level viewpoints. However, with the increasing prevalence of UAVs and multispectral imaging systems, pedestrians can be captured from both ground and aerial viewpoints, and different spectral sensors provide complementary cues that reveal diverse pedestrian characteristics. As a result, conventional text-based ReID methods become inadequate for such retrieval scenarios. To address this limitation, we introduce a novel task termed Text-based Multispectral Aerial-Ground Person Re-Identification (TMAG-ReID), which aims to retrieve pedestrian images across aerial and ground viewpoints under multispectral scenarios using textual descriptions. To facilitate this task, we construct the T-MSAG dataset, which consists of multispectral pedestrian images captured from aerial and ground viewpoints, paired with corresponding textual descriptions. Furthermore, we propose a novel View-Spectral Reconciliation Learning framework (VSRL) that leverages textual guidance to interweave discriminative semantics across distinct views and spectral modalities. This fusion yields robust cross-view and cross-modal pedestrian features, thereby enabling high-performance retrieval. Extensive experiments on the T-MSAG dataset demonstrate the effectiveness of VSRL.

Poster
ViTeX-Bench: Benchmarking High-Fidelity Video Scene Text Editing

Xinghao Chen, Xiangbo Gao, Jiongze Yu, Yuheng Wu, Zhengzhong Tu

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Video scene text editing aims to replace text appearing on scene surfaces in a video, such as storefront signs, whiteboards, and product labels, while preserving the surrounding content, motion, and camera dynamics. Although scene text editing has been extensively studied for still images, its video counterpart remains underdeveloped. Existing resources do not provide paired edits over real-world videos, current protocols rarely measure whether the edited region reads as the target string over time, and there is no large-scale open-source benchmark for systematic comparison. To close these gaps, we introduce ViTeX-Bench, a comprehensive benchmark suite for high-fidelity and temporally consistent video scene text editing. Specifically, we first built ViTeX-Dataset, containing 387 real-world 720p videos with precise text-region masks and editing instructions; the 230-training split provides the first such resource with paired editing results built through a semi-automatic pipeline, with the rest forming the evaluation set for standardized benchmarking. In ViTeX-Bench, we propose a three-axis evaluation protocol: text correctness, visual quality, and edit locality, which contains a total of 13 metrics that combine character-level OCR signals with motion and preservation metrics. Our benchmarking experiments indicate that all eight leading video editing models, including both public and commercial models, fail in distinct ways: they either flicker or drift over time, or simply fail to produce the requested editing effects. To further validate the efficacy of our proposed dataset, we trained ViTeX-Edit-14B on the paired training split with a motion-aligned glyph-video conditioning stream. We show that, trained on only 230 high-quality paired videos, ViTeX-Edit-14B achieves the strongest CharAcc among video-native editors (0.688, +11.1\% over VideoPainter) and leads three ranked temporal metrics, reducing the previous best by 2.1\% (Flicker$_f$), 6.6\% (Flicker$_c$), and 1.9\% (Warp$_c$), respectively.

Poster
Uncovering Semantic Hierarchies in Text-Attributed Graphs via Variational EM-based LLM–GNN Synergy

Yunhui Liu, Xudong Jin, Qizhuo Xie, Chunhui Zhao, Xiao Luo, Tao Zheng, Bin Chong, Tieke He

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While hierarchical structures are intrinsic to organizing human knowledge, current representation learning on text-attributed graphs predominantly operates on flat semantic spaces, overlooking the rich coarse-to-fine granularity inherent in real-world data. To bridge this gap, we propose SHiFT, which synergizes the reasoning power of LLMs with the structural representation capability of GNNs within an Expectation-Maximization (EM) paradigm. In the E-step, we harness LLMs as expert taxonomists to induce an explicit semantic tree, introducing a lightweight Mapping \& Diagnosis strategy that reduces inference costs by surgically updating the hierarchy only when anomalies are detected. In the M-step, we align the GNN encoder with this induced hierarchy from complementary perspectives, including clustering partition, topological skeleton, and semantic concepts. Theoretical analysis interprets SHiFT as a generalized Variational EM algorithm. Extensive experiments demonstrate that SHiFT not only achieves state-of-the-art performance but also uncovers high-quality, human-readable taxonomies.

Poster
TriBet: Relative E-values for Online Machine-generated Text Detection

Xunye Tian, Zhijian Zhou, Liuhua Peng, Jared Collette, Dino Sejdinovic, Yue Yang, Feng Liu

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To ensure a formal guarantee that fully human-written text streams are *not falsely accused* as machine-generated text (MGT), the online betting framework (e-values) has been successfully applied on various existing detectors. However, current two-sample e-value methods fail in two real-world application scenarios: the false positive rate (FPR) is often out of control and the test power drops drastically when (1) the reference domain is similar but not exactly same as test domain (cross-domain), or (2) proxy model of detector is outdated compared to the modern source model. We identify the root cause as an online calibration dilemma: two-sample optimization and betting relies on a null-calibrating offset that is unidentifiable from unlabeled test streams under shift. We resolve this with a triple-sample betting framework (TriBet) that conduct online MGT detection as relative testing against both human and machine references using a witness score, and introduces a conformal test-inclusive domain-shift betting strategy to achieve FPR control without fragile online calibration. We show that TriBet is a level-$\alpha$ sequential test with asymptotic power one, and characterize its expected stopping time. Empirically, we evaluate on 15 source LLMs, 8 proxy models and mixed-document streams, TriBet consistently delivers faster and more powerful detection than both oracle and online betting baselines while keeping FPR strictly controlled.

Poster
Text-to-CAD Evaluation with CADTests

Dimitrios Mallis, Marco Wang, Ahmet Karadeniz, Elisa Ricci, Anis Kacem, Djamila Aouada

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Text-to-CAD has recently emerged as an important task with the potential to substantially accelerate design workflows. Despite its significance, there has been surprisingly little work on Text-to-CAD evaluation, and assessing CAD model generation performance remains a considerable challenge. In this work, we introduce a new evaluation perspective for Text-to-CAD based on automated testing. We propose CADTestBench, the first test-based benchmark for Text-to-CAD, based on CADTests, executable software tests that verify whether a generated CAD model satisfies the geometric and topological requirements of the input prompt. Using CADTestBench, we conduct comprehensive benchmarking of recent Text-to-CAD methods and further demonstrate that CADTests can also guide CAD model generation, yielding simple baselines that surpass performance of current methods. CADTestBench code and data are available at GitHub and Hugging Face dataset.

Poster
TROPT: An Open Framework for Unifying and Advancing Discrete Text Optimization

Matan Ben-Tov, Mahmood Sharif

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*Discrete text-trigger optimization*—searching for text sequences that, when ingested by a model, steer it toward a specified objective—underpins model red-teaming (e.g., LLM jailbreaks), as well as auditing and interpretability. However, the current state of discrete optimizers hinders their adoption and progress. First, existing optimizers, when open-sourced at all, are scattered across research codebases tied to specific problem domains. Second, optimizer variants proliferate, each requiring engineering overhead to use or extend, and hard to compare head-to-head. Together, these raise the bar to *adopting* optimizers in existing or new domains, and to *advancing* them via new strategies. We address these gaps with TROPT, the first open-source framework that unifies discrete optimizers' execution and standardizes their development under a single interface. TROPT currently ships with 30+ end-to-end optimization recipes—covering applications such as jailbreaking and probing model internals—built from 15+ optimizers (spanning white-box to black-box access) and 15+ losses, from foundational to state-of-the-art methods. Beyond democratizing established methods, TROPT makes it easy to *customize* optimization recipes by swapping any component—models, objectives, and optimizers—extending its reach across domains and new applications. Demonstrating its utility, we leverage TROPT in several controlled studies: *(i)* novel large-scale experiments comparing and enhancing optimization strategies for LLM jailbreaks, revealing potent-yet-underadopted techniques; and *(ii)* cross-domain demonstrations (e.g., benign prompt recovery and corpus poisoning). In all, TROPT significantly lowers the barrier to adopting and advancing discrete text optimization.

Poster
TRACE: Data-Free Text Reconstruction Attacks against Approximate Unlearning in LLMs

Mengying Zhang, Derui Wang, Ibrahim Khalil, Bowen Liu, Xiaoyu Xia, Minhui Xue

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As large language models (LLMs) face growing demands for data removal driven by regulatory compliance, copyright concerns, and privacy protection, approximate unlearning has emerged as a practical alternative to expensive full retraining. In practice, pre- and post-unlearning model snapshots are often maintained for auditing and rollback, introducing a previously overlooked side channel. This paper demonstrates that approximate unlearning in LLM can leave residual traces within model snapshots, which may be recoverable and thus enable the privacy breaches that approximate unlearning is intended to prevent. Here, we propose TRACE, a framework that reconstructs unlearned training data given access to pre- and post-unlearning model snapshots, without any data-specific prior knowledge. To achieve this, TRACE identifies a compact set of candidate tokens from embedding-level parameter differences to constrain the search space, and assembles sequences via a contrastive scoring mechanism based on the perplexity gap between the two models. A two-stage exploration-then-completion strategy enables the recovery of multiple distinct samples. Extensive experiments on various datasets, including TOFU, MUSE, and WMDP, across multiple LLMs and six representative unlearning methods, demonstrate that TRACE achieves high-fidelity reconstruction. This paper exposes significant privacy risks in current LLM approximate unlearning deployments and highlights the need for defenses against parameter-difference leakage and appropriate management of model snapshot access.

Poster
TED: Text-Axis Evidence Decomposition for Prompted Anomaly Localization

Jinyoung Kim, Geonho Kim, GiJeong Park, Geonu Lee, YoungJoon Yoo

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CLIP is a powerful vision-language model, but it was not designed for fine-grained defect localization; CLIP-based anomaly detectors therefore adapt it with prompts or lightweight modules to increase defect sensitivity. We show that stronger sensitivity does not necessarily make local evidence reliable: under domain shift, adapted CLIP-AD models often assign high anomaly scores to both true defects and visually complex normal regions. The issue is not simply missing defect information, but a local scoring rule that decodes defect and hard-normal evidence, having the same anomaly evidence. We propose \textsc{TED} (Text-Axis Evidence Decomposition), a post-hoc scoring method that asks whether each ambiguous response is better supported by source defect patches or by source normal patches mistaken as anomalous. \textsc{TED} compares these supports under the host's normal-versus-anomaly text response, leaves the backbone and prompts unchanged, and requires no target-domain training. It works as a train-free score for raw VLM backbones or as a source-calibrated residual correction for adapted CLIP-AD hosts. Across frozen VLM backbones, \textsc{TED} substantially improves pixel-level localization over raw prompt similarity; across adapted hosts, it improves most pixel-level settings over P-AUROC, P-PRO, and P-AP. Gains are largest under stronger hard-FP competition, with mean localization gain increasing from $+5.0$ in low-competition regimes to about $+10.9$ in mid/high-competition regimes. These results suggest that recoverable defect evidence can already exist in pretrained multimodal representations, but reliable localization requires decoding it against hard-normal competitors.

Poster
Speech Tokenizers are Vulnerable: Transferable Semantic Attack and Robust Tokenizer

Zhisheng Zhang, Yifan Mi, Yixuan Zhou, Haiyun Li, dongfu song, Shengbo Cai, Ziang Xu, Jie Hao, Zhiyong Wu

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Speech tokenizers serve as the critical interface between continuous speech signals and discrete representations, and are widely used in speech systems, e.g., Automatic Speech Recognition (ASR) and Large Audio-Language Models (LALMs). In this paper, we find that speech tokenizers are fragile at the semantic level: slight perturbations can disrupt their semantic encoding process and consequently cause severe degradation in downstream ASR and LALM performance. To study this vulnerability, we propose T-SemAttack, a transferable semantic attack based on a semantic encoder ensemble. By jointly perturbing the representation spaces of multiple semantic encoders, T-SemAttack effectively disrupts the semantic content of speech while preserving perceptual quality, thereby inducing error tokens. We further analyze token fragility and layer-wise representation drift in relation to cross-model transferability and disruption of LALM attention. Our analysis reveals a progressive amplification chain in which small waveform perturbations are magnified through the tokenizer pipeline and lead to semantic collapse, e.g., the attack causes a 99.7% token change in the S3 tokenizer. Building on these findings, we introduce ROSETok, a robust speech tokenizer that combines noisy training with robust semantic distillation to improve reconstruction fidelity and downstream-task robustness. Extensive experiments on multiple datasets, 9 open-source and black-box ASR systems, and 4 LALMs demonstrate that T-SemAttack achieves strong transferable attack performance, while the proposed Robust Speech Tokenizer exhibits robustness under high-fidelity reconstruction and downstream tasks. Our code and demo are available at https://t-semattack.github.io.

Poster
She Performs Your Voice: A Unified Speech and Dance Motion Model

Lurui Wang, Yongkang Cheng, Can Xu

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Expressive performers resonate with audiences because they transform sound into motion: rhythm invites steps, prosody evokes gestures, and energy shapes the flow of the body. However, existing audio-driven character systems often reduce audio to a task-specific condition, separately optimizing for co-speech gestures or music-driven dance. This fragmented view overlooks audio as the shared perceptual driver of performance, making it difficult to generate coherent full-body motion across speaking, dancing, and their intermediate states. We present VOXPERFORMER, a unified audio-to-motion framework that moves toward a generalized performance foundation model. Our key insight is that audio is not merely an external condition, but the hidden soul of performance style, governing how motion emerges, evolves, and transitions. To realize this, VOXPERFORMER introduces a structured motion prior to organize the full-body performance space, audio-to-prior distillation to transform sound into latent motion cues, a memory-augmented prior to resolve audio-motion ambiguity, and a decoupled diffusion generator with implicit transition matching for efficient and coherent synthesis. Experiments on BEAT2 and FineDance show that VOXPERFORMER remains competitive on speech-driven gesture generation while substantially improving hand-aware music-driven dance generation. User studies further show that participants prefer VOXPERFORMER, indicating stronger audio-motion correspondence and more natural perceptual resonance.

Poster
Seeing but Not Detecting: Privacy-Preserving Scene Text Attack via Hybrid Adversarial Policy Learning

Feiran Li, Jiahao Lyu, Ke Jiang, Yu Zhou, Jinqiao Shi

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Scene text encodes high-density semantic information, raising privacy risks for automated vision systems. Existing privacy-preserving adversarial methods mainly target Scene Text Recognition (STR) by inducing character-level misrecognition, yet text regions remain detectable, enabling manual inspection or downstream recovery. We argue that stronger privacy requires suppressing Scene Text Detection (STD) during localization, hiding text as background to bypass subsequent OCR pipelines. To this end, we propose **AR-Attacker** (**A**ttention-guided **R**einforcement learning text **Attacker**), a black-box attack framework that generates sparse, visually imperceptible perturbations to effectively suppress STD outputs. We formulate the attack as a Markov Decision Process (MDP) and design an attention-guided action space, which leverages a frozen surrogate model to focus perturbations on salient text regions. Furthermore, AR-Attacker employs a discrete-continuous hybrid policy optimized with Proximal Policy Optimization (PPO), which jointly selects perturbation locations and magnitudes. Empirical results show that AR-Attacker surpasses state-of-the-art baselines by 30% in text removal rate while simultaneously reducing query counts by 40%. Remarkably, the framework maintains high visual fidelity ($\textit{PSNR} > 45$ dB), advancing the "visible to humans, invisible to machines" privacy paradigm through a robust RL-based approach.

Poster
Seeing Speech: Learning Visible Articulatory Dynamics for Speech-Driven 3D Facial Animation

Hyung Kyu Kim, Byungchan Hwang, HAKGU KIM

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Recent progress in speech-driven 3D facial animation has improved vertex level reconstruction quality, but speech-consistent visible articulation remains difficult. This is because speech production follows structured and constrained lip jaw coordination and the mapping from acoustics to motion is inherently one to many. Motivated by the structured patterns of visible articulation, we propose a novel articulation-aware framework that models visible speech through directional lip motions and composes them into geometry consistent facial deformation. To represent visible articulation with three canonical directional motions, spreading, opening, and protrusion, we propose a Speech Articulatory Memory (SAM) that captures the correspondence between speech and directional articulatory motions under phonetic context through key-value memory structure based retrieval and decoding. Then, a Topology-aware Articulatory Composition (TAC) integrates the predicted directional motions under mesh topology to produce coherent 3D facial motion. Experiments on VOCASET and TFHP show that our method achieves the-state-of-the-art performance on standard reconstruction metrics and improves visible articulatory distance and velocity fidelity for key lip factors, while a user study confirms clear preference in lip sync and realism.

Poster
Say the Same, Act Differently: Text-Orthogonal Action Subspaces in Reasoning Vision-Language-Action Models

Zihao Feng, Qingzhao Zhang, Chunyu Xia, Bo Yu, Zhuoqing Morley Mao, Ramesh Govindan

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Vision-language-action (VLA) policies increasingly generate natural-language rationales before executing embodied actions. These rationales are attractive as monitors for safety-critical behavior because users or automated checkers can inspect whether the model appears to understand the scene and intend a safe action before execution. We show that this signal can be misleading. In many reasoning VLAs, the rationale generator and action head share continuous hidden states, while the generated text reveals only part of that representation. This creates a Say the Same, Act Differently failure mode, where rationale text remains stable while the action output changes substantially. We first study this phenomenon by introducing a new statistical method to separate text-sensitive and action-sensitive directions in hidden-state space of a reasoning VLA. Across the driving VLA Alpamayo and the manipulation VLA InstructVLA, we show that the dominant action direction lies largely outside the active text span, with mean projection ratios of only 1.9% and 5.3%. We define the residual as a text-neutral action-subspace (TNAS) direction, which tests whether action-relevant directions remain after removing measured text-sensitive directions. We then use TNAS to guide white-box pixel-space projected-gradient-descent (PGD) attacks on Alpamayo. TNAS-guided PGD successfully uses a localized two-forward-camera patch to induce a 30.5 m mean ADE shift in trajectory planning while preserving the exact rationale in 86.7% of cases. Moreover, across multiple text-preserving PGD objectives, the optimization direction consistently aligns with TNAS. These results reveal a fundamental shared-cache monitorability gap in reasoning VLAs: stable rationale text should not be treated as sufficient evidence that the action output remains stable.

Poster
SMASH: Probing Speech Recognition Robustness via Semantically Targeted Bit Flips

Zafaryab Haider, Md Hafizur Rahman, Aysegul Bumin, Prabuddha Chakraborty

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Automatic speech recognition (ASR) systems are usually judged by aggregate transcript accuracy, but real failures often hinge on meaning: for example, a wrong dose, address, account number, or date can matter more than many harmless word errors. We introduce SMASH, a framework for finding targeted semantic failures caused by sparse INT8 weight-bit perturbations, a dominant model data type for ASR edge devices, in quantized sequence-to-sequence ASR models. Given an audio input and a meaning-critical span,SMASH searches for small weight changes that replace the intended meaning while keeping the transcript readable, plausible, and close to the original output. Each accepted fault is a certificate that a specific semantic substitution is reachable under a bounded perturbation budget. Empirical study focuses on numeric and scalar substitutions across three ASR backbones: Whisper-small.en (WS), Whisper-large-v3 (WLv3), and SeamlessM4T-v2-large (S-M4T); and three corpora: an LLM-assisted controlled corpus (LACC), MultiMed, and LibriSpeech. On LACC at a 20-bit budget ($B$), SMASH-hybrid accepts numeric substitutions on 24/45 WS targets, 19/44 WLv3 targets, and 5/34 S-M4T targets; reachability is lower on real-speech datasets. In matched LACC budget sweeps tested up to $B=40$, WS reaches its ceiling already at $B=20$, while WLv3 and S-M4T continue to gain accepted targeted substitutions through $B=40$. Human validation supports the gate-based labels: on a 105-item shared validation set, independent human-majority labels and a four-judge large- language-model ensemble agree on the composite clean_success label, with $\kappa=1.00$. The faults are sparse: the pooled median is three INT8 bit flips, with medians of two flips on WS, eleven on WLv3, and twelve on S-M4T. Entity and negation pivots are evaluated as secondary evidence in the appendix. SMASH shifts ASR robustness evaluation from "how much did the transcript change?'' to "which meanings can be changed, how plausibly, and with how few bit flips?''

Poster
SENSE: Semantic Neural Speech Synthesis from Brain Dynamics via Spatial Graph Encoding

Jisoo Park, Seonghak Lee, Hyojin Park, Junseok Kwon

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Reconstructing speech from non-invasive brain signals offers a promising pathway for restoring communication in individuals who are cognitively intact but unable to speak. Existing EEG-to-speech approaches formulate this task as \emph{acoustic reconstruction}, optimizing waveform fidelity while ignoring whether the generated speech preserves high-level semantic content. In this work, we revisit this formulation and argue that EEG signals carry not only acoustic but also semantic information. We identify two key limitations of prior methods: (1) the neglect of spatial relationships between EEG electrodes, and (2) the failure to exploit the semantic structure of the N400 paradigm, where congruent and incongruent trials reflect distinct semantic processing. We propose \textbf{SENSE} (\textbf{S}emantic-\textbf{E}EG \textbf{N}eural \textbf{S}peech Synth\textbf{E}sis), which combines a graph-based EEG encoder over electrode geometry with EEG Semantic Conditioning (ESC), aligning EEG to a pretrained semantic space using only congruent trials. On the N400 dataset, SENSE consistently outperforms prior methods on both acoustic and semantic metrics, and model-internal channel attribution suggests distributed reliance on auditory, sensorimotor, and centro-parietal regions, consistent with known speech-perception neuroscience. In the unseen-subject setting, SENSE trained on only two subjects already surpasses the strongest baseline trained on all eighteen subjects in word error rate, and matches it on acoustic metrics with as few as eight subjects.

Poster