REVIEW 1 major objections 1 minor 63 references
Generative Visual Grounding turns EEG signals into proxy images so MLLMs can apply visual priors to brain-state interpretation.
Reviewed by Pith at T0; open to challenge. T0 means a machine referee read the full paper against a public rubric. the ladder, T0–T4 →
T0 review · grok-4.3
2026-06-30 18:46 UTC pith:H3T5GARM
load-bearing objection GVG shows EEG-to-image proxies can match text alignment with far less tuning, but the claim that these proxies actually ground non-visual signals rests on untested assumptions. the 1 major comments →
Visualizing the Invisible: Generative Visual Grounding Empowers Universal EEG Understanding in MLLMs
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
GVG hallucinates instance-specific proxy images for non-visual EEG, providing structured visual contexts that allow MLLMs to exploit their visual priors for clinical-state interpretation.
What carries the argument
Generative Visual Grounding (GVG) framework, which employs an EEG-to-image generative model as a visual translator to create proxy images.
Load-bearing premise
An EEG-to-image generative model can accurately capture and translate fine-grained perceptual information encoded in brain activity into useful visual proxies without significant loss or distortion.
What would settle it
A test in which replacing the generated proxy images with either text-only inputs or random images produces no measurable drop in EEG classification or generation accuracy on the same MLLM backbones would falsify the claimed benefit.
If this is right
- Image-only alignment matches 1.7B-parameter text-aligned baselines while tuning only 170M parameters on a frozen 7B backbone.
- Trimodal Image+Text alignment improves performance by letting text supply categorical anchors while visual proxies add perceptual detail.
- The approach yields consistent gains on both EEG understanding and visual generation tasks.
Where Pith is reading between the lines
- The method could be tested on other non-visual sensor streams such as EMG or EOG to check whether visual proxy grounding generalizes beyond EEG.
- If the proxies preserve diagnostic features, they might serve as human-readable visualizations for clinicians reviewing model outputs.
- The framework raises the question of whether the quality of the EEG-to-image generator itself becomes the new performance bottleneck once the MLLM backbone is held fixed.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper proposes Generative Visual Grounding (GVG), a framework that uses an EEG-to-image generative model to produce instance-specific proxy images from non-visual EEG signals. These visual proxies are intended to supply structured contexts that allow MLLMs to exploit visual priors for clinical-state interpretation, complementing text-based alignment. The approach is evaluated on two MLLM backbones (GVG-X-Omni and GVG-Janus), with claims of competitive performance using only 170M tunable parameters on a frozen 7B backbone and further gains from trimodal (Image+Text) alignment.
Significance. If the EEG-to-image translation faithfully preserves perceptual details from brain activity, the method could meaningfully advance multimodal brain foundation models by enriching neural representations beyond lossy text alignment. The reported parameter efficiency and consistent experimental gains represent practical strengths that would be of interest if substantiated.
major comments (1)
- [Abstract] Abstract: The central claim that GVG 'hallucinates instance-specific proxy images' providing 'structured visual contexts' for 'fine-grained perceptual information' rests on the unverified assumption that an EEG-to-image generator can accurately translate non-visual EEG without significant distortion or reliance on its own priors. No conditioning details, fidelity metrics, or ablations against non-EEG-conditioned images are described, leaving open the possibility that downstream MLLM gains arise from generic visual augmentation rather than EEG-specific grounding.
minor comments (1)
- [Abstract] Abstract: The phrasing 'visually-evoked EEG datasets remain scarce' could be clarified with a brief citation or quantification to support the motivation for shifting away from text-only alignment.
Simulated Author's Rebuttal
We thank the referee for the constructive feedback emphasizing the need to substantiate the EEG-to-image translation. We address the comment below and will revise the manuscript to incorporate the suggested clarifications and experiments.
read point-by-point responses
-
Referee: [Abstract] Abstract: The central claim that GVG 'hallucinates instance-specific proxy images' providing 'structured visual contexts' for 'fine-grained perceptual information' rests on the unverified assumption that an EEG-to-image generator can accurately translate non-visual EEG without significant distortion or reliance on its own priors. No conditioning details, fidelity metrics, or ablations against non-EEG-conditioned images are described, leaving open the possibility that downstream MLLM gains arise from generic visual augmentation rather than EEG-specific grounding.
Authors: We agree that the abstract does not detail these elements and that the full manuscript would benefit from explicit verification to rule out generic visual effects. The methods section describes the EEG conditioning via a dedicated encoder, but to directly address the concern we will add: (1) expanded conditioning details with architecture diagrams, (2) fidelity metrics (FID, perceptual similarity) on available visually-evoked EEG subsets, and (3) an ablation comparing EEG-conditioned proxies against non-EEG (random or text-only) image inputs in the MLLM downstream tasks. These additions will be included in the revised version to demonstrate EEG-specific contributions. revision: yes
Circularity Check
No circularity: methodological proposal without derivations or self-referential reductions
full rationale
The paper introduces Generative Visual Grounding (GVG) as a framework that uses an EEG-to-image model to generate proxy images for alignment with MLLMs. No equations, first-principles derivations, or predictive claims appear in the abstract or described structure. The central idea is a proposed architecture (EEG-to-image translator plus multimodal alignment) whose value is asserted via experimental gains rather than any reduction to fitted parameters or prior self-citations. No self-definitional loops, fitted-input predictions, or uniqueness theorems are invoked. The work is therefore self-contained as an empirical method proposal.
Axiom & Free-Parameter Ledger
read the original abstract
Leveraging the universal representations of pre-trained LLMs and MLLMs offers a promising path toward brain foundation models. However, visually-evoked EEG datasets remain scarce, leading existing methods to align neural signals mainly with abstract text, a lossy translation that may discard fine-grained perceptual information encoded in brain activity. We propose Generative Visual Grounding (GVG), a framework that visualizes the invisible by using an EEG-to-image generative model as a visual translator. Instead of forcing EEG into text alone, GVG hallucinates instance-specific proxy images for non-visual EEG, providing structured visual contexts that allow MLLMs to exploit their visual priors for clinical-state interpretation. We validate this idea on two MLLM backbones, GVG-X-Omni and GVG-Janus. Image-only alignment is already competitive: the lightweight GVG-X-Omni matches 1.7B-parameter text-aligned baselines while tuning only 170M parameters on a frozen 7B backbone. We further extend GVG-Janus with trimodal Image+Text alignment, where text supplies categorical semantic anchors and visual proxies enrich neural representations with perceptual details. Experiments show consistent gains in EEG understanding and visual generation, suggesting visual proxy grounding as an effective complement to textual alignment.
Figures
Reference graph
Works this paper leans on
-
[1]
Josh Achiam, Steven Adler, Sandhini Agarwal, Lama Ahmad, Ilge Akkaya, Floren- cia Leoni Aleman, Diogo Almeida, Janko Altenschmidt, Sam Altman, Shyamal Anadkat, et al. 2023. Gpt-4 technical report.arXiv preprint arXiv:2303.08774 (2023)
work page internal anchor Pith review Pith/arXiv arXiv 2023
-
[2]
Diego Alvarez-Estevez and Roselyne M Rijsman. 2021. Inter-database validation of a deep learning approach for automatic sleep scoring.PloS one16, 8 (2021), e0256111
2021
-
[3]
Yunpeng Bai, Xintao Wang, Yan-pei Cao, Yixiao Ge, Chun Yuan, and Ying Shan
-
[4]
Dreamdiffusion: Generating high-quality images from brain eeg signals. arXiv preprint arXiv:2306.16934(2023)
- [5]
-
[6]
Donghong Cai, Junru Chen, Yang Yang, Teng Liu, and Yafeng Li. 2023. Mbrain: A multi-channel self-supervised learning framework for brain signals. InPro- ceedings of the 29th ACM SIGKDD Conference on Knowledge Discovery and Data Mining. 130–141
2023
-
[7]
Josue Ortega Caro, Antonio H de O Fonseca, Christopher Averill, Syed A Rizvi, Matteo Rosati, James L Cross, Prateek Mittal, Emanuele Zappala, Daniel Levine, Rahul M Dhodapkar, et al. 2023. BrainLM: A foundation model for brain activity recordings.bioRxiv(2023), 2023–09
2023
-
[8]
Xuhang Chen, Baiying Lei, Chi-Man Pun, and Shuqiang Wang. 2023. Brain diffuser: An end-to-end brain image to brain network pipeline. InChinese Con- ference on Pattern Recognition and Computer Vision (PRCV). Springer, 16–26
2023
-
[9]
Zijiao Chen, Jiaxin Qing, and Juan Helen Zhou. 2023. Cinematic mindscapes: High-quality video reconstruction from brain activity.Advances in Neural Infor- mation Processing Systems36 (2023), 24841–24858
2023
- [10]
-
[11]
Wenhui Cui, Woojae Jeong, Philipp Thölke, Takfarinas Medani, Karim Jerbi, Anand A Joshi, and Richard M Leahy. 2024. Neuro-gpt: Towards a foundation model for eeg. In2024 IEEE International Symposium on Biomedical Imaging (ISBI). IEEE, 1–5
2024
- [12]
- [13]
-
[14]
Ruo-Nan Duan, Jia-Yi Zhu, and Bao-Liang Lu. 2013. Differential entropy feature for EEG-based emotion classification. In6th International IEEE/EMBS Conference on Neural Engineering (NER). IEEE, 81–84
2013
- [15]
- [16]
-
[17]
Amir Harati, Meysam Golmohammadi, Silvia Lopez, Iyad Obeid, and Joseph Picone. 2015. Improved EEG event classification using differential energy. In 2015 IEEE Signal Processing in Medicine and Biology Symposium (SPMB). IEEE, 1–4
2015
-
[18]
Shuai Huang, Yongxiong Wang, Huan Luo, Haodong Jing, Chendong Qin, and Jingqun Tang. 2025. MINDEV: Multi-modal Integrated Diffusion Framework for Video Reconstruction from EEG Signals. InProceedings of the 33rd ACM International Conference on Multimedia. 3350–3359
2025
-
[19]
Minyoung Huh, Brian Cheung, Tongzhou Wang, and Phillip Isola. 2024. The platonic representation hypothesis.arXiv preprint arXiv:2405.07987(2024)
work page internal anchor Pith review Pith/arXiv arXiv 2024
-
[20]
Wei-Bang Jiang, Xuan-Hao Liu, Wei-Long Zheng, and Bao-Liang Lu. 2025. SEED- VII: A Multimodal Dataset of Six Basic Emotions With Continuous Labels for Emotion Recognition.IEEE Transactions on Affective Computing16, 2 (2025), 969–985. doi:10.1109/TAFFC.2024.3485057
- [21]
- [22]
-
[23]
Jin Jing, Wendong Ge, Shenda Hong, Marta Bento Fernandes, Zhen Lin, Chaoqi Yang, Sungtae An, Aaron F Struck, Aline Herlopian, Ioannis Karakis, et al. 2023. Development of expert-level classification of seizures and rhythmic and periodic patterns during EEG interpretation.Neurology100, 17 (2023), e1750–e1762
2023
-
[24]
Isaak Kavasidis, Simone Palazzo, Concetto Spampinato, Daniela Giordano, and Mubarak Shah. 2017. Brain2image: Converting brain signals into images. In Proceedings of the 25th ACM international conference on Multimedia. 1809–1817
2017
- [25]
-
[26]
Demetres Kostas, Stephane Aroca-Ouellette, and Frank Rudzicz. 2021. BENDR: Using transformers and a contrastive self-supervised learning task to learn from massive amounts of EEG data.Frontiers in Human Neuroscience15 (2021), 653659
2021
-
[27]
Black Forest Labs, Stephen Batifol, Andreas Blattmann, Frederic Boesel, Saksham Consul, Cyril Diagne, Tim Dockhorn, Jack English, Zion English, Patrick Esser, Sumith Kulal, Kyle Lacey, Yam Levi, Cheng Li, Dominik Lorenz, Jonas Müller, Dustin Podell, Robin Rombach, Harry Saini, Axel Sauer, and Luke Smith. 2025. FLUX.1 Kontext: Flow Matching for In-Context ...
work page internal anchor Pith review Pith/arXiv arXiv 2025
- [28]
-
[29]
Hongli Li, Man Ding, Ronghua Zhang, and Chunbo Xiu. 2022. Motor imagery EEG classification algorithm based on CNN-LSTM feature fusion network.Biomedical signal processing and control72 (2022), 103342
2022
- [30]
-
[31]
Haotian Liu, Chunyuan Li, Qingyang Wu, and Yong Jae Lee. 2023. Visual in- struction tuning.Advances in neural information processing systems36 (2023), 34892–34916
2023
-
[32]
Xuan-Hao Liu, Yan-Kai Liu, Yansen Wang, Kan Ren, Hanwen Shi, Zilong Wang, Dongsheng Li, Bao-Liang Lu, and Wei-Long Zheng. 2024. EEG2video: Towards decoding dynamic visual perception from EEG signals.Advances in Neural Information Processing Systems37 (2024), 72245–72273
2024
-
[33]
Xuan-Hao Liu, Bao-Liang Lu, and Wei-Long Zheng. 2025. Eegmirror: Leveraging eeg data in the wild via montage-agnostic self-supervision for eeg to video decoding. InProceedings of the IEEE/CVF International Conference on Computer Vision. 18273–18283
2025
-
[34]
Weiheng Lu, Chunfeng Song, Jiamin Wu, Pengyu Zhu, Yuchen Zhou, Weijian Mai, Qihao Zheng, and Wanli Ouyang. 2025. UniMind: Unleashing the Power of LLMs for Unified Multi-Task Brain Decoding.arXiv preprint arXiv:2506.18962 (2025)
work page internal anchor Pith review Pith/arXiv arXiv 2025
-
[35]
Fei Ma, Han Lin, Yifan Xie, Hongwei Ren, Xiaoyu Shen, Wenbo Ding, and Qi Tian
-
[36]
arXiv preprint arXiv:2601.07877(2026)
Eˆ 2-LLM: Bridging Neural Signals and Interpretable Affective Analysis. arXiv preprint arXiv:2601.07877(2026)
-
[37]
Wei Yan Peh, Yuanyuan Yao, and Justin Dauwels. 2022. Transformer convolu- tional neural networks for automated artifact detection in scalp EEG. In2022 44th Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC). IEEE, 3599–3602
2022
-
[38]
Alec Radford, Jong Wook Kim, Chris Hallacy, Aditya Ramesh, Gabriel Goh, Sand- hini Agarwal, Girish Sastry, Amanda Askell, Pamela Mishkin, Jack Clark, et al
-
[39]
In International conference on machine learning
Learning transferable visual models from natural language supervision. In International conference on machine learning. PmLR, 8748–8763
- [40]
-
[41]
Concetto Spampinato, Simone Palazzo, Isaak Kavasidis, Daniela Giordano, Nasim Souly, and Mubarak Shah. 2017. Deep learning human mind for automated visual classification. InProceedings of the IEEE conference on computer vision and pattern recognition. 6809–6817
2017
-
[42]
Gemini Team, Rohan Anil, Sebastian Borgeaud, Jean-Baptiste Alayrac, Jiahui Yu, Radu Soricut, Johan Schalkwyk, Andrew M Dai, Anja Hauth, Katie Millican, et al. 2023. Gemini: a family of highly capable multimodal models.arXiv preprint arXiv:2312.11805(2023)
work page internal anchor Pith review Pith/arXiv arXiv 2023
-
[43]
Keyu Tian, Yi Jiang, Zehuan Yuan, Bingyue Peng, and Liwei Wang. 2024. Visual autoregressive modeling: Scalable image generation via next-scale prediction. Advances in neural information processing systems37 (2024), 84839–84865
2024
-
[44]
Michael Tschannen, Alexey Gritsenko, Xiao Wang, Muhammad Ferjad Naeem, Ibrahim Alabdulmohsin, Nikhil Parthasarathy, Talfan Evans, Lucas Beyer, Ye Xia, Basil Mustafa, et al. 2025. Siglip 2: Multilingual vision-language encoders with improved semantic understanding, localization, and dense features.arXiv preprint arXiv:2502.14786(2025)
work page internal anchor Pith review Pith/arXiv arXiv 2025
- [45]
-
[46]
Guangyu Wang, Wenchao Liu, Yuhong He, Cong Xu, Lin Ma, and Haifeng Li
-
[47]
9 Pan et al
Eegpt: Pretrained transformer for universal and reliable representation of eeg signals.Advances in Neural Information Processing Systems37 (2024), 39249–39280. 9 Pan et al
2024
- [48]
-
[49]
Peng Wang, Shuai Bai, Sinan Tan, Shijie Wang, Zhihao Fan, Jinze Bai, Keqin Chen, Xuejing Liu, Jialin Wang, Wenbin Ge, et al. 2024. Qwen2-vl: Enhancing vision-language model’s perception of the world at any resolution.arXiv preprint arXiv:2409.12191(2024)
work page internal anchor Pith review Pith/arXiv arXiv 2024
-
[50]
Chengyue Wu, Xiaokang Chen, Zhiyu Wu, Yiyang Ma, Xingchao Liu, Zizheng Pan, Wen Liu, Zhenda Xie, Xingkai Yu, Chong Ruan, et al. 2024. Janus: Decoupling visual encoding for unified multimodal understanding and generation.arXiv preprint arXiv:2410.13848(2024)
work page internal anchor Pith review Pith/arXiv arXiv 2024
-
[51]
An Yang, Baosong Yang, Binyuan Hui, Bo Zheng, Bowen Yu, Chang Zhou, Cheng- peng Li, Chengyuan Li, Dayiheng Liu, Fei Huang, Guanting Dong, Haoran Wei, Huan Lin, Jialong Tang, Jialin Wang, Jian Yang, Jianhong Tu, Jianwei Zhang, Jianxin Ma, Jin Xu, Jingren Zhou, Jinze Bai, Jinzheng He, Junyang Lin, Kai Dang, Keming Lu, Keqin Chen, Kexin Yang, Mei Li, Mingfen...
work page internal anchor Pith review Pith/arXiv arXiv 2024
-
[52]
Chaoqi Yang, M Westover, and Jimeng Sun. 2023. Biot: Biosignal transformer for cross-data learning in the wild.Advances in Neural Information Processing Systems36 (2023), 78240–78260
2023
-
[53]
Chaoqi Yang, Cao Xiao, M Brandon Westover, and Jimeng Sun. 2023. Self- supervised electroencephalogram representation learning for automatic sleep staging: model development and evaluation study.JMIR AI2, 1 (2023), e46769
2023
- [54]
-
[55]
Ke Yi, Yansen Wang, Kan Ren, and Dongsheng Li. 2023. Learning topology- agnostic EEG representations with geometry-aware modeling.Advances in Neural Information Processing Systems36 (2023), 53875–53891
2023
-
[56]
Zhizhang Yuan, Fanqi Shen, Meng Li, Yuguo Yu, Chenhao Tan, and Yang Yang
- [57]
- [58]
-
[59]
Xiaohua Zhai, Basil Mustafa, Alexander Kolesnikov, and Lucas Beyer. 2023. Sigmoid loss for language image pre-training. InProceedings of the IEEE/CVF international conference on computer vision. 11975–11986
2023
-
[60]
Daoze Zhang, Zhizhang Yuan, Yang Yang, Junru Chen, Jingjing Wang, and Yafeng Li. 2023. Brant: Foundation model for intracranial neural signal.Advances in Neural Information Processing Systems36 (2023), 26304–26321
2023
-
[61]
Xiang Zhang, Ziyuan Zhao, Theodoros Tsiligkaridis, and Marinka Zitnik. 2022. Self-supervised contrastive pre-training for time series via time-frequency con- sistency.Advances in neural information processing systems35 (2022), 3988–4003
2022
-
[62]
W. Zheng, W. Liu, Y. Lu, B. Lu, and A. Cichocki. 2018. EmotionMeter: A Mul- timodal Framework for Recognizing Human Emotions.IEEE Transactions on Cybernetics(2018), 1–13. doi:10.1109/TCYB.2018.2797176
-
[63]
Wei-Long Zheng and Bao-Liang Lu. 2015. Investigating Critical Frequency Bands and Channels for EEG-based Emotion Recognition with Deep Neural Networks.IEEE Transactions on Autonomous Mental Development7, 3 (2015), 162–175. doi:10.1109/TAMD.2015.2431497 10
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.