Decoding visual features from EEG signals is a central challenge in neuroscience, with cross-modal alignment as the dominant approach. We argue that the relationship between visual and brain modalities is fundamentally asymmetric, characterized by two critical gaps: a Fidelity Gap (stemming from EEG's inherent noise and signal degradation, vs. vision's high-fidelity features) and a Semantic Gap (arising from EEG's shallow conceptual representation, vs. vision's rich semantic depth). Previous methods often overlook this asymmetry, forcing alignment between the two modalities as if they were equal partners and thereby leading to poor generalization. To address this, we propose the adaptive teaching paradigm. This paradigm empowers the ``teacher" modality (vision) to dynamically shrink and adjust its knowledge structure under task guidance, tailoring its semantically dense features to match the ``student" modality (EEG)'s capacity. We implement this paradigm with the ShrinkAdapter, a simple yet effective module featuring a residual-free design and a bottleneck structure. Through extensive experiments, we validate the underlying rationale and effectiveness of our paradigm. Our method achieves a top-1 accuracy of 60.2% on the zero-shot brain-to-image retrieval task, surpassing previous state-of-the-art methods by a margin of 9.8%. Our work introduces a new perspective for asymmetric alignment: the teacher must shrink and adapt to bridge the vision-brain gap.

Electroencephalogram (EEG) signals have attracted significant attention from researchers due to their non-invasive nature and high temporal sensitivity in decoding visual stimuli. However, most recent studies have focused solely on the relationship between EEG and image data pairs, neglecting the valuable "beyond-image-modality" information embedded in EEG signals. This results in the loss of critical multimodal information in EEG. To address the limitation, this paper proposes a unified framework that fully leverages multimodal data to represent EEG signals, named CognitionCapturer. Specifically, CognitionCapturer trains modality expert encoders for each modality to extract cross-modal information from the EEG modality. Then, it introduces a diffusion prior to map the EEG embedding space to the CLIP embedding space, followed by using a pretrained generative model, the proposed framework can reconstruct visual stimuli with high semantic and structural fidelity. Notably, the framework does not require any fine-tuning of the generative models and can be extended to incorporate more modalities. Through extensive experiments, we demonstrate that CognitionCapturer outperforms state-of-the-art methods both qualitatively and quantitatively.

Multimodal sentiment analysis aims at exploiting complementary information from multiple modalities or data sources to enhance the understanding and interpretation of sentiment. While existing multi-modal fusion techniques offer significant improvements in sentiment analysis, real-world scenarios often involve missing modalities, introducing complexity due to uncertainty of which modalities may be absent. To tackle the challenge of incomplete modality-specific feature extraction caused by missing modalities, this paper proposes a Cosine Margin-Aware Network (CMANet) which centers on the Cosine Margin-Aware Distillation (CMAD) module. The core module measures distance between samples and the classification boundary, enabling CMANet to focus on samples near the boundary. So, it effectively captures the unique features of different modal combinations. To address the issue of modality imbalance during modality-specific feature extraction, this paper proposes a Weak Modality Regularization (WMR) strategy, which aligns the feature distributions between strong and weak modalities at the dataset-level, while also enhancing the prediction loss of samples at the sample-level. This dual mechanism improves the recognition robustness of weak modality combination. Extensive experiments demonstrate that the proposed method outperforms the previous best model, MMIN, with a 3.82% improvement in unweighted accuracy. These results underscore the robustness of the approach under conditions of uncertain and missing modalities.