Emotion recognition based on multimodal physiological signals is playing an increasingly important role in areas such as human-computer interaction and disease diagnosis, attracting growing attention from the research community. Current studies primarily focus on emotion recognition under unified data collection paradigms, overlooking the prevalent issue of imperfect modality matching in real-world scenarios. In particular, existing methods fail to effectively utilize these mismatched modalities, leading to incomplete emotional representations. This limits the model's ability to accurately capture the multidimensional semantic features of emotions, thereby constraining its effectiveness and applicability in practical settings. To address this challenge, we propose MoCERNet. At the modality level, it first reduces the domain gap among matched modalities and then aligns mismatched modalities in a semantics-aware manner, guided by the matched ones. At the decision level, it further mitigates the global distribution discrepancies to achieve a more complete emotional representation. In addition, we design a Nervous System Functional Structure Transformer (NFSformer) that enables the model to focus on the correlation between different brain regions and peripheral physiological signals under various emotional states, thereby enhancing its capacity to model complex emotional processes. Experiments on three multimodal emotion datasets demonstrate that MoCERNet outperforms state-of-the-art baselines under imperfect modality matching scenarios.

Medical time-series analysis differs fundamentally from general ones by requiring specialized domain knowledge to interpret complex signals and clinical context. Large language models (LLMs) hold great promise for augmenting medical time-series analysis by complementing raw series with rich contextual knowledge drawn from biomedical literature and clinical guidelines. However, realizing this potential depends on precise and meaningful prompts that guide the LLM to key information. Yet, determining what constitutes effective prompt content remains non-trivial—especially in medical settings where signal interpretation often hinges on subtle, expert-defined decision-making indicators. To this end, we propose InDiGO, a knowledge-aware evolutionary learning framework that integrates clinical signals and decision-making indicators through iterative optimization. Across four medical benchmarks, InDiGO consistently outperforms prior methods. The code is available at: https://github.com/jinxyBJTU/InDiGO.

Affective brain-computer interfaces (aBCIs) play a crucial role in personalized human–computer interaction and neurofeedback modulation. To develop practical and effective aBCI paradigms and to investigate the spatial-temporal dynamics of brain activity under emotional inducement, portable electroencephalography (EEG) signals have been widely adopted. To further enhance spatial-temporal perception, functional near-infrared spectroscopy (fNIRS) has attracted increasing interest in the aBCI field and has been explored in combination with EEG. However, existing datasets typically provide only static fixation labels, overlooking the dynamic changes in subjects' emotions. Notably, some studies have attempted to collect continuously annotated emotional data, but they have recorded only peripheral physiological signals without directly observing brain activity, limiting insight into underlying neural states under different emotions. To address these challenges, we present the Real-time labeled EEG-fNIRS Dataset (REFED). To the best of our knowledge, this is the first EEG-fNIRS dataset with real-time dynamic emotional annotations. REFED simultaneously records brain signals from both EEG and fNIRS modalities while providing continuous, real-time annotations of valence and arousal. The results of the data analysis demonstrate the effectiveness of emotion inducement and the reliability of real-time annotation. This dataset offers the possibility for studying the neurovascular coupling mechanism under emotional evolution and for developing dynamic, robust affective BCIs.

The study of the relationship between emotions and physiological signals of subjects under multimedia stimulation is an emerging field, and many important advances are made. However, there are still some challenges: 1) How to effectively utilize the complementarity among spatial-spectral-temporal domain information. 2) How to employ the heterogeneity and the correlation among multi-modal physiological signals simultaneously. 3) How to improve the robustness of the model dealing with missing channels. 4) How to model the dependency among different emotions. In this paper, we propose a novel two-stream Dynamic Heterogeneous Graph Recurrent Neural Network called DHGRNN. Specifically, DHGRNN consists of a spatial-temporal stream, a spatial-spectral stream, a fusion layer, and a multi-label classifier. Each stream is composed of a graph transformer network, evolved graph convolutional neural network, and gated recurrent units. We propose a graph-based two-stream structure to fuse the information of the spatial-spectral-temporal domain simultaneously. Graph transformer network and evolved graph convolutional neural network are used to model the heterogeneity and correlation of multi-modal physiological signals, respectively. To deal with the problem of robustness in the face of missing channel data, we transform it into the problem of dynamic graphs and use a dynamic graph neural network to improve the robustness. In addition, we propose a multi-label classifier to model the dependency among different emotion dimensions. Experiments on three public datasets demonstrate that our proposed model outperforms existing state-of-the-art methods.

Sleep stage classification is an important step in the diagnosis and treatment of sleep disorders. Despite the high classification performance of previous sleep stage classification work, some challenges remain unresolved: 1) How to effectively capture salient waves in sleep signals to improve sleep stage classification results. 2) How to capture salient waves affected by inter-subject variability. 3) How to adaptively regulate the importance of different modals for different sleep stages. To address these challenges, we propose SleepWaveNet, a multimodal salient wave detection network, which is motivated by the salient object detection task in computer vision. It has a U-Transformer structure to detect salient waves in sleep signals. Meanwhile, the subject-adaptation wave extraction architecture based on transfer learning can adapt to the information of target individuals and extract salient waves with inter-subject variability. In addition, the multimodal attention module can adaptively enhance the importance of specific modal data for sleep stage classification tasks. Experiments on three datasets show that SleepWaveNet has better overall performance than existing baselines. Moreover, visualization experiments show that the model has the ability to capture salient waves with inter-subject variability.

With the deepening of neuroscience research, data mining of brain signals is becoming an emerging topic. Among various brain signals, electroencephalography (EEG) has attracted more and more attention due to its advantages of non-invasiveness, portability, and low cost. EEG modeling and analysis play a vital role in human healthcare. Although many machine learning algorithms have been successfully applied to data mining of EEG signals, few of them achieve a win-win in classification performance and interpretability. In this paper, we propose a Bayesian graph neural network named BayesEEGNet. Considering an electrical impulse between two nodes in the brain as a Poisson process, the countless electrical impulses generated by the brain in a period are represented as an infinite number of connection probability graphs. After coupling and transforming these probability graphs, we interpret the brain’s electrical activity state as the brain’s perceptual state. Benefiting from the joint optimization of Bayesian modules and deep neural networks, our model shows superior classification performance in sleep stage classification and emotion recognition tasks. Meanwhile, our model is able to learn interpretable functional connectivity relationships between EEG channels without any prior knowledge.

Contrastive learning has successfully addressed the scarcity of large-scale labeled datasets, especially in the physiological time series field. Existing methods construct easy positive pairs as substitutes for ground truth based on temporal dynamics or instance consistency. Despite the potential of hard positive samples to provide richer gradient information and facilitate the acquisition of more discriminative representations, they are frequently overlooked in sampling strategies, thus constraining the classification capacity of models. In this paper, we focus on multi-view physiological signals and propose a novel hard positive sampling strategy based on the view consistency. Multi-view signals are recorded from sensors attached to different organs of human body. Additionally, we propose a Multi-View Consistency Contrastive (MVCC) learning framework to jointly extract intra-view temporal dynamics and inter-view consistency features. Experiments have been carried out on two public datasets and our method demonstrates state-of-the-art performance, achieving 83.25% and 73.37% accuracy on SleepEDF and ISRUC, respectively.

Sleep stage classification is essential for sleep assessment and disease diagnosis. However, how to effectively utilize brain spatial features and transition information among sleep stages continues to be challenging. In particular, owing to the limited knowledge of the human brain, predefining a suitable spatial brain connection structure for sleep stage classification remains an open question. In this paper, we propose a novel deep graph neural network, named GraphSleepNet, for automatic sleep stage classification. The main advantage of the GraphSleepNet is to adaptively learn the intrinsic connection among different electroencephalogram (EEG) channels, represented by an adjacency matrix, thereby best serving the spatial-temporal graph convolution network (ST-GCN) for sleep stage classification. Meanwhile, the ST-GCN consists of graph convolutions for extracting spatial features and temporal convolutions for capturing the transition rules among sleep stages. Experiments on the Montreal Archive of Sleep Studies (MASS) dataset demonstrate that the GraphSleepNet outperforms the state-of-the-art baselines.