References#

This page provides an overview of the foundational literature behind SPD Learn, organized by model architecture and research lineage.

Literature Map#

The following visualization shows the relationships between key publications implemented in SPD Learn. The map illustrates how different SPD neural network architectures have evolved and influenced each other over time.

Literature map showing connections between SPD Learn model papers

SPD Learn Literature Map — Generated with Litmaps. The x-axis represents publication date (more recent to the right), and the y-axis represents citation count (more cited at the top). Lines show citation relationships between papers.#


Model Legend#

The following legend explains the color coding used in the literature map above, with each color representing a distinct model family implemented in SPD Learn.

SPDNet
The foundational architecture for deep learning on SPD manifolds using BiMap, ReEig, and LogEig layers. Originally developed for computer vision tasks; application to EEG/neuroimaging is original work by the BCI research community.
Huang & Van Gool, 2017
Riemannian BatchNorm
Riemannian batch normalization technique for SPD neural networks, used in TSMNet and TensorCSPNet.
Brooks et al., 2019
TSMNet
Tangent Space Mapping Network combining temporal convolutions with SPD batch normalization for domain adaptation.
Kobler et al., 2022
MAtt
Manifold Attention Network integrating Riemannian geometry with attention mechanisms on SPD matrices.
Pan et al., 2022
TensorCSPNet
Multi-band SPDNet framework using tensor stacking and Common Spatial Patterns for filter bank EEG classification.
Ju et al., 2022
EEGSPDNet
End-to-end architecture with channel-specific convolution, covariance pooling, and SPDNet for EEG classification.
Wilson et al., 2025
GREEN
Gabor Riemann EEGNet combining learnable Gabor wavelets with Riemannian geometry and shrinkage estimation.
Paillard et al., 2025
PhaseSPDNet
Phase-Space Embedding combined with SPDNet for geometric analysis of EEG dynamics in reconstructed phase space.
Carrara et al., 2024

Full Bibliography#

Below are the complete bibliographic references for the models and foundational works implemented in SPD Learn.

[1]

Zhiwu Huang and Luc Van Gool. A riemannian network for spd matrix learning. In Proceedings of the AAAI Conference on Artificial Intelligence, volume 31, 2036–2042. 2017. URL: https://ojs.aaai.org/index.php/AAAI/article/view/10866.

[2]

Ce Ju and Cuntai Guan. Tensor-cspnet: a novel geometric deep learning framework for motor imagery classification. IEEE Transactions on Neural Networks and Learning Systems, 34(12):10955–10969, 2023. doi:10.1109/TNNLS.2022.3172108.

[3]

Reinmar J Kobler, Jun-ichiro Hirayama, Qibin Zhao, and Motoaki Kawanabe. Spd domain-specific batch normalization to crack interpretable unsupervised domain adaptation in eeg. In Advances in Neural Information Processing Systems, volume 35, 6219–6235. 2022. URL: https://proceedings.neurips.cc/paper_files/paper/2022/hash/28ef7ee7cd3e03093acc39e1272411b7-Abstract-Conference.html.

[4]

Igor Carrara*, Bruno Aristimunha*, Marie-Constance Corsi, Raphael Y. de Camargo, Sylvain Chevallier, and Théodore Papadopoulo. Geometric neural network based on phase space for bci-eeg decoding. Journal of Neural Engineering, 21(6):016049, 2024. doi:10.1088/1741-2552/ad88a2.

[5]

Antoine Collas, Ce Ju, Nicolas Salvy, and Bertrand Thirion. Riemannian flow matching for brain connectivity matrices via pullback geometry. In The Thirty-ninth Annual Conference on Neural Information Processing Systems. 2025. URL: https://openreview.net/forum?id=NY3LzmUXl7.

[6]

Daniel Brooks, Olivier Schwander, Frédéric Barbaresco, Jean-Yves Schneider, and Matthieu Cord. Riemannian batch normalization for spd neural networks. In Advances in Neural Information Processing Systems, volume 32. 2019. URL: https://proceedings.neurips.cc/paper/2019/hash/6e69ebbfad976d4637bb4b39de261bf7-Abstract.html.

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Zhenhua Lin. Riemannian geometry of symmetric positive definite matrices via cholesky decomposition. SIAM Journal on Matrix Analysis and Applications, 40(4):1353–1370, 2019. doi:10.1137/18M1221084.

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Ce Ju, Reinmar Kobler, Antoine Collas, Motoaki Kawanabe, Cuntai Guan, and Bertrand Thirion. Spd matrix learning for neuroimaging analysis: perspectives, methods, and challenges. arXiv preprint arXiv2504.18882, 2026. URL: https://arxiv.org/abs/2504.18882.

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BibTeX Entries#

For convenience, here are BibTeX entries for citing the main works:

 @inproceedings{huang2017riemannian,
   title={A Riemannian network for SPD matrix learning},
   author={Huang, Zhiwu and Van Gool, Luc},
   booktitle={Proceedings of the AAAI Conference on Artificial Intelligence},
   volume={31},
   number={1},
   year={2017}
 }

 @inproceedings{brooks2019riemannian,
   title={Riemannian batch normalization for SPD neural networks},
   author={Brooks, Daniel and Schwander, Olivier and Barbaresco, Fr{\'e}d{\'e}ric and
           Schneider, Jean-Yves and Cord, Matthieu},
   booktitle={Advances in Neural Information Processing Systems},
   volume={32},
   year={2019}
 }

 @inproceedings{kobler2022spd,
   title={SPD domain-specific batch normalization to crack interpretable
          unsupervised domain adaptation in EEG},
   author={Kobler, Reinmar J and Hirayama, Jun-ichiro and Zhao, Qibin and Kawanabe, Motoaki},
   booktitle={Advances in Neural Information Processing Systems},
   volume={35},
   pages={6219--6235},
   year={2022}
 }

 @inproceedings{pan2022matt,
   title={MAtt: A manifold attention network for EEG decoding},
   author={Pan, Yue-Ting and Chou, Jing-Lun and Wei, Chun-Shu},
   booktitle={Advances in Neural Information Processing Systems},
   volume={35},
   pages={31116--31129},
   year={2022}
 }

 @article{paillard2024green,
   title={GREEN: a lightweight architecture using learnable wavelets and
          Riemannian geometry for biomarker exploration},
   author={Paillard, Joseph and Hipp, Joerg F. and Engemann, Denis A.},
   journal={Patterns},
   volume={6},
   number={1},
   pages={101153},
   year={2025},
   doi={10.1016/j.patter.2025.101153}
 }

 @article{ju2022tensor,
   title={Tensor-CSPNet: A Novel Geometric Deep Learning Framework for
          Motor Imagery Classification},
   author={Ju, Ce and Guan, Cuntai},
   journal={IEEE Transactions on Neural Networks and Learning Systems},
   volume={34},
   number={12},
   pages={10955--10969},
   year={2023},
   doi={10.1109/TNNLS.2022.3172108}
 }

 @article{carrara2024eegspd,
   title={Geometric neural network based on phase space for BCI-EEG decoding},
   author={Carrara*, Igor and Aristimunha*, Bruno and Corsi, Marie-Constance and
           de Camargo, Raphael Y. and Chevallier, Sylvain and Papadopoulo, Th{\'e}odore},
   journal={Journal of Neural Engineering},
   volume={21},
   number={6},
   pages={016049},
   year={2024},
   doi={10.1088/1741-2552/ad88a2}
 }

@article{ju2026spdmatrixlearningneuroimaging,
      title={SPD Matrix Learning for Neuroimaging Analysis: Perspectives, Methods, and Challenges},
      author={Ce Ju and Reinmar Kobler and Antoine Collas and Motoaki Kawanabe and Cuntai Guan and Bertrand Thirion},
      year={2026},
      journal={arXiv preprint arXiv2504.18882},
      url={https://arxiv.org/abs/2504.18882},
}

Citing SPD Learn#

If you use SPD Learn in your research, please cite:

@article{aristimunha2025spdlearn,
  title={SPDlearn: A Geometric Deep Learning Python Library for
         Neural Decoding Through Trivialization},
  author={Aristimunha, Bruno and Ju, Ce and Collas, Antoine and
          Bouchard, Florent and Thirion, Bertrand and
          Chevallier, Sylvain and Kobler, Reinmar},
  journal={To be submitted},
  year={2026},
  url={https://github.com/spdlearn/spd_learn}
}

See also