Cross-Frequency Graph-Transformer Networks for Subject-Independent EEG Classification of Neurodegenerative Disorders
Research Article  ·  Published: 13 July 2026
Issue cover
Journal of Artificial Intelligence in Bioinformatics
Volume 2, Issue 2, 2026: 22-30
Research Article Open Access

Cross-Frequency Graph-Transformer Networks for Subject-Independent EEG Classification of Neurodegenerative Disorders

1 Department of Bioinformatics and Biotechnology, Government College University Faisalabad (GCUF), Faisalabad 38000, Pakistan
2 Centre for Cognitive and Brain Sciences, University of Macau, Macau SAR, China
3 Faculty of Science and Technology, University of Macau, Macau SAR, China
4 Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
5 Division of Industrial and Logistics Engineering Technology, Faculty of Engineering and Technology, King Mongkut's University of Technology North Bangkok, Rayong Campus, Rayong 21120, Thailand
* Corresponding Author: Chayut Bunterngchit, [email protected]
Volume 2, Issue 2

Article Information

Abstract

Resting-state EEG offers a low-cost, non-invasive biomarker for Alzheimer's and Parkinson's diseases, yet most deep learning models fail to generalize to new patients due to subject-dependent evaluation protocols, isolated frequency-band processing, and the neglect of cross-frequency interactions. We propose CFGT-Net, a Cross-Frequency Graph-Transformer Network. For each EEG epoch, five canonical bands are processed by a graph attention encoder on a learnable phase-lag index adjacency to produce spatial embeddings. A cross-frequency coupling (CFC) attention models band interactions, a temporal transformer tracks their evolution across epochs, and a correlation-alignment loss enforces subject-invariant representations. Evaluated under leave-one-subject-out on two public datasets, CFGT-Net achieves 88.6% accuracy (0.931 AUC) for AD and 85.3% accuracy (0.902 AUC) for PD, outperforming prior methods including DICE-Net. Ablations confirm the adaptive graph, CFC module, and temporal transformer each contribute gains, while learned connectivity highlights fronto-parietal links consistent with known disease patterns. Limitations include small cohorts and residual per-subject variance under LOSO. Modeling adaptive connectivity with cross-frequency coupling improves subject-independent EEG screening and yields interpretable connectivity maps for clinical inspection.

Graphical Abstract

Cross-Frequency Graph-Transformer Networks for Subject-Independent EEG Classification of Neurodegenerative Disorders

Keywords

electroencephalography neurodegenerative disorders graph neural networks cross-frequency coupling transformers subject-independent classification

Data Availability Statement

Data will be made available on request.

Funding

This work was supported without any funding.

Conflicts of Interest

The authors declare no conflicts of interest.

AI Use Statement

The authors declare that ChatGPT-5.5 (April 2025 version, OpenAI, San Francisco, CA, USA) was used for language editing and rewriting of parts of the manuscript to improve clarity and effectiveness. The authors have carefully reviewed, revised, and verified all AI-assisted output and take full responsibility for the content of the manuscript.

Ethical Approval and Consent to Participate

This study used publicly available de-identified EEG data from OpenNeuro (ds004504 and ds002778). The original data collection received ethical approval from the respective institutional review boards, and all participants provided informed consent. As a secondary analysis of anonymized data, this study was exempt from additional ethics review.

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Cite This Article

APA Style
Rehman, H. M. A., Li, X., & Bunterngchit, C. (2026). Cross-Frequency Graph-Transformer Networks for Subject-Independent EEG Classification of Neurodegenerative Disorders. Journal of Artificial Intelligence in Bioinformatics, 2(2), 22-30. https://doi.org/10.62762/JAIB.2026.815471
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TY  - JOUR
AU  - Rehman, H. M. Abdul
AU  - Li, Xiaoli
AU  - Bunterngchit, Chayut
PY  - 2026
DA  - 2026/07/13
TI  - Cross-Frequency Graph-Transformer Networks for Subject-Independent EEG Classification of Neurodegenerative Disorders
JO  - Journal of Artificial Intelligence in Bioinformatics
T2  - Journal of Artificial Intelligence in Bioinformatics
JF  - Journal of Artificial Intelligence in Bioinformatics
VL  - 2
IS  - 2
SP  - 22
EP  - 30
DO  - 10.62762/JAIB.2026.815471
UR  - https://www.icck.org/article/abs/JAIB.2026.815471
KW  - electroencephalography
KW  - neurodegenerative disorders
KW  - graph neural networks
KW  - cross-frequency coupling
KW  - transformers
KW  - subject-independent classification
AB  - Resting-state EEG offers a low-cost, non-invasive biomarker for Alzheimer's and Parkinson's diseases, yet most deep learning models fail to generalize to new patients due to subject-dependent evaluation protocols, isolated frequency-band processing, and the neglect of cross-frequency interactions. We propose CFGT-Net, a Cross-Frequency Graph-Transformer Network. For each EEG epoch, five canonical bands are processed by a graph attention encoder on a learnable phase-lag index adjacency to produce spatial embeddings. A cross-frequency coupling (CFC) attention models band interactions, a temporal transformer tracks their evolution across epochs, and a correlation-alignment loss enforces subject-invariant representations. Evaluated under leave-one-subject-out on two public datasets, CFGT-Net achieves 88.6% accuracy (0.931 AUC) for AD and 85.3% accuracy (0.902 AUC) for PD, outperforming prior methods including DICE-Net. Ablations confirm the adaptive graph, CFC module, and temporal transformer each contribute gains, while learned connectivity highlights fronto-parietal links consistent with known disease patterns. Limitations include small cohorts and residual per-subject variance under LOSO. Modeling adaptive connectivity with cross-frequency coupling improves subject-independent EEG screening and yields interpretable connectivity maps for clinical inspection.
SN  - 3068-7535
PB  - Institute of Central Computation and Knowledge
LA  - English
ER  - 
BibTeX Format
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@article{Rehman2026CrossFrequ,
  author = {H. M. Abdul Rehman and Xiaoli Li and Chayut Bunterngchit},
  title = {Cross-Frequency Graph-Transformer Networks for Subject-Independent EEG Classification of Neurodegenerative Disorders},
  journal = {Journal of Artificial Intelligence in Bioinformatics},
  year = {2026},
  volume = {2},
  number = {2},
  pages = {22-30},
  doi = {10.62762/JAIB.2026.815471},
  url = {https://www.icck.org/article/abs/JAIB.2026.815471},
  abstract = {Resting-state EEG offers a low-cost, non-invasive biomarker for Alzheimer's and Parkinson's diseases, yet most deep learning models fail to generalize to new patients due to subject-dependent evaluation protocols, isolated frequency-band processing, and the neglect of cross-frequency interactions. We propose CFGT-Net, a Cross-Frequency Graph-Transformer Network. For each EEG epoch, five canonical bands are processed by a graph attention encoder on a learnable phase-lag index adjacency to produce spatial embeddings. A cross-frequency coupling (CFC) attention models band interactions, a temporal transformer tracks their evolution across epochs, and a correlation-alignment loss enforces subject-invariant representations. Evaluated under leave-one-subject-out on two public datasets, CFGT-Net achieves 88.6\% accuracy (0.931 AUC) for AD and 85.3\% accuracy (0.902 AUC) for PD, outperforming prior methods including DICE-Net. Ablations confirm the adaptive graph, CFC module, and temporal transformer each contribute gains, while learned connectivity highlights fronto-parietal links consistent with known disease patterns. Limitations include small cohorts and residual per-subject variance under LOSO. Modeling adaptive connectivity with cross-frequency coupling improves subject-independent EEG screening and yields interpretable connectivity maps for clinical inspection.},
  keywords = {electroencephalography, neurodegenerative disorders, graph neural networks, cross-frequency coupling, transformers, subject-independent classification},
  issn = {3068-7535},
  publisher = {Institute of Central Computation and Knowledge}
}

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CC BY Copyright © 2026 by the Author(s). Published by Institute of Central Computation and Knowledge. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
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