Introducing Region Based Pooling for handling a varied number of EEG channels for deep learning models

IntroductionA challenge when applying an artificial intelligence (AI) deep learning (DL) approach to novel electroencephalography (EEG) data, is the DL architecture's lack of adaptability to changing numbers of EEG channels. That is, the number of channels cannot vary neither in the training da...

Full description

Bibliographic Details
Main Authors: Thomas Tveitstøl, Mats Tveter, Ana S. Pérez T., Christoffer Hatlestad-Hall, Anis Yazidi, Hugo L. Hammer, Ira R. J. Hebold Haraldsen
Format: Article
Language:English
Published: Frontiers Media S.A. 2024-01-01
Series:Frontiers in Neuroinformatics
Subjects:
Online Access:https://www.frontiersin.org/articles/10.3389/fninf.2023.1272791/full
_version_ 1797339155680722944
author Thomas Tveitstøl
Thomas Tveitstøl
Mats Tveter
Mats Tveter
Ana S. Pérez T.
Ana S. Pérez T.
Christoffer Hatlestad-Hall
Anis Yazidi
Hugo L. Hammer
Hugo L. Hammer
Ira R. J. Hebold Haraldsen
author_facet Thomas Tveitstøl
Thomas Tveitstøl
Mats Tveter
Mats Tveter
Ana S. Pérez T.
Ana S. Pérez T.
Christoffer Hatlestad-Hall
Anis Yazidi
Hugo L. Hammer
Hugo L. Hammer
Ira R. J. Hebold Haraldsen
author_sort Thomas Tveitstøl
collection DOAJ
description IntroductionA challenge when applying an artificial intelligence (AI) deep learning (DL) approach to novel electroencephalography (EEG) data, is the DL architecture's lack of adaptability to changing numbers of EEG channels. That is, the number of channels cannot vary neither in the training data, nor upon deployment. Such highly specific hardware constraints put major limitations on the clinical usability and scalability of the DL models.MethodsIn this work, we propose a technique for handling such varied numbers of EEG channels by splitting the EEG montages into distinct regions and merge the channels within the same region to a region representation. The solution is termed Region Based Pooling (RBP). The procedure of splitting the montage into regions is performed repeatedly with different region configurations, to minimize potential loss of information. As RBP maps a varied number of EEG channels to a fixed number of region representations, both current and future DL architectures may apply RBP with ease. To demonstrate and evaluate the adequacy of RBP to handle a varied number of EEG channels, sex classification based solely on EEG was used as a test example. The DL models were trained on 129 channels, and tested on 32, 65, and 129-channels versions of the data using the same channel positions scheme. The baselines for comparison were zero-filling the missing channels and applying spherical spline interpolation. The performances were estimated using 5-fold cross validation.ResultsFor the 32-channel system version, the mean AUC values across the folds were: RBP (93.34%), spherical spline interpolation (93.36%), and zero-filling (76.82%). Similarly, on the 65-channel system version, the performances were: RBP (93.66%), spherical spline interpolation (93.50%), and zero-filling (85.58%). Finally, the 129-channel system version produced the following results: RBP (94.68%), spherical spline interpolation (93.86%), and zero-filling (91.92%).ConclusionIn conclusion, RBP obtained similar results to spherical spline interpolation, and superior results to zero-filling. We encourage further research and development of DL models in the cross-dataset setting, including the use of methods such as RBP and spherical spline interpolation to handle a varied number of EEG channels.
first_indexed 2024-03-08T09:41:52Z
format Article
id doaj.art-8216ec604ec042b3b665f49ae8bb0927
institution Directory Open Access Journal
issn 1662-5196
language English
last_indexed 2024-03-08T09:41:52Z
publishDate 2024-01-01
publisher Frontiers Media S.A.
record_format Article
series Frontiers in Neuroinformatics
spelling doaj.art-8216ec604ec042b3b665f49ae8bb09272024-01-30T04:16:09ZengFrontiers Media S.A.Frontiers in Neuroinformatics1662-51962024-01-011710.3389/fninf.2023.12727911272791Introducing Region Based Pooling for handling a varied number of EEG channels for deep learning modelsThomas Tveitstøl0Thomas Tveitstøl1Mats Tveter2Mats Tveter3Ana S. Pérez T.4Ana S. Pérez T.5Christoffer Hatlestad-Hall6Anis Yazidi7Hugo L. Hammer8Hugo L. Hammer9Ira R. J. Hebold Haraldsen10Department of Neurology, Oslo University Hospital, Oslo, NorwayInstitute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, NorwayDepartment of Neurology, Oslo University Hospital, Oslo, NorwayInstitute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, NorwayDepartment of Neurology, Oslo University Hospital, Oslo, NorwayInstitute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, NorwayDepartment of Neurology, Oslo University Hospital, Oslo, NorwayDepartment of Computer Science, Oslo Metropolitan University, Oslo, NorwayDepartment of Computer Science, Oslo Metropolitan University, Oslo, NorwayDepartment of Holistic Systems, SimulaMet, Oslo, NorwayDepartment of Neurology, Oslo University Hospital, Oslo, NorwayIntroductionA challenge when applying an artificial intelligence (AI) deep learning (DL) approach to novel electroencephalography (EEG) data, is the DL architecture's lack of adaptability to changing numbers of EEG channels. That is, the number of channels cannot vary neither in the training data, nor upon deployment. Such highly specific hardware constraints put major limitations on the clinical usability and scalability of the DL models.MethodsIn this work, we propose a technique for handling such varied numbers of EEG channels by splitting the EEG montages into distinct regions and merge the channels within the same region to a region representation. The solution is termed Region Based Pooling (RBP). The procedure of splitting the montage into regions is performed repeatedly with different region configurations, to minimize potential loss of information. As RBP maps a varied number of EEG channels to a fixed number of region representations, both current and future DL architectures may apply RBP with ease. To demonstrate and evaluate the adequacy of RBP to handle a varied number of EEG channels, sex classification based solely on EEG was used as a test example. The DL models were trained on 129 channels, and tested on 32, 65, and 129-channels versions of the data using the same channel positions scheme. The baselines for comparison were zero-filling the missing channels and applying spherical spline interpolation. The performances were estimated using 5-fold cross validation.ResultsFor the 32-channel system version, the mean AUC values across the folds were: RBP (93.34%), spherical spline interpolation (93.36%), and zero-filling (76.82%). Similarly, on the 65-channel system version, the performances were: RBP (93.66%), spherical spline interpolation (93.50%), and zero-filling (85.58%). Finally, the 129-channel system version produced the following results: RBP (94.68%), spherical spline interpolation (93.86%), and zero-filling (91.92%).ConclusionIn conclusion, RBP obtained similar results to spherical spline interpolation, and superior results to zero-filling. We encourage further research and development of DL models in the cross-dataset setting, including the use of methods such as RBP and spherical spline interpolation to handle a varied number of EEG channels.https://www.frontiersin.org/articles/10.3389/fninf.2023.1272791/fullEEGdeep learningmachine learningcross-datasetcross-channel systemconvolutional neural networks
spellingShingle Thomas Tveitstøl
Thomas Tveitstøl
Mats Tveter
Mats Tveter
Ana S. Pérez T.
Ana S. Pérez T.
Christoffer Hatlestad-Hall
Anis Yazidi
Hugo L. Hammer
Hugo L. Hammer
Ira R. J. Hebold Haraldsen
Introducing Region Based Pooling for handling a varied number of EEG channels for deep learning models
Frontiers in Neuroinformatics
EEG
deep learning
machine learning
cross-dataset
cross-channel system
convolutional neural networks
title Introducing Region Based Pooling for handling a varied number of EEG channels for deep learning models
title_full Introducing Region Based Pooling for handling a varied number of EEG channels for deep learning models
title_fullStr Introducing Region Based Pooling for handling a varied number of EEG channels for deep learning models
title_full_unstemmed Introducing Region Based Pooling for handling a varied number of EEG channels for deep learning models
title_short Introducing Region Based Pooling for handling a varied number of EEG channels for deep learning models
title_sort introducing region based pooling for handling a varied number of eeg channels for deep learning models
topic EEG
deep learning
machine learning
cross-dataset
cross-channel system
convolutional neural networks
url https://www.frontiersin.org/articles/10.3389/fninf.2023.1272791/full
work_keys_str_mv AT thomastveitstøl introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT thomastveitstøl introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT matstveter introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT matstveter introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT anasperezt introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT anasperezt introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT christofferhatlestadhall introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT anisyazidi introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT hugolhammer introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT hugolhammer introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels
AT irarjheboldharaldsen introducingregionbasedpoolingforhandlingavariednumberofeegchannelsfordeeplearningmodels