Valentin DEBENAY defends his doctoral thesis on Thursday, December 18th, 2025, 1:30pm, University of Évry, Pelvoux Site, Yasmina Bestaoui Bx30 Amphitheather.
The thesis defense may be visible via Zoom: https://univ-evry-fr.zoom.us/j/92935151679?pwd=8xS4UHuVMKbTVqYCHPlvj33cC8wkaT.1 .
Title : Investigating new opportunities offered by the “renormalization” method: application to the inversion of electroencephalographic measurements.
Abstract
In this PhD thesis, I extend, evaluate, and ultimately apply to the neuroelectric inverse problem an inversion method known as ‘renormalization’, based on the concept of sensor-network ‘visibility’ and initially developed within the LMEE for characterizing pollutant emission sources in the atmosphere. After a brief overview of key notions regarding the human brain and electroencephalography (EEG), I discuss the positioning of this thesis in relation to the existing literature on EEG signal inversion methods. I then present the atmospheric origins and theoretical foundations of the renormalization method and the ‘visibility’ concept, before explaining how they are extended to address the neuroelectric inverse problem. I subsequently evaluate the method using noisy synthetic EEG signals, and then compare the accuracy of its estimations with those produced by four of the most frequently cited inversion methods in the literature: Minimum Norm, WNMN (dSPM), sLORETA, and eLORETA. Finally, I apply the renormalization method to the detection of physiological markers of vulnerability to age-related cognitive decline in individuals aged 50 to 60 and conduct a statistical analysis of the results. I conclude my presentation by highlighting the main insights gained from this doctoral work and by discussing the perspectives it offers for future studies.
Doctoral thesis jury composition
| Membre du jury | Titre | Lieu d’exercice | Fonction dans le jury |
|---|---|---|---|
| Bertrand RIVET | Full Professor | Grenoble Alpes University | Rapporteur |
| Sébastien SCANNELLA | Director of Research | University of Toulouse | Rapporteur |
| Sylvie GRANON | Full Professor | Paris-Saclay University | Examiner |
| Régine LE BOUQUIN-JEANNÈS | Full Professor | University of Rennes | Examiner |
| Thierry GALLOPIN | Senior Lecturer HDR | Paris Sciences & Lettres University | Examiner |
| Grégory TURBELIN | Full Professor | University of Évry Paris-Saclay | Thesis supervisor |
| Amine CHELLALI | Senior Lecturer | University of Évry Paris-Saclay | Thesis co-supervisor |
| Marie-Hélène FERRER | Doctor and Army Physician | Armed Forces Biomedical Research Institute (IRBA) | Thesis co-supervisor |
- Date: Thursday, December 18, 2025, 1:30 p.m.
- Location: University of Évry, Pelvoux Campus, Yasmina Bestaoui Lecture Hall Bx30, 36 rue du Pelvoux, 91080 ÉVRY-COURCOURONNES
- Zoom link: https://univ-evry-fr.zoom.us/j/92935151679?pwd=8xS4UHuVMKbTVqYCHPlvj33cC8wkaT.1
- Doctoral student: Valentin DEBENAY (University of Évry Paris-Saclay, LMEE/IBISC IRA2 team)
- Thesis supervision: Grégory TURBELIN (Professor, University of Évry, LMEE), thesis supervisor; Amine CHELLALI (Assistant Professor, University of Évry, IBISC IRA2 team), thesis co-supervisor; Marie-Hélène FERRER (Doctor and Army Physician, IRBA)
- The thesis document is available on HAL
