AUTHOR=Teixeira Micael , Mancini Christian , Wicht Corentin Aurèle , Maestretti Gianluca , Kuntzer Thierry , Cazzoli Dario , Mouthon Michael , Annoni Jean-Marie , Chabwine Joelle Nsimire 

TITLE=Beta Electroencephalographic Oscillation Is a Potential GABAergic Biomarker of Chronic Peripheral Neuropathic Pain

JOURNAL=Frontiers in Neuroscience

VOLUME=Volume 15 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2021.594536

DOI=10.3389/fnins.2021.594536

ISSN=1662-453X

ABSTRACT=The aim of this preliminary investigation was to assess beta (β) oscillation, a marker of the brain GABAergic signalling, as a potential objective pain marker, hence contributing at the same time to the mechanistic approach of pain management. 
This case-control observational study measured β EEG oscillation in 12 right-handed adult male with chronic neuropathic pain and 10 matched controls (~55 years). Participants were submitted to clinical evaluation (pain visual analog scale, Hospital Anxiety and Depression scale) and a 24-minute high density EEG recording (BIOSEMI). Data were analyzed using the EEGlab toolbox (MATLAB), SPSS and R.
The global power spectrum computed within the low (Lβ, 13-20 Hz) and the high (Hβ, 20-30 Hz) β frequency sub-bands was significantly lower in patients than in controls, and accordingly, Lβ was negatively correlated to the pain visual analog scale (R = -.931, p = .007), while Hβ correlation was at the edge of significance (R = -.805; p = .053). Patients’anxiety was correlated to pain intensity (R = .755; p = .003). Normalization of the low and high β GPS to the GPS of the full frequency range, while confirming the significant Lβ power decrease in chronic neuropathic pain patients, vanished the significance of the Hβ decrease, as well as the correlation between Lβ power and pain intensity.
Our results suggest that the GABAergic Lβ EEG oscillation is affected by chronic neuropathic pain. Confirming the Lβ GPS decrease as well as the correlation with pain intensity in larger studies would open new opportunities for clinical application of GABA-modifying therapies.