Page 315 - MEGIN Book Of Abstracts - 2023

correlated with lower neuropsychological test perfor- ed using MEG source localization. Relative to matched
mance. This study provides an integrated framework controls, participants with an mTBI had a smaller P1 in
for condensing large source-imaging variable sets into the left hemisphere and a smaller N1 in the right hemi-
optimal combinations of regions and frequencies with sphere. Also, mTBI participants showed inversed activa-
high diagnostic accuracy and cognitive relevance in tion patterns across the hemispheres during the N1
cmTBI. The all-frequency model offered more discrimi- in MEG compared with controls. This is the first study
native power than each frequency-band model alone. to investigate the impact of mTBI on neuronal source
This approach offers an effective path for optimal activations during early visual processing in an aging
characterization of behaviorally relevant neuroimaging population. Results showed that when aging individu-
features in neurological and psychiatric disorders. als suffer from an mTBI, there are perturbations in the
amplitude and hemispheric dominance patterns in the
Keywords: Veterans, delta rhythm, gamma rhythm, ma- visual P1 and N1 responses that are visible for months
chine learning, military service members, neuropsychol- to years following the injury. Our findings indicate
ogy, resting-state MEG, traumatic brain injury that mTBI can lead to modifications of sensory and/
or perceptual responses, suggesting possible adaptive
Human brain mapping (2021), Vol. 42, No. 7 (33449442) (2 functional reorganization following mTBI.
citations)
Keywords: EEG, MEG, N1, P1, aging, concussion, mild trau-
matic brain injury (mTBI), visual ERP
Interhemispheric differences in P1 and N1
amplitude in EEG and MEG differ across older Psychophysiology (2021), Vol. 58, No. 3 (33347633) (2
individuals with a concussion compared with age- citations)
matched controls (2021)

Desjardins, Martine; Drisdelle, Brandi Lee; Lefebvre, Portable neuromodulation induces neuroplasticity
Christine; Gagnon, Jean-Francois; De Beaumont, Louis; to re-activate motor function recovery from brain
Jolicoeur, Pierre injury: a high-density MEG case study (2020)

Montreal Sacred-Heart Hospital Research Centre, Montréal, D'Arcy, Ryan C N; Greene, Trevor; Greene, Debbie;
QC, Canada; Birkbeck College, University of London, Lon- Frehlick, Zack; Fickling, Shaun D; Campbell, Natasha;
don, UK; Department of Psychology, Université de Montréal, Etheridge, Tori; Smith, Christopher; Bollinger, Fabio;
Montréal, QC, Canada; Department of Surgery, Université Danilov, Yuri; Livingstone, Ashley; Tannouri, Pamela;
de Montréal, Montréal, QC, Canada; Centre de recherche de Martin, Pauline; Lakhani, Bimal
l'Institut universitaire de gériatrie de Montréal, Montréal, QC,
Canada Centre for Brain Health (Radiology), University of British
Columbia, Vancouver, Canada. ryan@healthtechconnex.
ABSTRACT We studied the effects of mild traumatic com; BrainNET, Health and Technology District, Vancou-
brain injury (mTBI) in an aging population. We exam- ver, Canada; Applied Sciences and Sciences, Simon Fraser
ined visual search with event-related potentials (ERPs) University, Vancouver, Canada; Pavlov Institute of Physiology,
and event-related fields (ERF) for a lateral color single- Russian Academy of Science, Sankt Petersburg, Russia; Neuro-
ton focusing on the P1 and N1 in each hemisphere. Motion Rehabilitation, Vancouver, Canada; BrainNET, Health
Forty participants (19 mTBI and 21 controls) aged 50 to and Technology District, Vancouver, Canada. bimal.lakhani@
72 performed a visual search task, while we recorded healthtechconnex.com
their magnetoencephalogram (MEG) with simultane-
ous electroencephalogram (EEG). We compared visual BACKGROUND In a recent high-profile case study, we
ERPs and ERFs and associated cortical activity estimat- used functional magnetic resonance imaging (fMRI)

 ontents  Index 294
C