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Hemodynamic correlates of fluctuations in neuronal excitability: A simultaneous Paired Associative Stimulation (PAS) and functional near infra-red spectroscopy (fNIRS) study

Author(s): Cai Z; Pellegrino G; Spilkin A; Delaire E; Uji M; Abdallah C; Lina JM; Fecteau S; Grova C;

Background: The relationship between task-related hemodynamic activity and brain excitability is poorly understood in humans as it is technically challenging to combine simultaneously non-invasive brain stimulation and neuroimaging modalities. Cortical exci...

Article GUID: 40567300
Is Adipose Tissue Inflammation the Culprit of Obesity-Associated Comorbidities?

Author(s): Turner L; Wanasinghe AI; Brunori P; Santosa S;

In individuals with obesity, the onset of chronic comorbidities coincides with the excessive accumulation of adipose tissue in various tissue beds. As obesity progresses, adipose tissue becomes increasingly dysfunctional causing chronic low-grade inflammati...

Article GUID: 40533358
Visual Features in Stereo-Electroencephalography to Predict Surgical Outcome: A Multicenter Study

Author(s): Abdallah C; Thomas J; Aron O; Avigdor T; Jaber K; Doležalová I; Mansilla D; Nevalainen P; Parikh P; Singh J; Beniczky S; Kahane P; Minotti L...

Objective: Epilepsy surgery needs predictive features that are easily implemented in clinical practice. Previous studies are limited by small sample sizes, lack of external validation, and complex ...

Article GUID: 40519108
Morphological characteristics of the thoracolumbar fascia: relationship to chronic low back pain and back extension strength

Author(s): Caron FP; Martin Smith C; Naghdi N; Iorio OC; Bertrand C; Fortin M;

Purpose: The purpose of this study was to investigate the relationship between different characteristics of the Thoracolumbar Fascia (TLF) (e.g., length, epimuscular fat distribution) with pain status and lumbar extension strength in a sample of participant...

Article GUID: 40498329
What is the role of non-surgical clinicians in the assessment and management of degenerative cervical myelopathy? - Insights from the RECODE-DCM peri-operative rehabilitation incubator

Author(s): Chauhan RV; Demetriades AK; Boerger TF; Lantz JM; Treanor C; Kalsi-Ryan S; Kumar V; Wood L; Plener J; Wilson N; Fortin M; Ammendolia C; Paus...

Introduction: Evidence on degenerative cervical myelopathy (DCM) has frequently focussed on surgical management, overlooking the role of non-surgical clinicians. Their contributions in the patient ...

Article GUID: 40487873
Spectral and network investigation reveals distinct power and connectivity patterns between phasic and tonic REM sleep

Author(s): Avigdor T; Peter-Derex L; Ho A; Schiller K; Wang Y; Abdallah C; Delaire E; Jaber K; Travnicek V; Grova C; Frauscher B;...

Although rapid eye movement (REM) sleep is often thought of as a singular state, it consists of two substates, phasic and tonic REM, defined by the presence (respectively absence) of bursts of rapi...

Article GUID: 40394955
NIRSTORM: a Brainstorm extension dedicated to functional near-infrared spectroscopy data analysis, advanced 3D reconstructions, and optimal probe design

Author(s): Delaire É; Vincent T; Cai Z; Machado A; Hugueville L; Schwartz D; Tadel F; Cassani R; Bherer L; Lina JM; Pélégrini-Issac M; Grova C;...

Significance: Understanding the brain's complex functions requires multimodal approaches that combine data from various neuroimaging techniques. Functional near-infrared spectroscopy (fNIRS) of...

Article GUID: 40375973
Relationship Between Lumbar Multifidus Morphometry and Pain/Disability in Individuals With Chronic Nonspecific Low Back Pain After Considering Demographics, Fear-Avoidance Beliefs, Insomnia, and Spinal Degenerative Changes

Author(s): Pinto SM; Cheung JPY; Samartzis D; Karppinen J; Zheng YP; Pang MYC; Fortin M; Wong AYL;

Background: Although individuals with chronic low back pain (CLBP) show increased fatty infiltration in the lumbar multifidus muscle (LMM), it remains unclear whether LMM changes are related to clinical outcomes (such as pain and disability) after consideri...

Article GUID: 40376565
Multiscale gradients of corticopontine structural connectivity

Author(s): Rousseau PN; Bazin PL; Steele CJ;

The cerebellum's involvement in a range of cognitive, emotional, and motor processes has become increasingly evident. Given the uniformity of the cerebellar cortex's cellular architecture its contributions to varied processes are thought be partiall...

Article GUID: 40355513
Title:Hemodynamic correlates of fluctuations in neuronal excitability: A simultaneous Paired Associative Stimulation (PAS) and functional near infra-red spectroscopy (fNIRS) study
Authors:Cai Z,  Pellegrino G,  Spilkin A,  Delaire E,  Uji M,  Abdallah C,  Lina JM,  Fecteau S,  Grova C, 
Link:https://pubmed.ncbi.nlm.nih.gov/40567300/
DOI:10.1016/j.ynirp.2022.100099
Category:
PMID:40567300
Dept Affiliation: PERFORM
1 Multimodal Functional Imaging Lab, Department of Physics and PERFORM Centre, Concordia University, Montréal, Québec, Canada.
2 Neurology and Neurosurgery Department, Montreal Neurological Institute, McGill University, Montréal, Québec, Canada.
3 Multimodal Functional Imaging Lab, Biomedical Engineering Department, McGill University, Montréal, Québec, Canada.
4 Département de Génie Electrique, École de Technologie Supérieure, Montréal, Québec, Canada.
5 Centre De Recherches En Mathématiques, Montréal, Québec, Canada.
6 CERVO Brain Research Centre, Centre Intégré Universitaire De Santé Et De Services Sociaux De La Capitale-Nationale, Canada.
7 Department of Psychiatry and Neurosciences, Faculty of Medicine, Université Laval, Canada.

Description:

Background: The relationship between task-related hemodynamic activity and brain excitability is poorly understood in humans as it is technically challenging to combine simultaneously non-invasive brain stimulation and neuroimaging modalities. Cortical excitability corresponds to the readiness to become active and as such it may be linked to metabolic demand.

Hypotheses: Cortical excitability and hemodynamic activity are positively linked so that increases in hemodynamic activity correspond to increases in excitability and vice-versa.

Methods: Magnitudes of excitability and hemodynamic activity were investigated via simultaneous Transcranial Magnetic Stimulation (TMS) and functional Near Infrared Spectroscopy (fNIRS). Sixteen healthy subjects participated in a sham-controlled, pseudorandomized, counterbalanced study with PAS (PAS10/PAS25/Sham) on the right primary motor cortex (M1). The relationship between M1 excitability (Motor Evoked Potentials, MEP) and hemodynamic responses to finger tapping reconstructed via personalized fNIRS was assessed.

Results: Hemodynamic activity exhibited a significant correlation with cortical excitability: increased HbO and HbR (absolute amplitude) corresponded to increased excitability and vice-versa (r = 0.25; p = 0.03 and r = 0.16; p = 0.17, respectively). The effect of PAS on excitability and hemodynamic activity showed a trend of positive correlation with MEP ratios (post-PAS/pre-PAS) linked to HbO and HbR ratios (r = 0.19, p = 0.29; r = 0.18, p = 0.30, respectively).

Conclusions: TMS-fNIRS is a suitable technique for simultaneous investigation of excitability and hemodynamic responses and indicates a relationship between these two cortical properties. PAS effect is not limited to cortical excitability but also impacts hemodynamic processes. These findings have an impact on the application of neuromodulatory interventions in patients with neuropsychiatric disorders.