Glutamate and laser evoked potentials : the role of the cingulate cortex
department or school: Medicine, Faculty of
department or school: Anesthesiology, Pharmacology and Therapeutics, Department of
data provider: DSpace
degree campus: UBCV
creator: Choles, Cassandra
issued: 2023-09-26T18:59:05Z
issued: 2023
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Laser evoked potentials (LEPs) provide an avenue to discern individual differences in nociception, to further understand pain perception. We aimed to investigate resting neurobiological differences that may contribute to the small and large responses to noxious laser stimulation in 50 participants (26 females). To do this, participants underwent a two-part protocol. First, LEPs and verbal pain ratings were collected at four different laser intensities, and the resultant signal amplitudes (N1, N2, and P2) were clustered, forming two respective groups for each LEP outcome of small vs. large signal amplitudes, as well as high vs. low pain ratings. Next, participants underwent a magnetic resonance spectroscopy (MRS) scan to measure excitatory glutamatergic activity within the cingulate cortex at rest in four regions: the anterior (ACC), anterior-mid (aMCC), posterior-mid (pMCC), and posterior (PCC) cingulate cortices. Glutamatergic activity (glutamate, glutamine, and combined (Glx)) was compared between each respective cluster across the four cingulate regions, with sex included as a covariate for glutamine specifically. We found three key findings: 1) Resting glutamatergic activity was significantly higher in anterior vs. posterior regions. 2) Participants with higher verbal pain ratings had significantly higher glutamate concentrations in the ACC. 3) Participants with larger P2 amplitudes had significantly higher glutamate concentrations in the PCC. These findings contribute to our knowledge and understanding of glutamatergic activity in the cingulate cortex at rest. Specifically, that pain ratings and P2 amplitudes (reflecting attention) are not equivocal, although they are both influenced by differences in regional cingulate activity, suggesting the involvement of the ‘hubs’ of the salience and default mode networks through the ACC and PCC, respectively. Further research expanding on our sample size, brain regions, metabolites investigated, and LEPs conditions will …
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/86015
note: GLUTAMATE AND LASER EVOKED POTENTIALS: THE ROLE OF THE CINGULATE CORTEX by Cassandra Choles B.Sc., Lauren�an University, 2021 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Pharmacology) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) September 2023 © Cassandra Choles, 2023 ii The following individuals cer�fy that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the thesis en�tled: Glutamate and laser evoked poten�als: The role of the cingulate cortex submited by Cassandra Choles in par�al fulfilment of the requirements for the degree of Master of Science in Pharmacology Examining Commitee: Dr. John L. K. Kramer, Associate Professor, Anesthesiology, Pharmacology and Therapeu�cs, UBC Supervisor Dr. Alasdair M. Barr, Associate Professor, Anesthesiology, Pharmacology and Therapeu�cs, UBC Supervisory Commitee Member Dr. Brian E. Cairns, Professor, Pharmaceu�cal Sciences, UBC Supervisory Commitee Member iii ABSTRACT Laser evoked poten�als (LEPs) provide an avenue to discern individual differences in nocicep�on, to further understand pain percep�on. We aimed to inves�gate res�ng neurobiological differences that may contribute to the small and large responses to noxious laser s�mula�on in 50 par�cipants (26 females). To do this, par�cipants underwent a two-part protocol. First, LEPs and verbal pain ra�ngs were collected at four different laser intensi�es, and the resultant signal amplitudes (N1, N2, and P2) were clustered, forming two respec�ve groups for each LEP outcome of small vs. large signal amplitudes, as well as high vs. low pain ra�ngs. Next, par�cipants underwent a magne�c resonance spectroscopy (MRS) scan to measure excitatory glutamatergic ac�vity within the cingulate cortex at rest in four regions: the anterior (ACC), anterior-mid (aMCC), posterior-mid (pMCC), and posterior (PCC) cingulate cor�ces. Glutamatergi…
has type: Thesis/Dissertation
date issued: 2023-11
is shown at: 10.14288/1.0436885
language: eng
degree discipline: Pharmacology and Therapeutics
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Kramer, John L. K.
type: Text
identifier URI: http://hdl.handle.net/2429/86015