Study of the variation of the GABA neurotransmitter during visual stimulation using functional magnetic resonance spectroscopy

• Grant number: 13/06381-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2014
• End date: February 28, 2015
• Field of knowledge: Interdisciplinary Subjects
• Principal Investigator: Gabriela Castellano
• Grantee: Patricia de Oliveira
• Host Institution: Instituto de Física Gleb Wataghin (IFGW). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 13/07559-3 - BRAINN - The Brazilian Institute of Neuroscience and Neurotechnology, AP.CEPID

Abstract

Metabolic changes that occur in the brain underlying neuronal activation are still far from being well understood and quantified, and therefore constitute a subject of study that evokes great interest from the research community. One way to study these variations is through the technique of functional magnetic resonance spectroscopy (fMRS, functional Magnetic Resonance Spectroscopy), in which spectra of a given brain region are measured dynamically, while the individual is subjected to some sensory stimulus or cognitive task. The main goal of this project is to evaluate the variation of the compound gamma-aminobutyric acid (GABA) during visual stimulation, using the fMRS technique. GABA is the chief inhibitory neurotransmitter of the central nervous system, and it has been extensively studied in recent "static" MRS experiments, but little studied in dynamic experiments. The variation of GABA will be evaluated, in principle, through quantification of fMRS spectra that were acquired in a previous project, but, if necessary, new spectra will be acquired. The spectra were measured using the MEGA-PRESS pulse sequence of spectral editing. These data will be quantified using two different methods: LCModel, which is the most widely used method for quantification of in vivo MRS spectra, and Gannet, a set of Matlab routines developed by the group of the researcher Richard Edden, who is one of the world leaders in using MRS for the study of GABA, and who is also a collaborator in this project. This project will be developed in the Neurophysics Group of the Institute of Physics Gleb Wataghin of UNICAMP, whose goal is the development of multimodal techniques for studying the brain, and who has been a pioneer in Brazil in using the fMRS technique.