The trajectory of cortical GABA across the lifespan, an individual participant data meta-analysis of edited MRS studies
Abstract
GABA is the principal inhibitory neurotransmitter in the human brain and can be measured with Magnetic Resonance Spectroscopy (MRS). Conflicting accounts report decreases and increases in cortical GABA levels across the lifespan. This incompatibility may be an artifact of the size and age-range of the samples utilized in these studies. No single study to date has included the entire lifespan. In this study, 8 suitable datasets were integrated to generate a model of the trajectory of frontal GABA estimates (as reported through edited MRS; both expressed as ratios and in institutional units). across the lifespan. Data were fit using both a log-normal curve and a nonparametric spline as regression models using a multi-level Bayesian model utilizing the Stan language. Integrated data show the lifespan trajectory of frontal GABA measures involves an early period of increase, followed by a period of stability during early adulthood, with a gradual decrease during adulthood and aging that is described well by both spline and log-normal models. The information gained will provide a general framework to inform expectations of future studies based on the age of the population being studied.
Data availability
All data and code used in this manuscript can be found here https://osf.io/rmhwc/
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The trajectory of cortical GABA levels across the lifespanOpen Science Framework, rmhwc.
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Big GABA: Edited MR spectroscopy at 24 research sites.doi: 10.1016/j.neuroimage.2017.07.021.
Article and author information
Author details
Funding
National Institutes of Health (KO1AA025306)
- Eric C Porges
Evelyn F. McKnight Brain Research Foundation
- Eric C Porges
Center for Cognitive Aging and Memory at the University of Florida
- Eric C Porges
National Institutes of Health (R00MH107719)
- Nicolaas AJ Puts
National Institutes of Health (R01EB016089)
- Richard AE Edden PhD
National Institutes of Health (R01MH106564)
- Richard AE Edden PhD
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Chris I Baker, National Institute of Mental Health, National Institutes of Health, United States
Version history
- Received: August 28, 2020
- Accepted: May 30, 2021
- Accepted Manuscript published: June 1, 2021 (version 1)
- Version of Record published: June 24, 2021 (version 2)
Copyright
© 2021, Porges et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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