AUTHOR=Ceccarini Jenny , Liu Heather , Van Laere Koen , Morris Evan D. , Sander Christin Y. TITLE=Methods for Quantifying Neurotransmitter Dynamics in the Living Brain With PET Imaging JOURNAL=Frontiers in Physiology VOLUME=Volume 11 - 2020 YEAR=2020 URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2020.00792 DOI=10.3389/fphys.2020.00792 ISSN=1664-042X ABSTRACT=PET neuroimaging in neuropsychiatry is a powerful tool for the quantification of molecular brain targets to characterize disease, assess disease subtype differences, evaluate short and long-term effects of treatments, or even to measure neurotransmitter levels in healthy and psychiatric conditions. In this work, we present different methodological approaches (time-invariant models and models with time-varying terms) that have been used to measure dynamic changes in neurotransmitter levels induced by pharmacological or behavioural challenges in humans. The developments and potential use of hybrid PET/MRI for neurotransmission brain research will also be highlighted.