AUTHOR=Apkarian Apkar Vania TITLE=The Necessity of Methodological Advances in Pain Research: Challenges and Opportunities JOURNAL=Frontiers in Pain Research VOLUME=2 YEAR=2021 URL=https://www.frontiersin.org/journals/pain-research/articles/10.3389/fpain.2021.634041 DOI=10.3389/fpain.2021.634041 ISSN=2673-561X