2.1. Ethics
RECRUITMENT
The study protocols and materials were approved by the Purdue University Biomedical Institutional Review Board (IRB protocol #1804020520 (young adults) and IRB-2019-354 (older adults)), and all participants provided written, informed consent, and received monetary compensation for their participation. Before participant recruitment, these studies were registered at clinicaltrials.gov as NCT03649568 (young adults) and NCT04243395 (older adults). The reporting of this research followed the CONSORT reporting guidelines [