This report covers Year 2 of the project. This project examines the impact of disturbances in normal sleep and circadian regulation on mechanisms underlying vulnerability to, and maintenance of, posttraumatic stress disorder PTSD. The goal of Year 2 was data collection and initial validation of data collection procedures and harmonization with Monash. We proposed to complete 30 participants 45 in total with year 1. Progress was slowed due to COVID19, which prompted our VA facility to shut down all human research the fall. Our study, which requires a hospital stay, was finally approved for collection in October with mitigation procedures in place. We have completed 18 subjects 30 of target. However we do have 6 weeks now booked for collection and a large list of applicants for the study. During the COVID period we examined data for errors and trained and harmonized sleep scoring across the study. We have seen exceptional interest in the study since recruitment opened and hope to make up for lost time this year.