Studying the Modification of Attention Bias Remotely After Trauma

The investigators will complete an entirely remote randomized controlled trial (RCT) comparing 14 sessions of attention bias modification (ABM), attention control training (ACT), placebo neutral attention training, and a final control condition with daily questions in 1,897 individuals with clinically significant Post-traumatic Stress Symptoms (PTSS) (defined as PCL-5 score ≥ 33). To assess effects of the training and control conditions, the investigators will administer tests of threat-related attention bias and variability, and self-report assessments of PTSS, depression, anxiety, and perceived stress at baseline, after one and two weeks of training, and at eight-week follow up. The investigators plan to screen and confirm interest from over 3,000 eligible participants over a period of 24 months to enroll and randomize 1,897 participants with the end goal of 1,232 completers (176 per condition).

Inclusion Criteria: * Aged 18 to 65 years * Score at or above 33 on the PCL-5, * Able and willing to perform daily smartphone training for two weeks * Fluent English comprehension. * Owns Android or iPhone smartphone Exclusion Criteria: * Does not have Android or iPhone Operating System (iOS) smartphone running sufficient software (i.e. at least iOS 10.1), and is not willing to update * Active suicidality.