To the Editor: For a psychiatrist unfamiliar with the specific criteria for posttraumatic stress disorder (PTSD) and acute stress disorder, there were two recent articles by Ruth A. Lanius, M.D., Ph.D., et al. (1) and by Chris R. Brewin, Ph.D., et al. (2) that were extremely enlightening. The first group reported that a husband and wife who experienced the same trauma had different emotional and physiological responses to it. They were seen and assessed 4 weeks after the trauma. Both met criteria for acute stress disorder and PTSD. The wife had a high score on the Peritraumatic Dissociative Experiences Scale, but both had low scores on the Dissociative Experiences Scale. They also had different responses to script-driven traumatic imagery, as measured by T4 functional magnetic resonance imaging, heart rate, and self-reported measures.