Are Individuals Always Aware of Their Trauma-Related Intrusive Thoughts? A Study of Meta-Awareness

Individuals are not always aware of their mental content. We tested whether lack of awareness occurs in those who have experienced trauma, with and without posttraumatic stress disorder (PTSD). We also examined the role of proposed cognitive mechanisms (working memory and inhibition) in explaining unnoticed intrusions. Individuals with PTSD (n = 44), and varying levels of symptoms (high posttraumatic stress [PTS]: n = 24; low PTS: n = 37) reported on intrusive thoughts throughout a reading task. Intermittently, participants responded to probes about whether their thoughts were trauma related. Participants were “caught” engaging in unreported trauma-related thoughts (unnoticed intrusions) for between 24 and 27% of the probes in the PTSD and high PTS groups, compared with 15% of occasions in the low PTS group. For trauma-related intrusions only, participants lacked meta-awareness for almost 40% of probes in the PTSD group, which was significantly less than that observed in the other groups (～60%). Contrary to predictions, working memory and response inhibition did not predict unnoticed intrusions. The results suggest that individuals who have experienced significant trauma can lack awareness about the frequency of their trauma-related thoughts. Further research is warranted to identify the mechanisms underpinning the occurrence of unnoticed intrusions.