Long-term memory for the terrorist attack of September 11: flashbulb memories, event memories, and the factors that influence their retention.
Level 3 - non-randomized controlled study
Longitudinal multi-wave cohort survey study
PubMed 19397377 · doi:10.1037/a0015527
What was done
More than 3,000 individuals across 7 U.S. cities completed surveys regarding their recollection of learning about the September 11 terrorist attacks (flashbulb memories) and factual details about the event (event memories) at 1 week, 11 months, and/or 35 months after the attack.
What was found
The abstract reports directions of effect without numerical values: - The rate of forgetting for both flashbulb memories and event memories slowed after one year. - The content of flashbulb and event memories stabilized after one year. - Strong emotional reactions elicited by the event were remembered poorly, worse than non-emotional contextual details (such as where and from whom one learned of the attack).
Why it matters
This study provides evidence on the trajectory of long-term memory for major public trauma, indicating that memory decay slows and content stabilizes after a year, while emotional memory is notably less durable than contextual recall.
Limits
The abstract provides no numerical data, confidence intervals, or effect sizes. Participants completed surveys at various subsets of timepoints ("and/or 35 months"), raising potential attrition and selection bias across waves.