Count out your intrusions: Effects of verbal encoding on intrusive memories

Abstract

Peri-traumatic information processing is thought to affect the development of intrusive trauma memories. This study aimed to replicate and improve the study by Holmes, Brewin, and Hennessy (2004, Exp. 3) on the role of peri-traumatic verbal processing in analogue traumatic intrusion development. Participants viewed an aversive film under one of three conditions: counting backwards in 3s (“verbal interference”), verbalising emotions and thoughts (“verbal enhancement”), or without an extra task. A dual-process account of PTSD would predict that verbal interference would increase intrusion frequency compared to no task, whereas verbal enhancement would lead to a decrease. In contrast, mainstream memory theory predicts a decrease in intrusion frequency from any concurrent task that diverts attention away from the trauma film. The main finding was that the verbal interference task led to a decrease in intrusive memories of the film compared to the other two conditions. This finding does not support a dual-process account of PTSD, but is in line with general theories of memory and attention.

Keywords:

• Intrusive memories
• Post-traumatic stress
• Information processing
• Autobiographical memory

Acknowledgements

We would like to thank Anke Ehlers for lending us the road traffic accident clip, David G. Pearson for his helpful comments on our manuscript, all the students who helped with data collection, and Pieter van Groenestijn of the RTOG for technical support.