Do intrusive memory characteristics predict depression at 6 months?

Abstract

Two prospective studies have investigated whether the presence, intrusion, and avoidance of negative intrusive memories predict depression, and have reported conflicting findings. We aimed to replicate and extend these investigations by exploring the role of intrusion and avoidance of intrusive memories, as well as memory characteristics, in the prediction of depression prospectively. At Time 1 a mixed sample of community participants (N=85) were interviewed and completed self-report measures of depression, anxiety, and intrusive memory features. At Time 2 (6 months later, N=64) depression and anxiety symptoms were reassessed. Results were partly consistent with hypotheses for the sub-sample of participants who did not receive treatment between the baseline and follow-up assessments. Baseline levels of intrusion and some memory features (uncontrollability, distress, interference, numbness, detachment) predicted follow-up depression, controlling for baseline depression symptoms. Unexpectedly, avoidance of intrusive memories and other features (e.g., here and now quality) did not predict depression. Levels of intrusion and avoidance did not predict anxiety at follow-up. These results provide further evidence that intrusive memories are not simply an epiphenomenon of depression, but predict depression prospectively. Our results suggest that novel, depression-specific theories that emphasise the role of memory disturbances in the maintenance of depression are needed.

Keywords:

• Depression
• Anxiety
• Intrusive memories
• Memory
• Prospective study

Acknowledgements

We are grateful to Alishia Williams for assistance with data collection. This study was supported by an Australian Postgraduate Award scholarship awarded to Jill Newby, and received some support from Discovery Project grant (DP0984791) from the Australian Research Council awarded to Michelle Moulds.

Notes

¹The results presented here are part of a larger investigation exploring the role of intrusive memories in depression. The mixed sample of participants included three groups of participants; never-depressed, recovered, and clinically depressed groups. Please refer to Newby and Moulds (2010, 2011) for more extensive detail regarding baseline levels of intrusive memory variables, and comparisons between these groups at baseline.

²A total of 36 participants were excluded from the initial sample. Exclusion criteria included PTSD, sub-threshold PTSD symptoms, history of mania or hypomania, psychotic symptoms, alcohol and/or substance use disorders. For more extensive information regarding excluded individuals see Newby and Moulds (2010).