The causal role of attentional control within depressive rumination
Thesis or dissertation
University of Exeter
Reason for embargo
To pursue publication of this research
Objectives: Due to a number of conceptual and methodological limitations, existing research has provided only equivocal evidence that deficits/biases in attentional control (AC) are causally implicated in depressive rumination and/or that Cognitive Control Training (CCT) can be used to remediate such vulnerabilities. By using a well-validated training task and ensuring adequate training exposure, the current study aimed to examine the hypothesis that daily CCT would reduce rumination and improve mood among participants with elevated ruminative disposition. Method: Using a multiple baseline design (MBD), eight high-ruminating university participants rated their daily levels of rumination and mood before and after the randomly-determined introduction of daily CCT, designed to enhance their level of AC. Daily ratings were compared before and after the introduction of CCT, using systematic visual analysis and randomisation tests for significance at the group level. Results: No evidence was found to support the hypothesis that daily CCT reduces rumination and/or improve mood. While participants improved in their performance within the CCT across the training period, there was no evidence of near- or far-transfer, visual analysis revealed no impact of the introduction of daily training, and all group-level analyses were non-significant (p ≥ .05). Conclusion: Despite addressing a number of conceptual/methodological concerns, the current study provides no further support for AC theories of rumination or the use of CCT-based treatments for depression. Such conclusions must be interpreted in light of other methodological limitations, however, including the use of a non-clinical sample and the use of MBD to detect delayed treatment effects.