|University of New South Wales
|Faculty of Science
|Traumatic Stress; Controllability; Perceived Control
|Full text PDF:
This program of research investigated the effect of lacking control over negative situations on psychological functions involved in psychopathology. Controllability over various aversive stimuli was manipulated in healthy student participants. Studies 1 and 2 explored the impact of controllability on autobiographical memory. Study 1 found that lacking perceived control led to the retrieval of more categoric memories. Study 2 confirmed this finding and found that the effect of controllability on retrieval specificity was associated with limited executive resources. Study 3 examined the impact of controllability on future-related cognitive functioning. Participants who were led to believe they had no control subsequently imagined future events that were characterised by themes of impoverished mastery. These participants also demonstrated impaired social problem-solving. Studies 4-6 investigated the impact of controllability on distress tolerance. Study 4 found no effect of controllability on the ability to tolerate subsequent physical distress assessed by a cold pressor task. In Study 5, participants who did not previously have control subsequently reported a greater increase in anxiety following a secondary cognitively distressing task. However, this did not translate to a higher tendency to terminate the task earlier. Study 6 showed that lacking control led to more avoidance in response to a subsequent emotionally distressing task. Study 7 investigated the effect of lacking and losing control on hypervigilance. Unexpectedly, attentional and interpretation bias towards threat remained unaffected by the manipulation of controllability. Finally, Study 8 examined the effect of lacking and losing control on a physiological index of emotion regulation, heart rate variability. Participants who had lost control during the aversive stimulation exhibited a greater decrease in heart rate variability during the recovery period from the stressing task, reflecting poorer emotion regulation. No difference was found between participants who kept control the whole time and those who never had control. Overall, this program of research provides experimental evidence for the critical role of stressor controllability on different cognitive, emotional, behavioural, and physiological processes, and in doing so sheds light on a critical determinant on some of the core mechanisms implicated in traumatic stress.