Cognitive control of obsessional thoughts Jessica R. Grisham * , Alishia D. Williams School of Psychology, University of New South Wales, Sydney, NSW 2052, Australia article info Article history: Received 27 October 2008 Received in revised form 15 January 2009 Accepted 20 January 2009 Keywords: Thought suppression Rumination Obsessive-compulsive disorder abstract A defining characteristic of obsessive-compulsive disorder (OCD) is unsuccessful suppression of unwanted thoughts. Recent evidence of individual differences in ability to control intrusive thoughts may inform our understanding of failures of cognitive control associated with OCD symptomatology. The current study investigated characteristics of cognitive style that are potentially associated with OCD symptoms and may influence response to unwanted thoughts, including perceived ability to control thoughts and tendency to ruminate. Undergraduate students (N ¼ 166) completed self-report measures of OCD symptoms, perceived thought control, and ruminative thinking. They were then presented with a distressing target thought and completed a standard thought suppression paradigm. Correlational results indicated that, controlling for anxiety and depression, OCD symptoms were positively associated with rumination and inversely associated with perceived thought control ability. In addition, OCD symptoms were associated with higher levels of distress and greater spontaneous efforts to suppress the target thought during a baseline period, while perceived thought control ability predicted frequency of target thoughts during suppression. Finally, results of the experimental manipulation confirmed that participants instructed to suppress experienced more intrusions during the recovery period. Clinical implications and future directions are discussed. Ó 2009 Elsevier Ltd. All rights reserved. Introduction Thought suppression is considered to be an important strategy to regulate emotions (Gross, 2002) and is often used as a way to reduce distress associated with disturbing thoughts (Erdelyi & Goldberg, 1978). Although suppression is an understandable response, it may paradoxically increase the frequency of the thought (Wegner, Schneider, Carter, & White, 1987). Moreover, inability to suppress an unwanted thought may lead to feelings of failure (Wegner & Pennebaker, 1993) and negative mood (Purdon, Rowa, & Antony, 2005). The nature and effects of different strate- gies for cognitive control are critical to theoretical models of obsessive-compulsive disorder (OCD). Individuals with OCD expe- rience relentless intrusive thoughts that they try to suppress or neutralize. Their struggle with obsessions may be conceptualized as an inability to inhibit, or shift attention from, disturbing thoughts. Cognitive-behavioral models of OCD (Rachman, 1997; Salkovskis, 1985) posit that failed efforts to manage unwanted thoughts are pivotal in the escalation and persistence of the disorder. In the classic study on thought suppression, participants who were instructed to suppress thoughts of a white bear subsequently reported more white bear thoughts than individuals who had not been instructed to suppress (Wegner et al., 1987). Wegner proposed the ironic process theory to explain these findings. According to this theory, attempts to suppress thoughts involve two cognitive processes: the operating process, an intentional search for a dis- tractor thought, and the monitoring process, an automatic search for the target suppressed thought (Wegner, 1994). Because the automatic monitoring process searches for occurrences of the target thought, it paradoxically increases the accessibility of that thought to consciousness. The intentional operating process is capacity-limited, therefore its functioning is adversely affected by interfering cognitive tasks. The monitoring process, however, is not capacity-limited and is therefore unaffected by the introduction of a cognitive load (Rassin, Merckelbach, & Muris, 2000). Research has demonstrated that the asymmetry in functioning between the two processes can lead to increased suppression failures as well as a heightened ability to detect these failures when under cognitive load (Wegner & Erber, 1992). Many studies have attempted to replicate the white bear effect, usually with nonclinical undergraduate samples. Although several investigations have provided support for post-suppression rebound, some have found only partial support (e.g., Kelly & Kahn, * Corresponding author. Tel.: þ61 2 9385 3031; fax: þ61 2 9385 3641. E-mail address: jessicag@unsw.edu.au (J.R. Grisham). Contents lists available at ScienceDirect Behaviour Research and Therapy journal homepage: www.elsevier.com/locate/brat ARTICLE IN PRESS 0005-7967/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.brat.2009.01.014 Behaviour Research and Therapy xxx (2009) 1–8 Please cite this article in press as: Jessica R. Grisham, Alishia D. Williams, Cognitive control of obsessional thoughts, Behaviour Research and Therapy (2009), doi:10.1016/j.brat.2009.01.014