Role of thought-related beliefs and coping strategies in the escalation of intrusive thoughts: An analog to obsessive–compulsive disorder

Abstract

Cognitive–behavioral models of obsessive–compulsive disorder (OCD) assume that obsessions have their origin in normal intrusive thoughts. These models propose that certain beliefs, such as thought–action fusion (TAF) beliefs, combined with the use of ineffective coping strategies, such as thought suppression, lead to the development of OCD. The purpose of the current study was to examine the relationship between these variables in a non-clinical sample in addition to exploring the effects of an alternative, acceptance-based coping strategy. This study explored the relationship between TAF beliefs, thought suppression, and OC-consistent symptoms via mediational analyses. Results showed that thought suppression mediated the relationship between TAF beliefs and OC-consistent symptoms. This study also experimentally examined the effects of various coping strategies (suppression, acceptance, or monitor-only) on the frequency of a distressing intrusion and appraisal ratings (e.g., anxiety, guilt, responsibility) after a TAF induction. Spontaneous suppression in the monitor-only group made comparisons of the experimental data difficult. However, analyses provided preliminary evidence suggesting that thought suppression is related to more intrusions, higher levels of anxiety, and negative appraisals, whereas an acceptance-based approach may be a useful alternative. Additional findings, limitations of the current study, and directions for future research are discussed.

Introduction

Research suggests that 80–99% of persons in non-clinical samples experience intrusive thoughts (Freeston, Ladouceur, Thibodeau, & Gagnon, 1991; Purdon & Clark, 1993). Such thoughts are believed to play a role in the development and maintenance of a number of disorders including post-traumatic stress disorder and obsessive–compulsive disorder (OCD) (Ladouceur et al., 2000). There are many similarities between obsessions and intrusive thoughts in those without OCD. Both are similar in form, appraised negatively, related to particular mood state, and evoke similar coping strategies (Rachman & de Silva, 1978; Wang & Clark, 2002). Despite these similarities, recent findings suggest that non-clinical intrusive thoughts and obsessions in those with OCD may be distinguishable based on the abnormality of thought content (Rassin & Muris, 2006). Furthermore, obsessions are more frequent and intense, less acceptable to the individual, more strongly resisted and harder to dismiss, and more anxiety-provoking than non-clinical intrusive thoughts (Rachman & de Silva, 1978).

Cognitive–behavioral (CB) theories of OCD (e.g., Clark & Purdon, 1993; Purdon, 2001; Rachman (1993), Rachman (1997), Rachman (1998); Salkovskis (1985), Salkovskis (1989)) assume that obsessions have their origin in normal intrusive thoughts. These theories propose that cognitive factors, such as beliefs about intrusive thoughts, and maladaptive coping strategies lead to the escalation of intrusive thoughts. Thus, when a person holds certain beliefs and experiences an intrusive thought, he/she will become distressed, prompting the use of strategies to remove and/or prevent perceived consequences of the intrusion. These strategies are believed to be ineffective in the long run, in that they strengthen the belief that thoughts are dangerous, which leads to increased thought monitoring and saliency of cues related to the thought (Purdon & Clark, 2002; Salkovskis, 1998). This results in increased frequency of intrusions and distress.

A number of thought-related beliefs, such as thought–action fusion (TAF) beliefs, have been hypothesized to be involved in this escalation process. TAF involves beliefs that having an unacceptable thought is the moral equivalent of carrying out an unacceptable action (“moral TAF”) and thinking about an unacceptable event makes it more likely to happen (“likelihood TAF”) (Shafran, Thordarson, & Rachman, 1996). A number of studies using the Thought–Action Fusion Scale (TAF Scale; Shafran et al., 1996), a self-report measure containing moral and likelihood subscales, have found that persons with OCD score higher on the total and subscale scores than those without the disorder (Amir, Freshman, Ramsey, Neary, & Brigidi, 2001; Coles, Mennin, & Heimberg, 2001; Rassin, Merckelbach, Muris, & Schmidt, 2001). The relationship between the likelihood subscale and OC symptoms appears more robust, with moral subscale scores seeming to be related specifically to religiosity (Rassin & Koster, 2003).

Experimental studies have also examined TAF beliefs in relation to OC symptoms. Rachman, Shafran, Mitchell, Trant, and Teachman (1996) developed a method to experimentally induce TAF by having participants write out a distressing sentence (“I hope… is in a car accident”), fill in the blank with a friend or relative's name, and visualize the accident. Rachman et al. found this method successful in inducing high levels of TAF. Furthermore, this induction has been found to produce OC-like experiences (e.g., anxiety, guilt, urges to neutralize) even in non-clinical samples (e.g., Rassin, 2001; van den Hout, Kindt, Weiland, & Peters, 2002; van den Hout, van Pol, & Peters, 2001; Zucker, Craske, Barrios, & Holguin, 2002).

CB theories also view the use of ineffective coping strategies as a significant factor in the development and maintenance of OCD. In addition to correlational research showing a relationship between thought suppression tendencies and OCD severity (Muris, Merckelbach, & Horselenberg, 1996; Rassin & Diepstraten, 2003; Wegner & Zanakos, 1994), experimental studies have found that attempts to suppress neutral thoughts result in an increased frequency of intrusions while suppressing (“immediate enhancement effect”) (e.g., Clark, Ball, & Pape, 1991; Lavy & van den Hout, 1990; Wegner, Schneider, Carter, & White, 1987) and after suppressing (“rebound effect”) (e.g., Clark et al., 1991; Muris & Merckelbach, 1991; Wegner et al., 1987). However, the findings from studies using personal intrusive thoughts have been mixed, with some providing evidence for the immediate enhancement (Marcks & Woods, 2005; Salkovskis & Campbell, 1994; Trinder & Salkovskis, 1994) and rebound effects (Koster, Rassin, Crombez, & Naring, 2003; McNally & Ricciardi, 1996), and others finding no evidence of these particular effects (e.g., Belloch, Morillo, & Gimenez, 2004; Janeck & Calamari, 1999; Kelly & Kahn, 1994; Marcks & Woods, 2005; Purdon & Clark, 2001; Purdon, Rowa, & Antony, 2005). When studies have examined the impact of thought suppression on emotional variables, the findings clearly show that suppression of personal intrusive thoughts causes an increase in anxiety (Koster et al., 2003; Marcks & Woods, 2005; Purdon & Clark, 2001; Trinder & Salkovskis, 1994) and a worsening of mood (Purdon & Clark, 2001).

Although CB theories posit how certain beliefs and coping strategies may be involved in the escalation of intrusive thoughts, they do not provide empirical evidence for this process. The majority of research has been conducted on these variables in isolation, with only a handful of studies examining these variables in combination. Smári and Hólmsteinsson (2001) found that thought-related beliefs (either TAF or responsibility beliefs) and thought suppression mediate the relationship between intrusive thoughts and OC symptoms. In a similar study, multiple models were tested, with the best-fitting model being TAF leading to suppression, which resulted in more OC symptoms (Rassin, Muris, Schmidt, & Merckelbach, 2000).

To date, only one study (Rassin, 2001) has experimentally examined these relationships. In this study, participants underwent Rachman et al.'s (1996) TAF induction and were instructed to suppress or not suppress during a 5-min period. At the end of this period, they provided various ratings and were allowed to neutralize the thought. Results showed that suppression did not lead to increased anxiety or frequency of intrusions, higher ratings of perceived moral wrongness, or higher probability estimates. However, it should be noted that the non-suppression group tried to suppress to some degree, which may have masked the effects of instructed suppression. Furthermore, the design of the study did not allow for an examination of the potential negative after effects of suppression (i.e., rebound effects).

Although there is some evidence supporting a CB account of OCD, additional studies are needed. Furthermore, given the possible negative effects of suppression, it seems important to explore other approaches for coping with intrusive thoughts. One alternative is an acceptance-based approach, such as acceptance and commitment therapy (Hayes, Strosahl, & Wilson, 1999) and mindfulness-based cognitive therapy (Segal, Williams, & Teasdale, 2002). Acceptance-based approaches focus on increasing one's willingness to experience thoughts and feelings without avoiding or viewing them as being true. By altering the context from one in which thoughts are believed and acted upon, to one in which they are simply noticed, the negative impact of thoughts on an individual should be diminished. To date, only one study has compared suppression to an acceptance-based strategy in coping with intrusive thoughts, with results showing that an acceptance-based strategy led to a decrease in distress (Marcks & Woods, 2005). Additional research is needed replicating these findings.

The purpose of this study was to further examine the relationship between TAF, thought suppression, and OC-like experiences, in addition to exploring the effects of an acceptance-based approach. The first goal of this study was to test a mediational model in which it was hypothesized that the relationship between TAF beliefs (as measured by TAF Scale Likelihood subscale) and OC symptoms (Padua Inventory—Washington State University Revision; PI-WSUR; Burns, Keortge, Formea, & Sternberger, 1996) would be mediated by thought suppression (White Bear Suppression Inventory; WBSI; Wegner & Zanakos, 1994).

This study also sought to experimentally examine the effects of thought suppression, an acceptance-based technique (a metaphor), and monitor-only (control) after a TAF induction. It was hypothesized that the thought suppression group would demonstrate the immediate enhancement and rebound effects in terms of frequency of intrusion, the rebound effect in terms of anxiety, and more negative appraisals compared to the other groups. It was hypothesized that the acceptance group would demonstrate a larger decrease in anxiety over time and a greater willingness to re-experience the intrusive thoughts than the other groups.