Obsessive Compulsive Disorder

Graham Davey, Suzanne Dash, Frances Meeten

• Publisher: Bloomsbury Academic
• Year: 2014
• Print ISBN: 9781137308689
• eBook ISBN: 9781350312456
• Edition: 1
• Topic: Psychology
• Subtopic: Clinical Psychology
• Index: Psychology

Obsessive compulsive disorder is a disabling and distressing mental health problem. This accessible introduction examines OCD's causes, symptoms, diagnosis and treatment, and is richly illustrated with case studies, making it engaging reading for anyone wishing to understand this complex mental health problem.

Section Two

What Causes OCD?

4 Cognitive Factors

5 Behavioural, Psychodynamic and Social Factors

6 Biological Models of OCD

Preface

The second section examines theories that have been proposed to explain why individuals develop OCD. Chapter 4 covers cognitive accounts of OCD, and as you will see, many different theories fall under ‘cognitive accounts’. Cognitive processes, such as biases in memory, attention and interpretation are covered in this chapter, as well as cognitive models including memory deficits, thought suppression, inflated responsibility, thought-action fusion, intolerance of uncertainty, metacognitive therapy and the mood-as-input theory. In Chapter 5, we review explanations of OCD that come from behavioural, psychodynamic and sociocultural theories. In the behavioural section, the importance of conditioning, safety behaviours, and avoidance in the development and maintenance of OCD is presented. In the psychodynamic section, Freud’s psychoanalytic theory of psychopathology is covered, with particular focus on unconscious conflicts and defence mechanisms. Freud’s theory is illustrated with ‘The Rat Man’ case history. The final section of Chapter 5 examines cultural factors related to OCD, including religion and disgust. In Chapter 6, the biological accounts of OCD are discussed. These include biochemical, genetic, neuroanatomical, immunological and evolutionary accounts. Section 2 ends with an overall evaluation of the accounts of OCD covered in Chapters 4–6.

Chapter 4

Cognitive Factors

Obsessive and intrusive thoughts occur both in the general population and in those with OCD (Rachman & de Silva, 1978). However, it is the way that the thoughts are interpreted and appraised that is thought to underlie the distress experienced by individuals with OCD. In this section we will consider cognitive factors that are known to lead to an anxious interpretation of unwanted intrusive thoughts. The first part of the section will consider cognitive biases and the second will examine cognitive models of OCD.

Cognitive biases in OCD

Cognitive biases are a tendency to selectively process information, leading to a skewed representation of events and can be considered to be maladaptive structures or schemas that affect the way information is processed. Cognitive biases are a feature of many psychological disorders relating to anxiety (e.g. OCD and GAD (Generalised Anxiety Disorder)) and depression. In OCD cognitive biases are thought to result in the individual giving increased information processing resources to threat-relevant information. Preferential processing of information has been observed in a number of cognitive processes in OCD. Some of the most commonly researched cognitive biases in OCD are attentional biases, interpretation biases and memory biases. Evidence for each type of bias in OCD will be discussed below.

Memory biases

One way in which anxiety is maintained in individuals with OCD is through experiencing heighted or improved memory for threatening stimuli as compared to non-threatening stimuli. For example, individuals with contamination fear, OCD may be more likely to recall information about potentially contaminating objects than about neutral objects. If that threat-relevant material is more easily available, this may influence the number of intrusions an individual has, which can make people feel more threatened, thus heightening the need to perform compulsions. An early example of memory biases in recall was demonstrated by Bower, Monterio & Gilligan (1978) who found that when participants learnt word lists while in a negative mood, they recalled more of those word lists when also in a negative mood than when in a positive mood. However, while there are many studies on memory biases across the anxiety disorders (many of which have conflicting results; see Coles & Heimberg, 2002 for a review), there are relatively few studies on memory biases in OCD. Wilhelm, McNally, Baer & Florin (1996) examined explicit memory biases in OCD by asking individuals with OCD or a non-anxious control group to either remember or forget (known as a directed forgetting paradigm) neutral, negative or positive words. The authors found that while they replicated the standard finding in this type of task where participants recalled more ‘remember’ words than ‘forget’ words, participants with OCD had greater difficulty forgetting negative forget words as compared to positive and neutral forget words, than the control group did. These findings suggest that individuals with OCD encode negative words more elaborately than positive or neutral words, regardless of the instructions they were given. This study was replicated and extended by Tolin, Hamlin & Foa (2002). In the replication they found support for the findings of the previous study where participants with OCD were less likely to forget negative words. Tolin et al. (2002) also extended the study to include OCD relevant words and they found that the relevance of the word to OCD was more important than its positive or negative valency. This means that individuals with OCD had more difficulty forgetting OCD relevant words, regardless of whether these words were negative or positive. One possible explanation for this is that positive OCD words may still be relevant to a general feeling of threat and individuals may be using more elaborate encoding for threat relevant words regardless of the valency of that word.

While studies such as those reported above support the existence of memory biases in OCD, other published studies have not found support for this. For example, Foa, Amir, Gershuny, Molnar & Kozak (1997) examined explicit and implicit memory biases in OCD and found an implicit memory bias for threat in individuals with and without OCD. To further clarify the role of memory biases in OCD, Radomsky & Rachman (1999) proposed to examine memory biases in individuals who were sensitive to specific threats, in this case contamination fear. They believed that examining individuals who had specific contamination threats would clarify the existence of memory biases in OCD as these specific contamination fears should be accompanied by specific associations and the increased strength of these specific associations could be the essential factor in producing the memory bias. Radomsky & Rachman (1999) examined memory biases for contamination relevant objects in individuals with OCD (who expressed fear of contamination) as compared to anxious individuals (who did not have OCD) and a non-anxious control group. When looking at behavioural responses to clean and dirty objects, they found that the OCD group and the two control groups were more anxious about touching dirty objects than clean ones, but the OCD group were more anxious about touching any objects (clean or dirty) than the anxious control group and the anxious control group was more anxious about touching objects than the non-anxious control group. However, interestingly, only individuals with OCD had a biased memory for objects perceived as dirty as compared to clean (as evidenced by their being able to recall more contamination relevant items from a list than clean items), while the other control groups did not. Importantly, overall recall ability was no different in the OCD group as compared to the two control groups, rather the OCD group had an explicit memory bias for preferential recall of dirt related objects. In fact, participants were able to remember dirty objects better than clean ones, without being able to remember which objects were clean or dirty. This led the authors to suggest that the threat observed by the participants was not the dirty object, but the dirt itself. As such, those who remembered which objects were dirty without remembering what the contaminated object was, were showing an implicit memory bias towards remembering threatening material. To further clarify the existence of memory biases in OCD, Radomsky & Rachman (2004) examined studies that either, showed or failed to show, memory biases in OCD. They concluded that in studies where ecological validity was low, they were unlikely to reliably detect a memory bias in OCD. Radomsky and Rachman suggested that experimental paradigms should have significance and relevance to individuals with OCD.

Attentional biases

An attentional bias involves showing preferential attention towards, or selectively attending to, threatening or anxiety provoking information, relative to neutral information. Attentional biases are important in both the development and maintenance of OCD. For example, being more attentive to threatening material may mean that intrusions are interpreted as being threatening and having a heightened attention to threat-relevant information may make one more likely to perform compulsions to seek anxiety reduction. According to Cisler & Koster (2010), attentional biases can be observed through three key characteristics: a) facilitated attention (e.g. detecting threat stimuli faster than non-threat stimuli), b) difficulty in disengagement (e.g. it is more difficult to disengage attention from threat stimuli compared to non-threat stimuli), and c) attentional avoidance (e.g. attention is allocated to locations opposite to the location of a threat) (Cisler & Koster, 2010). However, evidence for attentional biases in OCD is inconsistent and evidence both supporting and disconfirming the role of attentional biases in OCD will be discussed in this section.

In order to examine attentional biases in OCD, one strategy has been to examine attentional biases relevant to OCD specific threats such as biases towards contamination stimuli. One technique used by researchers (e.g. Foa & McNally, 1986) is the dichotic listening task. In this study a different stream of information was presented to each ear at the same time, but participants were instructed to concentrate only on one stream of information. Using this task, researchers found that individuals with OCD were better at detecting fear-relevant words that were presented in the information that they were not attending to than non-threat words presented in the non-attention ear. Furthermore, after the OCD group received a therapeutic intervention in the form of exposure response prevention treatment, this difference in ability to detect threat over non-threat words disappeared. This enabled the authors to conclude that threat relevant attention biases in OCD could be manipulated and could thus be diminished with treatment. Although attentional biases are well documented in anxiety disorders, OCD researchers have focused on content specific attentional biases (you will remember from the section above that this is also the case with memory biases), meaning that individuals with OCD and specific contamination fear showed a bias towards threatening material only when it was relevant to contamination, but not when it was relevant to other types of anxiety such as social anxiety (Tata, Leibowitz, Prunty, Cameron & Pickering, 1996). These findings indicate that biases in OCD are not a response to a general feeling of anxiety, but are specific to threats associated (in this case) with contamination fear specific OCD.

As noted above there are three core components of attentional biases (facilitated attention, difficulty in disengagement, attentional avoidance). One way to unpick the role of attentional biases in OCD is to examine which components can be observed in individuals with OCD. Cisler & Olatunji (2010) examined core components of attentional biases in contamination fear (CF). CF was chosen because it is a subtype of OCD that is associated with strong evidence for attentional biases. In CF they found that attentional biases were characterized by individuals having difficulty disengaging from threat and they suggested that this may be due to individuals with CF being unable to remove attention from sources of threat, or that they purposefully maintain attention onto threat because they perceive threat-relevant stimuli as harmful.

Although attentional biases in anxiety disorders are well documented, more recently researchers have reported inconsistencies in findings relating to attentional biases in OCD (e.g. Moritz et al., 2008; Moritz & von Muhlenen, 2008). Moritz and colleagues have pointed out that there are a number of published articles which did not find evidence for attentional biases in OCD and they present experimental data looking at attentional biases in a Stroop task (Moritz et al. 2008) and examining attention towards and ability to disengage from OCD relevant stimuli (Moritz & von Muhlenen, 2008). In both cases the authors concluded that there was no evidence to indicate that participants with OCD demonstrated attentional biases. However, Amir, Najmi & Morrison (2009) have suggested that the lack of evidence for attentional biases in OCD in these studies could be accounted for by taking into account the possibility that the attentional bias may actually diminish over the course of the experiment. When Amir et al. (2009) examined attentional biases in individuals with OCD over a number of time points, they observed that the bias diminished after the first block of trials, which they suggest may mean that individuals are habituating to the perceived threat over time. As many attentional bias experiments have used differing numbers of trials on experiments of differing lengths, this may explain the inconsistencies in research findings.

Interpretation biases in OCD

An interpretation bias occurs when an ambiguous event or situation is interpreted as a threat. Interpretation biases are a central cognitive processes in OCD and Rachman (1997) proposed that a key difference between a ‘normal obsession’ and a ‘clinical obsession’ is the interpretation of the significance of the obsession. A key characteristic of OCD is that individuals will make a catastrophic interpretation of an intrusive thought. In terms of OCD symptoms this anxiety-relevant interpretation may make an individual interpret an intrusion as being threatening, which in turn will increase anxiety and also increase the desire to perform compulsive behaviours. Studies of the interpretation biases that drive this catastrophic interpretation response have focused on various aspects of interpretation such as a perception of inflated responsibility for harm in ambiguous situations, or the tendency to view a thought as the same as an action (thought-action fusion). These different aspects of interpretation have been given a central role in cognitive models of OCD (Rachman, 1997; Salkovskis, 1985) and will be di...

Table of contents

• Cover
• Title page
• Copyright
• Contents
• List of Figures and Tables
• Acknowledgements
• Publisher’s Acknowledgements
• About the Authors
• Note from Series Editors
• Reading Guide
• Preface
• Section One: What is OCD?
• Section Two: What Causes OCD?
• Section Three: How Do We Treat OCD?
• Epilogue
• Glossary
• References
• Index