Dysfunctional Processes Underlying Unwanted Habits (PDF)

PDF hosted at the Radboud Repository of the Radboud University Nijmegen The following full text is a publisher's version. For additional information about this publication click this link. http://hdl.handle.net/2066/138592 Please be advised that this information was generated on 2022-06-27 and may be subject to change.  Dysfunctional Processes Underlying Unwanted Habits: Automatic and Controlled Processes in Problematic Eating Behaviour and Hair Pulling Disorder Joyce Maas  ISBN 978-94-6299-036-4 Cover Kapa65, Pixabay Lay-out Nikki Vermeulen, Ridderprint BV, Ridderkerk, The Netherlands Printed Ridderprint BV, Ridderkerk, The Netherlands © 2015 Joyce Maas All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording or any information storage or retrieval system, without prior written permission from the author.  Dysfunctional Processes Underlying Unwanted Habits: Automatic and Controlled Processes in Problematic Eating Behaviour and Hair Pulling Disorder Proefschrift ter verkrijging van de graad van doctor aan de Radboud Universiteit Nijmegen op gezag van de rector magnificus prof. dr. Th.L.M. Engelen, volgens besluit van het college van decanen in het openbaar te verdedigen op donderdag 19 maart 2015 om 10.30 uur precies door Joyce Maas geboren op 17 december 1984 te Breda  Promotor: Prof. dr. E.S. Becker Copromotoren: Prof. dr. G.P.J. Keijsers Prof. dr. M. Rinck Manuscriptcommissie: Prof. dr. J.I.M. Egger Prof. dr. T. van Strien Prof. dr. P.J. de Jong (Rijksuniversiteit Groningen)  TABLE OF CONTENTS PART 1 7 CHAPTER 1 Introduction 9 CHAPTER 2 Implicit action tendencies and evaluations in unwanted snacking 25 behaviour CHAPTER 3 The attraction of sugar: An association between body mass index 39 and impaired avoidance of sweet snacks CHAPTER 4 Changing automatic behaviour through self-monitoring: 55 Does overt change also imply implicit change? CHAPTER 5 Does a dieting goal affect automatic cognitive processes 69 and their trainability? PART 2 89 CHAPTER 6 The Self-control Cognition Questionnaire: 91 Cognitions in the maintenance of unwanted habits CHAPTER 7 Automatic cognitive processes in Hair Pulling Disorder and their 105 relationship with symptom severity CHAPTER 8 Targeting relapse after successful cognitive behaviour therapy for 121 Hair Pulling Disorder using cognitive bias modification CHAPTER 9 Summary and General Discussion 141 CHAPTER 10 Dutch Summary 157 REFERENCES 165 APPENDICES Acknowledgement 181 Short biography 185 Publications 187   PART 1   Chapter 1 General introduction   General introduction 1 11 When taking a walk through the woods it is easiest to just follow the main trail. This trail has been used for many years, feels comfortable, and is easy to walk on. However, you might decide to make a new trail to discover new and more beautiful areas of the forest. You notice that walking along this new trail is much more difficult than using the old main trail. You get tired faster because you might have to cut down trees and plants, and there might be some bumps, trunks, or other obstacles you have to avoid or climb. Next time you might therefore decide to stick to the old main trail. When you do this, the new trail will eventually disappear. If you do repeatedly choose to take the new trail instead, this trail will become easier to walk on, and will soon become your new default choice. Since you will not be using the old main trail anymore, trees and plants might start to grow there instead, and after some time the old main trail will become less and less visible. This metaphor serves to illustrates that it is difficult to change unwanted habitual behaviour. Many people suffer from unwanted habits, such as nail biting, skin picking, or hair pulling. Although most habits are not pathological, some people clearly suffer from their habit in a way that treatment is warranted. It is easy and it takes little effort or conscious attention to perform habitual behaviour. After all, habits occur without thinking and are often a result of years of ‘practice’. Resisting habitual behaviour is much more difficult. On the other hand, overruling habitual behaviour by practicing another behavioural route over and over again will eventually become more easy and more automatic. New behavioural ‘trails’ can be formed and can become the new default choice, but this process clearly takes time and effort. Until the new behaviour is the default choice, the chances of regular relapses into the old behavioural ‘trail’ are considerable. Many patients relapse after receiving successful cognitive behaviour therapy (CBT) for their unwanted habit, which obviously is a problem. Although CBT has proven to be effective to reduce habitual behaviour in the short-term, long-term effects are less stable. Certain processes underlying unwanted habitual behaviour seem to remain unaffected by CBT, resulting in the large relapse rates. The aim of the this dissertation is twofold. The main goal is to enhance our understanding of the underlying processes of unwanted habits. By finding out more about the underlying processes, we might be better able to understand why CBT is unsuccessful in changing habitual behaviour in the long-term. The second goal of this dissertation is to investigate how these underlying processes can be changed in order to contribute to solutions that can reduce these high relapse rates. The dissertation focuses on two unwanted habits in two different samples. The first part of this dissertation describes several experimental studies carried out in student samples focusing on eating behaviour and non-pathological snacking. The second part focuses on studies carried out in a patient sample suffering from trichotillomania (Hair Pulling Disorder). While the student studies primarily investigate underlying processes of unwanted habits, the main aim of the trichotillomania studies is to learn more about how relapse rates can be decreased. The present General Introduction starts by giving background information about unwanted habits, and more specifically about trichotillomania. The background information is followed by theoretical accounts that shed light on the underlying processes of unwanted habits and relapse. The third section explains why it is important to look at  Chapter 1 1 12 automatic aspects of behaviour from a dual process model perspective. Together, these three sections provide the theoretical context of this dissertation. This chapter concludes with a brief outline of the upcoming chapters. Background When screening a large sample of students (see Chapter 6), we found that 85 – 96% of students suffered from at least one unwanted habit. Often mentioned habits were skin picking, snacking, and smoking. Most people do not seek treatment for their unwanted habit. One example of a pathological habit is trichotillomania. Trichotillomania was categorized as an ‘impulse-control disorder not otherwise specified’ in the DSM-IV-TR (APA, 2000). In the DSM-5 (APA, 2013), trichotillomania is classified within the category ‘obsessive compulsive and related disorders’ and is referred to as ‘Hair Pulling Disorder’. To be consistent with this new classification, the term ‘Hair Pulling Disorder’ is used in the remainder of this chapter. People suffering from Hair Pulling Disorder (HPD) pull hair from their body until thinning of the hair or bald spots become visible. Approximately 80% of these patients pull hairs from their head. The other 20% pull hairs from eyelashes, eyebrows, or from other parts of their body. Approximately 40 – 50% of patients pull out hairs from multiple parts of their body (Christenson & Mansueto, 1999; Flessner et al., 2010). For almost half of the patients hair pulling involves pre- and post-pulling ritualized behaviours; hairs are not simply pulled and immediately discarded. Some people spend time playing with their hair first before pulling, stroking it or taking their time in (either consciously, semi-consciously or unconsciously) searching for a hair with a particular texture to pull. Some patients visually inspect hair before pulling, looking for asymmetry or hairs that are of a different colour. After pulling, some patients collect and order the hairs, and others might stroke the root against their lips or bite or eat the root (Duke, Keely, Geffken, & Storch, 2010; Grant & Odlaug, 2008). The lifetime prevalence rate of HPD, as diagnosed according to DSM-IV-TR criteria (APA, 2000) is estimated at 0.6% (Christenson, Pyle, & Mitchel, 1991). There has been a debate over the years as to whether the criteria regarding feelings of tension and relief should be included because many patients who pull hair on a daily basis do not recognize them. Therefore these criteria are no longer part of the DSM-5 HPD diagnosis. Lifetime prevalence of hair pulling without the DSM-criteria ‘feelings of tension prior to pulling and relief after pulling’ are estimated to be at 3.4% for women and 1.5% for men (Christenson et al., 1991). Up to date, the true prevalence of HPD is still unknown, however, since there have been no large-scale epidemiological studies so far. When reviewing the literature, Duke and colleagues (2010) found prevalence rates of hair pulling in college students varying from 1% to 13.3%. Although once thought to be a rare condition, HPD is rather common. Brief CBT is considered the treatment of choice for HPD (e.g., Keijsers et al., 2006b; Lerner, Franklin, Meadows, Hembree, & Foa, 1998; Van Minnen, Hoogduin, Keijsers, Hellenbrand, & Hendriks, 2003), as well as for other pathological unwanted habits. CBT shows excellent short-term results, better than other treatments, such as serotonin-based medication. However, results regarding long-term  General introduction 1 13 treatment effects are less consistent. Effect-size reductions up to 70% have been reported 24 months after treatment termination (e.g., Keijsers et al., 2006b). Relapse rates for other pathological habits and impulse-control disorders also tend to be high: for example, 92% for pathological gambling (Hodgins & el-Guebaly, 2004; Ledgerwood & Petry, 2006), 70 – 90% for smoking (Piasecki, 2006), and 60 – 70% for alcohol use disorders (Moos & Moos, 2006). A better understanding is needed of why habits are so resistant to change. The next section provides a brief discussion of theories that might explain the phenomenon we like to call the ‘dough effect’: Habitual behaviour is easy to knead into another form, but it retains a tendency to crawl back into its original shape. Over the years, many theories have tried to explain the ‘dough effect’. The next section explains why some of these theories evidently seem unfit to explain this phenomenon, whereas other theories might be able to give us more insight into the underlying processes of unwanted habitual behaviour and its resistance to change. Theoretical accounts of the ‘dough effect’ One of the leading researchers in the field of self-control is Roy Baumeister. According to Baumeister and colleagues (Baumeister, Heatherton, & Tice, 1994) self-control is effortful. They argue that three conditions have to be met in order to successfully exert self-control. First of all, there must be a standard; a limit, or clear and specific direction in which behaviour should be changed. For example, during CBT for HPD, the patient and therapist agree to the maximum number of hairs that the patient is allowed to pull during the upcoming week. Second, the behaviour has to be monitored, since for behavioural change to occur it is essential that people become aware of their own responses. Using a diary, HPD patients monitor the number of hairs they pulled and the time of the day the hair pulling occurred. Patients might also write down additional information, such as antecedent factors and thoughts accompanying the hair pulling. It is essential, according to Baumeister et al., that the changes in behaviour due to successfully exerting self-control are carefully monitored. It provides the person with necessary feedback on success of the change process. Third, a person must have enough resources to be able to change automated behaviour. Baumeister and others showed that these self- control resources are limited and can become temporarily depleted (e.g., Baumeister, Bratslavsky, Muraven, & Tice, 1998; Muraven Tice, & Baumeister, 2000). In one experiment, for example, hungry participants were presented with chocolate chip cookies, chocolates, and radishes (Baumeister et al., 1998). The chocolate chip cookies were freshly baked in the same room where the experiment took place, filling the whole room with a delicious aroma. One group of participants was allowed to taste the cookies and chocolates, but the other group was only allowed to taste the radishes. The participants who were not allowed to taste the cookies and chocolates were more likely to give up on a subsequent frustrating problem-solving task. Baumeister has called this phenomenon ‘ego- depletion’. Ego-depletion is closely related to the functions of executive control. People differ in their ability to use executive control. The term ‘ego-depletion’, more than executive control, emphasizes that executive control abates when multiple self-control tasks are executed.  Chapter 1 1 14 The first two conditions for successful self-control are readily recognizable in the typical components of CBT for unwanted habits: CBT helps patients to set standards or goals for the long- term (after treatment) as well as for the short-term (the next session). Further, careful monitoring of the unwanted behaviour during the day is a vital part of CBT (e.g., Hawton, Salkovskis, Kirk, & Clark, 2000; Keijsers et al., 2006a, 2006b). Monitoring is used to collect information about a patient’s symptom levels at the start of treatment, during treatment, and at treatment termination. Moreover, self-monitoring in itself produces beneficial reactive effects (see also Chapter 4); self-monitoring has been demonstrated to produce decreases in unwanted conditions or behaviours in, for example, nail biting (e.g., Adesso, Vargas, & Siddal, 1979; Vargas & Adesso, 1976), smoking (e.g., McFall & Hammen, 1971), high anxiety levels (e.g., Hiebert & Fox,1981), overweight (e.g., Bellack, Rozensky, & Schwartz, 1974) and bulimia nervosa (e.g., Dolhanty, 2005). Although the exact role of ego-depletion has not been systematically researched in the context of treatment, one could easily assume that Baumeister’s third condition of successful self-control might explain why patients relapse after treatment; patients’ resources for self-control are limited and eventually may be insufficient to resist the temptation (urge, craving) to give in, resulting in relapse because of ego-depletion. Many researchers question the relation between craving and relapse, however, since a direct causal link between craving and relapse has not been supported by research (see Drummond, 2001; Kassel & Shiffman, 1992). Overall, Baumeister’s research is highly useful for clinical practice, but there is no clear understanding of the role of ego-depletion in relapse in the context of treatment. Thus far, ego-depletion has been established in laboratory settings and within short time frames: the effects of several consecutive self-control tasks in periods of minutes to an hour. There is a lack of research focusing on prolonged (days, weeks) effects of ego-depletion. Further, from clinical experience we know that, quite regularly, patients who completely stopped their hair pulling behaviour for weeks or months suddenly relapsed, sometimes to their own surprise, without having experienced a constant or a frequent urge to pull hair after they had stopped. Not only had their hair pulling stopped, their urge had disappeared as well (Keijsers et al., 2006b). Such reports are inconsistent with the concept of ego-depletion. Other theories might give us more insight into the reasons why patients relapse. Apart from Baumeister’s work, another classical view on the maintenance of unwanted habits and on regaining self-control stems from learning theory (see Mansueto, Stemberger, Thomas, & Golomb, 1997): Certain stimuli, external as well as internal, elicit the urge to pull hair. For example, a person may have developed a pattern of pulling hair when sitting alone in front of the TV when it is late at night and when feeling tired. The stimuli ‘being alone’, ‘watching TV’, ‘late at night’, and ‘feeling tired’ have become associated with hair pulling via classical conditioning. In addition, these stimuli or the urge to pull hair may have been associated with automatic beliefs that the person is unable to refrain from hair pulling. When one or more of these stimuli are present, the person is likely to start pulling hair. Furthermore, as a result of operant conditioning, hair pulling develops into a recurrent pattern, because hair pulling is rewarded by feeling comfortable or relaxed due to giving in to the habit. These