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J. Behav. Ther. & Exp. Psychiat. 44 (2013) 396e403

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Journal of Behavior Therapy andExperimental Psychiatry

journal homepage: www.elsevier .com/locate/ jbtep

Can concreteness training buffer against the negative effects ofrumination on PTSD? An experimental analogue study

Anja Schaich a, Edward R. Watkins b, Thomas Ehring a,c,*

aDepartment of Clinical Psychology, University of Amsterdam, Weesperplein 4, 1018 XA Amsterdam, The NetherlandsbMood Disorders Centre, School of Psychology, University of Exeter, EX4 4QG, UKc Institute of Psychology, University of Münster, Fliednerstr. 21, 48149 Münster, Germany

a r t i c l e i n f o

Article history:Received 9 October 2012Received in revised form21 February 2013Accepted 27 March 2013

Keywords:TraumaPTSDRuminationProcessing modeAbstract thinkingConcrete thinking

* Corresponding author. Institute of Psychology, Unerstr. 21, 48149 Münster, Germany. Tel.: þ49 251 83

E-mail address: thomas.ehring@uni-muenster.de (

0005-7916/$ e see front matter � 2013 Elsevier Ltd.http://dx.doi.org/10.1016/j.jbtep.2013.03.006

a b s t r a c t

Background and objectives: Trauma-related rumination has been found to be an important maintainingfactor for PTSD. On the background of the processing mode account of ruminative thinking, this studytested whether the relationship between rumination and analogue PTSD symptoms can be modified bytraining participants in a concrete mode of processing.Methods: Healthy participants were trained in either an abstract or a concrete style of processing. Af-terwards, they watched a stressful film. The interactive effect of training condition and trait ruminationon intrusive memories of the film was examined.Results: Following abstract training, a positive relationship between trait rumination and intrusivememories of the film emerged. As hypothesized, this relationship disappeared following concretetraining.Limitations: include the lack of a no-training control group and the analogue paradigm used.Conclusions: The study provides preliminary evidence that the relationship between trait rumination andanalogue PTSD symptoms can be modified. If replicated in future studies, it may be promising to examinethe value of concreteness training for prevention and/or treatment of PTSD.

� 2013 Elsevier Ltd. All rights reserved.

1. Introduction

Trauma survivors with posttraumatic stress disorder (PTSD)report frequent ruminative thoughts related to the trauma and/orits consequences, e.g., “Why did it happen to me” or “What if I haddone something differently” (Michael, Halligan, Clark, & Ehlers,2007). Cognitive theorists have suggested that trauma-relatedrumination is not merely an epiphenomenon of suffering fromPTSD, but that rumination is causally involved in the maintenanceof the disorder (Ehlers & Clark, 2000; Wells & Sembi, 2004).

1.1. Trauma-related rumination as a maintaining factor of PTSD

Evidence supporting the view that trauma-related ruminationmaintains PTSD comes from three groups of studies. First, resultsfrom a series of cross-sectional studies show that self-reportedrumination is associated with PTSD symptom severity as well as a

niversity of Münster, Flied-34151.T. Ehring).

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diagnosis of PTSD (e.g., Ehring, Frank, & Ehlers, 2008; Michael et al.,2007; Moore, Zoellner, & Mollenholt, 2008). Second, ruminationhas been found to predict future PTSD in prospective longitudinalstudies (e.g., Ehring et al., 2008; Kleim, Ehlers, & Glucksman, 2007;Michael et al., 2007). Importantly, rumination still predicted futurePTSD when initial symptom levels were statistically controlled(Ehring et al., 2008; Kleim et al., 2007; Michael et al., 2007).

Finally, the hypothesis that rumination is causally involved inthe maintenance of PTSD symptoms was tested in a number ofexperimental studies. Several studies have used the trauma filmparadigm, in which healthy participants are exposed to a distress-ing film. Extensive research has shown that this analogue paradigmreliably induces analogue PTSD symptoms, especially intrusivememories, in healthy participants (Holmes & Bourne, 2008;Weidmann, Conradi, Gröger, Fehm, & Fydrich, 2009). In a series ofstudies using this paradigm, rumination and/or worry has beenshown to lead to significantly more analogue PTSD symptoms and/or a significantly slower emotional recovery from the film than thecontrol conditions (Ball & Brewin, 2012; Wells & Papageorgiou,1995; Zetsche, Ehring, & Ehlers, 2009). These findings were repli-cated in a recent study, in which rumination about real-life trau-matic or distressing experiences was induced (Ehring, Fuchs, &Kläsener, 2009).

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1.2. How can functional and dysfunctional types of rumination bedistinguished?

In sum, there is extensive evidence supporting the view thattrauma-related rumination is dysfunctional. However, repeatedand prolonged thinking about a traumatic experience can also behelpful (e.g., Calhoun, Cann, Tedeschi, & McMillan, 2000; vanEmmerik, Kamphuis, & Emmelkamp, 2008). How can the func-tional versus dysfunctional effects of rumination be explained?

Watkins (2008) suggested that the effects of repetitive thinkingare at least partly due to the style or mode of processing an indi-vidual adopts during repetitive thought. Specifically, dysfunctionalrumination is thought to be characterized by abstract, i.e. high-level,general, decontextualized, analytical, and evaluative processing(e.g., “Why did it happen?”) focused on negative content. On theother hand, more functional forms of repetitive negative thinkingare characterized by concrete, i.e. low-level, specific, non-evaluative,and experiential, processing (e.g., “How did it happen?”). The pro-cessing mode account is supported by studies investigating rumi-nation in depression and worry in generalized anxiety disorder(GAD). In correlational studies, the degree of abstract thinking hasbeen shown to be related to diagnoses of GAD and depression(Stöber & Borkovec, 2002; Watkins & Moulds, 2007). Furthermore,results froma series of experimental studies showthat the inductionof abstract thinking, but not that of concrete thinking, leads toincreased emotional reactivity, reduced emotional processing andincreased negative self-evaluation (e.g., Moberly & Watkins, 2006;Watkins, 2004; Watkins, Moberly, & Moulds, 2008).

There is preliminary evidence showing that the processingmode theory also applies to trauma-related rumination. In twosamples of road traffic accident survivors, the combination of thefrequency and abstractness of ruminative thinking predicted PTSDbetter than rumination frequency alone (Ehring et al., 2008). In arecent experimental study, the induction of abstract processingabout negative life events led to significantly more intrusivememories about the event than concrete processing about the samecontent (Santa Maria, Reichert, Hummel, & Ehring, 2012). Similarly,using the trauma film paradigm, Ehring, Szeimies, and Schaffrick(2009) found that the induction of abstract rumination about atrauma film led to a significantly slower recovery from the film thanconcrete thinking and distraction.

1.3. How can the negative association between rumination andPTSD be influenced?

Given the strong relationship between rumination and PTSD, itappears highly relevant from a clinical perspective to find ways inwhich this association can be influenced. One approach could be touse interventions aimed at reducing the frequency of rumination.However, the processing mode theory described above suggeststhat an alternative approach may also be promising. Rather thanaiming to influence individuals’ general tendency to repetitivelythink about their trauma, interventions could instead be focused onchanging the mode or style of thinking that individuals adopt.Specifically, the processing mode theory predicts that trainingparticipants to adopt a more concrete mode of processing shouldreduce the dysfunctional effect of their repetitive thinking.

Empirical support for this hypothesis comes from an experi-mental study conducted by Moberly and Watkins (2006). The au-thors randomly assigned healthy participants to one of twoconditions. In one condition, participants were trained to thinkabout a number of scenarios in an abstract way, whereas partici-pants in the other condition were trained in concrete processingusing the same scenarios. Results showed that following the trainingin abstract processing, the general tendency to ruminate assessed by

a trait rumination questionnaire significantly predicted partici-pants’ emotional response to a failure task later in the session.Crucially, this relationship disappeared in the concrete trainingcondition. That is, the training conditionmoderated the relationshipbetween rumination and subsequent emotional response to astressor. In sum, these results suggest that training in concreteprocessing can indeed buffer against the negative effects of rumi-nation on emotional vulnerability to subsequent stressful events.

The current studyaimed to replicateMoberlyandWatkins’ (2006)findings in the context of an analogue traumatic stressor, and therebyto further extend our understanding of the impact of processingmode on PTSD symptoms. Prior studies demonstrated that inducinga concrete processing mode following exposure to an analoguestressor (traumafilm)hastened recovery relative to an abstractmode(Ehring, Szeimies et al., 2009). The current study sought to testwhether processing mode adopted prior to exposure to a traumaanalogue would moderate the effect of trait rumination on intrusivememories. This change in methodology enables a cleaner test of thecausal effect of processing mode, further delineates the conditionsunder which processing mode may influence PTSD symptoms, andprovides a proof-of-principle test of whether adopting a concretemode may serve a protective or preventive function. Healthy par-ticipantswere first trained in either an abstract or a concretemode ofprocessing, and then watched a stressful film. It was hypothesizedthat trait ruminationwill be positively related to the number, vivid-ness, and distress of intrusive memories about the film followingtraining in abstract thinking, but not significantly related to intrusivememories following training in concrete thinking. In exploratoryanalyses, we testedwhether these findings extend to negativemoodand physiological arousal triggered by the film.

2. Method

2.1. Participants

Sixty-eight female students participated in the study. For ethicalreasons, exclusion criteria were past traumas, past or present psy-chiatric disorder, current suicidal ideation, current self-injuriousbehaviour, or a BDI-II score greater than 10. Two participantsindicated that they looked away or closed their eyes a lot of the timewhile watching the stressful film and these participants weretherefore excluded from the analyses. The final sample consisted of66 participants (100% female; age: M ¼ 20.05, SD ¼ 2.74).

2.2. Materials and tasks

2.2.1. Analogue stressorA scene from a motion picture (‘Irreversible’, rated 16þ) lasting

14min and showing the raping and beating of awomanwas used asan analogue stressor (for earlier studies using this scene, seeVerwoerd, De Jong, & Wessel, 2008; Verwoerd, Wessel, de Jong, &Nieuwenhuis, 2009; Weidmann et al., 2009).

2.2.2. Pre-film processing manipulationBefore watching the film, participants were randomly assigned

to either an abstract or a concrete processing condition. In order toinduce the different types of processing, the paradigm developedby Moberly and Watkins (2006) and Watkins et al. (2008) wasadapted for use in the current study. Participants were presentedwith 15 positive and 15 negative scenarios, each approximatelythree sentences long (for a detailed description of the developmentof the training material, see Watkins et al., 2008).

An example of a negative scenario is as follows:

You have an argument with your best friend. You have only had afew minor disagreements in the past, but this argument becomes

A. Schaich et al. / J. Behav. Ther. & Exp. Psychiat. 44 (2013) 396e403398

heated and she tells you that she feels that she will never be able totrust you again. You are shocked and hurt.

An example of a positive scenario reads as follows:

You go for a job interview. You are well prepared and able toanswer the questions competently. The interview panel is friendlyand encouraging, and you leave feeling very confident that youhave performed well enough to secure the position

Scenarios were presented on a computer screen for 20 s each,alongwith an instructiononhowtoprocess the scenario. Participantswere then asked to think about each scenario for 1 min according tothe instruction. After 1min, thenext scenarioappearedon the screen.

Instructions on how to process the scenarios differed betweenconditions. Participants in the abstract conditionwere instructed asfollows:

Please concentrate on this event for the following minute. Thinkabout why it happened and analyze the causes, meanings, andimplications of this event.

Participants in the concrete condition were instructed asfollows:

Please concentrate on this event for the following minute. Focus onhow it happened and imagine it in your mind as vividly andconcretely as possible, like a ‘movie’ about how this event unfolded.

At the beginning of the processingmanipulation, all participantsreceived one negative scenario to practice the processing instruc-tion for 1 min and received feedback from the experimenter.

2.2.3. Manipulation checkIn line with Watkins et al.’s (2008) study, one of the interper-

sonal vignettes (“A disagreement with your boss”) from the MeansEnds Problem Solving task (MEPS) (Platt & Spivack,1972) was used tocheck whether the scenario training phase successfully induced theintended abstract versus concrete processing style. Participantswere asked to generate the ideal strategy to overcome the problemsituation. Each participant’s solution was audio-recorded and laterscored by a judge who was unaware of the condition. Ratings werebased on the Stöber and Borkovec (2002) abstract-concrete scale(1 ¼ ‘abstract’, 2 ¼ ‘somewhat abstract’, 3 ¼ ‘neither-nor’,4 ¼ ‘somewhat concrete’, 5 ¼ ‘concrete’). Solutions generated by arandom sample of 15 participants (22%) were additionally scoredby an independent rater (intraclass correlation coefficient ¼ 0.80).

In addition, participants filled in a short manipulation checkquestionnaire assessing (1) the degree to which participants wereable to concentrate on the scenarios (0e10 scale), (2) the degree towhich they thought about unrelated topics during the trainingperiod (0e10 scale), (3) howclear the scenarios were to them (0e10scale), and (4) the degree to which they would describe theirthinking about the scenarios as verbal versus characterized byimagery (scale from 0 ¼ mostly verbal to 10 ¼ mostly imagery).

2.2.4. Exposure to reminders of the analogue stressorIn order to trigger intrusive memories of the film, participants

were exposed to nine still pictures (10 s each) that had been takenfrom the film scene.

2.3. Dependent variables

2.3.1. Intrusive memories during the sessionThe number and characteristics of intrusive memories related to

the analogue stressor were measured using the Intrusions Question-naire (Ehring, Fuchs et al., 2009; Santa Maria et al., 2012). The In-trusions Questionnaire always followed a 3 min assessment of

resting heart rate and skin conductance. Participantswere instructedto fill in the questionnaire with regard to intrusive memories of thefilmthat cameto theirmindduring this3minassessmentperiod. Thequestionnairewasfilled in twiceduring thesession, after thefilmandafter the exposure to the reminders of the stressor. On the IntrusionsQuestionnaire, participants indicated (a) the number of intrusivememories regarding the film during the period of interest, (b) thevividness of these memories (0e100 scale), and (c) the level ofdistress related to the intrusions (0e100 scale). In the current study,the total number of intrusive memories reported during the session,the mean vividness, and mean distress ratings provided during thesession were each used as dependent variables. These scoresincluded both intrusivememories experienced directly after thefilmas well as those experienced after exposure to the film reminders.

2.3.2. Intrusive memories following the sessionIn order to assess intrusive memories about the film during the

week following the session, participants were asked to fill in theIntrusions Questionnaire on the evening of each of the 7 daysfollowing the experiment. The instruction of the questionnaire wasslightly changed and now referred to the total number of intrusivememories experienced on the respective day. The total number ofintrusive memories reported during the week, the mean vividness,and mean distress ratings (across the week) were used as depen-dent variables.

2.3.3. Mood during the sessionThe Positive and Negative Affect Schedule (PANAS) (Watson, Clark,

& Carey, 1988) was used to assess participants’ mood at five timepoints during the session. Only the subscale assessing negativemood was included in the analyses.

2.3.4. Mood following the sessionParticipants were asked to fill in the PANAS again on the evening

of each of the 7 days following the experiment. Participants wereasked to fill in the PANAS with regard to their mood on therespective day.

2.3.5. Physiological arousalHeart rate (HR) and skin conductance (SCL) were assessed as an

indicator of the participants’ arousal.TheECGwas recorded fromthreeAg/AgCl electrodes,whichwere

attached via the modified lead-2 placement. The ECG-signal wassampled at 400 Hz and filtered with a high-pass filter of 0.5 Hz tostabilize baseline. None of the participants took beta-blockers orother hypertensive medication at the time of the experiment.

Skin conductance was monitored using silver electrodes tapedto the palmar surface of the left index and middle fingers. Thesignal was fed via a skin conductance processing unit (SCL 200,Biofeedback Systems, Manchester, UK). The filtered analogueoutput of the skin conductance level (SCL) was displayed online andrecorded digitally (sampling rate: 100 Hz) using SPIKE 2 software(CED, Cambridge, UK).

2.4. Additional questionnaire measures

2.4.1. Trait ruminationThe tendency towards ruminative thinking was assessed using

the Ruminative Response Scale (RRS) of the Response Style Ques-tionnaire (Nolen-Hoeksema & Morrow, 1991). The questionnaireconsists of 22 items assessing the frequency of ruminative thoughtsand action in response to depressive symptoms by asking partici-pants to indicate on a 4-point scale (1 ¼ ‘almost never’, 4 ¼ ‘almostalways’) what they generally do when they feel down, sad ordepressed (example item: “Think about how alone you feel”). The

A. Schaich et al. / J. Behav. Ther. & Exp. Psychiat. 44 (2013) 396e403 399

scale has been shown to possess good psychometric properties(Raes, Hermans, & Eelen, 2003).

2.4.2. Symptoms of depressionThe Beck Depression Inventory-II (BDI-II) (Beck, Steer, & Brown,

1996) was used to assess symptom level of depression. The BDI-IIis a standard measure of depressive symptoms with establishedpsychometric properties (van der Does, 2002).

2.4.3. Self-focusA visual analogue scale was used to assess the degree to which

participants’ thinking was focused on themselves, ranging from0 (not at all self-focused) to 100 (totally self-focused).

2.4.4. Film questionnaireParticipants filled in a short questionnaire about the film,

enquiring whether participants (1) had seen the film before (yes/no). In addition, they were asked to rate on a 1 (not at all) to 5(totally) scale, (2) towhat degree theywere able to identify with thevictim, (3) how distressing they found watching the film, (4) howwell they could concentrate on the film, and (5) how often theylooked away or closed their eyes during the film.

2.5. Procedure

After providing written informed consent, participantscompleted the demographics questionnaire, BDI, first PANAS andfirst self-focus rating. This was followed by a first 3 min resting HRand SCL assessment. Participants then received instructions for thescenario task, completed a practice scenariowith feedback from theresearcher, and then started to work through their assignedexperimental training condition. The scenario task was followed bythe second PANAS and the second self-focus rating. After that,participants completed the MEPS problem solving vignette(manipulation check). Participants filled in the third PANAS, whichwas followed by the second 3 min resting HR and SCL assessment.Next, participants watched the film scene. After that, participantsfilled in the fourth PANAS, followed by the third 3 min resting HRand SCL assessment and the first completion of the IntrusionsQuestionnaire. Next, participants were exposed to the reminders ofthe film scene. After that, participants filled in the fifth PANAS,followed by the fourth 3 min resting HR and SCL assessment andthe second Intrusions Questionnaire. At the end of the session,participants were explained the follow-up procedure. During thefollowing 7 days, participants received a daily e-mail with thePANAS and the Intrusions Questionnaire attached, instructing themto fill in the questionnaires and send them back to the experi-menter. After this follow-up period, participants received coursecredit and were called by the experimenter to check whether theystill experienced distress due to the film scene they had seen. Thestudy was approved by the local Research Ethics Committee.

3. Results

3.1. Baseline group differences

The two conditions did not differ in age and BDI Scores1 (seeTable 1). However, despite randomization, participants in the

1 BDI scores were also not significantly related to any of the intrusion scores. Inaddition, controlling for BDI scores in themain analyses did not change the pattern ofresults. However, note that the RRS � Condition interaction effect for the number ofintrusivememoriesduring thesessionwas reduced tonon-significance, t¼�1.78,p¼ .08, whereas the RRS � Condition interaction effect for the vividness of intrusivememories at follow-up was increased and now reached significance, t¼ 2.37, p¼ .02.

concrete processing conditions showed significantly higher traitrumination scores on the RRS than participants in the abstractprocessing condition. Therefore, RRS scores were controlled in allstatistical analyses.

3.2. Manipulation checks

3.2.1. Film questionnaireNone of the participants had seen the film prior to the study. On

average, participants indicated that they could concentrate well onthe film, were able to identify with the victim shown in the film,and felt highly distressed by the film. No significant differenceswere found between the conditions regarding the film-relatedvariables (see Table 1). However, participants in the abstract con-dition tended to report higher levels of concentration on the filmthan those in the concrete condition.2 As described earlier, twoparticipants indicated that they looked away or closed their eyes alot of the timewhile watching the film andwere therefore excludedfrom the analyses.

3.2.2. Appropriateness of film as analogue stressorTo investigate whether the film stressor had an effect on par-

ticipants’ mood, a 2 (time: pre-film versus post-film) � 2 (condi-tion: abstract versus concrete) mixedmodel ANOVAwas conductedwith the scores on the negative affect scale of the PANAS ques-tionnaire as the dependent variable. PANAS scores were skewedand therefore normalized via square root transformation prior toanalyses. A main effect of time emerged, showing that negativemood significantly increased from pre-film (see Table 1). TheTime � Condition interaction was not significant.

Similarly, separate 2 (time: pre-film baseline versus duringfilm) � 2 (condition) ANOVAs were conducted with the mean heartrate and mean skin conductance as dependent variables respec-tively (see Table 1). Again, significant main effects of time emergedin both analyses, showing that participants’ arousal significantlyincreased from the pre-film baseline to the film. In both analyses,no significant Time � Condition interaction effects emerged.

Participants reported on average 10.75 intrusions related to thefilm during the session (SD¼ 4.83) as well as 13.74 intrusions in theweek following the session (SD ¼ 13.63). In sum, the film wassuccessful as an analogue stressor in that it produced a substantialamount of intrusive memories and increased negative mood andarousal in our sample.

3.2.3. Induction of processing stylesIn order to test whether the induction of an abstract versus

concrete processing style was successful, participants’ responses tothe MEPS scenario following the induction period were coded by ablind rater regarding their level of concreteness. As expected, in theconcrete training condition, MEPS responses were coded assignificantly more concrete than in the abstract training condition(see Table 1).

In addition, the self-focus ratings completed before and after thetraining period were examined. As expected, there was no differ-ence regarding the impact of the training on participants’ self-focus.Finally, participants in the two conditions did not differ regardingtheir concentration on and clarity of the scenarios used in thetraining task. However, participants in the concrete condition ratedtheir thoughts as significantly more characterized by imagery thanthose in the abstract condition.

2 Controlling for the variable ‘Concentration on the Film’ did not change theresults of the main analyses.

Table 1Group differences on background and manipulation check variables.

Total (N ¼ 66) Abstract (n ¼ 32) Concrete (n ¼ 34) Statistics

Background variablesAge 20.05 (2.74) 20.13 (2.94) 19.97 (2.58) t(64) ¼ 0.23, p ¼ .82BDI 2.03 (2.33) 1.78 (2.26) 2.26 (2.70) t(64) ¼ �0.84, p ¼ .40RRS 43.39 (9.82) 40.31(7.87) 46.29 (10.66) t(64) ¼ �2.58, p ¼ .01

Film-related variablesConcentration on film 4.50 (0.77) 4.69 (0.47) 4.32 (0.95) t(64) ¼ 1.96, p ¼ .06Identification with victim 4.09 (0.87) 4.09 (0.96) 4.09 (0.79) t(64) ¼ 0.03, p ¼ .98Film-related distress 3.91 (1.00) 3.84 (1.11) 3.97 (0.90) t(64) ¼ �0.51, p ¼ .61PANAS-N pre-film 3.41 (0.28) 3.35 (0.13) 3.46 (0.37) T: F(1, 64) ¼ 122.64, p < .001

C: F(1, 64) ¼ 2.58, p ¼ .11T�C: F(1, 64) ¼ 0.88, p ¼ .35

PANAS-N post-film 4.53 (0.89) 4.38 (0.86) 4.68 (0.91)

Heart rate pre-film 67.33 (8.99) 68.06 (8.42) 66.64 (9.57) T: F(1, 62) ¼ 72.49, p < .001C: F(1, 62) ¼ 0.73, p ¼ .40T�C: F(1, 62) ¼ 0.27, p ¼ .60

Heart rate post-film 73.83 (9.09) 74.98 (8.44) 72.76 (9.67)

Skin conductance pre-film 16.74 (3.73) 16.88 (4.52) 16.60 (2.86) T: F(1, 64) ¼ 49.40, p < .001C: F(1, 64) ¼ 0.002, p ¼ .96T�C: F(1, 64) ¼ 1.18, p ¼ .28

Skin conductance post-film 18.21 (4.45) 18.12 (5.18) 18.30 (3.71)

Manipulation check concreteness trainingMEPS concreteness 3.28 (0.95) 3.03 (0.88) 3.52 (0.97) t(62) ¼ 2.08, p ¼ .04Self-focus pre-training 7.56 (1.44) 7.75 (1.65) 7.38 (1.21) T: F(1, 64) ¼ 2.71, p ¼ .11

C: F(1, 64) ¼ 0.70,p ¼ .41 T�C: F(1, 64) ¼ 0.25, p ¼ .62

Self-focus post-training 7.92 (1.61) 8.00 (1.69) 7.85 (1.56)

Concentration on scenarios 7.45 (1.57) 7.56 (1.72) 7.35 (1.43) t(64) ¼ 0.54, p ¼ .59Thought about unrelated topics 4.79 (2.19) 4.72 (2.28) 4.85 (2.13) t(64) ¼ �0.25, p ¼ .81Clarity of scenarios 7.59 (1.49) 7.66 (1.72) 7.53 (1.26) t(64) ¼ 0.34, p ¼ .73Verbal thinking versus imagery 6.33 (2.44) 4.78 (2.43) 7.79 (1.27) t(64) ¼ �6.36, p < .001

BDI ¼ Beck Depression Inventory; RSS ¼ Ruminative Response Scale; MEPS ¼ Mean Ends Problem Solving Inventory; T ¼ main effect time; C ¼ main effect condition;T�C ¼ interaction effect Time � Condition.

A. Schaich et al. / J. Behav. Ther. & Exp. Psychiat. 44 (2013) 396e403400

The induction of processing styles did not affect mood. Therewas neither a significant main effect of time, F(1, 64)¼ 0.00, p¼ .99,nor a significant Condition � Time interaction, F(1, 64) ¼ 0.98,p ¼ .33, from pre- to post-training.

In sum, results of the manipulation check showed that the in-duction of abstract versus concrete processing was successful.

3.3. Main analyses

3.3.1. Intrusive memories3.3.1.1. Intrusive memories during the session. In order to testwhether the concreteness training had an effect on the relationshipbetween trait rumination and intrusive memories experiencedduring the session, three different regression analysis were con-ducted with the number of intrusive memories, the vividness ofintrusive memories, and distress caused by intrusive memories asthe dependent variables respectively. Three predictor variableswere simultaneously entered in the analysis, namely trait rumi-nation (z-transformed scores of the RRS), condition (coded as adummy variable: 1 ¼ concrete, �1 ¼ abstract), and the interactionterm, i.e. the cross-product of Condition � Trait rumination.

In line with the hypotheses, a significant Condition � Traitrumination interaction was found when looking at the number ofintrusive memories during the session (see Table 2). Follow-upregression analyses split by condition showed that in the abstractcondition, there was a significantly positive association betweentrait rumination and the number of intrusive memories experi-enced, B ¼ 2.30, SE(B) ¼ 1.05, b ¼ 0.37, p ¼ .04. In the concretecondition, however, trait rumination and intrusive memories didnot show a significant association, B ¼ �0.35, SE(B) ¼ 0.76,b ¼ �0.08, p ¼ .65 (see also Fig. 1).

No significant Condition � Trait rumination interactionsemerged for the vividness and distress of intrusive memoriesduring the session (see Table 2).

3.3.1.2. Intrusive memories following the session. The same regres-sion analyses were repeated for the number of, vividness of, anddistress related to intrusive memories reported in the weekfollowing the session. Again, a significant Condition � Trait rumi-nation interaction were found for the number of intrusive mem-ories experienced, and trends for a similar effect emerged forintrusion vividness and distress (see Table 2). Follow-up regressionanalyses showed that in the abstract training condition traitrumination showed either significant positive associations or non-significant trends for positive associations with the number,B ¼ 6.18, SE(B) ¼ 3.16, b ¼ 0.34, p ¼ .06, vividness, B ¼ 6.37,SE(B) ¼ 2.92, b ¼ 0.37, p ¼ .04, and distress of intrusive memories,B ¼ 6.00, SE(B) ¼ 2.97, b ¼ 0.35, p ¼ .05, whereas no significantassociations were found in the concrete training condition, num-ber: B¼�1.60, SE(B)¼ 2.15, b¼�0.14, p¼ .46, vividness: B¼�1.35,SE(B) ¼ 2.59, b ¼ �0.10, p ¼ .61, distress: B ¼ �0.95, SE(B) ¼ 2.03,b ¼ �0.09, p ¼ .65.

3.3.2. Mood and arousalIn order to test whether the results extend to mood and arousal,

four additional regression analyses were conducted. For three an-alyses, residualized scores were computed first by regressing (a)the post-film PANAS score on the pre-film PANAS score, (b) HRduring film on HR during pre-film baseline, and (c) SCL during filmon SCL during pre-film baseline. In the following regression ana-lyses, these residualized scores were used as the dependent vari-ables. In the final regression analysis, negative mood in the weekfollowing the session (average PANAS-negative score for all 7 days)was the dependent variable.

As shown in Table 3, a significant Condition � Trait ruminationinteraction emerged when looking at residualized heart rateresponses to the film. In the abstract condition, there was apositive association between trait rumination and participants’heart rate responses to the film, B ¼ 1.93, SE(B) ¼ 1.36, b ¼ 0.26,p ¼ .17. In contrast, a significant negative association was found

Table 2Results of regression analyses predicting intrusive memories.

Dependent variable Predictor variables B SE(B) b t p R2

Intrusive memories during sessionNumber .09

RRS 0.97 0.65 0.20 1.50 .14Condition 0.39 0.65 0.08 0.63 .53RRS � condition �1.33 0.65 �0.26 �2.05 .045

Vividness .02RRS �2.97 4.33 �0.10 �0.69 .50Condition 1.72 4.09 0.06 0.42 .68RRS � condition �2.63 4.33 �0.08 �0.61 .55

Distress .02RRS �1.08 4.00 �0.04 �0.27 .79Condition 2.23 3.78 0.04 0.33 .75RRS � condition �3.78 4.00 �0.13 �0.95 .35

Intrusive memories during follow-upNumber .07

RRS 2.29 1.88 0.17 1.21 .23Condition -0.61 1.77 �0.05 �0.30 .73RRS � condition �3.89 1.88 �0.27 �2.07 .04

Vividness .07RRS 2.51 2.00 0.17 1.26 .21Condition -0.53 1.88 �0.04 �0.28 .78RRS � condition �3.86 2.00 �2.50 �1.93 .06

Distress .07RRS 2.53 1.78 0.19 1.42 .16Condition �0.93 1.67 �0.07 �0.55 .58RRS � condition �3.47 1.78 �0.25 �1.95 .06

PANAS ¼ Positive and Negative Affect Schedule; RRS ¼ Ruminative Response Scale.

A. Schaich et al. / J. Behav. Ther. & Exp. Psychiat. 44 (2013) 396e403 401

in the concrete condition, B ¼ �1.90, SE(B) ¼ 0.83, b ¼ �0.38,p ¼ .03.

A similar interaction effect emerged for residualized skinconductance scores; however, this was only significant at trendlevel (see Table 3). No significant Condition � Trait ruminationinteraction effects emerged for mood.

4. Discussion

The tendency to engage in ruminative thinking has beenidentified as a risk factor for the maintenance of PTSD. The current

Fig. 1. Slope of the relationship between trait rumination and intrusive memoriesduring the session as a function of training condition.

study tested whether the relationship between trait ruminationand analogue PTSD symptoms can be reduced by trainingparticipants to process information in a concrete style. As pre-dicted, following training in an abstract processing style, a sig-nificant association between trait rumination and the number ofintrusive memories experienced during the session as well as thenumber, vividness and distress of intrusive memories followingthe session was found. This replicates numerous earlier findingsshowing a strong association between rumination and PTSDfollowing real-life traumas as well as analogue stressors (e.g.,Ehring et al., 2008; Michael et al., 2007; Zetsche et al., 2009).However, in line with the hypotheses, this relationship dis-appeared in the concrete condition, in which participants weretrained in a concrete mode of processing before watching thestressful film. In the concrete condition, trait rumination wascompletely unrelated to any analogue PTSD symptoms.

The current study replicates earlier findings in the context ofdepressive rumination, where similar concreteness training wasfound to moderate the relationship between trait rumination andparticipants’ emotional response to failure (Moberly & Watkins,2006). In addition, the current findings are in line with Watkins’(2008) processing mode account of ruminative thinking, whichstates that rumination on negative content is only dysfunctional ifindividuals engage in an abstract style of ruminative thinking. Ourstudy adds to an emerging evidence base showing that this theoryalso applies to trauma-related rumination (Ehring et al., 2008;Ehring, Szeimies et al., 2009; Santa Maria et al., 2012).

How can the differential effect of abstract versus concretethinking on intrusivememories be explained on a theoretical level?According to Ehlers and Clark’s (2000) cognitive model of PTSD,two conditions are required to recover from traumatic events. First,the traumamemory needs to be elaborated and contextualized, andsecond, negative appraisals of the trauma and/or its consequencesneed to bemodified. An abstract style of processing can be expectedto interfere with both processes, whereas concrete thinking mayfacilitate both aims. Specifically, for the elaboration and contextu-alization of the trauma memory exposure to specific details of the

Table 3Results of regression analyses predicting mood and arousal.

Dependent variable Predictor variables B SE(B) b t p R2

Mood and arousal in response to the filmPANAS-negative .05

RRS 1.61 1.08 0.21 1.49 .14Condition 0.30 1.02 0.04 0.30 .77RRS � condition �0.98 1.08 �0.12 �0.90 .37

Heart rate .11RRS 0.17 0.78 0.03 0.02 .98Condition �0.62 0.74 �0.11 �0.85 .40RRS � condition �1.91 0.78 �0.32 �2.47 .02

Skinconductance

.07RRS 0.04 0.22 0.03 0.19 .85Condition 0.23 0.21 0.14 1.06 .29RRS � condition �0.40 0.22 �0.23 �1.78 .08

Mood during follow-upPANAS-negative .06

RRS 0.05 0.06 0.11 0.82 .42Condition 0.02 0.05 0.05 0.39 .70RRS � condition 0.07 0.06 0.17 1.28 .21

PANAS ¼ Positive and Negative Affect Schedule; RRS ¼ Ruminative Response Scale.Note. For regression analyses testing response to the film, residualized scores were used.

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traumatic experience is necessary, which is more likely to happenduring concrete than abstract thinking. Similarly, abstract thinkingcan be expected to reinforce global trauma-related appraisals; onthe other hand, concrete thinking should lead to individuals takingin specific disconfirming evidence that is needed to modify theseappraisals (see also Ehring, Kleim, & Ehlers, 2011, for a moreextensive discussion).

Intrusive memories are usually considered as the hallmarksymptom of PTSD. Therefore, our analyses mainly focused on theseoutcome variables. However, in exploratory analyses, we addi-tionally checked whether the results extend to variables typicallyassociated with PTSD, such as negative mood and arousal inresponse to the stressor. Results showed that the processing modetraining did not impact on the relationship between trait rumina-tion and participants’ mood in response to the film or during theweek following the session. Interestingly, however, the processingmode induction did moderate the relationship between traitrumination and participants’ heart rate ande at a trend levele skinconductance in response to the film. Following abstract training,trait rumination was related to greater increase in arousal duringthe film, whereas the oppositewas true following concrete training.This pattern parallels the findings for intrusive memories as thedependent variable.

It is noteworthy that no main effect of training in an abstractversus concretemode of processing on intrusivememories ormoodwas found. Earlier research has shown inconsistent results in thisregard. Whereas some studies did find a main effect of processingmodes (e.g., Watkins et al., 2008), other earlier findings parallel ourresults in that only a significant Trait rumination � Conditioninteraction but no significant main effect of condition was found(Moberly & Watkins, 2006; Watkins, 2004). Future research isneeded to investigate the boundary conditions of main and inter-action effects found in this area.

The findings of the current study need to be interpreted in thelight of its limitations. First, the current study lacked a no-trainingcontrol condition, in which no particular mode or style of pro-cessing was induced. Therefore, it remains unclear whether thecurrent results are mainly due to the dysfunctional effects of theabstract training condition, the functional effects of the concretetraining condition, or both. Future studies should include a neutralno-training control condition to clarify the direction of the effectand give insight into the default response of untrained individuals.Second, although the trauma film paradigm is generally regarded as

a valid paradigm to study the development and modulation ofintrusive memories (Holmes, Brewin, & Hennessy, 2004;Weidmann et al., 2009), it also has limitations. Most importantly, itclearly differs from real-life traumatic events in stressor severity. Inaddition, it can be expected that processing a film is characterizedby much lower levels of self-reference and self-relevance thanprocessing personally experienced events. Therefore, the results ofthe current study need to be replicated in survivors of real-lifetraumas before any firm conclusions for this population can bedrawn. Third, a relatively large number of regression analyses onintrusion scores were conducted without controlling for multipletesting. Due to the relatively small sample size, it did not appearappropriate to adjust a-levels as this may have resulted in type IIerrors. However, given the use of multiple testing without a-adjustment the results of the current study have to be regarded aspreliminary. The findings need to be replicated in future researchbefore any strong conclusions can be drawn. Fourth, the distinctionbetween abstract versus concrete processing comprises differentdimensions (e.g., abstract versus concrete thinking; evaluativeversus non-evaluative thinking). In addition, the manipulation mayhave also resulted in differences in the extent of imagery versusverbal processing used. As these dimensions were manipulatedsimultaneously in the current study, we are unable to establish therelative important of the different dimensions based on the currentdata. Future research is needed to investigate this issue moreclosely by manipulating the different dimensions independently.Finally, although the RRS is a well-validated and widely usedmeasure of trait rumination, one may argue that its focus ondepressive rumination may be too narrow for the purpose of thecurrent study. Future studies should consider using content-independent measures of trait rumination, such as the Persevera-tive Thinking Questionnaire (Ehring, Zetsche et al., 2011) or theRepetitive Thinking Questionnaire (McEvoy, Mahoney, & Moulds,2010) instead.

In sum, the current study provides preliminary support for theprocessing mode hypothesis of trauma-related rumination. Inaddition to replicating earlier findings that an abstract style ofthinking is at least partially responsible for the dysfunctional effectsof trauma-related rumination, the current study extends earlierresearch by showing that the relationship between rumination andPTSD symptoms can be modified.

Due to the study limitations, especially the use of multipletesting without a-adjustment, the current results are preliminary

A. Schaich et al. / J. Behav. Ther. & Exp. Psychiat. 44 (2013) 396e403 403

and need to be interpreted with caution. However, if replicated infuture research, this finding may have clinical implications. Forexample, concreteness training has been developed as a guidedself-help treatment for rumination and depression, and has beenshown to be efficacious in a proof-of-principle study (Watkins,Baeyens, & Read, 2009) and a Phase II randomized controlled trialin patients with major depression recruited in primary care(Watkins et al., 2012). Thus, if the causal impact of concreteness onprotecting from PTSD symptoms is confirmed in a trauma-exposedpopulation, such concreteness training could potentially be usedwith individuals at risk for trauma exposure and/or PTSD (for amore extensive discussion, see Topper, Emmelkamp, & Ehring,2010). In addition, there is preliminary evidence suggesting thatexcessive levels of rumination may impair the effects of evidence-based PTSD treatment protocols (Echiverri, Jaeger, Chen, Moore, &Zoellner, 2011). Future research is therefore needed to testwhether the addition of concreteness training to standard PTSDtreatment may help to overcome rumination as a roadblock forrecovery from trauma.

Conflict of interest

The authors declare that they have not conflict of interest.

Acknowledgements

We are grateful to Bert Molenkamp for technical support and toLeonie Hutten for her help with data collection.

References

Ball, S. C., & Brewin, C. R. (2012). The effect of rumination on intrusive images andmood: an experimental investigation using the trauma film paradigm. Journal ofExperimental Psychopathology, 3, 297e309.

Beck, A. T., Steer, R. A., & Brown, G. K. (1996). The Beck Depression Inventory (2nded.). San Antonio, TX: The Psychological Corporation.

Calhoun, L. G., Cann, A., Tedeschi, R. G., & McMillan, J. (2000). A correlational test ofthe relationship between posttraumatic growth, religion, and cognitive pro-cessing. Journal of Traumatic Stress, 13, 521e527.

van der Does, A. J.W. (2002).Handleiding bij de Nederlandse versie van Beck DepressionInventory e second edition (BDI-II-NL) [Manual of the Dutch version of the BeckDepression Inventory e second edition (BDI-II-NL)]. Amsterdam, NL: Harcourt.

Echiverri, A. M., Jaeger, J. J., Chen, J. A., Moore, S. A., & Zoellner, L. A. (2011).“Dwelling in the past”: the role of rumination in the treatment of posttraumaticstress disorder. Cognitive and Behavioral Practice, 18, 338e349.

Ehlers, A., & Clark, D. M. (2000). A cognitive model of posttraumatic stress disorder.Behaviour Research and Therapy, 38, 319e345.

Ehring, T., Frank, S., & Ehlers, A. (2008). The role of rumination and reducedconcreteness in the maintenance of posttraumatic stress disorder and depres-sion following trauma. Cognitive Therapy and Research, 32, 488e506.

Ehring, T., Fuchs, N., & Kläsener, I. (2009). The effects of experimentally inducedrumination versus distraction on analogue posttraumatic stress symptoms.Behavior Therapy, 40, 403e413.

Ehring, T., Kleim, B., & Ehlers, A. (2011). Combining clinical studies and analogueexperiments to investigate cognitive mechanisms in posttraumatic stressdisorder. International Journal of Cognitive Psychotherapy, 4, 165e177.

Ehring, T., Szeimies, A.-K., & Schaffrick, C. (2009). An experimental analogue studyinto the role of abstract thinking in trauma-related rumination. BehaviourResearch and Therapy, 47, 285e293.

Ehring, T., Zetsche, U., Weidacker, K., Wahl, K., Schönfeld, S., & Ehlers, A. (2011). ThePerseverative Thinking Questionnaire (PTQ): validation of a content-independent measure of repetitive negative thinking. Journal of BehaviorTherapy and Experimental Psychiatry, 42, 225e232.

Holmes, E. A., & Bourne, C. (2008). Inducing and modulating intrusive emotionalmemories: a reviewof the traumafilmparadigm.Acta Psychologica,127, 553e566.

Holmes, E. A., Brewin, C. R., & Hennessy, R. G. (2004). Trauma films, informationprocessing, and intrusive memory development. Journal of ExperimentalPsychology: General, 133, 3e22.

Kleim, B., Ehlers, A., & Glucksman, E. (2007). Early predictors of chronic post-traumatic stress disorder in assault survivors. Psychological Medicine, 37,1457e1468.

McEvoy, P. M., Mahoney, A. E. J., & Moulds, M. L. (2010). Are worry, rumination, andpost-event processing one and the same?: development of the repetitivethinking questionnaire. Journal of Anxiety Disorders, 24, 509e519.

Michael, T., Halligan, S. L., Clark, D. M., & Ehlers, A. (2007). Rumination inposttraumatic stress disorder. Depression and Anxiety, 24, 307e317.

Moberly, N. J., & Watkins, E. R. (2006). Processing mode influences the relationshipbetween trait rumination and emotional vulnerability. Behavior Therapy, 37,281e291.

Moore, S. A., Zoellner, L. A., & Mollenholt, N. (2008). Are expressive suppression andcognitive reappraisal associated with stress-related symptoms? BehaviourResearch and Therapy, 46, 993e1000.

Nolen-Hoeksema, S., & Morrow, J. (1991). A prospective study of depression andposttraumatic stress symptoms after a natural disaster: the 1989 Loma Prietaearthquake. Journal of Personality and Social Psychology, 61, 115e121.

Platt, J. J., & Spivack, G. (1972). Problem-solving thinking of psychiatric patients.Journal of Consulting and Clinical Psychology, 39, 148e151.

Raes, F., Hermans, D., & Eelen, P. (2003). De Nederlandstalige versie van deRuminative Response Scale (RRS-NL) en de Rumination on Sadness Scale(RSS-NL) [The Dutch version of the Ruminative Response Scale (RRS-NL) andthe Rumination on Sadness Scale (RRS-NL)]. Gedragstherapie, 36, 97e104.

Santa Maria, A., Reichert, F., Hummel, S. B., & Ehring, T. (2012). Effects of ruminationon intrusive memories: does processing mode matter? Journal of BehaviorTherapy and Experimental Psychiatry, 43, 901e909.

Stöber, J., & Borkovec, T. D. (2002). Reduced concreteness of worry in generalizedanxiety disorder: findings from a therapy study. Cognitive Therapy and Research,26, 89e96.

Topper, M., Emmelkamp, P. M. G., & Ehring, T. (2010). Improving prevention ofdepression and anxiety disorders: repetitive negative thinking as a promisingtarget. Applied and Preventive Psychology, 14, 57e71.

van Emmerik, A. A. P., Kamphuis, J. H., & Emmelkamp, P. M. G. (2008). Treating acutestress disorder and posttraumatic stress disorder with cognitive behavioraltherapy or structured writing therapy: a randomized controlled trial.Psychotherapy and Psychosomatics, 77, 93e100.

Verwoerd, J., De Jong, P. J., & Wessel, I. (2008). Low attentional control and thedevelopment of intrusive memories following a laboratory stressor. Journal ofPsychopathology and Behavioral Assessment, 30, 291e297.

Verwoerd, J., Wessel, I., de Jong, P. J., & Nieuwenhuis, M. M. W. (2009). Preferentialprocessing of visual trauma-film reminders predicts subsequent intrusivememories. Cognition & Emotion, 23, 1537e1551.

Watkins, E. (2004). Adaptive and maladaptive ruminative self-focus duringemotional processing. Behaviour Research and Therapy, 42, 1037e1052.

Watkins, E. R. (2008). Constructive and unconstructive repetitive thought.Psychological Bulletin, 134, 163e206.

Watkins, E. R., Baeyens, C. B., & Read, R. (2009). Concreteness training reducesdysphoria: proof-of-principle for repeated cognitive bias modification indepression. Journal of Abnormal Psychology, 118, 55e64.

Watkins, E., Moberly, N. J., & Moulds, M. L. (2008). Processing mode causallyinfluences emotional reactivity: distinct effects of abstract versus concreteconstrual on emotional response. Emotion, 8, 364e378.

Watkins, E., & Moulds, M. L. (2007). Reduced concreteness of rumination indepression: a pilot study. Personality and Individual Differences, 43, 1386e1395.

Watkins, E. R., Taylor, R. S., Byng, R., Baeyens, C., Read, R., Pearson, K., et al. (2012).Guided self-help concreteness training as an intervention for major depressionin primary care: a phase II randomized controlled trial. Psychological Medicine,42, 1359e1371.

Watson, D., Clark, L. A., & Carey, G. (1988). Positive and negative affectivity andtheir relation to anxiety and depressive disorders. Journal of AbnormalPsychology, 97, 353.

Weidmann, A., Conradi, A., Gröger, K., Fehm, L., & Fydrich, T. (2009). Using stressfulfilms to analyze risk factors for PTSD in analogue experimental studies e whichfilm works best? Anxiety, Stress and Coping, 22, 549e569.

Wells, A., & Papageorgiou, C. (1995). Worry and the incubation of intrusive imagesfollowing stress. Behaviour Research and Therapy, 33, 579e583.

Wells, A., & Sembi, S. (2004). Metacognitive therapy for PTSD: a core treatmentmanual. Cognitive and Behavioral Practice, 11, 365e377.

Zetsche, U., Ehring, T., & Ehlers, A. (2009). The effects of rumination on mood andintrusive memories after exposure to traumatic material: an experimentalstudy. Journal of Behavior Therapy and Experimental Psychiatry, 40, 499e514.