derealization during acute social stress in social phobia

Journal of Anxiety Disorders 27 (2013) 178–187

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Journal of Anxiety Disorders

Depersonalization/derealization during acute social stress in social phobia Juergen Hoyer a,∗ , David Braeuer a , Stephen Crawcour a , Elisabeth Klumbies b , Clemens Kirschbaum b a b

Institute of Clinical Psychology and Psychotherapy, Technische Universitaet Dresden, Germany Institute of Biopsychology, Technische Universitaet Dresden, Germany

a r t i c l e

i n f o

Article history: Received 8 June 2012 Received in revised form 13 December 2012 Accepted 20 January 2013 Keywords: Depersonalization Derealization Social anxiety disorder Social phobia Post-event processing Trier Social Stress Test (TSST)

a b s t r a c t The present study aimed at investigating how frequently and intensely depersonalization/derealization symptoms occur during a stressful performance situation in social phobia patients vs. healthy controls, as well as testing hypotheses about the psychological predictors and consequences of such symptoms. N = 54 patients with social phobia and N = 34 control participants without mental disorders were examined prior to, during, and after a standardized social performance situation (Trier Social Stress Test, TSST). An adapted version of the Cambridge Depersonalization Scale was applied along with measures of social anxiety, depression, personality, participants’ subjective appraisal, safety behaviours, and post-event processing. Depersonalization symptoms were more frequent in social phobia patients (92%) than in controls (52%). Specifically in patients, they were highly positively correlated with safety behaviours and post-eventprocessing, even after controlling for social anxiety. The role of depersonalization/derealization in the maintenance of social anxiety should be more thoroughly recognized and explored. © 2013 Elsevier Ltd. All rights reserved.

1. Introduction Social phobia (SP, also defined as social anxiety disorder, SAD) is characterized by persistent fears of one or more social situations in which the person is exposed to others and expects to be scrutinized. Those affected fear acting in an embarrassing way (American Psychiatric Association, 2000). According to the DSM-IV-TR criteria, such fears are recognized as unreasonable and excessive. Nevertheless, exposure to such feared situations may invariably trigger anxiety, with levels possibly escalating to panic attacks. SP is related to clinically significant distress, as well as impairment in social, occupational, or other important areas of functioning (American Psychiatric Association, 2000). Comorbid psychopathology (other anxiety disorders, mood disorders, substance abuse) is common (e.g., Fehm, Beesdo, Jacobi, & Fiedler, 2008). Current psychological models of social phobia emphasize the role of cognitive factors for the development and maintenance of the disorder (Clark & Wells, 1995; Hofmann, 2007; Clark, 2001; Rapee & Heimberg, 1997), which include high social

∗ Corresponding author at: Technische Universität Dresden, Klinische Psychologie und Psychotherapie, Hohe Str. 53, D-01187 Dresden, Germany. Tel.: +49 351 46336986; fax: +49 351 46336955. E-mail address: [email protected] (J. Hoyer). 0887-6185/$ – see front matter © 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.janxdis.2013.01.002

standards, social apprehension, heightened self-focused attention, negative self-perception, high estimated social costs, low perceived emotional control, perceived poor social skills, anticipation of social mishaps, avoidance and safety behaviours, and post-event rumination. To the best of our knowledge however, symptoms of depersonalization or derealization have not been explicitly integrated in any of these models although clinical data suggest that these symptoms are associated with social anxiety (e.g., Michal et al., 2005; Simeon, Knutelska, Nelson, & Guralnik, 2003). Depersonalization and derealization are defined as subjective experiences of unreality in one’s sense of self (depersonalization, DP) and the outside world (derealization, DR) (Simeon, 2004). These symptoms, which have been known already in the early psychopathology literature (Schilder, 1914) by the term autoscopia, occur in a continuum ranging from transient episodes in healthy individuals under specific conditions to mental and emotional disorders including depersonalization disorder (DPD; Hunter, Phillips, Chalder, Sierra, & David, 2003). A maximal expression of DP/DR as observed in DPD may include symptoms such as e.g., emotional numbing, lack of empathy, a sense of isolation, a dream-like state, impaired concentration, “mind numbness” or “racing thoughts,” memory impairments, difficulties in processing new information, dizziness and sensory distortions, or an altered perception of time (American Psychiatric Association, 2000).

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Transient DP/DR symptoms are also typical for many anxiety disorders, especially for post-traumatic stress disorder (PTSD). DP/DR in PTSD may occur either during the trauma (i.e., peritraumatically) or in the immediate aftermath of the trauma (for an overview see Bryant, 2007). Peritraumatic DP/DR have been suggested to minimize adverse emotional reactions to occurring traumatic events by restricting awareness of their experience (e.g., Putnam, 1989) with the result of impairing access to critical memories and thus to emotional processing of the trauma (Marmar et al., 1994). Furthermore, DP and DR represent common symptoms occurring during panic attacks (e.g., Ball, Robinson, Shekhar, & Walsh, 1997; Cassano et al., 1989; Márquez, Segui, Garcia, Canet, & Ortiz, 2001; Segui et al., 2000; Toni et al., 1996). Importantly, Márquez et al. (2001) and others (Cassano et al., 1989; Toni et al., 1996) found that patients with panic disorder presenting DP displayed a lower level of functioning, a greater clinical severity (i.e., higher number of panic attacks, higher state anxiety, anticipatory anxiety, agoraphobia, comorbidity with specific phobia), in addition to a greater phobic avoidance relative to panic disorder with no DP. As panic attacks can occur in every anxiety disorder (e.g., Rapee, Sanderson, McCauley, & DiNardo, 1992) many anxiety patients may experience sensations of “unreality.” In phobias, however, these states may only occur during active confrontation with the feared stimulus. Symptom reporting of these patients may mainly refer to avoidance and associated negative consequences, as opposed to the symptoms occurring during the actively avoided situations. The latter problem may be relevant in social phobia, as patients suffering from this disorder may particularly shy away from reporting “unusual” states of mind. Little research has been performed examining the occurrence of DR and/or DP in social phobia. Nevertheless there is some evidence that their role in the disorder should not be neglected (e.g., Michal et al., 2005, 2006; Simeon et al., 2003). Although Clark and Wells (1995) do not mention DP or DR in their model when referring to the anxiety induced deficits in SP, data from their group demonstrated that social phobia patients, other than controls, tend to take on an “observer perspective” (Wells, Clark, & Ahmad, 1998) and experience a heightened self-focused attention (Spurr & Stopa, 2003) in social situations. In this study, however, it was not examined whether such phenomena occurred deliberately or were rather experienced as subjectively uncontrollable symptoms. Furthermore, particularly when undergoing test and other social performance situations, those suffering from social phobia have been described as presenting symptoms including self-perceptions from an observer perspective, the feeling of one’s mind going blank and sensory distortions (Fehm & Fydrich, 2011; Michal et al., 2005). These symptoms can be well identified as symptoms of DP/DR. Their more elaborate description in social phobia and their integration in models of the disorder may enhance its understanding and shed light on the processes underlying its maintenance. Studies on DP/DR in SP have mostly employed scales and questionnaires, querying psychotherapy patients about their DP/DR symptoms (e.g., Michal et al., 2005). As expected, those patients with pathological DP/DR symptoms received an SP diagnosis more frequently than those presenting no such symptoms (Michal et al., 2006). Further, moderately strong correlations (i.e., between 0.53 and 0.62) were found between social anxiety and DP/DR symptoms in both psychotherapy patients and healthy controls (Michal et al., 2005). Other researchers (Simeon et al., 2003) also detected fulfilment of the criteria for comorbid SP in 47% of patients with DPD, as well as in 30% of patients with avoidant personality disorder. SP, along with depression and panic disorder was also found to be a predictor for comorbid DPD with an odds ratio of 3.7 in the general population (Michal et al., 2009).

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The scarcity of research on DP/DR in SP might be explained by the methodological challenges regarding their accurate detection. Studies like those cited above rely on questionnaire methodology and make a number of biases probable, including, e.g., the memory or recall bias, as found in other clinical populations (e.g., Mathews & Bradley, 1983). Based on his/her present affective status, the individual will either over- or underreport relevant symptoms, which might have occurred in the past. Moreover, other authors criticize that retrospective reporting of symptoms is strongly influenced by implicit references to one’s self-concept, an effect known as consistency bias (Leising, 2011; Sadler & Woody, 2003). In contrast, observational studies, which would directly measure DP/DR symptoms exactly during their occurrence, cannot be meaningfully conducted, as directly asking people whether they are experiencing these symptoms would change both the situation and the natural occurrence of DP/DR. Conversely, ways of detecting DP/DR other than interview or self-report methodology, would not be appropriate, as DP/DR are only observable by introspection and objective measures for DP/DR have yet to be defined. Due to these problems it is not surprising that, to the best of our knowledge, no studies have investigated DP/DR in situ in social phobia. Accordingly, central questions about the role of DP/DR in SP remain unanswered. It remains unknown, how frequent DP/DR occur in social stress situations in SP and how these symptoms are perceived. Also, there is little information on possible predictors and consequences of DP/DR (e.g., how they are interrelated to other psychological variables such as anxiety and depression). An especially important question is whether DP/DR might contribute to further avoidance of social situations, thus contributing to the maintenance of the disorder. Given that DP/DR are known to be experienced as highly aversive (e.g., Ackner, 1954; Hunter et al., 2003), we find it plausible that efforts to reduce anxiety levels eliciting or co-occurring with DP/DR might already be initiated during the situation. Simply put, individuals who are experiencing DP/DR might strongly tend to exhibit safety behaviours (Clark & Wells, 1995) during the situation. As DP/DR are typically not part of the everyday experience, individuals might conceive them as evidence for a dysfunction. They might tend to ruminate longer and more intensely over the situation than other individuals, a process which has been termed post-event processing (Clark & Wells, 1995) or post-event rumination (Abbott & Rapee, 2004). As it is presently not clear whether post-event processing after social situations is specific for SP (Fehm, Schneider, & Hoyer, 2007) or not (McEvoy & Kingsep, 2006), we expect post-event processing to be higher after having experienced DP/DR in a social situation (as opposed to not) in all participants of our study. In the present study we intended to solve at least some of the above mentioned methodological problems and to answer the questions raised. Our basic starting point was the idea of using a standardized paradigm known to reliably elicit strong reactions of social stress, and having the participants report on DP/DR directly after this situation. The Trier Social Stress Test (TSST; Kirschbaum, Pirke, & Hellhammer, 1993) offers excellent opportunities to examine whether social performance elicits not only typical symptoms of stress but also those of DP/DR. It is a standardized experimental procedure through which a moderate level of psychological stress can be induced in a laboratory setting. The protocol comprises an anticipation and a test period during which participants are required to stand in front of an audience and deliver a free speech or perform a mental arithmetic task (Kirschbaum et al., 1993). To examine patients with SP while applying the TSST has the advantage that the test situation is standardized and can be objectively described. Thus, no situational variance would explain differences in psychological outcomes. Moreover, we planned to ask the respondents directly after having undergone the TSST about

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their experiences, specifically their DP/DR, to minimize retrospective and, in part, also consistency bias. Based on these methodological considerations we were able to give a more detailed empirical description of DP/DR during social performance and to test the following hypotheses: Hypothesis 1. We expected SP patients to show a greater number of DP/DR symptoms relative to healthy controls (HC). Hypothesis 2. DP/DR would be positively associated with safety behaviours during the situation. Hypothesis 3. DP/DR would be predictive of subsequent postevent processing. 2. Materials and methods 2.1. Participants N = 55 (24 females; age = 26.5, SD = 6.0) patients with SP and N = 34 (16 females; age = 25.3, SD = 6.4) matched healthy controls participated in this study. The patients were recruited in the outpatient clinic of the Institute of Clinical Psychology and Psychotherapy of the Technische Universitaet Dresden (Germany). We conducted the Munich-Composite International Diagnostic Interview (DIAX/M-CIDI; Wittchen & Pfister, 1997), a fully standardized diagnostic instrument to confirm DSM-IV diagnoses for SP and comorbid mental disorders. Patients were included if they met the DSM-IV criteria for SP as primary diagnosis and did not have any comorbid substance related disorder, psychotic disorder, personality disorder (except for avoidant, dependant or obsessive-compulsive disorder) or organic mental disorder. Furthermore, to ensure comparability to another trial (Leichsenring et al., 2009), SP patients had to exhibit a score in the Liebowitz Social Anxiety Scale (LSAS; Liebowitz, 1987; German version: Stangier & Heidenreich, 2005) above 30 to be included. At the time of the study, none of the patients was in (any other) psychotherapeutic treatment. Of all participants who were eligible for the study (N = 64), 9.4% (n = 6) withdrew from participation. Of the remaining 58 patients, 4.7% (n = 3) withdraw informed consent due to fear of the stress test and injections. HC subjects were recruited via advertisement. They were included if the stem questions of the DIA-X/M-CIDI indicated no lifetime psychiatric disorder (Wittchen & Perkonigg, 1997) and when they fulfilled the matching criteria of age and gender. Smoking and hormonal contraception status were also assessed, as they represent confounds when attempting to determine HPA hypo- vs. hyperactivity in relation to social stress. Simply put, whereas the ingestion of contraceptives may reduce the amount of bioavailable (i.e., “free”) cortisol (Kirschbaum, Kudielka, Gaab, Schommer, & Hellhammer, 1999), nicotine may chronically elevate ACTH and/or cortisol with reduced axis responsiveness (Kirschbaum, Wüst, & Strasburger, 1992). Exclusion criteria for all subjects were: any physical condition or intake of medication that influences the HPA axis, smoking more than 10 cigarettes per day and pregnancy or breastfeeding. All women were tested in the luteal phase of their menstrual cycle. Written informed consent was obtained from all subjects and the study protocol was approved by the local ethics committee (EK 137062007). 2.2. Procedure All participants underwent the TSST (Kirschbaum et al., 1993), a standardized public speaking task involving a mock job interview and mental arithmetic. Furthermore, we assessed safety behaviours, subjective appraisal and anxiety during the situation via questionnaires. During the anticipation of the TSST, participants

had to fill in the Primary Secondary Appraisal Scale (PASA; Gaab, Rohleder, Nater, & Ehlert, 2005) to assess anticipatory cognitive appraisal. Furthermore, immediately after the TSST subjects rated the stressfulness of the previous situation on visual analogue scales ranging from 0 to 100 (VAS; Gaab et al., 2005) and filled out a safety behaviour questionnaire (adapted from Clark et al., 1995). The intensity and frequency of PEP was measured one week later with the PEP Questionnaire (PEP-Q; Fehm et al., 2007). 2.3. Measures 2.3.1. Depersonalization experiences during the TSST In the present study an adapted German version of the Cambridge Depersonalization Scale (CDS; Sierra & Berrios, 2000; German version: Michal et al., 2004) was used to assess symptoms of DP/DR. The CDS contains 29 items that address complaints traditionally related to the depersonalization disorder, including, e.g., abnormal experiences affecting different sensory modalities; inability to experience a range of different emotions; heightened self-observation and lack of body ownership feelings, somatosensory distortions, out-of-body experiences, autoscopia, in addition to a lack of agency feelings. The German version of the CDS presents internal consistency and reliability comparable to the English original version (Cronbach ˛ = 0.95, Guttman Split-half = 0.95). Its use was preferred over the German version of the Dissociative Experiences Scale (DES; Bernstein & Putnam, 1986), due to its more accurate and valid measurement of the phenomenal complexity of DP/DR (Michal et al., 2004). Furthermore, the CDS contained a larger number of items that were applicable to our experimental setting relative to the DES. While the CDS is typically applied as a trait measure, the instruction of the scale was modified to evaluate DP/DR during the occurring test situation (instead of the past six months) and selected items that were applicable (e.g., Item 1: “Out of the blue, I feel strange, as if I were not real or as if I were cut off from the world.”). Items not relevant to the test situation (e.g., Item 5: “My favourite activities are no longer enjoyable.”) were excluded. The remaining 15 CDS items were scored from 0 (none, never, not at all) to 100 (very strong, always) on a visual analogue scale. For the original German trait version of the CDS (Michal et al., 2004) moderate to good reliability and validity coefficients have been reported. In a pre-test of the adapted version, including 23 respondents of the TSST (taking part in other studies), an internal consistency of ˛ = .87 was established. In the present investigation, the internal consistency of the scale was ˛ = .87 in the healthy sample and ˛ = .88 in the patient sample. As a side note, it should be mentioned that, because only the abbreviated CDS scale was employed, it was not possible to compare the mean scores of the state CDS with that reported by Hunter, Baker, Phillips, Sierra, and David (2005) for a sample of patients with depersonalization disorder. 2.3.2. Symptoms of social anxiety (expert rating) To assess SP, the Liebowitz Social Anxiety Scale (LSAS; Liebowitz, 1987; German version: Stangier & Heidenreich, 2005) as a clinician-administered questionnaire was used. It assesses fear and avoidance in 24 social interaction and performance situations during the last week. Each item is rated on two 4-point Likert scales of fear and avoidance. In the present study the total score was computed. Additionally, also the Brief Social Phobia Scale (BSPS; Davidson, Miner, & De Veaugh-Geiss, 1997; German; Chaker, Haustein, Hoyer, & Davidson, 2011), a well-validated short rating form of social phobia, was applied. Other than the LSAS, this 10-item scale also integrates bodily symptoms such as blushing, trembling and sweating.

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2.3.3. Symptoms of social anxiety (self-rating) Furthermore, the following well-validated self-rating scales for measuring social phobia were used: the Social Phobia Anxiety Inventory (SPAI; Turner, Beidel, Dancu, & Stanley, 1989; German version: Fydrich, 2003), the Brief Fear of Negative Evaluation Scale (BFNE; Watson & Friend, 1969; German version: Vormbrock & Neuser, 1983) and the Social Interaction/Social Performance Scales (SIAS/SPS; Mattick & Clarke, 1989; Stangier, Heidenreich, Berardi, Golbs, & Hoyer, 1999). 2.3.4. Personality The German version of Cloningers Tridimensional Personality Questionnaire (TPQ; Cloninger, Przybeck, & Svrakic, 1991; German version: Weyers, Krebs, & Janke, 1995) contains 100 dichotomous (yes/no) self-report questions which cover the three personality scales Novelty Seeking (NS, 34 items), Harm Avoidance (HA, 34 items), and Reward Dependence (RD, 30 items). 2.3.5. Subjective symptoms during the stress test We assessed anticipatory cognitive appraisal processes after the 3 min preparation time during the TSST with the Primary Appraisal Secondary Appraisal Scale (PASA; Gaab et al., 2005). Its 16 items contain the dimensions “threat” plus “challenge” (representing primary appraisal), and “control expectancy” plus “self-concept of own abilities” (representing Secondary Appraisal). 2.3.6. Depression To assess depression, the Beck Depression Inventory (BDI; Beck, Ward, Mendelson, Mock, & Erbaugh, 1961; German version: Hautzinger, Bailer, Worall, & Keller, 1995) was used. The BDI is a widely used self-report questionnaire consisting of 21 items which can be computed into a total score.

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scored from 0 (none, never, not at all) to 100 (very strong, always) on a visual analogue scale. Furthermore, for the purpose of this study, the participants were instructed to refer to the TSST situation when answering the items. In the present investigation, the internal consistency of the scale was ˛ = .8 in the healthy sample and ˛ = .9 in the patient sample. 2.3.8. Physiological measures For the assessment of cortisol levels during the TSST eight saliva and blood samples were drawn and heart rate and heart rate variability were continuously recorded using a mobile device. However, physiological data are not the focus of this article and will be published elsewhere. 2.3.9. Statistical analyses To test the hypothesized difference between the SP group and the HC group in terms of DP/DR symptoms an independent-sample t-test was applied. Please note that we also used independentsample t-tests for exploring statistical differences between groups in other clinical variables such as LSAS, SPAI, BFNE, BSPS, SIAS, SPS, BDI, CDS, CDSlog (logarithmized CDS-value, applied to compensate for strong deviations from the normal distribution), SBQ-G, PEP-Q and the subscales of the TPQ, Novelty Seeking, Harm Avoidance, Reward Dependence and the subscales of the PASA. To test for predictors of CDS and PEP-Q, bivariate correlational analyses were performed first to ascertain the relationship between the severity of the criteria and the variables. Variables correlating significantly with CDS or PEP-Q, respectively, were included in a backward multiple regression to determine if these variables predicted the severity of the CDS or PEP-Q. All analyses were performed with PASW Statistics 19.0. 3. Results

2.3.7. Safety behaviours and post-event processing Safety behaviours were measured with an adapted version of the Social Behaviour Questionaire (SBQ; Clark et al., 1995). Stangier, Heidenreich, and Peitz (2003) developed a German version of the scale (which we will refer to as SBQ-G) and conducted tests of its psychometric properties. Reliability was moderate (Cronbach’s ˛ = .69) but can be considered sufficient as some of the symptoms are mutually exclusive. Convergent validity was supported via significant correlations of the SBQ-G and the Social Interaction Anxiety Scale (SIAS) at r = .36 and the Social Phobia Anxiety Scale (SPAI) at r = .34. For the purpose of this study, the test needed to be adapted. The instruction now referred directly to the test situation and only those 16 (out of 27) items which were applicable to the situation were selected. Cronbach’s ˛ for this shortened scale was as high as ˛ = .72 in a pre-study with n = 17 patients with SP and ˛ = .74 in n = 39 healthy controls undergoing the TSST. In this study, Cronbach’s ˛ was ˛ = .83 in SP and ˛ = .78 in the control group. The selected 16 items represent mental, physical and interactional safety behaviour. The Post-Event Processing Questionnaire (PEPQ; Rachman, Grueter-Andrew, & Shafran, 2000), originally a 13-item self-report measure, was applied in its 15-item German adaptation (Fehm et al., 2008) in which two items of the original PEP Questionnaire were split: Item 10, asking for the type of memory perspective (“If you thought about the event, did you see it from your point of view, or how other people would view it?”; field vs. observer perspective), was divided into two items, each asking for one memory perspective. Also Item 13 was split into two separate items, because it comprised two aspects of avoidance (“As a result of the event, do you now avoid similar events; did this event reinforce a decision to avoid similar situations?”). The German version of the PEP Questionnaire thus contained 15 instead of 13 items and showed overall favourable psychometric results (Fehm et al., 2008). The items were

3.1. Descriptive statistics As Table 1 indicates, the SP group exhibited higher scores in all measures of social anxiety and depression than the HC group. The heightened degree of social anxiety and depression is typical for patient samples of social phobia as, e.g., the samples of Clark et al. (2006), Cottreaux et al. (2000), or McManus et al. (2009). In terms of personality, the SP group displayed significantly higher scores in in NS and RD. The relatively high scores in NS are concordant with the view that the “high novelty seeking, impulsive subtype” of SP as described by Kashdan and Hofmann (2007) was highly prevalent in our sample. The relatively higher RD has also been previously described as typical for SP (Kashdan & Hofmann, 2007). All situational variables referring to the experience of the TSST indicate that the SP group perceived the situation as more stressful (with reference to primary appraisal of the situation), used more safety behaviours and experienced more DP/DR symptoms. Consequently, SP patients also engaged in more PEP during the week following the experiment. 3.1.1. Frequency of DP/DR symptoms As expected in Hypothesis 1, there were significantly more symptoms of DP/DR in social phobia patients than in controls. Furthermore, experience of DP/DR symptoms during the TSST was rather the rule than the exception in SP. 92.9% of the patients experienced one or more DP/DR symptoms of an at least moderate degree (defined as 33% or more on 0–100 scale) while 76.4% experienced at least one severe DP/DR symptom (defined as 66% or more on 0–100 scale). Also, the healthy control group experienced DP/DR during the TSST. In this group, however, 47.1% did not experience any moderate DP/DR at all, and 67.6% did not experience any severe DP/DR.

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Table 1 Means and standard deviations of all self-report measures in social phobia patients and healthy controls. Measure

SP

HC

n

M

SD

n

M

SD

LSAS SPAI BFNE BSPS SIAS SPS

55 52 53 49 54 55

67.60 3.76 32.57 34.68 41.01 28.82

19.85 .85 6.97 12.56 12.20 13.24

34 34 33 32 34 33

10.15 .84 13.18 3.69 11.26 4.21

7.46 .54 6.22 3.96 6.83 4.90

BDI

55

11.83

7.92

33

2.11

2.4

t

p

d

12.65 17.80 13.06 13.50 12.98 10.25

<.001** <.001** <.001** <.001** <.001** <.001**

3.56 3.97 2.93 3.11 2.87 2.28

6.83

<.001**

1.53

*

NS HA RD

55 55 55

19.33 22.76 16.33

3.88 3.77 3.63

33 33 33

18.12 20.85 14.64

2.89 4.61 3.34

1.54 2.12 2.22

.037 .126 .029*

.47 .35 .48

CDS CDSlog

55 55

4.63 .69

2.86 .23

34 34

1.95 .42

1.70 .21

4.93 5.62

<.001** <.001**

1.09 1.23

SBQ-G

53

38.73

9.70

29

29.24

8.70

5.73

<.001**

1.03

PA SA PEP-Q

54 52 45

3.76 2.57 36.24

.93 .61 19.10

33 33 25

2.25 3.57 10.36

.71 .56 7.45

8.02 −7.60 6.49

<.001** <.001** <.001**

1.79 −1.71 1.64

Notes: SP: patients with social phobia; HC: healthy controls; t: result of the t-test between SP and HC, p: p-value, d: Cohen’s d; ns: non-significant. LSAS: Liebowitz Social Anxiety Scale; SPAI: Social Phobia Anxiety Inventory; BFNE: Brief Fear of Negative Evaluation Scale; BSPS: Brief Social Phobia Scale; SIAS: Social Interaction Scale; SPS: Social Performance Scale; BDI: Beck Depression Inventory; NS: Novelty Seeking; HA: Harm Avoidance; RD: Reward Dependence; CDS: adapted state version of the Cambridge Depersonalization Scale (15 items); CDS log: logarithmized CDS-value; SBQ-G: Safety Behaviour Questionnaire; PA: Primary Appraisal; SA: Secondary Appraisal; PEP-Q: Post-Event-Processing-Questionnaire. * p < .05. ** p < .01.

These results indicate that the TSST, a test which has been found to reliably elicit an intense stress response, also reliably provokes DP/DR reactions in participants. Table 2 documents which symptoms are particularly frequent and which symptoms specifically differentiate between SP and HC. Relative to HC, SP showed a higher frequency of the following symptom domains: feelings of detachment of oneself from the world (Items 1 and 10), as well as from one’s own movements, body (Items 3, 4, 12, and 13), voice (Items 7 and 8), and thoughts (Item 14). Further, SP showed higher frequency of symptoms including sensory distortions of oneself (Items 5, 9, and 15) and the environment (Items 2 and 11), in addition to an absence of emotion (Item 6). 3.2. Correlates of DP/DR As Table 3 indicates, reporting of DP/DR symptoms is significantly associated with social anxiety and psychological variables within and after the situation such as appraisal, safety behaviours and post-event processing. There were no significant correlations between DP/DR and personality scales. As a tendency, correlation patterns appear to be distinct between both groups. In SP, significant positive correlations were found between DP/DR and BSPS (r = .386), SPS (r = .296), SBQ-G (r = .653), Primary Appraisal (r = .510), and PEP-Q (r = .646). In HC, the significant correlation between DP/DR and BSPSscores was higher (r = .518) whereas no significant correlations with SPS, SBQ-G and Primary Appraisal (PA) were found. The correlation between DP/DR and PEP-Q (r = .418) was slightly lower relative to SP. Further, HC showed significant correlations between DP/DR and SPAI (r = .523) and SIAS (r = .484). In order to explore whether the association between indicators of social anxiety and DP/DR was generally higher in healthy subjects, we calculated a composite score based on Z-transformed scores of all social anxiety measures of this study (see Clark et al., 2006) and analyzed whether the correlation between this composite score and DP/DR differed significantly between groups. The correlation between the composite score and DP/DR was insignificant (r = .216; p = .15) in the SP group and highly significant (r = .490;

p < .01) in the in the HC group. There was a statistical tendency indicating a difference between both correlation coefficients (z = 1.3; p = .097 one-tailed). 3.3. Predictors of DP/DR Given the differential patterns of correlations, it is not surprising that the significant predictors for DP/DR differed between SP and HC (see Table 4). In SP, SBQ-G scores (ˇ = .35, p = .009) and PEP-Q scores (ˇ = .45, p = .003) were found to be the strongest predictor of DP/DR, when the backward regression model (Adj. R2 = .54) was employed. In HC, SPAI-scores (ˇ = .57, p = .001) were found to be a significant predictor of DP/DR while the proportion of explained variance was generally smaller in this group (Adj. R2 = .31). 3.4. Predictors of post-event processing Additionally, we explored whether DP/DR show incremental validity over and above the other psychological variables of this research when predicting post-event processing during the week after the test situation (see Table 5). In SP, the backward model (Adj. R2 = .47) revealed CDSlog(ˇ = .57, p = < .001) and SPAI-scores (ˇ = .28, p = .036) to be significant and important predictors of post-event processing. In HC, only SPAI-scores (ˇ = .50, p = .011) were found to be significant as predictors of post-event processing when using the backward regression model (Adj. R2 = .22). 4. Discussion This research presents evidence that DP/DR symptoms occur highly frequently in social phobia when patients are confronted with socially demanding situations. Our data not only show that SP patients experience DP/DR more often than healthy control participants during a social performance situation, but also, more importantly, that DP/DR are closely related to processes known to maintain SP, such as safety behaviours and post-event-processing. Generally, these data argue for more research into the association

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Table 2 Means, SD and percentage of participants that experienced at least a moderate intensity in each depersonalization symptom in 54 patients and 34 healthy controls. Item

SP

HC

M

SD

%

M

SD

%

1. Out of the blue, I felt strange, as if I were not real or as if I were cut off from the world. 2. What I saw looked ‘flat’ or ‘lifeless’, as if I were looking at a picture. 3. Parts of my body felt, as if they didn’t belong to me. 4. Whilst being in the test situation, I had the feeling of being a ‘detached observer’ of myself. 5. My body felt very light, as if it were floating on air

54.20 35.24 22.87 34.62 18.44

32.5 32.9 26.2 32.4 20.7

65.5 41.8 25.5 43.6 20.0

21.59 27.85 9.88 13.35 14.76

23.91 33.1 17.5 21.8 22.9

14.7 32.2 8.8 11.8 11.8

6. I did not seem to feel any emotion at all. 7. Familiar voices (including my own) did sound remote and unreal. 8. I had the feeling of not having any thoughts at all, so that when I spoke it felt as if my words were being uttered by an ‘automaton’. 9. I had the feeling that my hands or my feet became larger or smaller. 10. My surroundings felt detached or unreal, as if there were a veil between me and the outside world.

32.55 41.27 72.76

31.9 33.9 27.6

34.5 47.3 89.1

16.09 17.00 29.12

20.7 20.7 23.9

17.6 11.8 35.1

9.11 35.78

14.2 69.3

3.6 34.4

5.09 7.76

5.5 15.0

0.0 2.9

11. In the current situation objects around me seemed to look smaller or further away. 12. I had the feeling of being outside my body. 13. When I moved it didn’t feel as if I were in charge of the movements, so that I felt “automatic” and mechanical as if I were a ‘robot’. 14. I felt detached from my thoughts that they seemed to have a ‘life’ of their own. 15. I had to touch myself to make sure that I had a body or a real existence.

12.11 20.40 29.32

18.0 27.8 29.1

5.5 20.0 34.5

4.82 6.21 8.18

5.1 11.3 13.0

0.0 2.9 2.9

28.98 14.85

33.1 21.71

32.7 12.7

9.35 4.29

16.2 4.3

5.9 0.0

Notes: Items of the adapted state version of the Cambridge Depersonalization Scale; % = the percentage of participants in each group that experienced an at least moderate intensity of the respective item. ‘Moderate’ was defined as scoring 33 or more on the 0–100 scale of the CDS.

between DP/DR symptoms and SP and for a more explicit integration of DP/DR into models of SP. In an effort to reduce recall and consistency biases, this study is the first to elicit DP/DR and measure them directly after a social performance situation. The TSST paradigm reliably produced DP/DR symptoms in nearly all social phobia patients, as well as about 50% of the healthy control group undergoing the situation. Experiencing of DP/DR during (putative) social evaluation appears to be the rule rather than the exception, at least in SP, a finding clearly emphasizing that these symptoms can contribute to the development and maintenance of the disorder. The frequency of DP/DR was significantly higher in SP than in the HC group, and the difference reached a high effect size of d > 1. When inspecting Table 1, it is clear that other variables, especially general social anxiety symptom scales, show even larger differentiation between the healthy and the SP group. However, it has to be acknowledged that the TSST is meant to activate strong

stress reactions in all participants, including those not suffering from social anxiety. Thus, the test may underestimate interpersonal variation across situations. The method once again proved its potential to provoke these reactions in our sample. Trait measures of DP/DR symptoms can be expected to reveal even larger differences between SP and healthy subjects (Michal et al., 2005). In order to evaluate the significance of DP/DR for the understanding of SP, we find it even more important that DP/DR were closely associated with two processes, which have been conceptualized as central components of the maintenance process of SP. Firstly, safety behaviours are defined as cognitive or behavioural strategies that are implemented in order to avoid negative evaluation by others (Clark & Wells, 1995). Simply put, this set of behaviours is initiated as a means to prevent the individual from experiencing higher anxiety and embarrassment. It is clear, e.g., that an individual with acute DP symptoms (e.g., whose mind goes blank), will stop giving an improvised talk and reach out

Table 3 Correlations between measures of social anxiety, depression, personality, and cognitive and behavioural characteristics of the stress situation and depersonalization symptoms during stress (CDSlog). Construct

Measure

SP

r with CDSlog

Social phobia

LSAS SPAI BNFE BSPS SIAS SPS

.211 .222 .019 .386** .138 .296*

55 52 53 49 54 55

.273 .523** .249 .518** .484** .287

34 34 33 32 34 33

Depression

BDI

.183

55

.254

33

Personality

Novelty Seeking Harm Avoidance Reward Dependence

−.024 −.116 .172

55 55 55

−.284 −.176 −.074

33 33 33

Safety behaviours

SBQ-G

.653**

53

.232

29

**

54 52 45

.313 −.258 .418*

33 33 25

n

Cognitive measures

Primary Appraisal Secondary Appraisal PEP-Q

.510 −.178 .646**

HC

n

Notes: SP: patients with social phobia; HC: healthy controls; LSAS: Liebowitz Social Anxiety Scale; SPAI: Social Phobia Anxiety Inventory; BFNE: Brief Fear of Negative Evaluation Scale; BSPS: Brief Social Phobia Scale; SIAS: Social Interaction Scale; SPS: Social Performance Scale; BDI: Beck Depression Inventory; CDSlog: logarithmized CDS-value; SBQ-G: Safety Behaviour Questionnaire; PEP-Q: Post-Event-Processing-Questionnaire. * p < .05. ** p < .01.

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Table 4 Predictors of CDS in n = 39 patients with social phobia and n = 32 healthy controls (HC). CDS in SP R2 Model 1 BSPS SPS SBQ-G PA PEPQ

.60

Model 2 SPS SBQ-G PA PEPQ

.60

Model 3 SBQ-G PA PEPQ

.59

Model 4 SBQ-G PEPQ

.57

CDS in HC R2

ˇ

p Model 1 SPAI BSPS SIAS

.39

−.03 −.09 .39 .21 .38

<.001 .908 .651 .069 .167 .017 <.001 .560 .054 .146 .015

Model 2 SPAI BSPS

.39

−.10 .382 .208 .38

<.001 .043 .146 .013

Model 3 SPAI

.33

.31 .21 .38 .35 .45

.009 .003

−.01

R2

R2

ˇ

p

.32 .28 .12

.003 .210 .137 .608

.41 .29

.001 .026 .115

.57

.001 .001

<−.01

−.06

−.03

Notes: Measures correlating significantly with CDS were included in regression models; p: p-value, ˇ: beta; CDS: logarithmized CDS-value; BSPS: Brief Social Phobia Scale; SPS: Social Performance Scale; BDI: Beck Depression Inventory; SBQ-G: Safety Behaviour Questionnaire; PA: Primary Appraisal. Adjusted R2 ’s for SP group: Model 1 = .54, Model 2 = .55, Model 3 = .56 and Model 4 = .54; for HC group: Model 1 = .33, Model 2 = .34, and Model 3 = .31.

Table 5 Predictors of post-event-processing n = 37 patients with social phobia and n = 25 healthy controls (HC). CDS in SP 2

R Model 1 CDS LSAS SPAI BSPS SPS SBQ-G PA

.54

Model2 CDS SPAI BSPS SPS SBQ-G PA

.54

Model 3 CDS SPAI BSPS SPS SBQ-G

.54

Model 4 CDS SPAI SPS SBQ-G

.53

Model 5 CDS SPAI SPQ-G

.52

Model 6 CDS SPAI

.50

CDS in HC R

2

ˇ

R2

p Model 1 CDS SPAI SIAS

.30

.41 −.02 .25 .12 −.19 .24 .07

.001 .024 .903 .171 .642 .385 .301 .670 .001 .021 .146 .636 .366 .295 .669

Model 2 CDS SPAI

.30

.41 .24 .11 −.20 .24 .07

<.001 .011 .137 .507 .319 .278

Model 3 SPAI

.25

.43 .24 .15 −.21 .25 .45 .28 −.16 .30

<.001 .007 .076 .407 .148

.47 .22 .20

<.001 .005 .111 .229

.57 .28

<.001 <.001 .036

<−.01

<−.01

−.01

−.02

−.04

R2

ˇ

p

.25 .36 .04

.054 .244 .212 .880

.25 .39

.020 .222 .061

.50

.011 .011

<.01

.05

Notes: Measure correlating significantly with PEP-Q were included in regression models; p: p-value; ˇ: beta-weights; PEP-Q: post-event-processing; CDS: logarithmized CDS-value; LSAS: Liebowitz Social Anxiety Scale; SPAI: Social Phobia Anxiety Inventory; BSPS: Brief Social Phobia Scale; SPS: Social Performance Scale; BDI: Beck Depression Inventory; SBQ-G: Safety Behaviour Questionnaire; PA: Primary Appraisal; SIAS: Social Interaction Scale. Adjusted R2 ’s for SP group: Model 1 = .43 and Model 6 = .47; for HC group: Model 1 = .20, and Model 3 = .22.

J. Hoyer et al. / Journal of Anxiety Disorders 27 (2013) 178–187

for a written manuscript instead, if possible. Hence, experiencing DP/DR may actually provoke the engagement of safety behaviours. However, we are unable to confirm the assumption that DP/DR generally trigger subsequent safety behaviours, as the association found is of correlational nature. This would imply that safety behaviours, especially their cognitive variants, may also be so demanding for information processing that DP/DR will follow as a consequence (rather than act as their source): Continuously monitoring one’s own speech, e.g., may seriously compromise the person’s working memory and lead to DP/DR symptoms. A question that to date remains unsolved refers to the nature of the relation between DP/DR symptoms and the attention shift from field to observer perspective in social phobia: do they refer to one and the same or two different, but potentially related processes? Tentatively, it may be hypothesized that DP/DR and the self-focused attention using an observer perspective vary on a continuum as a function of the experienced level of arousal. The notion that they are closely related may be supported by their shared features, which involve a shift in attention from the habitual field perspective. Moreover, both phenomena may be experienced aversively, thus possibly motivating the engagement in safety behaviours. Hence, DP/DR may represent extreme conditions of an attention-shift, during which anxiety has reached levels which are high and in need of regulation. Furthermore, DP/DR may also lead to enhanced post-eventprocessing. It has to be emphasized that the moderate to high positive correlation that we found between DP/DR and PEP (r = .646) is based on longitudinal data, as measurement of DP/DR preceded PEP, which was measured one week later. Hence it is plausible that the experience of DP/DR specifically prompts the individuals’ belief that he or she performed incompetent during the TSST and was perceived accordingly by others. In order to cope with this problematic self-perception prolonged information processing (PEP) becomes specifically probable. Again, because we did not directly manipulate DP/DR, we cannot exclude the interpretation that DP/DR and PEP are only associated due to third variables that we could not control statistically (as we did, however, for social anxiety and depression). Interestingly, the correlation between DP/DR and safety behaviours was only high and significant in the SP group but not in the HC group. From a statistical perspective, this result may simply be due to the lower variability in safety behaviours as well as in DP/DR symptoms in healthy participants. This statistical pattern still reflects an important psychological difference between the groups: Healthy participants appraise the stress situation as less threatening than social phobia patients and only engage in minimal safety behaviour and also less DP/DR. On the other hand, when analyzing the correlations between (acute) DP/DR and measures of social anxiety, there was a reverse pattern with high (and mostly significant) correlations in the healthy group and low (and mostly insignificant) correlations in the patient group. One interpretation of this finding is that DP/DR symptoms generally occur more frequently the higher the social anxiety is but only until a certain (pathological) threshold of social anxiety has been reached. Beyond this threshold, DP/DR symptoms become so typical that the covariation with social anxiety is only weak if at all existent. In other words, the correlation of DP/DR and social anxiety is moderated by the severity of the social anxiety symptoms. This is in full concordance with the proposed defensive function of DP/DR (Sierra, Medford, Wyatt, & David, 2012). Accordingly, DP/DR symptoms can be considered markers of severe acute states of social anxiety. Taken together, our findings are consistent with the view that social phobia patients experience DP/DR in higher frequency and intensity during stressful social interactions; that they more intensively initiate safety behaviours in order to reduce the experience of

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DP/DR; and that they engage in prolonged PEP to be able to accommodate to the experience of DP/DR at a later time. On the other hand, PEP is known to contribute to the maintenance of SP, due to the fact that PEP cognitive content and related affect is influenced by anxious feelings and negative self-perceptions that were processed during the stressful event itself, hence becoming strongly encoded in memory (Clark & Wells, 1995). As a result, PEP becomes negatively biased and the social interaction is remembered as being more negative than it actually was (Fehm et al., 2007). The biased memory of the social interaction thus reinforces negative perceptions of oneself and of social interactions, which in turn may be activated by social-threat cues (Wenzel, Jackson, & Holt, 2002) and influence the processing of future encounters (Clark & Wells, 1995). As these are only initial data studying DP/DR in situ in SP, our findings require replication. Furthermore a number of methodological questions remain open and a number of limitations need to be mentioned: first of all, the measurement of DP/DR could only be conducted via self-report including the respective biases of such research methodology. Furthermore, an open question remains as to what degree DP/DR symptoms were experienced as debilitating, how they were subjectively appraised in general and whether they interfered with social performance. Additionally, it has to be mentioned that our sample may not be fully representative for all SP patients seeking help as a number of patients did not agree to participate in the study or in the TSST (14%, n = 9). Furthermore, our SP sample was characterized by higher Novelty Seeking than the HC sample (a finding which not necessarily unexpected given previous findings by Kashdan & Hofmann, 2007). However, in our view, the finding of DP/DR as typical symptoms of SP is not compromised by this potential selection bias. Those who did not partake would even be expected to exhibit more DP/DR during socially evaluative situations, as they avoided exactly such a situation. Another limitation is that all findings are based on a controlled laboratory setting and that participants were well informed (as they had to be) that the situation would elicit social stress. How these specific findings transfer to naturalistic experiences of SP, when social stress cannot be as clearly anticipated, remains to be examined. Finally, it was observed that Item 8 (“I had the feeling of not having any thoughts at all, so that when I spoke it felt as if my words were being uttered by an ‘automaton’.”) produced exceptionally large differences between the SP and HC groups (d = 1.69). This may raise the suspicion of a method bias in relation to the word “automatic”. However, because the other item containing the term “automatic” (Item 13) did not produce a similarly large between-group difference (d = 0.94) and was comparable to other items of the CDS (state version), it appears safe to rule-out such bias. Nevertheless, given its detrimental effects on the interpretation of the results (Podsakoff, MacKenzie, & Podsakoff, 2003), future studies may consider item wording as a potential source of method bias an apply techniques for increased control (e.g., testing parallel format conditions). Nevertheless, beyond these limitations a number of promising research questions become obvious. To mention a few, it would be of interest to understand how DP/DR are linked to open and implicit avoidance of SP patients; whether DP/DR are linked to (potential) sub-types of SP; and how susceptible DP/DR are to specific variants of treatment. Attention training, as described by Clark and Wells (1995) and even more elaborately by Bögels (2006; see also Chaker, Hofmann, & Hoyer, 2010, for an application study), seems to be a prime candidate for an intervention that could help counteract the experience of acute DP/DR. In summary, this research presents strong evidence for a more rigorous integration of DP/DR into models of social phobia. Given that DP/DR are per definition “unusual” experiences referring to states that are not commonly experienced and are rather “exceptional” in nature, it is clear that SP would not mention DP/DR

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among their primary concerns during social situations. It is probable that they try to avoid situations provoking DP/DR as to the largest possible extent. However, this may not signify that DP/DR are unimportant for the understanding of SP. On the contrary, more research investigating DP/DR and related experiences in SP is highly demanded. Finally, there is one idea that we would especially like to highlight: Although CBT has been shown to be highly efficacious in the treatment of SP, particularly when conducted based on the ClarkWells model of SP (Clark et al., 2003, 2006), a relevant number of patients do not reach a clinical significant response to treatment (see, e.g., Blanco et al., 2010; Davidson et al., 2004; Powers, Sigmarsson, & Emmelkamp, 2008). It is unlikely that a single variable can explain why some patients cannot benefit from treatment. However, those patients who have a strong tendency to experience DP/DR symptoms during role plays and behavioural experiments would at least experience a definitive psychological barrier to pronounced treatment success. Role plays and behavioural experiments in social situations are an integral part of the procedures proposed by Clark and Wells (1995). The notion that patients fear experiencing DP/DR during role plays and/or behaviour experiments would explain why they cannot fully, i.e., without open or implicit safety behaviours, engage in such interventions. Further research should therefore specifically test the hypothesis that fear of DP/DR defines a specific hindrance to benefit from CBT treatment. Conflict of interest statement JH received speaking honoraria from Astra-Zeneca. The other authors of the present article declare that they have no competing interests. Role of funding source This work (including data collection, analysis, interpretation of the data, and writing of the report) was supported by a grant from the Deutsche Forschungsgemeinschaft (HO1900/6-1 and KI 537/26-1) and a scholarship from Evangelisches Studienwerk eV Villigst to EK. References Abbott, M. J., & Rapee, R. M. (2004). Post-event rumination and negative selfappraisal in social phobia before and after treatment. Journal of Abnormal Psychology, 113(1), 136–144. Ackner, B. (1954). Depersonalization. I: aetiology and phenomenology. Journal of Mental Science, 100(1), 838–853. American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders DSM-IV-TR (4th edition (text revision)). Washington: APA. Ball, S., Robinson, A., Shekhar, A., & Walsh, K. (1997). Dissociative symptoms in panic disorder. The Journal of Nervous and Mental Disease, 185(12), 755–760. Beck, A. T., Ward, C. H., Mendelson, M., Mock, M., & Erbaugh, J. (1961). An inventory for measuring depression. Archives of General Psychiatry, 4(6), 561–571. Bernstein, E., & Putnam, F. W. (1986). Development, reliability, and validity of a dissociation scale. Journal of Nervous and Mental Disease, 174(12), 727–735. Blanco, C., Heimberg, R. G., Schneier, F. R., Fresco, D. M., Chen, H., Turk, C. L., et al. (2010). A placebo-controlled trial of phenelzine, cognitive behavioral group therapy and their combination for social anxiety disorder. Archives of General Psychiatry, 67(3), 286–295. Bögels, S. M. (2006). Task concentration training versus applied relaxation, in combination with cognitive therapy, for social phobia patients with fear of blushing, trembling, and sweating. Behavior Research and Therapy, 44(8), 1199–1210. Bryant, R. A. (2007). Does dissociation further our understanding of PTSD? Journal of Anxiety Disorders, 21(2), 183–191. http://dx.doi.org/10.2466/ pr0.1991.69.3.1047 Cassano, G. B., Petracca, A., Perugi, G., Toni, C., Tundo, A., & Roth, M. (1989). Depersonalization and panic attacks: a clinical evaluation on 150 patients with panic disorder/agoraphobia. Comprehensive Psychiatry, 30(1), 5–12. Chaker, S., Hofmann, S. G., & Hoyer, J. (2010). Can a one-weekend group therapy reduce fear of blushing? Results from an open trial. Anxiety, Stress & Coping, 23(3), 303–318.

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