Biased Perception of Physiological Arousal in Child Social Anxiety Disorder Before and After Cognitive Behavioral Treatment


Research Articles

Biased Perception of Physiological Arousal in Child
Social Anxiety Disorder Before and After Cognitive
Behavioral Treatment

Julia Asbrand ab, André Schulz c, Nina Heinrichs d, Brunna Tuschen-Caffier a

[a] Institute of Psychology, Albert Ludwigs University of Freiburg, Freiburg, Germany. [b] Institute of Psychology,
Humboldt-Universität zu Berlin, Berlin, Germany. [c] Clinical Psychophysiology Laboratory, Institute for Health and
Behaviour, University of Luxembourg, Esch-sur-Alzette, Luxembourg. [d] Department of Psychology, University of
Bremen, Bremen, Germany.

Clinical Psychology in Europe, 2020, Vol. 2(2), Article e2691, https://doi.org/10.32872/cpe.v2i2.2691

Received: 2020-01-16 • Accepted: 2020-03-11 • Published (VoR): 2020-06-30

Handling Editor: Cornelia Weise, Philipps-University of Marburg, Marburg, Germany

Corresponding Author: Julia Asbrand, Department of Child and Adolescent Clinical Psychology and
Psychotherapy, Institute of Psychology, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099 Berlin, Germany.
Phone: +49 30 2093 9334. E-mail: julia.asbrand@hu-berlin.de

Abstract
Background: A biased perception of physiological hyperreactivity to social-evaluative situations
is crucial for the maintenance of social anxiety disorder (SAD). Alterations in interoceptive
accuracy (IAc) when confronted with social stressors may play a role for SAD in children. We
expected a biased perception of hyperarousal in children with SAD before treatment and,
consequently, a reduced bias after successful cognitive behavioral therapy (CBT).
Method: In two centers, 64 children with the diagnosis of SAD and 55 healthy control (HC)
children (both 9 to 13 years) participated in the Trier Social Stress Test for Children (TSST-C),
which was repeated after children with SAD were assigned to either a 12-week group CBT (n = 31)
or a waitlist condition (n = 33). Perception of and worry about physiological arousal and autonomic
variables (heart rate, skin conductance) were assessed. After each TSST-C, all children further
completed a heartbeat perception task to assess IAc.
Results: Before treatment, children with SAD reported both a stronger perception of and more
worry about their heart rate and skin conductance than HC children, while the objective reactivity
of heart rate did not differ. Additionally, children with SAD reported heightened perception of and
increased worry about trembling throughout the TSST-C compared to HC children, but reported
increased worry about blushing only after the stress phase of the TSST-C compared to HC children.
Children with and without SAD did not differ in IAc. Contrary to our hypothesis, after treatment,
children in the CBT group reported heightened perception of physiological arousal and increased
worry on some parameters after the baseline phase of the TSST-C, whereas actual IAc remained
unaffected. IAc before and after treatment were significantly related.

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Conclusions: Increased self-reported perception of physiological arousal may play a role in
childhood SAD and could be an important target in CBT. However, further studies should examine
if this is an epiphenomenon, a temporarily occurring and necessary condition for change, or indeed
an unwanted adverse intervention effect.

Keywords
bodily arousal, social phobia, CBT, therapy, interoceptive awareness, heartbeat perception

Highlights
• Biased perception of physiological arousal may play a role in child social

anxiety disorder (SAD).
• Faced with standardized social stress, biased perception of heart rate but not

skin conductance.
• No change in biased perception due to cognitive-behavioral treatment.
• Further research regarding the nature of biased perception (e.g.

epiphenomenon) necessary.

Social anxiety disorder (SAD) is a highly prevalent disorder (Burstein et al., 2011) that
leads to great impairment in the well-being and everyday life of affected children (Rao
et al., 2007). Cognitive models of SAD (e.g., Clark & Wells, 1995) point to the importance
of an increased focus on cognitions, feelings, and behaviors. In addition, a person with
SAD is also alarmed by physiological reactions in social situations. In line with cognitive
models, the subjective awareness of physiological and emotional arousal is interpreted
negatively, which leads to an overall negative self-perception followed by elevated fear of
and avoidance of social situations.

A (physiological) anxiety reaction was required in the Diagnostic and Statistical Man‐
ual for Mental Disorders (4th ed., text rev.; DSM-IV-TR; American Psychiatric Association
[APA], 2000). This has been revised in the latest version, allowing to display any sign
of fear, not necessarily physiologically (DSM-5, APA, 2013). This change reflects that the
objective physiological reaction is not yet fully understood: Several studies have shown
tonic hyperarousal in children with SAD (Asbrand, Blechert, Nitschke, Tuschen-Caffier,
& Schmitz, 2017; Krämer et al., 2012; Miers, Blöte, Sumter, Kallen, & Westenberg, 2011;
Schmitz, Tuschen-Caffier, Wilhelm, & Blechert, 2013). However, research has failed to
find heightened physiological reactivity to disorder-typical stress (for an overview see
Siess, Blechert, & Schmitz, 2014). Still, both children and adults with SAD have reported
increased perception of physiological arousal (Gerlach, Mourlane, & Rist, 2004; Schmitz,
Blechert, Krämer, Asbrand, & Tuschen-Caffier, 2012). Therefore, it has been hypothesized
that cognitive factors (e.g., attention allocation and evaluation) are also relevant for
physiological factors. That is, people with SAD are more prone to shift their attention
towards physiological arousal and evaluate this arousal as more threatening (Clark &

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Wells, 1995; Siess et al., 2014). Attentional biases have previously been examined mostly
for external cues, such as angry versus happy faces, with measures of reaction times or
with eye tracking (for an overview in adults see Bar-Haim, Lamy, Pergamin, Bakermans-
Kranenburg, & van Ijzendoorn, 2007). Similar to studies of adults, a meta-analysis of
anxious compared to nonanxious children (Dudeney, Sharpe, & Hunt, 2015) showed a
significant attentional bias to threat. While these findings on external attentional biases
are in line with Rapee and Heimberg's (1997) theoretical model of SAD, the importance
of other biases, also suggested by current cognitive models (e.g., Clark & Wells, 1995;
Rapee & Heimberg, 1997) have received less attention, specifically internal perceptional
biases. The processing of internal perceptional information is likely dependent upon their
(believed) visibility for others:

Certain internal symptoms (e.g. increased heart rate, nausea) are relevant for the
experience of anxiety in general but are not overly visible (cognition: “My heart is racing,
this must mean that I am anxious”). However, other physiological symptoms are clearly
visible (e.g. blushing, sweating, trembling) and are, therefore, extremely relevant for the
fear of being judged (cognition: “I am blushing, others can see how anxious I am”). As
such, these physiological symptoms are relevant for the experience of SAD specifically.
One previous study in children aged 10 to 12 years with high versus low social anxiety
(Schmitz et al., 2012) manipulated heart rate visibility by applying a heart rate feedback
tone while children told a story in a “private” condition (head phones) and a “public”
condition (with adult observers present). Children with high social anxiety perceived
their heart rate as higher than low socially anxious children when they listened to their
(supposedly own) heart rate both in private and in public with adult observers present.
Further, the public condition led to more worry about the heart rate visibility only in
children with high social anxiety. This study demonstrated that both perception of and
worry about visibility of physiological arousal (i.e. evaluation) is elevated in socially
anxious children. As this study examined a subclinical sample, it is necessary to assess
children with SAD to assure the stability of this phenomenon in clinically affected
children. Additionally, as the study used a set-up specific to perception of and worry
about heart rate, it should be tested if this finding is stable in a well-established social
stress test, the Trier Social Stress Test for Children (TSST-C; Buske-Kirschbaum et al.,
1997) and using more than one physiological parameter (Siess et al., 2014).

To reveal the underlying processes of biased perception in children with SAD, it is
required to assess different facets of interoception: First, ‘interoceptive accuracy’ (IAc)
represents the correspondence between actual and perceived physical signals (e.g., heart‐
beats). Second, the subjective tendency to be focused on physical signals is considered
‘interoceptive sensibility’ (IS) (Garfinkel, Seth, Barrett, Suzuki, & Critchley, 2015). Third,
‘interoceptive evaluation’ (IE) reflects subjective affective valence of physical sensations
such as worry about visibility (Pollatos & Herbert, 2018). While the attentional biases
refer more closely to IS and IE, IAc should be additionally considered. The heartbeat

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counting task (HCT) has been established as most common approach to assess cardiac
IAc in adults and in school children with and without anxiety symptoms (Eley, Gregory,
Clark, & Ehlers, 2007; Eley, Stirling, Ehlers, Gregory, & Clark, 2004; Georgiou et al.,
2015; Koch & Pollatos, 2014; Schandry, 1981; Schmitz et al., 2012). For example, Antony
et al. (1995) assessed IAc based on HCT and heart rate (HR) in adult patients with
panic disorder and SAD compared to healthy controls (HC). Groups did not differ in
IAc at rest or after exercise. However, self-reported anxiety was positively related to
IAc. In a child community sample (Eley et al., 2004), children between 8 and 11 years
completed the HCT. After a distinction into good and poor heartbeat perceivers based on
IAc scores, good perceivers reported significantly higher panic and/or somatic symptoms
and were more sensitive to anxiety. Similarly, higher levels of panic and/or somatic
symptoms were positively related to IAc. Both findings suggest that a proper perception
of physical sensations (IAc) enhances their interpretation as potentially threatening (IE)
in SAD. Furthermore, Schmitz et al. (2012) did not find differences in IAc based on the
HCT between children with high and low social anxiety, which implies that IAc and IE
may dissociate under specific circumstances. The authors assume that socially anxious
children overestimate their HR under stress (i.e. over-reporting of cardiac sensations) but
are able to perceive their heartbeat correctly in the recovery period after stress (Mauss,
Wilhelm, & Gross, 2004; Pollatos, Traut-Mattausch, Schroeder, & Schandry, 2007). In
summary, the role of IAc, IS and IE (including over-reporting of cardiac sensations) in
fully manifested SAD remains unclear.

If biased perception (IS) and evaluation (IE) of physiological symptoms and/or IAc
are central factors in childhood SAD, a longitudinal assessment measuring stability and
changeability by treatment is a plausible next step (e.g., Siess et al., 2014). Once again,
previous research focused on treatment effects on other biases, for example, interpreta‐
tion biases (Leigh & Clark, 2018). However, theoretical models placed the misperception
of physiological symptoms as central for SAD (e.g., Clark & Wells, 1995), which leads
to the assumption that cognitive behavioral therapy (CBT) might change this perception
bias. Interestingly though, most treatments of SAD do not explicitly focus on a biased
perception of physiological symptoms but rather on general cognitions in and after
social situations and on behavior in children (e.g., Beidel & Turner, 2007). However, as
pointed out above, the importance of including specific treatment components targeting
physiological reactions cannot be fully supported by empirical evidence, as findings on
physiological hyperarousal are inconsistent (Siess et al., 2014).

The Current Study
On objective measures (heart rate, electrodermal activity [EDA]), we expected children
with SAD to show only tonic hyperarousal and no increased reactivity to social stress
compared to children in a healthy control (HC) group (Asbrand et al., 2017; Schmitz et
al., 2013). On subjective measures, we expected all children to report perception (i.e. IS)

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of and worry (i.e. IE) about physiological variables (heart rate, perspiration, blushing,
trembling)1 that increases from baseline to stress and then decreases to recovery. This
effect, that is, heightened perceived reactivity, has been hypothesized to be stronger in
children with SAD compared to HC children (Schmitz et al., 2012). In line with previous
findings, we expect a positive correlation between physiological activation (e.g., heart
rate) and IAc. After children with SAD were assigned to a treatment (group CBT) or
waitlist control (WLC) group, we expected only small differences in objective measures
(heart rate, EDA) on a second TSST-C. We expected differences in subjective measures,
i.e. children in the CBT group reporting less perception of and worry about physiological
variables compared to children in the WLC group and compared to results of the TSST-C
before treatment.

M e t h o d

Trial Design
The study was designed as a randomized controlled trial (block randomization, in which
half of the participants were allocated by drawing from a hat to an experimental condi‐
tion receiving immediate treatment and half to a WLC condition receiving treatment
about 16 weeks later; for an overview see Figure 1). Randomization for each research
center was conducted in a concealed fashion by the other center, based on subject codes,
as soon as there were enough participants for one experimental and one WLC allocation.
Eligibility criteria were registered with the German Research Foundation (TU 78/5-2,
HE 3342/4-2) prior to recruitment and not changed during the study. This study was
part of a larger project. The overall project consisted of experimental studies related
to research questions of visual attention allocation or psychophysiological processes
under (social) stress and it also aimed to measure treatment success by including several
outcome variables (state anxiety, negative cognitions, physiological arousal, perception
of and worry about physiological symptoms, perception of academic performance, neg‐
ative post-event processing, parental cognitions, parental fear of negative child evalua‐
tion, and related treatment outcome predictions). Due to the extent of the project and
limitations on length and foci in articles, not all treatment related results could be
reported in a single manuscript. Further results are reported elsewhere (treatment out‐
come, Asbrand, Heinrichs, Schmidtendorf, Nitschke, & Tuschen-Caffier, 2020; changes in
post-event processing based on treatment, Asbrand, Schmitz, et al., 2019; stability of the
cortisol response despite treatment, Asbrand, Heinrichs, Nitschke, Wolf, Schmidtendorf,

1) Heart rate and perspiration were chosen to be assessed objectively as well. While the project further included
other physiological variables (e.g. cortisol; Asbrand, Heinrichs, Nitschke, Wolf, Schmidtendorf, & Tuschen-Caffier,
2019), these do not have a subjective counterpart which can be assessed by self-report. Due to technical limitations,
we could not assess blushing and trembling as objective parameters.

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Figure 1

Flowchart of Study Participants

Note. n1 = Center 1, n2 = Center 2; CBT = cognitive behavioral therapy; EDA = electrodermal
activity; HC = healthy control; HR = heart rate; SAD = social anxiety disorder; TSST-C = Trier
Social Stress Test for Children; WLC = waitlist control.

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& Tuschen-Caffier, 2019) or are being prepared for submission (social performance,
detailed psychophysiological activity pre and post treatment).

To ensure maximal transparency, all articles include cross-references to other reports
on measures used to investigate potential treatment-related effects. The current study
reports primary outcome variables relating to perception of (IS) and worry about phys‐
iological symptoms heart rate and EDA (IE). The inclusion of subjective perception of
and worry about blushing and trembling as well as cardiac IAc was included post-hoc.
The sample size for the current study, based on a medium to large effect (Schmitz et al.,
2012) and power of (1 - β) = .80, was set at n = 90 (each group n = 45). As the study
was part of a larger research project (see footnote) requiring a larger sample size of n =
110, all children were included to increase power. Because the data are being used in a
large project, this Method section has been reported before in a similar fashion (Asbrand,
Heinrichs, et al., 2019; Asbrand, Schmitz, et al., 2019).

Participants
We informed parents of anxious children (9 to 13 years) through advertisements in
schools, medical facilities, and newspapers in two midsized German cities from January
2012 to November 2013 until the targeted sample size had been reached (for an overview
see Figure 1). No harms were reported. Parents received €35, and children €25 in vouch‐
ers in compensation for participation in the laboratory study. Ethical approval for this
study was granted by an independent ethics committee (ethics committee of the German
Society for Psychology). All participating children and their caregivers consented to
participation in both oral and written form.

Inclusion criterion for children consisted of SAD as a primary diagnosis in the SAD
group and no current or lifetime diagnosis of a mental disorder in the HC group. Exclu‐
sion criteria entailed health problems or medication which could have interfered with
psychophysiological assessment (e.g., asthma, cardiac arrhythmia, and methylphenidate).
As can be seen in Table 1, the groups did not differ in age, type of school, or any of the
disorder-specific measures. Social Phobia and Anxiety Inventory for Children (SPAI-C)
scores exceeded suggested cut-offs for clinically relevant SAD.

Table 1

Participant Characteristics of the Experimental Groups (Social Anxiety Disorder vs. Healthy Controls)

Characteristic

Group

StatisticsSAD Healthy controls

n a 64 55
Mean age (SD), in years 11.3 (1.4) 11.3 (1.4) t(117) = 0.06, n.s.
Female 63.6% 60.0% χ2(1) = 0.17, n.s.
Mean SPAI-C (SD) 23.3 (9.03) 4.2 (5.4) t(117) = -13.71***

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Characteristic

Group

StatisticsSAD Healthy controls

Net income (per month) χ2(8) = 11.42, n.s.
n.a. 0% 1.3%
< €1,000 0% 5.9%
€1,001–1,500 1.9% 7.4%
€1,501–2,000 11.1% 8.8%
€2,001–3,000 35.2% 32.4%
€3,001–4,000 14.8% 16.2%
€4,001–5,000 14.8% 20.6%
> €5,000 22.2% 7.4%

Mean (SD) state anxiety during TSST-C (before treatment) 6.6 (2.8) 4.5 (2.9) t(117) = 4.05***
Note. Table adapted from Asbrand, Schmitz, et al. (2019). Reprinted with permission. SPAI-C = Social Phobia
and Anxiety Inventory for Children; TSST-C = Trier Social Stress Test for Children; n.a. = not available.
aSample sizes differ as not all questionnaires were completed correctly.
***p ≤ .001, n.s. = not significant.

Further, in the SAD group, children in the two conditions (CBT vs. WLC) did not differ in
sociodemographic and psychopathological variables (see Table 2).

Table 2

Participant Characteristics of Children With Social Anxiety Disorder Allocated to the Treatment Versus Waitlist
Group

Characteristic

Group

StatisticsTreatment (CBT) Waitlist control

n a 31 33
Mean age (SD), in years 11.5 (1.4) 11.2 (1.3) t(62) = 0.78, n.s.
Female 51.6% 67.6% χ2(2) = 1.88, n.s.
Mean SPAI-C (SD) 11.8 (7.3) 12.1 (7.1) t(62) = 0.18, n.s.
Net income (per month) χ2(7) = 6.65, n.s.

n.a. 3.2% 0.0%
< €1,000 6.5% 5.6%
€1,001–1,500 9.7% 5.6%
€1,501–2,000 6.5% 8.3%
€2,001–3,000 41.9% 23.7%
€3,001–4,000 16.1% 16.7%
€4,001–5,000 9.7% 30.6%
> €5,000 6.5% 8.3%

Mean (SD) state anxiety during TSST-C (before treatment) 6.7 (2.9) 6.6 (2.8) t(62) = 0.10, n.s.
Note. Table adapted from Asbrand, Schmitz, et al. (2019). Reprinted with permission. CBT = Cognitive behavio‐
ral therapy; n.a. = not available; SPAI-C = Social Phobia and Anxiety Inventory for Children; TSST-C = Trier
Social Stress Test for Children.
aSample sizes differ as not all questionnaires were completed correctly.
***p ≤ .001. n.s. = not significant.

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Procedure
The study took place at two German universities. All analyses first considered site differ‐
ences, which were non-existent. Following a short telephone screening for anxiety symp‐
toms, eligible children and their parents attended a diagnostic session (see flowchart in
Figure 1). Both the child and a parent separately participated in the Kinder-DIPS, a struc‐
tured interview that codes for mental disorders in children and adolescents (Schneider,
Unnewehr, & Margraf, 2008). Diagnoses of SAD and comorbid disorders (DSM-IV-TR,
APA, 2000) were then reached through combining both interviews, supervised by an
experienced clinical psychologist. Diagnoses were assigned under supervision of the
same licensed clinical psychologists per site throughout the project (one psychologist
at the first, two psychologists at the second center). The Kinder-DIPS is a validated
interview for the most frequent mental disorders in children and adolescents (Schneider
et al., 2008). The Kinder-DIPS is conducted by trained interviewers and the diagnosis
is usually based on both child and parent reports. The authors have reported adequate
interrater reliability (87% for anxiety disorders), good retest reliability (Schneider et
al., 2008), and successful validation with disorder-specific questionnaires. Additionally,
children and parents reported sociodemographic data, anxiety symptoms, and general
psychopathology in online questionnaires. According to the diagnostic assessment, 65
children fulfilled the inclusion criterion of a primary diagnosis of SAD; 55 children were
included in the HC group.

After the diagnostic interviews children participated in the first laboratory session,
the TSST-C (Buske-Kirschbaum et al., 1997), which consists of a speech and a math task
(see Figure 2). In the speech task, children narrate a story in front of two observers after
listening to the beginning of the story. In the following mental arithmetic task, children
were asked to serially subtract the number 7 from 758 (9- to 11-year-olds) or the number
13 from 1,023 (12- to 13-year-olds) as fast and as accurately as possible again in front
of two observers. Both observers were instructed and trained to give neutral verbal and
nonverbal feedback. The TSST-C elicits high social-evaluative stress in children (cf. Allen
et al., 2017). Throughout the session, heart rate and skin conductance level were assessed.
Further, perception of (IS) and worry about physiological symptoms (IE) were assessed
after baseline, stress, and recovery (see Figure 2). After a recovery period, children per‐
formed the HCT to assess IAc (see below). As the current project focused on the climax
of social stress, only this time of measurement was included in the analyses. Assessments
of perception and worry were based on a previous study (Schmitz et al., 2012): Children
were asked to rate their perceived level of physiological intensity during the task (e.g.,
“How strongly did you feel your heartbeat during the task?”) and their worry about their
physiological symptoms (“How much did you worry that others could notice how fast
your heart was beating?” on a scale of 0 (not at all) to 10 (extremely). After participating
in a 12-week CBT program (CBT group) or waiting without treatment (WLC group), all
children performed a parallel version of the first testing session. Based on the original

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TSST-C (Buske-Kirschbaum et al., 1997), the speech task was changed to a different story
that was judged to be similarly interesting and difficult in a preevaluation. The math task
was changed to a different start number (+10). The TSST-C reliably induces social anxiety
in all children, even more so in children with SAD compared to healthy control children,
p < .001.

Figure 2

Overall Procedure Including the Trier Social Stress Test for Children (TSST-C) Before (TSST-C 1) and After (TSST-C
2) Treatment or Waiting

Note. Physio perception 1–3 refers to measurements of participants’ perceived level of
physiological intensity and physio worry 1–3 to worry about their physiological symptoms.

Treatment
Treatment consisted of an exposure-based CBT treatment that was evaluated simultane‐
ously (Asbrand, Heinrichs, Schmidtendorf, Nitschke, & Tuschen-Caffier, 2020). It targets
dysfunctional cognitions, possible social deficits, and social avoidance with a strong

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focus on exposure. Each session consisted of 100 min (including a 10-min break) in
groups of five to seven children. Standard CBT components were implemented in 12
sessions (psychoeducation, cognitive restructuring, social skills training, exposure, and
relapse prevention). Children were instructed to use their newly developed skills outside
of treatment to ensure a transfer into everyday life.

Psychometric Measure
The SPAI-C (Beidel, Turner, Hamlin, & Morris, 2000) assesses behavioral characteristics
specific to SAD (26 items; e.g., “I am anxious when I meet new boys or girls”). Children
respond to each item using a 3-point Likert-type scale ranging from “never or hardly
ever” to “almost always or always.” Validity and reliability were confirmed in the original
sample (Beidel et al., 2000) and a German sample (Melfsen, Walitza, & Warnke, 2011).
Internal consistency and test–retest reliability after 4 weeks in the German sample was
excellent (Cronbach’s α = .92; rtt = .84).

Psychophysiological Measures
Electrodermal and cardiovascular measures including heart rate were assessed at 400 Hz
using the Varioport system (Becker Meditec, Karlsruhe, Germany). Data inspection and
artefact rejection were conducted offline using ANSLAB (Blechert, Peyk, Liedlgruber, &
Wilhelm, 2016). For the electrocardiogram, the cardiac interbeat interval (IBI), calculated
as the interval in milliseconds between successive R waves, was extracted. For illustrative
purposes the IBI was converted to heart rate (in beats per minute) for tables and figures
but all statistical analyses were based on IBI values (Quigley & Berntson, 1996). EDA, re‐
flecting electrodermal sympathetic activity (Boucsein, 2012), was assessed by placing two
electrodes on the middle phalanx of the middle and ring fingers of the left hand using
11-mm inner diameter Ag/AgCl electrodes filled with isotonic electrode paste (TD-245,
Med Associates, Inc., St. Albans, Vermont). As a parameter of EDA, skin conductance
level was used.

Interoceptive Accuracy (IAc)
We assessed IAc using the HCT. After a short training of about 10s, children were asked
to silently count their heartbeats during three instructed intervals (25, 35, 45s in a fixed
order), to indicate ‘zero’ if they had not perceived any, and not take their pulse or to use
any other strategies such as holding their breath (Eley et al., 2004). Subjective reports of
perceived heartbeats were checked for plausibility. For the first testing session, perceived
heart beats ranged between 10 and 86 (25s interval), 10 and 90 (35s interval), and 13
and 600 (45s interval). Based on the extreme value at the third interval, one child was
excluded from further analyses as it is possible that the child did not understand the
instructions correctly, leaving a range between 13 and 120 (45s interval). For the second

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testing session, perceived heart beats ranged between 7 and 70 (25s interval), 1 and 85
(35s interval), and 6 and 105 (45s interval).

To ensure comparability to an earlier study (Koch & Pollatos, 2014), IAc was calcula‐
ted using the formula:

IAcHCT =   13  k = 1
3

1 − no. of recorded heartbeatsk − no. of perceived heatbeatskno. of recorded heartbeatsk

Higher scores indicate higher IAc, with a maximum score of ‘1’ reflecting perfect IAc.
As physical symptom reporting is related to the tendency to report false alarms in a
somatosensory signal detection task (Brown et al., 2012), we calculated a simple IAc
score to distinguish over- from underreporting using the formula (Rost, Van Ryckeghem,
Schulz, Crombez, & Vögele, 2017):

IAcsimple =   13  k = 1
3 no. of perceived heartbeatsk − no. of recorded heartbeatsk

no. of recorded heartbeatsk

A positive score reflects over-reporting and a negative score reflects underreporting of
heartbeats.

Statistical Analysis
First, for objective measures, statistical outliers 2.5 SD above or below the mean were
excluded. Outliers were calculated separately for groups and time. To examine biases be‐
fore treatment, we conducted analyses of variance (ANOVAs) with repeated measures on
phase (baseline, stress, recovery), using group (SAD, HC) as between-subjects factor. For
objective physiology, EDA and heart rate were used as dependent variables in separate
ANOVAs. For subjective perception, rating (perception, worry) was further added as a
factor. We included first the heart rate and perspiration scales and then the blushing
and trembling scales as dependent variables in separate ANOVAs. Including objective
physiology as a covariate did not lead to any significances, ps > .05, and is therefore not
further reported. To consider that objective physiology and subjective perception (IS) and
worry (IE) might depend on each other, multiple correlation analyses were conducted for
both EDA and heart rate including subjective and objective measures. IAc scores (IAcHCT
and IAcsimple) from the first laboratory session were compared using an independent
sample t test with group (SAD, HC) as independent variable.

For treatment effects, we once again conducted ANOVAs with repeated measures
on session (pre, post) and phase (baseline, stress, recovery), using group (CBT, WLC)
as between-subjects factor. For objective physiology, EDA and heart rate were used as
dependent variables in separate ANOVAs. For subjective perception, perception and wor‐
ry of all physiology questionnaires (heart rate, perspiration, blushing, trembling) were

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analyzed as dependent variables in separate ANOVAs. Once again, multiple correlation
analyses were conducted for both EDA and heart rate including subjective and objective
measures. For the analysis of treatment effects on IAc scores, an ANOVA with repeated
measures on time (pre, post) was used based on treatment (CBT, WLC) as independent
variable. Further, a moderation analysis was conducted testing treatment as potential
moderator (CBT, WLC) between IAc pre (IAc_1) and post treatment (IAc_2) using the
PROCESS macro for SPSS (Hayes, 2013). Further exploratory analyses are reported in the
Supplementary Materials.

Significant main effects and interactions for all ANOVAs were further analyzed with
post hoc t tests for independent groups for the group comparisons and with t tests for de‐
pendent groups for the time comparisons (phase, session) if relevant for the hypotheses.
Cohen’s d effect sizes are reported for the post hoc tests.

R e s u l t s

Before Treatment: Objective Physiology Comparison of Children
With and Without SAD
We found higher heart rate (HR) during the stress as compared to the baseline and post
phases, Wilk’s λ = .351, F(2,94) = 87.07, p < .001, ηp2 = .649, but HR did not differ between
groups, F(1,95) = 0.87, p = .354. There was a significant interaction of Phase × Group,
Wilk’s λ = .870, F(2,94) = 87.07, p < .001, ηp2 = .130. Post hoc tests showed a significantly
higher HR in children in the SAD group during the baseline phase, t(95) = -2.30, p = .023,
d = 0.47, but no further group differences, ts < 1.33, ps > .187 (see Figure 3A). In the SAD
group, HR increased significantly from baseline to stress, t(53) = 7.12, p < .001, d = 0.41,
and decreased from stress to recovery, t(53) = -7.27, p < .001, d = 0.40. Similarly, in the HC
group, HR increased significantly from baseline to stress, t(42) = 11.31, p < .001, d = 0.67,
and decreased from stress to recovery, t(53) = -10.40, p < .001, d = 0.61. The significant
interaction between group and phase and the higher effect sizes for post-hoc tests in
the HC than the SAD group suggest a steeper increase and decrease in the HC group
compared to the SAD group.

EDA significantly increased over time, Wilk’s λ = .586, F(2,91) = 32.17, p < .001,
ηp2 = .414, and differed between groups, F(1,92) = 35.12, p < .001, ηp2 = .276. Furthermore,
we observed a significant Phase × Group interaction, Wilk’s λ = .750, F(2,91) = 15.14,
p < .001, ηp2 = .250. Post hoc tests showed that in the SAD group, EDA increased signif‐
icantly from baseline to stress, t(49) = 7.17, p < .001, d = 0.31, but did not decrease
from stress to recovery, t(49) = 1.30, p = .199, d = 0.02. Similarly, in the HC group, EDA
increased significantly from baseline to stress, t(43) = 4.45, p < .001, d = 0.23, but did not
decrease from stress to recovery, t(43) = 1.02, p = .311, d = 0.02 (see Figure 3B). Again,

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the significant interaction and the higher effect sizes imply a steeper increase in the HC
group compared to the SAD group.

Before Treatment: Subjective Physiology Perception Comparison
of Children With and Without SAD
For subjective perception of heart rate (IS), we found significant main effects of phase,
Wilk’s λ = .468, F(4,111) = 31.49, p < .001, ηp2 = .532, and group, Wilk’s λ = .861, F(2,113)
= 9.10, p < .001, ηp2 = .139, with a trend for a significant interaction of Phase × Group,
Wilk’s λ = .929, F(4,111) = 2.11, p = .084, ηp2 = .071. Groups differed in both perception
of and worry about heart rate in all phases (see Figure 4; ps < .05). The increase from
baseline to stress and the decrease from stress to recovery was significant in both groups,
ps < .001. Similar effects were found for subjective perception of perspiration, blushing,
and trembling (see Supplementary Materials).

Figure 3

Group Comparisons of (A) Heart Rate (in Beats per Minute, BPM) and (B) Electrodermal Activity During the First
Trier Social Stress Test for Children for Children With Social Anxiety Disorder (SAD) and Healthy Control (HC)
Children

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Figure 4

Subjective Perception of (A) and Worry (B) About Heart Rate After All Phases of the First Trier Social Stress Test
for Children

Note. For other parameters, see Supplementary Materials.

Before Treatment: Relations Between Objective and Subjective
Physiology
A multiple correlation analysis between objective heartrate and subjective perception of
and worry about heart rate did not reveal any significant correlation, ps > .084. Similarly,
no effects were found for EDA and subjective perception, ps > .105.

For the first laboratory session, neither the IAcHCT scores, t(96) = -1.29, p = .200, d =
0.26, nor the IAcsimple scores differed significantly between groups, t(98) = -1.48, p = .142,
d = 0.30.

After Treatment: Objective Physiology Comparison of Children
With SAD After Treatment Versus Waiting
Comparable to the first measurement occasion, HR was higher during stress than during
baseline and post phases, Wilk’s λ = .355, F(2,37) = 33.55, p < .001, ηp2 = .645. All other
effects remained nonsignificant, Fs < 2.77, ps < .103.

Again, EDA was higher during stress than during baseline and post phases, Wilk’s
λ = .388, F(2,37) = 29.15, p < .001, ηp2 = .612. All other effects remained nonsignificant, Fs <
3.91, ps < .057.

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After Treatment: Subjective Physiology Perception Comparison of
Children With SAD After Treatment Versus Waiting
For subjective perception of heart rate after treatment, the ANOVA showed a significant
main effect of phase, Wilk’s λ = .364, F(4,48) = 20.94, p < .001, ηp2 = .636, and a trend for a
significant effect of session, Wilk’s λ = .891, F(2,50) = 3.07, p = .055, ηp2 = .109. All other Fs
< 2.27, ps > .113 (see Figure 5).

Figure 5

Subjective Perception of and Worry About Heart Rate After All Phases of the First (A, B) and Second (C, D) Trier
Social Stress Test for Children (TSST-C), Comparing the Cognitive Behavioral Therapy (CBT) and Waitlist Control
(WLC) Groups

Note. For other parameters, see Supplementary Materials.

An analysis of the main effect of session for heart rate in both groups, using t tests for
paired samples, showed an overall decrease in the perception, t(56) = 2.03, p = .047, d

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= 0.28, and worry after the stress phase, t(56) = 2.22, p = .030, d = 0.30. All other ts <
1.33, ps > .191. So, heart rate perception and worry decreased in all children from TSST-C
1 to TSST-C 2. Similar effects were found for subjective perception of trembling (see
Supplementary Materials).

After Treatment: Relations Between Objective and Subjective
Physiology
A multiple correlation analysis at TSST-C 2 between objective HR and subjective percep‐
tion (IS) of and worry (IE) of HR did not reveal any significant correlation, ps > .077.
Similarly, no effects were found for EDA and subjective perception, ps > .229.

Regular IAcHCT did not change from pre- to post-measurement (main effect ‘session),
independent of treatment group (interaction treatment × session, Fs < 1.92, ps > .174).
Likewise, for IAcsimple, no significant effects appeared for treatment, session or session ×
treatment, Fs < 2.19, ps > .146.

Additionally, the moderation analysis showed an overall significant relation,
R 2 = .382, F(3,35) = 7.2, p < .001. There was a significant relation between IAc_1 and
IAc_2, while treatment was no significant moderator (Table 3).

Table 3

Prediction of IAc at Second Laboratory Session

Predictor b SE B t p

Constant -0.12 [-0.75, 0.51] 0.31 -0.38 .703
IAc_1 (standardized) 0.92 [0.03, 1.18] 0.44 2.09 .044
Treatment (CBT, WLC; standardized) 0.27 [-0.19, 0.74] 0.23 1.20 .237
IAc_1 × Treatment (CBT, WLC) -0.25 [-0.90, 0.40] 0.32 -0.79 .437

Note. IAc_1 = Interoceptive accuracy laboratory session 1, IAc_2 = Interoceptive accurarcy laboratory session 2.

D i s c u s s i o n
The study aimed to assess alterations in perception of (IS) and worry about (IE) physio‐
logical symptoms as well as IAc in childhood SAD. It further strived to examine possible
changes after CBT. Supporting our hypotheses at TSST-C 1, children with SAD showed
higher heart rate than children in the HC group during the baseline phase, and a lower
reactivity to stress. Further, EDA was heightened throughout the testing session. These
findings may indicate an autonomic hyperarousal and blunted stress reactivity in the
SAD group. Moreover, children in the SAD group reported heightened perception (IS) of
and increased worry (IE) about heart rate, perspiration, and trembling throughout the
TSST-C. There seems to be no biased perception for EDA. However, the pattern for the

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objective and subjective side in heart rate differed: Objectively, children in the HC group
showed a steep increase and decrease throughout the TSST-C 1. Subjectively however,
HC children’s perception and worry remained below that of SAD children. As blushing
and trembling were not controlled on objective parameters, this effect can only be con‐
firmed for heart rate and perspiration. Further, contrary to findings in adults (Domschke,
Stevens, Pfleiderer, & Gerlach, 2010), no differences in IAc were found between children
with SAD and HC children.

Findings after treatment were not in line with our hypotheses: Objective physiolog‐
ical parameters (heart rate, EDA) did not change. Interestingly, children in the CBT
group reported heightened perception of and increased worry about perspiration, and
trembling after the baseline phase at TSST-C 2 compared to children in the WLC group.
Additionally, both before and after treatment subjective and objective parameters did
not correlate. Further, as no differences appeared between children with SAD receiving
treatment vs. waiting, no effects of treatment on IAc can be assumed.

Before Treatment: Findings on Children With SAD Compared to
an HC Group
Objectively in line with earlier studies (cf., Asbrand et al., 2017), a tonic hyperarousal
was shown in children with SAD concerning EDA. However, in contrast to earlier studies
(Schmitz et al., 2012), this was mirrored by subjective perception. Part of the earlier
findings in high socially anxious children (Schmitz et al., 2012) still seems to be also
found in our sample: Concerning HR, children with SAD perceived an increase in their
physiological reaction that was not mirrored by the pattern of physiological reactivity.
Further, they worried more than children in the HC group that this physiological arousal
might be observable. Considering the point of (non)visibility of heart rate, children with
SAD might have more unrealistic worries that internal signals might be observable. As
our paradigm was slightly altered to Schmitz et al. (TSST-C instead of a speech task
with public vs. private sound of heart rate), our findings are not replication in a narrow
sense but show a robust effect in an established social stress test. However, mean scores
on symptom perception intensity as well as worry were rather low (< 5 on a scale of 0
to 10). The pattern of results demonstrates that worry is linked to several physiological
symptoms (but not all). Further, it may be that some physiological sensations are more
likely linked to SAD (e.g., blushing; Bögels, Rijsemus, & De Jong, 2002). These symptoms
are more consistently associated with worry, reflecting a more general tendency to wor‐
ry about SAD-related physiological symptoms instead of symptom-specific links between
perception of and worry about these symptoms. This might be related to visibility of
physiological symptoms. Finally, a lack of correlation between IAc, IS and IE provides
an interesting insight: It would be expected that a higher physiological arousal leads to
the perception of – and possibly worry about – these symptoms. However, our results
point to the independence of both sides. This might stem from the fact that children

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struggle more with IAc (Koch & Pollatos, 2014). The current study suggests that SAD
children do not show altered IAc, but report higher subjective heart rates (IS) and higher
worries about cardiac perceptions (IE). SAD in childhood may be reflected, therefore, by
a selective increase in the subjective tendency to be focused on heart rate increases and a
negative evaluation of these percepts, whereas the actual perception is unaffected.

After Treatment: Findings on a Treatment (CBT) Versus a WLC
Group
Children in the CBT group reported higher perception of and more worry about perspi‐
ration as well as more worry about trembling after the baseline phase of TSST-C 2. In
other words, children in the CBT group reported heightened perception of physiological
arousal and increased worry on some parameters after the baseline phase. Previous
findings from this sample could show that CBT was in general successful in reducing
the severity of SAD as measured by a blind interview after treatment (cf., Asbrand
et al., 2020). Further, some SAD-relevant rumination processes such as post-event pro‐
cessing changed for the better as negative thoughts after a social situation decreased
significantly after treatment (Asbrand, Schmitz, et al., 2019). Still, cortisol levels did not
change based on treatment; however, cortisol levels in the WLC group increased in the
second TSST-C (Asbrand, Heinrichs, et al., 2019). Overall, it would have been plausible
that physiological awareness and biased perception also change with treatment. Howev‐
er, instead of decreasing, children in the CBT group reported higher perception and
worry about several physiological parameters before entering the social stress situation.
It might be that children in the CBT group were sensitized to similar tasks as they
had experienced exposure sessions beforehand. Psychoeducation conveys a concept of
anxiety that includes cognitions, behavior, and physiological reactions. Often, this is the
first time children are confronted with such a concept. It might direct their attention
to these factors and, as such, support sensitization. Further, our treatment was rather
short (12 sessions), and recent research has argued that longer treatment is necessary in
SAD (e.g., Hudson et al., 2015). As the main treatment component, exposure, had to be
properly prepared (habituation rationale, first exposure in social skills sessions), only a
few sessions remained to experience in-vivo exposure. Thus, it is possible that treatment
was already successful in reducing overall symptoms (Asbrand, Heinrichs, et al., 2020),
but children were still in the process of handling high state anxiety. Additionally, our
treatment did not specifically target physiological symptoms and their interpretation.
This treatment component is more common in treatment of panic disorders (e.g., Clark
et al., 1999; Öst & Westling, 1995) but should be considered for SAD treatment as well,
given our results. However, interpretation of these findings of elevated perception and
worry in the CBT group should be evaluated cautiously as they were found only after
the baseline phase of the TSST-C and not after the stress phase. In addition, even if the

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pattern of results allows for interpretation of sensitization, the overall scores remain low
at posttreatment (mean scores < 4 on a scale of 0 to 10).

Finally, while comparison of single intervals of the HCT has shown high correlations
between these (e.g., Koch & Pollatos, 2014), our study is the first to show stability over
a longer period of time providing first evidence for IAc as a trait marker in children.
However, as we do not find differences in IAc between children with and without SAD in
our study, IAc may not play a key role for SAD in children. Possibly, a subsample of chil‐
dren with SAD suffering from panic-like symptoms (cf. Domschke, Stevens, Pfleiderer,
& Gerlach, 2010) in social situations might show both different IAc scores and changes
in IAc based on treatment. Future studies are warranted to investigate, which role other
occasion- or situation-specific factors, as well as error variance (Wittkamp et al., 2018),
contribute to IAc in in children.

Limitations and Conclusions
While the study has several strengths, such as a clinical sample and inclusion of treat‐
ment, several limitations apply. First, we assessed a variety of dependent variables based
on concerns to target physiological arousal broadly (Siess et al., 2014). Possibly, a lack
of effects might stem from lack of power. However, the current sample was relatively
large and could detect differences in treatment groups, even though they showed to be
contrary to expectations. Second, we did not assess all variables both subjectively and
objectively but provide subjective data only for blushing and trembling. Future studies
might target these variables to examine the objective basis for subjective perception. Pre‐
vious studies from adults, however, point to similar results for blushing, as this depends
mainly on social anxiety instead of objective blood flow (Drummond & Su, 2012). Third,
we refrained from using an experimental setup (cf., Gerlach et al., 2004; Schmitz et al.,
2012), instead opting for a standardized social stress task. Thus, taking note of these
earlier findings (Gerlach et al., 2004; Schmitz et al., 2012) on the importance of the per‐
ception of and worry about physiological arousal in social anxiety, we did not manipulate
visibility of physiological arousal but chose to measure subjective and objective arousal
in parallel during social stress. Finally, we did not include a correlation analysis between
a change in social anxiety symptoms and changes in perceptions of physiology as this
would not have been based on a solid theoretical background. However, future studies
could include this perspective to analyze a possible co-occurrence of change in anxiety
and perception of physiology.

In conclusion, our results indicate that SAD children show a selective enhancement
of subjective cardiac interoception, as proposed by cognitive models of SAD (Clark &
Wells, 1995), whereas behavioral indices of cardiac interoception and the perception
of EDA changes remain unaffected. CBT did not change this perception. Thus, further
inclusion of treatment components targeting this bias as currently proposed mainly by

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adult research (Hofmann & Otto, 2017; Naim, Kivity, Bar-Haim, & Huppert, 2018; Wong
et al., 2017) should be considered.

Funding: This research was supported by a grant from the DFG given to the last authors (HE 3342/4-2, TU 78/5-2).

Competing Interests: The authors have declared that no competing interests exist.

Acknowledgments: The authors have no support to report.

S u p p l e m e n t a r y  M a t e r i a l s
The supplementary materials include additional exploratory analyses on subjective perception of
perspiration, blushing and trembling before and after treatment (for access see Index of Supple‐
mentary Materials below):

Index of Supplementary Materials

Asbrand, J., Schulz, A., Heinrichs, N., & Tuschen-Caffier, B. (2020). Supplementary materials to
"Biased perception of physiological arousal in child social anxiety disorder before and after
cognitive behavioral treatment" [Additional exploratory analyses]. PsychOpen.
https://doi.org/10.23668/psycharchives.3086

R e f e r e n c e s

Allen, A. P., Kennedy, P. J., Dockray, S., Cryan, J. F., Dinan, T. G., & Clarke, G. (2017). The Trier
Social Stress test: Principles and practice. Neurobiology of Stress, 6, 113-126.
https://doi.org/10.1016/j.ynstr.2016.11.001

American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th
ed., text rev.). Washington, DC, USA: Author.

American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th
ed.). Washington, DC, USA: Author.

Antony, M. M., Brown, T. A., Craske, M. G., Barlow, D. H., Mitchell, W. B., & Meadows, E. A. (1995).
Accuracy of heartbeat perception in panic disorder, social phobia, and nonanxious subjects.
Journal of Anxiety Disorders, 9(5), 355-371. https://doi.org/10.1016/0887-6185(95)00017-I

Asbrand, J., Blechert, J., Nitschke, K., Tuschen-Caffier, B., & Schmitz, J. (2017). Aroused at home:
Basic autonomic regulation during orthostatic and physical activation is altered in children
with social anxiety disorder. Journal of Abnormal Child Psychology, 45(1), 143-155.
https://doi.org/10.1007/s10802-016-0147-7

Asbrand, J., Heinrichs, N., Nitschke, K., Wolf, O. T., Schmidtendorf, S., & Tuschen-Caffier, B. (2019).
Repeated stress leads to sensitization of the cortisol stress response in child social anxiety

Asbrand, Schulz, Heinrichs, & Tuschen-Caffier 21

Clinical Psychology in Europe
2020, Vol.2(2), Article e2691
https://doi.org/10.32872/cpe.v2i2.2691

https://doi.org/10.23668/psycharchives.3086
https://doi.org/10.1016/j.ynstr.2016.11.001
https://doi.org/10.1016/0887-6185(95)00017-I
https://doi.org/10.1007/s10802-016-0147-7
https://www.psychopen.eu/


disorder. Psychoneuroendocrinology, 109, Article 104352.
https://doi.org/10.1016/j.psyneuen.2019.06.003

Asbrand, J., Heinrichs, N., Schmidtendorf, S., Nitschke, K., & Tuschen-Caffier, B. (2020). Experience
versus report: Where are changes seen after exposure-based cognitive-behavioral therapy? A
randomized controlled group treatment of childhood social anxiety disorder. Child Psychiatry &
Human Development, 51, 427-441. https://doi.org/10.1007/s10578-019-00954-w

Asbrand, J., Schmitz, J., Krämer, M., Nitschke, K., Heinrichs, N., & Tuschen-Caffier, B. (2019). Effects
of group-based CBT on post-event processing in children with social anxiety disorder following
an experimental social stressor. Journal of Abnormal Child Psychology. Advance online
publication. https://doi.org/10.1007/s10802-019-00558-x

Bar-Haim, Y., Lamy, D., Pergamin, L., Bakermans-Kranenburg, M. J., & van Ijzendoorn, M. H.
(2007). Threat-related attentional bias in anxious and nonanxious individuals: A meta-analytic
study. Psychological Bulletin, 133, 1-24. https://doi.org/10.1037/0033-2909.133.1.1

Beidel, D. C., & Turner, S. M. (2007). Shy children, phobic adults: Nature and treatment of social
anxiety disorder. Washington, DC, USA: American Psychological Association.

Beidel, D. C., Turner, S. M., Hamlin, K., & Morris, T. L. (2000). The Social Phobia and Anxiety
Inventory for Children (SPAI-C): External and discriminative validity. Behavior Therapy, 31(1),
75-87. https://doi.org/10.1016/S0005-7894(00)80005-2

Blechert, J., Peyk, P., Liedlgruber, M., & Wilhelm, F. H. (2016). ANSLAB: Integrated multichannel
peripheral biosignal processing in psychophysiological science. Behavior Research Methods,
48(4), 1528-1545. https://doi.org/10.3758/s13428-015-0665-1

Bögels, S. M., Rijsemus, W., & De Jong, P. J. (2002). Self-focused attention and social anxiety: The
effects of experimentally heightened self-awareness on fear, blushing, cognitions, and social
skills. Cognitive Therapy and Research, 26(4), 461-472. https://doi.org/10.1023/A:1016275700203

Boucsein, W. (2012). Electrodermal activity. New York, NY, USA: Springer Science & Business
Media.

Brown, R. J., Skehan, D., Chapman, A., Perry, E. P., McKenzie, K. J., Lloyd, D. M., . . . Poliakoff, E.
(2012). Physical symptom reporting is associated with a tendency to experience somatosensory
distortion. Psychosomatic Medicine, 74(6), 648-655.
https://doi.org/10.1097/PSY.0b013e3182595358

Burstein, M., He, J. P., Kattan, G., Albano, A. M., Avenevoli, S., & Merikangas, K. R. (2011). Social
phobia and subtypes in the National Comorbidity Survey-Adolescent Supplement: Prevalence,
correlates, and comorbidity. Journal of the American Academy of Child and Adolescent
Psychiatry, 50(9), 870-880. https://doi.org/10.1016/j.jaac.2011.06.005

Buske-Kirschbaum, A., Jobst, S., Wustmans, A., Kirschbaum, C., Rauh, W., & Hellhammer, D. (1997).
Attenuated free cortisol response to psychosocial stress in children with atopic dermatitis.
Psychosomatic Medicine, 59(4), 419-426. https://doi.org/10.1097/00006842-199707000-00012

Clark, D. M., Salkovskis, P. M., Hackmann, A., Wells, A., Ludgate, J., & Gelder, M. (1999). Brief
cognitive therapy for panic disorder: A randomized controlled trial. Journal of Consulting and
Clinical Psychology, 67(4), 583-589. https://doi.org/10.1037/0022-006X.67.4.583

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https://doi.org/10.1007/s10578-019-00954-w
https://doi.org/10.1007/s10802-019-00558-x
https://doi.org/10.1037/0033-2909.133.1.1
https://doi.org/10.1016/S0005-7894(00)80005-2
https://doi.org/10.3758/s13428-015-0665-1
https://doi.org/10.1023/A:1016275700203
https://doi.org/10.1097/PSY.0b013e3182595358
https://doi.org/10.1016/j.jaac.2011.06.005
https://doi.org/10.1097/00006842-199707000-00012
https://doi.org/10.1037/0022-006X.67.4.583
https://www.psychopen.eu/


Clark, D. M., & Wells, A. (1995). A cognitive model of social phobia. In R. G. Heimberg, M.
Liebowitz, D. Hope, & F. Scheier (Eds.), Social phobia: Diagnosis, assessment, and treatment (pp.
69–93). New York, NY, USA: Guilford Press.

Domschke, K., Stevens, S., Pfleiderer, B., & Gerlach, A. L. (2010). Interoceptive sensitivity in anxiety
and anxiety disorders: An overview and integration of neurobiological findings. Clinical
Psychology Review, 30(1), 1-11. https://doi.org/10.1016/j.cpr.2009.08.008

Drummond, P. D., & Su, D. (2012). The relationship between blushing propensity, social anxiety and
facial blood flow during embarrassment. Cognition and Emotion, 26(3), 561-567.
https://doi.org/10.1080/02699931.2011.595775

Dudeney, J., Sharpe, L., & Hunt, C. (2015). Attentional bias towards threatening stimuli in children
with anxiety: A meta-analysis. Clinical Psychology Review, 40, 66-75.
https://doi.org/10.1016/j.cpr.2015.05.007

Eley, T. C., Gregory, A. M., Clark, D. M., & Ehlers, A. (2007). Feeling anxious: A twin study of panic/
somatic ratings, anxiety sensitivity and heartbeat perception in children. Journal of Child
Psychology and Psychiatry, and Allied Disciplines, 48(12), 1184-1191.
https://doi.org/10.1111/j.1469-7610.2007.01838.x

Eley, T. C., Stirling, L., Ehlers, A., Gregory, A. M., & Clark, D. M. (2004). Heart-beat perception,
panic/somatic symptoms and anxiety sensitivity in children. Behaviour Research and Therapy,
42(4), 439-448. https://doi.org/10.1016/S0005-7967(03)00152-9

Garfinkel, S. N., Seth, A. K., Barrett, A. B., Suzuki, K., & Critchley, H. D. (2015). Knowing your own
heart: Distinguishing interoceptive accuracy from interoceptive awareness. Biological
Psychology, 104, 65-74. https://doi.org/10.1016/j.biopsycho.2014.11.004

Georgiou, E., Matthias, E., Kobel, S., Kettner, S., Dreyhaupt, J., Steinacker, J. M., & Pollatos, O.
(2015). Interaction of physical activity and interoception in children. Frontiers in Psychology, 6,
Article 502. https://doi.org/10.3389/fpsyg.2015.00502

Gerlach, A. L., Mourlane, D., & Rist, F. (2004). Public and private heart rate feedback in social
phobia: A manipulation of anxiety visibility. Cognitive Behaviour Therapy, 33(1), 36-45.
https://doi.org/10.1080/16506070310014682

Hayes, A. F. (2013). Introduction to mediation, moderation, and conditional process analysis: A
regression‐based approach. New York, NY, USA: The Guilford Press.

Hofmann, S. G., & Otto, M. W. (2017). Cognitive behavioral therapy for social anxiety disorder:
Evidence-based and disorder specific treatment techniques. New York, NY, USA: Routledge.

Hudson, J. L., Rapee, R. M., Lyneham, H. J., McLellan, L. F., Wuthrich, V. M., & Schniering, C. A.
(2015). Comparing outcomes for children with different anxiety disorders following cognitive
behavioural therapy. Behaviour Research and Therapy, 72, 30-37.
https://doi.org/10.1016/j.brat.2015.06.007

Koch, A., & Pollatos, O. (2014). Cardiac sensitivity in children: Sex differences and its relationship
to parameters of emotional processing. Psychophysiology, 51, 932-941.
https://doi.org/10.1111/psyp.12233

Asbrand, Schulz, Heinrichs, & Tuschen-Caffier 23

Clinical Psychology in Europe
2020, Vol.2(2), Article e2691
https://doi.org/10.32872/cpe.v2i2.2691

https://doi.org/10.1016/j.cpr.2009.08.008
https://doi.org/10.1080/02699931.2011.595775
https://doi.org/10.1016/j.cpr.2015.05.007
https://doi.org/10.1111/j.1469-7610.2007.01838.x
https://doi.org/10.1016/S0005-7967(03)00152-9
https://doi.org/10.1016/j.biopsycho.2014.11.004
https://doi.org/10.3389/fpsyg.2015.00502
https://doi.org/10.1080/16506070310014682
https://doi.org/10.1016/j.brat.2015.06.007
https://doi.org/10.1111/psyp.12233
https://www.psychopen.eu/


Krämer, M., Seefeldt, W. L., Heinrichs, N., Tuschen-Caffier, B., Schmitz, J., Wolf, O. T., & Blechert, J.
(2012). Subjective, autonomic, and endocrine reactivity during social stress in children with
social phobia. Journal of Abnormal Child Psychology, 40(1), 95-104.
https://doi.org/10.1007/s10802-011-9548-9

Leigh, E., & Clark, D. M. (2018). Understanding social anxiety disorder in adolescents and
improving treatment outcomes: Applying the cognitive model of Clark and Wells (1995).
Clinical Child and Family Psychology Review, 21(3), 388-414.
https://doi.org/10.1007/s10567-018-0258-5

Mauss, I. B., Wilhelm, F., & Gross, J. J. (2004). Is there less to social anxiety than meets the eye?
Emotion experience, expression, and bodily responding. Cognition and Emotion, 18(5), 631-642.
https://doi.org/10.1080/02699930341000112

Melfsen, S., Walitza, S., & Warnke, A. (2011). Psychometrische Eigenschaften und Normierung des
Sozialphobie und -angstinventars für Kinder (SPAIK) an einer klinischen Stichprobe. Zeitschrift
fur Kinder- und Jugendpsychiatrie und Psychotherapie, 39(6), 399-407.
https://doi.org/10.1024/1422-4917/a000138

Miers, A. C., Blöte, A. W., Sumter, S. R., Kallen, V. L., & Westenberg, P. M. (2011). Subjective and
objective arousal correspondence and the role of self-monitoring processes in high and low
socially anxious youth. Journal of Experimental Psychopathology, 2(4), 531-550.
https://doi.org/10.5127/jep.019411

Naim, R., Kivity, Y., Bar-Haim, Y., & Huppert, J. D. (2018). Attention and interpretation bias
modification treatment for social anxiety disorder: A randomized clinical trial of efficacy and
synergy. Journal of Behavior Therapy and Experimental Psychiatry, 59, 19-30.
https://doi.org/10.1016/j.jbtep.2017.10.006

Öst, L. G., & Westling, B. E. (1995). Applied relaxation vs cognitive behavior therapy in the
treatment of panic disorder. Behaviour Research and Therapy, 33(2), 145-158.
https://doi.org/10.1016/0005-7967(94)E0026-F

Pollatos, O., & Herbert, B. M. (2018). Interoception: Definitions, dimensions, neural substrates. In G.
Hauke & A. Kritikos (Eds.), Embodiment in psychotherapy (pp. 15-27). Cham, Switzerland:
Springer.

Pollatos, O., Traut-Mattausch, E., Schroeder, H., & Schandry, R. (2007). Interoceptive awareness
mediates the relationship between anxiety and the intensity of unpleasant feelings. Journal of
Anxiety Disorders, 21(7), 931-943. https://doi.org/10.1016/j.janxdis.2006.12.004

Quigley, K. S., & Berntson, G. G. (1996). Autonomic interactions and chronotropic control of the
heart: Heart period versus heart rate. Psychophysiology, 33, 605-611.
https://doi.org/10.1111/j.1469-8986.1996.tb02438.x

Rao, P. A., Beidel, D. C., Turner, S. M., Ammerman, R. T., Crosby, L. E., & Sallee, F. R. (2007). Social
anxiety disorder in childhood and adolescence: Descriptive psychopathology. Behaviour
Research and Therapy, 45(6), 1181-1191. https://doi.org/10.1016/j.brat.2006.07.015

Rapee, R. M., & Heimberg, R. G. (1997). A cognitive-behavioral model of anxiety in social phobia.
Behaviour Research and Therapy, 35(8), 741-756. https://doi.org/10.1016/S0005-7967(97)00022-3

Biased Perception of Physiology in Child SAD 24

Clinical Psychology in Europe
2020, Vol.2(2), Article e2691
https://doi.org/10.32872/cpe.v2i2.2691

https://doi.org/10.1007/s10802-011-9548-9
https://doi.org/10.1007/s10567-018-0258-5
https://doi.org/10.1080/02699930341000112
https://doi.org/10.1024/1422-4917/a000138
https://doi.org/10.5127/jep.019411
https://doi.org/10.1016/j.jbtep.2017.10.006
https://doi.org/10.1016/0005-7967(94)E0026-F
https://doi.org/10.1016/j.janxdis.2006.12.004
https://doi.org/10.1111/j.1469-8986.1996.tb02438.x
https://doi.org/10.1016/j.brat.2006.07.015
https://doi.org/10.1016/S0005-7967(97)00022-3
https://www.psychopen.eu/


Rost, S., Van Ryckeghem, D. M. L., Schulz, A., Crombez, G., & Vögele, C. (2017). Generalized
hypervigilance in fibromyalgia: Normal interoceptive accuracy, but reduced self-regulatory
capacity. Journal of Psychosomatic Research, 93, 48-54.
https://doi.org/10.1016/j.jpsychores.2016.12.003

Schandry, R. (1981). Heart beat perception and emotional experience. Psychophysiology, 18(4),
483-488. https://doi.org/10.1111/j.1469-8986.1981.tb02486.x

Schmitz, J., Blechert, J., Krämer, M., Asbrand, J., & Tuschen-Caffier, B. (2012). Biased perception and
interpretation of bodily anxiety symptoms in childhood social anxiety. Journal of Clinical Child
and Adolescent Psychology, 41(1), 92-102. https://doi.org/10.1080/15374416.2012.632349

Schmitz, J., Tuschen-Caffier, B., Wilhelm, F. H., & Blechert, J. (2013). Taking a closer look:
Autonomic dysregulation in socially anxious children. European Child & Adolescent Psychiatry,
22(10), 631-640. https://doi.org/10.1007/s00787-013-0405-y

Schneider, S., Unnewehr, S., & Margraf, J. (2008). Kinder-DIPS: Diagnostisches Interview bei
psychischen Störungen im Kindes- und Jugendalter (2nd ed.). Göttingen, Germany: Hogrefe.

Siess, J., Blechert, J., & Schmitz, J. (2014). Psychophysiological arousal and biased perception of
bodily anxiety symptoms in socially anxious children and adolescents: A systematic review.
European Child & Adolescent Psychiatry, 23(3), 127-142.
https://doi.org/10.1007/s00787-013-0443-5

Wittkamp, M. F., Bertsch, K., Vögele, C., & Schulz, A. (2018). A latent state-trait analysis of
interoceptive accuracy. Psychophysiology, 55(6), Article e13055.
https://doi.org/10.1111/psyp.13055

Wong, Q. J., Gregory, B., McLellan, L. F., Kangas, M., Abbott, M. J., Carpenter, L., . . . Rapee, R. M.
(2017). Anticipatory processing, maladaptive attentional focus, and postevent processing for
interactional and performance situations: treatment response and relationships with symptom
change for individuals with social anxiety disorder. Behavior Therapy, 48(5), 651-663.
https://doi.org/10.1016/j.beth.2017.03.004

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Association of Clinical Psychology and Psychological Treatment (EACLIPT).

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https://doi.org/10.1016/j.jpsychores.2016.12.003
https://doi.org/10.1111/j.1469-8986.1981.tb02486.x
https://doi.org/10.1080/15374416.2012.632349
https://doi.org/10.1007/s00787-013-0405-y
https://doi.org/10.1007/s00787-013-0443-5
https://doi.org/10.1111/psyp.13055
https://doi.org/10.1016/j.beth.2017.03.004
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	Biased Perception of Physiology in Child SAD
	(Introduction)
	The Current Study

	Method
	Trial Design
	Participants
	Procedure
	Treatment
	Psychometric Measure
	Psychophysiological Measures
	Interoceptive Accuracy (IAc)
	Statistical Analysis

	Results
	Before Treatment: Objective Physiology Comparison of Children With and Without SAD
	Before Treatment: Subjective Physiology Perception Comparison of Children With and Without SAD
	Before Treatment: Relations Between Objective and Subjective Physiology
	After Treatment: Objective Physiology Comparison of Children With SAD After Treatment Versus Waiting
	After Treatment: Subjective Physiology Perception Comparison of Children With SAD After Treatment Versus Waiting
	After Treatment: Relations Between Objective and Subjective Physiology

	Discussion
	Before Treatment: Findings on Children With SAD Compared to an HC Group
	After Treatment: Findings on a Treatment (CBT) Versus a WLC Group
	Limitations and Conclusions

	Notes
	(Additional Information)
	Funding
	Competing Interests
	Acknowledgments

	Supplementary Materials
	References