ORIGINAL RESEARCH ARTICLE
published: 04 November 2014
doi: 10.3389/fpsyg.2014.01262
Borderline personality disorder is associated with lower
confidence in perception of emotional body movements
Morten Kaletsch1,2 *, Britta Krüger 3,4 , Sebastian Pilgramm3,4 , Rudolf Stark 4 , Stefanie Lis 5 ,
Bernd Gallhofer 1 , Karen Zentgraf 4,6 , Jörn Munzert 3 and Gebhard Sammer 1,2
1
Cognitive Neuroscience Group, Center for Psychiatry and Psychotherapy, Justus Liebig University, Giessen, Germany
Department of Psychology, Justus Liebig University Giessen, Giessen, Germany
3
Institute for Sports Science, Justus Liebig University Giessen, Giessen, Germany
4
Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany
5
Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany
6
Institute for Sports Science, University of Munster, Münster, Germany
2
Edited by:
Marina A. Pavlova, Eberhard Karls
University of Tübingen, Germany
Reviewed by:
Daniel S. Quintana, University of
Oslo, Norway
Mariska Esther Kret, University of
Amsterdam, Netherlands
*Correspondence:
Morten Kaletsch, Cognitive
Neuroscience Group, Center for
Psychiatry and Psychotherapy, Justus
Liebig University, Am Steg 28, 35392
Giessen, Germany
e-mail: morten.kaletsch@psychol.
uni-giessen.de
Much recent research has shown that personality disorders are associated with an altered
emotion perception. Whereas most of this research was conducted with stimuli such as
faces, the present study examined possible differences in the perception of emotions
expressed via body language and body movements. 30 patients with borderline personality
disorder (BPD) and 30 non-patients observed video scenes of emotional human interactions
conveyed by point–light displays, rated the depicted valence, and judged their confidence
in this rating. Patients with BPD showed no altered emotion perception (i.e., no biased
perception in either a negative or a positive direction). They did not perceive and evaluate
depicted emotions as being more extreme than healthy controls. However, patients with
BPD showed less confidence in their perception of depicted emotions, especially when
these were difficult to identify. The findings extend insights on altered emotion perception
in persons with BPD to include the field of body movements.
Keywords: borderline personality disorder, emotion perception, point–light displays, social cognition, embodiment,
body movements, kinematics
INTRODUCTION
Borderline personality disorder (BPD) is a psychological condition characterized by interpersonal dysfunction and problems, unstable relationships, emotional dysregulation, suicidal
behavior, impulsive aggressions such as verbal outbursts, and
rapid switches between idealizing and devaluing relationships
[American Psychiatric Association (APA), 2000; Lieb et al., 2004].
These dysfunctional thoughts and behaviors may bring patients
into conflict with other people, may lead them to experience rejection and abandonment more often than non-patients (Stepp et al.,
2009; Renneberg et al., 2011; Lis and Bohus, 2013).
One central feature of the interactional problems of BPD
patients is their altered emotion perception. Despite a broad body
of studies, findings on this topic are not always consistent. On the
one hand, people with BPD are assumed to have negative evaluation styles and beliefs about themselves, others, and the world;
and that they make negatively biased assessments, are overly sensitive, and pay more attention to negative stimuli. Especially when
exposed to neutral or ambiguous stimuli, patients—compared to
healthy controls (HCs)—evaluate others as being more negative,
aggressive, or extreme [American Psychiatric Association (APA),
2000; Arntz and Veen, 2001; Sieswerda et al., 2005; Barnow et al.,
2009; Domes et al., 2009; Baer et al., 2012; Daros et al., 2014]. For
example, people with BPD have been shown to perceive neutral or
ambiguous pictures or videos of faces or whole body displays in a
negatively distorted way (Dyck et al., 2009; Baer et al., 2012), pay
more attention to emotions such as anger but are equally sensitive
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when recognizing emotions (Domes et al., 2008; Robin et al., 2012;
Hagenhoff et al., 2013).
On the other hand and in contrast to findings on deficient
emotion recognition, the literature also reveals results where no
differences occur and even evidence of better performance of BPD
patients on emotion recognition processes (Lynch et al., 2006;
Minzenberg et al., 2006; Domes et al., 2008; Merkl et al., 2010;
Franzen et al., 2011; Unoka et al., 2011; Robin et al., 2012; Schilling
et al., 2012; Schulze et al., 2013; Sieswerda et al., 2013).
In addition to research on emotion evaluation biases within this
patient group, several studies have shown that people with BPD
recognize emotions presented as pictures or videos of faces or
body displays less accurately than controls, and that this accuracy
decreases with increasing affect intensity. They recognize negative
emotions, particularly anger, disgust, and sadness, less well than
controls; show deficits in recognizing neutral facial expressions;
and perceive and evaluate the personality traits of film characters
as being more extreme (Levine et al., 1997; Veen and Arntz, 2000;
Bland et al., 2004; Domes et al., 2009; Dyck et al., 2009; Merkl et al.,
2010; Unoka et al., 2011; Arntz and ten Haaf, 2012; Robin et al.,
2012; Daros et al., 2013).
In patients with BPD, clinical observations and practice let us
presume a lack of confidence regarding recognizing emotion of
other people. This often refers to emotions, which are expressed
moderately without extreme intensity, facial expressions or gestures. Since patients often had been exposed to the experience of
violence and strong negative emotions during their life (Zanarini,
November 2014 | Volume 5 | Article 1262 | 1
Kaletsch et al.
2000; Lieb et al., 2004; Barnow et al., 2005) one may hypothesize
that this way of expressing emotions is more familiar to patients
than a quieter and more moderate way of expressing emotions.
Literature on confidence in emotion perception among patients
is not numerous. Schilling et al. (2012) showed that patients were
significantly more confident in their decision while performing a
theory of mind paradigm wherein they should identify the emotions of facial expressions. Also, patients were more confident
compared to controls in a false-memory paradigm in which participants were asked to recognize details from scenes they had
watched earlier (Schilling et al., 2013). Due to the small number
of reports in this research area, we were interested in whether and
to what extend patients would differ in their feelings of confidence
during emotion perception.
It has to be noted that most research on emotion perception in patients with BPD has focused on emotions expressed
via basic facial expression and prosody. Until now, few studies
have used whole body displays or entire movie scenes or film
clips showing one person or even two people in an interaction
(Domes et al., 2009). However, in everyday interactions, people
do not present static facial expressions but rather a complex set
of expressions, gestures, and body language. When people perceive their interaction partners, they use multiple modalities to
infer their emotional states. Thus, focusing on facial expressions
probably neglects an important human system for expressing
emotion: the human body and its movements. Human body
movement can also convey emotions, and observers can infer the
emotional state of an individual or of interacting persons solely
from their movements, even when they are far away and their
faces of are not clearly visible (de Gelder, 2006). Furthermore,
body movements do not only provide information on a possible unspecific threat as facial expressions do. Body movements
or postures of anger implicate a more specific physical threat,
they bind attention and also they also give a direct cue regarding an adequate behavioral response (Johansson, 1973; Sevdalis
and Keller, 2011; Atkinson et al., 2012; Ennis and Egges, 2012;
Lorey et al., 2012; Barliya et al., 2013; Kret and de Gelder, 2013;
Gelder and Hortensius, 2014). Moreover, social interaction and
social context seems to facilitate the emotion recognition process, so that observing two people interacting rather than just one
person alone also enhances the validation of perceived emotion
and the perception of emotions and confidence in this perception.
This emphasizes the relevance of social context for emotion perception (Clarke et al., 2005; Kret and de Gelder, 2010; Lorey et al.,
2012).
To investigate the perception of emotional body movements
while completely excluding facial information and other distracting variables, this study exploits the advantages of point–light
displays (PLDs). These are recordings of the kinematics of a
few dots placed on a model’s body. This technique has already
been used to detect gender differences in the perception of
emotional body language (Alaerts et al., 2011; Sokolov et al.,
2011), or for the investigation of differences in emotion perception of various patients groups with somatic and psychological
impairments (Pavlova, 2012). Henry et al. (2012), for example, found an impaired processing of socially relevant motions
and emotions among patients with dementia. Nackaerts et al.
Frontiers in Psychology | Emotion Science
Emotion perception in point–light displays
(2012) showed a lower accuracy among persons with autism
spectrum disorder whilst recognizing a person’s movements or
emotional state and Kaletsch et al. (2014) discovered that patients
with major depressive disorder rated emotional body movements
more negatively and with higher confidence compared to HCs.
Also for patients with schizophrenia deficits in emotion perception of biological and emotional body movements and facial
expressions are discussed (Tomlinson et al., 2006; Spencer et al.,
2013).
The advantage of using such highly simplified representations
is that they provide only kinematic movement information. This
ensures that the perception process is not influenced by confounding variables in the stimulus material such as attractiveness,
sympathy, and other cultural aspects found in the complex and
natural stimuli of faces or whole-body presentations (Hoffmann
et al., 2010).
Against this background, we examined the possible differences
between patients with BPD and HC. More precisely, we hypothesized that patients with BPD would (a) rate the emotional valence
of the depicted interactions more negatively compared to HC, (b)
differ in the experienced intensity of depicted emotions, especially
when emotional scenes are negative, and (c) differ from controls in
how confident they are about their ratings of depicted emotions.
MATERIALS AND METHODS
ETHICAL STATEMENT
The study was approved by the local ethics committee (local ethics
commission, Department of Psychology and Sports Science, and
local ethics committee of the Department of Medicine, Justus
Liebig University Giessen). All participants gave their informed
written consent to participate in the study in accordance with the
Declaration of Helsinki.
PARTICIPANTS
The total sample consisted of 60 adults: 30 patients receiving
treatment at the Center of Psychiatry and Psychotherapy at the
university hospital of the Justus Liebig University Giessen and 30
HC (see Table 1 for descriptive statistics).
The 30 patients (27 female, mean age = 30.4 years, SD = 10.4,
range = 18–68) were diagnosed with BPD according to DSMIV criteria. Of these patients, 13 were taking antidepressants; 3
antipsychotics; 10 a combination of drugs (antidepressant and/or
antipsychotic and/or sedative and/or mood stabilizer); and four
patients were taking no medication at the time of the study.
Five patients met the criteria for another current mental
disorder: major depression (n = 1), eating disorder (n = 3), posttraumatic stress disorder (n = 1). Eight met the criteria for more
than one other mental disorder: major depression, posttraumatic
stress disorder, and eating disorder (n = 1); major depression
and posttraumatic stress disorder (n = 1); major depression and
anxiety disorder (n = 1); major depression and attention deficit
disorder with hyperactivity (n = 1); posttraumatic stress disorder and eating disorder (n = 3); and anxiety disorder and eating
disorder (n = 1).
Diagnoses were conducted by experienced psychiatrists and
clinical psychologists. Patients with present or previous neurological disease or trauma, alcohol or drug dependence, acute or chronic
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Kaletsch et al.
Emotion perception in point–light displays
Table 1 | Results of descriptive statistics and t -test for age, questionnaire results, rating of valence, intensity of rating, and confidence in rating
by group.
Healthy controls
N
M
Patients
SD
N
M
SD
t
df
Age
30
34.3
10.6
30
30.43
10.45
Beck Depression Inventory, BDI-II
30
4.27
3.05
30
30.93
12.22
−11.59***
1.42
58
58
Toronto Alexithymia Scale, TAS-26
30
2.12
0.39
29
3.23
0.59
−8.43***
57
Positive and Negative Affect schedule, PANAS
30
3.18
0.64
29
2.18
0.87
5.00***
57
Positive and Negative Affect schedule, PANAS
30
1.18
0.28
28
2.17
1.04
5.01***
56
Borderline Symptom list, BSL
–
–
–
23
0.06
0.06
–
–
Rating of valence
30
4.04
0.27
30
3.91
0.39
1.48
58
Intensity of rating
30
5.55
0.29
30
5.59
0.32
−0.50
Confidence in rating
30
9.29
0.98
30
8.52
0.95
3.03*
58
58
*p < 0.05, ***p < 0.001.
psychotic disorders, bipolar disorders, as well as other medical
conditions that could influence cognitive functioning were not
included in the study.
The 30 age-matched healthy adults (27 female, mean
age = 34.3 years, SD = 10.6, range = 20–51) were recruited as a HC
group. Controls were derived from a population of 96 healthy subjects, who were recruited as part of the project across different age
groups and levels of education. Age difference between controls
and patients was similar (Table 1). The same HC group was used
for prior studies (Lorey et al., 2012; Kaletsch et al., 2014). The same
exclusion criteria were applied as for patients. In addition, HC were
excluded if they had any history of psychiatric or neurological disorders, any history or current use of psychoactive medication, or
a score higher than 13 on the Beck Depression Inventory, BDI-II
(Hautzinger et al., 2009). The following questionnaires in their
German versions were administered to better describe our sample: Beck-Depression Inventory (BDI-II; Hautzinger et al., 2009),
Toronto Alexithymia Scale (TAS-26; Kupfer et al., 2001), Positive and Negative Affect Schedule (PANAS; Watson et al., 1988),
and only for patients with BPD the Borderline Symptom List
(BSL; Bohus et al., 2001). For all questionnaires (except Borderline
Symptom List) the scores differed statistically significant between
groups (Table 1). Within each group, questionnaire results were
not correlated to any of the dependent variables – and thus gave no
further insight into how they are related or might have influenced
the results.
PRODUCING PLDs
The procedure for creating and validating stimuli was the same
as that in Lorey et al. (2012; Kaletsch et al., 2014) where it is also
described in more detail. Seven pairs of actors provided the movements for PLDs. Each pair was asked to perform an interaction
portraying one of the following four emotions: anger, sadness,
joy, and love. We pooled interactions with anger and sadness into
the category “negative” and interactions with love and joy into the
category “positive.” Prior to acting, we gave both actors a script
instructing them to perform the same emotion together in order
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to produce a behavioral pattern that was as symmetrical as possible. We asked them to act out the emotion immediately, but
gave them complete freedom to express the emotions in whatever way they liked—for example, by overt symbolic gestures.
We produced at least four clips of each pair and each emotional
scene. In addition, for each of the dyadic PLDs (scene with two
actors: dyad), we created a monadic PLD version consisting of the
dots of one of the two individuals alone (scene with one actor:
monad). Apart from this, these monadic scenes still displayed
the same emotion with the same movements. This resulted in a
corpus of 96 recordings with eight recordings for each category
(monad vs. dyad × positive vs. negative × 3 difficulty levels, see
below).
We attached 13 reflective markers to defined anatomical landmarks on the upper body (including the shoulders, the elbow
joints, the wrists, and the forehead) and the lower body (including
the hips, the knee joints, and the ankles) of each actor (Figure 1).
Then we recorded all interactions with a 12-camera VICON MX
system (Oxford Metrics, Oxford, England) operating at 100 Hz.
After capturing, we postprocessed the data with Nexus 1.5.2 (Vicon
Motion Systems, Oxford, England) in order to calculate 3-D coordinates of the markers. We created the video files in a two-step
process using Matlab software (MathWorks, Natick, MA, USA).
First, for each point in time, we plotted the 3-D coordinates of
the 13 markers as white spheres on a black background. Then, we
rendered the frames of the captured scenes as audio–video interleaved (avi) movie files at a frame rate of 25 Hz. For each scene,
we created 4-s video files viewed from the front. In all presented
PLDs, the dots appeared white against a black background at an
approximate viewing distance of 50 cm (Figure 1).
STIMULI: VALIDATION AND DETERMINATION OF DIFFICULTY OF EACH
EMOTIONAL SCENE
Prior to the experiment, we determined an index of item difficulty
for all recorded PLDs in order to separate the recordings into
three classes (easy, medium, and difficult to recognize). We asked
30 participants who did not participate in the present study to
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Kaletsch et al.
Emotion perception in point–light displays
7-point scale ranging from 1 (negative) to 7 (positive) with 4 marking the neutral (neither positive nor negative emotion) center of
the scale. The cursor was placed in the middle of the scale at
the beginning of each rating. To control for a rating bias caused
by the orientation of the scale, the scale was flipped for one-half
of the participants. After each valence rating, participants were
asked to report how confident they were about their rating on an
11-point on-screen scale ranging from 1 (0% confidence) to 11
(100% confidence).
DATA ANALYSIS AND STATISTICS
FIGURE 1 | Preparation of stimuli. Point–light displays were created by
attaching 13 reflective markers to an actor’s head, shoulders, elbows,
wrists, hips, knees, and ankles. They were then tracked using a Vicon
motion-capture system. (A) Examples of dyadic and monadic point–light
displays. (B) Temporal structure of the paradigm. Reprinted from Kaletsch
et al. (2014).
evaluate the negativity or the positivity of the emotions displayed
in the videos in a forced-choice paradigm. We created the three
categories of item difficulty by calculating the percentage of people
who agreed on the depicted emotion of the video scene. Thus, easy
videos were defined by a consensus of 91–100%; medium videos,
by a consensus of 71–90%; and difficult videos, by a consensus of
50–70%. For further description of the procedure see Lorey et al.
(2012) and Kaletsch et al. (2014).
PROCEDURE
Prior to the main experiment all participants completed questionnaires. Either before or after the actual experiment a control
session was conducted, to ensure participants’ ability to recognize
movements from PLDs. We presented participants with control
stimuli depicting sports movements such as juggling and basketball, and asked them to give a brief definition of each movement as
quickly as possible. One-half of the participants started with the
experiment and the other half with the control session in order to
control for sequence effects.
The experiment consisted of the aforementioned 96 video trials which were presented in a randomized order. Each single trial
started with the instruction (3 s), followed by a gaze fixation phase
(1 s), and the respective video sequence (4 s). After watching
the video, participants were asked to assess the depicted emotional valence of the videos. Ratings were done using an on-screen
Frontiers in Psychology | Emotion Science
For statistical data analysis all valence ratings were recorded. Scores
of 1 to 3 always reflected a negative rating and scores of 5 to 7 a positive rating. For the statistical analysis, we calculated mean scores
for each rating and each experimental condition. We calculated
mean scores for the perceived valence by summing up all responses
on the 7-point scales and dividing the sum by the number of videos
displayed. We operationalized intensity of ratings as the extent to
which participants gave ratings that were closer to the endpoints
on the 7-point scale, under the assumption that intensity would
be coded higher when the rating was closer to the ends of the scale.
To create mean scores of intensity of ratings, we reversed all scores
on the 7-point scale for ratings of perceived valence of negative
videos (1 into 7, 2 into 6, etc.), to obtain scores comparable to
those for positive videos. In other words, for both kinds of videos
(negative and positive), higher scores indicated a higher intensity
of ratings. We calculated mean scores on confidence by summing
all responses from the 11-point scale and dividing the sum by the
number of displayed videos.
To investigate differences between patients with BPD and HC in
perceiving emotional valence, the perceived intensity of emotions,
and confidence in emotion perception, repeated measurement
ANOVAs were computed for perceived valence, intensity, and
confidence. Main factors were the depicted emotion (positive vs.
negative), the social context (monads vs. dyads), the difficulty
of videos (easy, medium, difficult), and group as a categorical
between-group factor. Means and standard deviations are displayed in Table 1, results of repeated measurement ANOVAs could
be found in Table 2.
All statistics were calculated using SPSS software (Versions 19
and 20). An alpha level of 0.05 was used for all statistical tests.
Since the approach in this work is innovatory in the field of emotion perception in patients with BPD, we will also report results
with a significance level of 0.05–0.10. Thus, we ensure to give a
more informative overview what might be important for future
research.
RESULTS
CONTROL DATA
Control session: biological motion recognition test
Participants were able to identify each of the actions reliably and
far above chance level. On average, 93.07% (range: 67–100%) of
identifications were correct.
Influence of group on rated valence (negative or positive)
There was no significant effect of group (BPD vs. HC) on the
rating of perceived emotional valence, F(1,58) = 2.19, p = 0.144.
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Kaletsch et al.
Emotion perception in point–light displays
Table 2 | Statistical data of depicted emotion × social context × difficulty repeated-measures ANOVA for rating of valence, intensity of rating,
and confidence in rating.
η2
df
F
p
Group (between-group factor)
1, 58
2.19
0.04
0.14
Depicted emotion
1, 58
1792.99
0.96
0.000*
Rating of emotional valence
Depicted emotion × group
1, 58
0.25
0.00
0.61
Social context
1, 58
7.92
0.12
0.007*
Social context × group
1, 58
3.56
0.06
0.06
Difficulty
2, 116
10.09
0.15
0.000*
Difficulty × group
2, 116
0.19
0.00
0.82
Depicted emotion × social Context
1, 58
514.41
0.89
0.000*
Depicted emotion × social context × group
1, 58
1.478
0.03
0.23
Depicted emotion × difficulty
2, 116
258.92
0.82
0.000*
Depicted emotion × difficulty × group
2, 116
0.02
0.00
0.98
Social context × difficulty
2, 116
17.34
0.23
0.000*
Social context × difficulty × group
2, 116
0.32
0.00
0.73
Depicted emotion × social context × difficulty
2, 116
15.36
0.21
0.000*
Depicted emotion × social Context × difficulty × group
2, 116
0.43
01
0.65
Group (between-group factor)
1, 58
0.25
0.00
0.62
Depicted emotion
1, 58
0.31
0.01
0.58
Intensity of ratings
Depicted emotion × group
1, 58
2.19
0.04
0.14
Social context
1, 58
514.41
0.89
0.000*
Social context × group
1, 58
1.48
0.03
0.23
Difficulty
2, 116
258.92
0.82
0.000*
Difficulty × group
2, 116
0.02
0.00
0.98
Depicted emotion × social context
1, 58
7.92
0.12
0.01*
Depicted emotion × social context × group
1, 58
3.56
0.06
0.06
Depicted emotion × difficulty
2, 116
10.09
0.15
0.000*
Depicted emotion × difficulty × group
2, 116
0.19
0.00
0.82
Social context × difficulty
2, 116
15.36
0.21
0.000*
Social context × difficulty × group
2, 116
0.43
0.01
0.65
Depicted emotion × social context × difficulty
2, 116
17.34
0.23
0.000*
Depicted emotion × social Context × difficulty × group
2, 116
0.32
0.00
0.72
Group (between-group factor)
1, 58
9.20
0.14
0.000*
Depicted emotion
1, 58
7.67
12
0.01*
Confidence in rating
Depicted emotion × group
1, 58
0.21
0.00
0.65
Social context
1, 58
147.82
0.72
0.000*
Social context × group
1, 58
0.86
0.02
0.36
0.000*
Difficulty
2, 116
112.79
0.66
Difficulty × group
2, 116
3.04
0.05
0.05
Depicted emotion × social context
1, 58
8.32
0.13
0.01*
Depicted emotion × social context × group
1, 58
3.37
0.06
0.07
Depicted emotion × difficulty
2, 116
3.49
0.06
0.03*
Depicted emotion × difficulty × group
2, 116
0.33
0.01
0.72
Social context × difficulty
2, 116
12.20
0.17
0.000*
Social context × difficulty × group
2, 116
0.65
0.01
0.52
Depicted emotion × social context × difficulty
2, 116
17.69
0.23
0.000*
Depicted emotion × social Context*difficulty*group
2, 116
1.75
0.03
0.18
Analysis of variance; *p < 0.05.
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November 2014 | Volume 5 | Article 1262 | 5
Kaletsch et al.
Therefore, patients with BPD did not differ from HC in rating
valence.
The two-way interaction between social context and group
which was on the border of significance indicated that patients
with BPD rated monadic scenes, but not dyadic scenes, more negatively than HC, F(1,58) = 3.56, p = 0.064. All results of the
repeated measures ANOVAs are reported in Table 2. None of the
two-, three-, or four-way interactions (depicted emotion, social
context, difficulty) with group became statistically significant.
INFLUENCE OF GROUP ON INTENSITY OF RATINGS
Regarding the intensity of participants’ ratings on depicted emotion, ANOVAs revealed no significant main effect of group,
F(1,58) = 0.25, p = 0.616. Patients with BPD did not differ from
HC in intensity of ratings.
We found a tendency in the non-significant three-way interaction between social context, depicted emotion, and group indicating
that patients with BPD rated monadic scenes, but not dyadic
scenes as being more intense than HC did, but only if the depicted
emotion was negative, F(1,58) = 3.56, p = 0.064. The four-way
interaction (depicted emotion, social context, difficulty) with group
was not significant.
INFLUENCE OF GROUP ON CONFIDENCE IN RATINGS
There was a significant main effect of group membership on confidence in the rating of perceived emotional valence F(1,58) = 9.20,
p = 0.004. Patients with BPD rated depicted emotions less
confidently than HC (Figure 2).
Additionally, we found a tendency in the non-significant twoway interaction between difficulty and group, indicating that
patients with BPD became less confident about their ratings
as the depicted emotion became more difficult to recognize,
F(2,116) = 3.04, p = 0.052. None of the three- or four-way interactions (depicted emotion, social context, difficulty) with group were
significant.
DISCUSSION
The present study was conducted to investigate differences in the
perception of emotional body movements in patients with BPD.
Body language is a reliable source of information for assessing
FIGURE 2 | Average confidence ratings and standard deviations of
healthy controls (HCs) and patients with BPD. Error bars represent
standard error of mean. *The difference was significant at the 0.05 level.
Frontiers in Psychology | Emotion Science
Emotion perception in point–light displays
emotional states. It can convey emotions and may trigger more
complex behavioral responses within the observer than facial
expressions might do (de Gelder, 2006). Thereby it plays a significant role in the context of social interacting and functioning which
are domains in which many psychiatric patients encounter difficulties. However, until now, no study using PLDs has examined
the relationship between BPD and the perception of emotions presented solely through body movements without additional facial
expressions.
This study provided one major finding: In comparison to HC,
patients with BPD felt less confident when evaluating the depicted
emotional scenes. Although not statistically significant, however,
due to the exploratory nature of this work it is still noteworthy
that patients tended to become less confident the more difficult the
videos became to evaluate. Also not statistically significant but still
noteworthy was that there might be the effects that firstly, patients
with BPD rated monadic but not dyadic scenes more negatively;
and secondly, patients rated monadic scenes as being more intense.
These indications could be investigated in a subsequent study. To
sum up, the present work provides evidence that patients with
BPD differ in their feelings of confidence during perception of and
response to emotional body movements when they are presented
within a PLD paradigm. Less confidence in emotion perception
may lead patients to refrain from approaching social situations or
interactions or to behave less confidently within such situations.
This behavior, in turn, could have adverse effects on such or future
interactions.
When examining the first hypothesis that patients with BPD
would show a general bias when rating the emotional valence
of the depicted interactions, we found no differences between
groups. Thus, patients rated the emotions shown just as well
as HC. This was also true in regard to the factors difficulty,
social context and depicted emotion, which not lead to any significant group differences or interaction effects. Thus, and in
contrast to findings that reflect a biased or distorted emotion
perception, our findings are similar to those that patients did
not show general deficits in emotion recognition or a perception bias, especially toward negative emotions (Minzenberg et al.,
2006; Domes et al., 2008; Unoka et al., 2011; Robin et al., 2012;
Schilling et al., 2012; Sieswerda et al., 2013). Contrary to previous findings of a negatively biased perception of emotions in
patients with BPD (Arntz and Veen, 2001; Barnow et al., 2009;
Dyck et al., 2009; Baer et al., 2012) we were unable to detect
such a clear effect in this study as that found when applying
the same paradigm to a group of patients with major depressive disorder (Kaletsch et al., 2014). Whereas patients with major
depressive disorder may tend to perceive emotional interactions
with a negative bias on a more general level in line with a negative view of the world, people with BPD might show differential
effects not when observing but only when directly involved in an
interaction and therefore making the interaction more personally
relevant.
Even though it failed to attain significance, the two-way interaction between social context and group indicated that patients
with BPD rated monadic scenes but not dyadic scenes more negatively than HC. This effect, however, only indicated a trend and
future research could investigate the relationship between aversive
November 2014 | Volume 5 | Article 1262 | 6
Kaletsch et al.
feelings when being lonely, empathy, and the number of persons
observed.
We also could not confirm our second hypothesis that patients
with BPD would perceive emotional interactions as being more
intense than HC would. This is in line with research reporting
an inability to detect a dichotomous or extremely intense evaluation style in BPD patients (Veen and Arntz, 2000; Sieswerda et al.,
2013). Contrary to previous findings of a more extreme evaluation of personality traits we did not detect such an effect in this
study as that found when applying the same paradigm to a group
of patients with major depressive disorder (Kaletsch et al., 2014).
Whereas patients with major depressive disorder may tend to perceive negative emotional interactions more intense, people with
BPD might show differential effects not when observing but only
when directly involved in an interaction and therefore making the
interaction more personally relevant. The non-significant interaction for the intensity of ratings indicated that patients with BPD
rated monadic scenes as being more intense, but only when the
depicted emotional scene was negative.
The most important finding in the present study is that patients
with BPD were significantly less confident when perceiving and
evaluating the depicted emotional scenes. This lack of confidence
in perceiving emotional body movements may be based on a history of invalidating, instable, and confusing emotional experiences
gained with, for example, attachment figures who provided unreliable emotional responses. This insecurity, in turn, could lead
to less confidence in evaluating personal interactions (Fonagy,
2000). Such a pattern of emotion perception combined with a high
need for self-protection could lead to insecure or less competent
behavior within social interactions, to withdrawal, or to avoidance
behavior (Newman et al., 2007). In the long term, feelings of insecurity may lead to lower self-confidence and self-efficacy, negative
and instable affect, or states of emotional dysregulation (Johnson
et al., 2002; Fruzzetti et al., 2005).
Interestingly, even though it failed to attain significance the
two-way interaction between difficulty and group indicated that
patients with PBD became less confident as the depicted emotion
became more difficult to recognize. This could imply that patients
are more confident when depicted emotions are strong and expressive, as they often experience them to be for themselves, or people
in interactions with patients often might have expressed them, but
become less confident, the more subtle and sensitive the expressed
emotions are. This might be understood against the background
that patients often have a history of violence, abuse and extreme
emotions in the past, so that they might be more familiar with this
kind of emotion information and therefore might have difficulties
in assessing ambiguous, difficult or rather less extreme emotions
(Zanarini, 2000; Lieb et al., 2004; Barnow et al., 2005).
Contrary to our results Schilling et al. (2012, 2013) found that
patients with BPD showed more confidence than controls when
completing the Reading the Mind in the Eyes Test (Baron-Cohen
et al., 2001) and during a false memory paradigm whose stimuli
differed greatly from those used in the present experiment. However, they assessed confidence in a similar way to our paradigm
only in the Reading the Mind in the Eyes Test, and compared
their answers only within the highest confidence category between
groups, whereas, in our analysis, we compared mean confidence
www.frontiersin.org
Emotion perception in point–light displays
values. Perhaps patients are much less confident when observing
a social and emotional interaction compared to a static image. A
comparison study could shed light on this issue. Schilling et al.
(2012) discussed a possible overconfidence bias or a possible tendency to respond in extreme ways. We could not find evidence for
either an overconfidence bias or en extreme response or evaluation style while rating emotional valence or in regard to intensity
of ratings.
LIMITATIONS AND FURTHER DIRECTIONS
A limitation of this study is that our findings are not undoubtedly
specific for emotion recognition tasks but are linked to overall reduced feelings of confidence in patients with BPD while
performing the task. In subsequent studies this effect should
be investigated by including a non-emotional recognition task
as control condition. If the effect turns out to be specific, it
would be necessary to examine why and under what conditions
patients show this lack of confidence and how it is acquired. Further research should investigate the possible consequences of an
uncertain perception of emotional body movements in personal
interactions and how this may contribute to the perpetuation of
BPD. How does lower confidence influence social interactions?
How does it influence a patient’s self-concept and how, if these
effects are harmful, can it be addressed in a therapeutic context?
Another interesting approach is to adapt the paradigm so that the
proband gets addressed by a counterpart and thereby would be
directly involved into the interaction.
Due to the novelty of this approach to asses emotion perception processes within clinical samples using PLDs, we also have
reported and mentioned non-significant results on the border of
significance, which may provide useful information and may be
further investigated in subsequent studies. It could be a lack of
power to be responsible for the missing statistical significance,
which could be adjusted in subsequent studies by enlarging the
relevant samples.
CONCLUSION
This is the first study to investigate differences between patients
with BPD and HCs when perceiving emotions expressed solely via
body movements conveyed by PLDs. First and foremost, we have
demonstrated that patients with BPD are less confident when perceiving and evaluating emotional scenes, and that their confidence
declines the more difficult the emotional scenes become. Additionally, unlike patients with major depressive disorder (Kaletsch
et al., 2014), BDP patients do not reveal an altered emotion perception; that is, any biased perception in either a negative or a
positive direction. However, they do show a tendency to evaluate monadic stimuli more negatively. Further, in general, BDP
patients do not perceive and evaluate depicted emotions more
extremely in the sense of a dichotomous thinking but tend to evaluate monadic scenes as being more intense when the depicted
emotion is negative.
ACKNOWLEDGMENTS
The authors thank Matthias Bischoff, Helge Gebhardt, Fabian
Helm, Stefan Kindermann, Isabell Sauerbier, Kristina Stephan,
and Sonja von Usslar for their helpful support. We thank Jonathan
November 2014 | Volume 5 | Article 1262 | 7
Kaletsch et al.
Harrow for native-speaker advice and all participants for taking
part in our study.
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Conflict of Interest Statement: The authors declare that the research was conducted
in the absence of any commercial or financial relationships that could be construed
as a potential conflict of interest.
Received: 24 July 2014; accepted: 17 October 2014; published online: 04 November
2014.
Citation: Kaletsch M, Krüger B, Pilgramm S, Stark R, Lis S, Gallhofer B, Zentgraf K,
Munzert J and Sammer G (2014) Borderline personality disorder is associated with
lower confidence in perception of emotional body movements. Front. Psychol. 5:1262.
doi: 10.3389/fpsyg.2014.01262
This article was submitted to Emotion Science, a section of the journal Frontiers in
Psychology.
Copyright © 2014 Kaletsch, Krüger, Pilgramm, Stark, Lis, Gallhofer, Zentgraf, Munzert
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