Mindfulness DOI 10.1007/s12671-016-0572-2 ORIGINAL PAPER Behavioral Assessment of Mindfulness Difficulties in Borderline Personality Disorder Hannah J. Scheibner 1 & Stefanie Spengler 2 & Phillipp Kanske 3 & Stefan Roepke 4 & Felix Bermpohl 1,2 # Springer Science+Business Media New York 2016 Abstract Although mindfulness plays an important role in the treatment of borderline personality disorder (BPD), few studies have investigated whether individuals with BPD show difficulties in mindfulness. Those studies have relied exclusively on questionnaire data. Here, we used a more objective, behavioral assessment of mindfulness difficulties in BPD that allowed us to distinguish difficulties in mindfulness, prolonged mindwandering, and difficulties in awareness of mind-wandering. Twenty-five individuals with BPD and 28 healthy controls performed two mindful breathing tasks. Frequency of mindfulness versus mind-wandering was assessed in the experimenterprompted mindfulness task, where participants were interrupted at random intervals and asked whether they had just been mindful or mind-wandering. Awareness of mindwandering was assessed in the self-prompted mindfulness task, where participants were asked to press a computer key whenever they noticed mind-wandering. Length of mind-wandering was assessed in both tasks. In individuals with BPD, we found Electronic supplementary material The online version of this article (doi:10.1007/s12671-016-0572-2) contains supplementary material, which is available to authorized users. * Hannah J. Scheibner hannahscheibner@posteo.de 1 Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099 Berlin, Germany 2 Department of Psychiatry and Psychotherapy, Charité Universitätsmedizin Berlin, Campus Mitte, Berlin, Germany 3 Department of Social Neuroscience, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany 4 Department of Psychiatry and Psychotherapy, Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany a lower frequency of mindful episodes. In addition, individuals with BPD indicated longer mind-wandering episodes in the experimenter-prompted task. However, individuals with BPD detected mind-wandering episodes as accurately as healthy controls in the self-prompted task. Finally, difficulties in mindfulness observed in the behavioral tasks positively correlated with participants’ reports of mindfulness difficulties in everyday life. Using behavioral tasks to specify difficulties in mindfulness in BPD, this study indicated that although individuals with BPD mind-wander longer and more often, their awareness of mind-wandering appear unaffected. This indicates that mindfulness difficulties can be reported by individuals with BPD and that therapists can build on this awareness through mindfulness-based treatments of BPD. Keywords Mindfulness . Mind-wandering . Borderline personality disorder . Behavioral research Introduction Borderline personality disorder (BPD) is a complex, serious mental illness characterized by pervasive patterns of instability in emotion regulation, impulse control, interpersonal relationships, and self-image (Skodol et al. 2002; Lieb et al. 2004; Leichsenring et al. 2011). The disorder puts a heavy burden on its patients and on society, as treatment often takes years (Zanarini et al. 2003) and incurs high annual medical costs (Wagner et al. 2015). Consequently, studying the underlying factors that play a role in borderline personality disorder is an important task in clinical research: one such factor may be patients’ difficulty in staying focused on experiences in the present moment (Linehan 1994). These difficulties have been described as difficulties in mindfulness (Wupperman et al. 2008, 2009). Mindfulness Mindfulness, a concept derived from the Buddhist tradition, has been defined in modern Western psychology as non-judgmental attention to and awareness of the present moment (Kabat-Zinn 1994). It stands in stark contrast to a key problem for individuals with BPD: to pay attention to and be aware of their own feelings and emotions. While self-reports of patients with BPD suggest that they experience difficulties in staying mindful (Baer et al. 2004), this has never been investigated using a more objective, behavioral assessment. Behavioral mindfulness exercises have been implemented in several new psychotherapies, including dialectical behavior therapy (Linehan et al. 2007; Soler et al. 2012), acceptance and commitment therapy (Hayes et al. 2006; 1999), and mindfulness-based cognitive therapy (Williams and Swales 2004; Sachse et al. 2011), all of which have been effective in treating BPD. For example, in DBT, mindfulness is taught as a set of skills that evolve around a mindful attitude (wisemind), acceptance and non-judgment, as well as mindfulness exercises fostering mindful attention (mindful observing, describing, participating) (Linehan 1993; Welch et al. 2006). Mindfulness exercises include focused-attention mindfulness exercises, in which practitioners learn to concentrate on one particular momentary experience, such as sensing their own breath. Practitioners aim to focus on the given experience for as long as possible. As soon as their thoughts wander off and they notice that they are no longer focused on the experience, practitioners non-judgmentally and calmly return their focus to the momentary experience. With practice, this simple exercise trains practitioners to stay mindful for a prolonged period of time. Mindfulness exercises consist of at least three distinct phases (Hasenkamp et al. 2012): (1) mindfulness—the phase during which the practitioner succeeds in focusing on the present moment; (2) mind-wandering—the phase during which the practitioner’s mind wanders off; and (3) awareness of mind-wandering and refocusing—the phase during which the practitioner becomes aware of the mind-wandering and then returns to the mindfulness task. A similar process can be observed in everyday life, when people shift between being concentrated on their momentary experience, drifting off, and becoming aware of mind-wandering. Consequently, if practitioners experience mindfulness difficulties, these may arise in any of the three phases, i.e., difficulties in focusing on the present moment, prolonged periods of mind-wandering, and difficulties in awareness of mind-wandering. Although mindfulness plays an important role in BPD treatment, it is not clear whether patients with BPD actually experience more difficulties in mindfulness than healthy individuals. To date, few studies have examined whether BPD may be specifically associated with mindfulness difficulties. While individuals with BPD may benefit from mindfulness training, even if they do not experience more mindfulness difficulties compared to healthy controls, it is of scientific and clinical relevance to elucidate potential mindfulness differences in BPD. Without exception, studies that have examined mindfulness difficulties in patients with BPD have relied on questionnaires: Wupperman et al. (2008, 2009, 2013) showed that participants with BPD traits scored low on the Mindful Attention Awareness Scale, a questionnaire that measures trait mindfulness (Brown and Ryan 2003). Lower scores on the mindfulness questionnaire were not only related to higher scores on BPD traits, but also predicted greater deficits in emotion regulation and interpersonal problem solving. Similarly, Baer et al. (2004) reported that patients with BPD scored lower on four out of five subscales of the Kentucky Mindfulness Inventory compared to two student samples. While mindfulness questionnaires, as employed in these previous mindfulness studies in BPD, are valuable and useful in screening mindfulness difficulties and developing treatment-related mindfulness improvements, a potential challenge with mindfulness questionnaires is that subjects differ widely in their conceptual understanding of mindfulness (Grossman 2008; Sauer et al. 2013). This may impact subjects’ understanding of the questionnaires. Individuals with difficulties in mindfulness may not be aware of their difficulties at all and thus would have difficulties reporting them (Burg and Michalak 2011). Additionally, to improve mindfulness training in BPD, it seems critical to understand which aspect of mindfulness is affected, that is, to understand whether individuals with BPD have difficulties in staying mindful, have difficulties in becoming aware of mind-wandering, or experience prolonged periods of mind-wandering. While no previous research has investigated whether individuals with BPD are less aware of mind-wandering, Fonagy and Bateman (2007, see also: Choi-Kain and Gunderson 2008) have argued that individuals with BPD have an unstable capacity for mentalization, which includes an unstable ability to be aware of their own mental processes. To summarize, additional methods of assessing different aspects of mindfulness in a more objective manner are required. One alternative to questionnaires is the behavioral assessment of mindfulness, either via thought probes over the course of the day or via thought probes during mindfulness exercises. Thought probes during mindfulness exercises, especially, may help to assess different aspects of mindfulness. Both types of behavioral assessment have so far only been studied in healthy individuals, but not in BPD. Killingsworth and Gilbert (2010) developed a smartphone app to sample participants’ thoughts, feelings and activities in everyday life. They found that independent of the type of activity, participants were less happy when their minds were wandering. Burg and Michalak (2011) and Frewen et al. (2008, 2011, 2014) collected thought probes during mindfulness exercises, employing an experimenter-prompted mindfulness task. They asked healthy participants to perform a focused-attention practice, Mindfulness during which participants were interrupted multiple times. Participants had to report whether they were in a mindful or mind-wandering state at the moment they were interrupted. These studies showed that the ratio of mindful versus mindwandering moments was correlated with data from mindfulness questionnaires as well as certain aspects of well-being (Frewen et al. 2011). Using a self-prompted mindfulness task, Hasenkamp et al. (2012) asked experts to perform a focusedattention meditation exercise. In this study, participants were not interrupted by experimenters, but rather had to press a button whenever they noticed that they had just been mindwandering. The investigators argued that this moment of selfprompted interruption indicated the awareness and refocusing phase between a mind-wandering phase and a new mindfulness phase. Employing this task for fMRI, they identified distinct neural correlates of these three phases, supporting the idea that mindfulness, mind-wandering, becoming aware of mind-wandering, and refocusing are separate processes. In the current study, our aim was to assess mindfulness difficulties in BPD with an objective behavioral mindfulness task, allowing us to investigate different phases of mindfulness exercises: mindfulness, mind-wandering and awareness of mind-wandering. Specifically, we asked participants to perform a focused-attention exercise similar to Burg and Michalak (2011) and Frewen et al. (2008, 2011, 2014) and Hasenkamp et al. (2012). During the first exercise (experimenter-prompted mindfulness task), participants were interrupted at random intervals and asked whether they were just mindful or mind-wandering, and if they were mind-wandering, for how long they had mind-wandered. During the second exercise (self-prompted mindfulness task), participants were asked to interrupt themselves whenever they became aware of mind-wandering and report length of mind-wandering. The thought probes allowed us to assess frequency of mindfulness and mind-wandering, length of mind-wandering, and awareness of mind-wandering. We hypothesized that individuals with BPD were (1) less frequently mindful, (2) were less aware of mind-wandering, and (3) showed longer mindwandering periods than healthy controls. Method Participants Twenty-six individuals with borderline personality disorder (BPD) according to DSM-IV (American Psychiatric Association 1994) and 30 healthy controls were recruited for the study. Individuals with BPD were recruited from local hospitals as well as via online advertisement. Healthy controls were recruited via online advertisement. One individual with BPD and two healthy controls were excluded due to technical problems during data collection, leaving 25 individuals with BPD and 28 healthy controls. Diagnosis of BPD was established using the Structural Clinical Interview II for DSM-IV (First et al. 1997). Participants were screened for comorbidity using the Structural Clinical Interview I and II (First et al. 1997; First et al. 1998; Wittchen et al. 1997) and the Mini-International Neuropsychiatric Interview (Sheehan et al. 1998; Ackenheil et al. 1999). Three trained clinical psychologists administered all clinical interviews. BPD and control participants were included when they reported to have little to no experience in mindfulness exercises, i.e., less than 10 h of lifetime mindfulness training, and no mindfulness training within the last 3 months. Healthy control participants had to have no current or past mental illness according to DSM-IV. Exclusion criteria for individuals with BPD included bipolar disorder, current major depression, psychotic disorder, a body mass index below 18, or current alcohol or substance dependence. Five individuals with BPD were diagnosed with current PTSD, one individual met the diagnosis of current panic disorder, seven individuals met the diagnosis of agoraphobia, five individuals met the diagnosis of social phobia, and two individuals met the diagnosis of bulimia nervosa. Twelve individuals with BPD also met the diagnosis of one or more additional personality disorders: avoidant personality disorder (n = 6), paranoid personality disorder (n = 6), and obsessive-compulsive personality disorder (n = 3). Individuals with BPD and control participants did not significantly differ in age, sex, or level of education. For the pu rp ose of samp le d esc rip tion , we ass esse d t he Montgomery–Åsberg Depression Rating Scale (MADRS) (Montgomery and Asberg 1979) and the Borderline Symptom List-23 (Bohus et al. 2008), as well as the verbal intelligence test (BWortschatztest^) (Schmidt and Metzler 1992) and the general attention and concentration test (Bd2^) (Brickenkamp 1962). For a summary of sample characteristics, see Table 1. Procedure The study design was reviewed by the local ethics committee and the investigation was carried out in accordance with the latest version of the Declaration of Helsinki. Informed consent of the participants was obtained prior to participation and after the nature of the procedures had been fully explained. The experiment took place in a research wing at the local hospital. Here, participants were tested individually and in a semisoundproof room. All participants were tested between 3:30 and 4:30 p.m., and the timing of the interruptions during the mindfulness exercise was the same for all participants. At the beginning of a test session, participants filled out the two mindfulness questionnaires as well as the borderline symptom list (BSL)-23 and the vocabulary test. Participants then learned the mindfulness breathing exercise. The instructions Mindfulness Table 1 Sample characteristics BPD (n = 25) Control group (n = 28) Test for group differences Sex, n Female 20 21 X2(1) = 0.189, p = 0.750 Male Age, years 5 36.44 (9.87) 7 33.75 (11.2) t(51) = 0.923, p = 0.361 range Years of education 23–59 11.76 (1.49) 19–63 11.85 (1.43) t(51) = −0.243, p = 0.809 7.04 (1.40) 0.14 (0.45) t(51) = 24.73, p < 0.0005 1.89 (0.67) 12.86 (8.25) 0.16 (0.17) 0.84 (1.27) t(51) = 13.13, p < 0.0005 t(51) = 7.621, p < 0.0005 106.2 (9.77) 96.72 (10.61) 104.11 (12.41) 100.82 (9.67) t(51) = 0.68, p = 0.502 t(51) = −1.47, p = 0.147 Number of BPD criteria BSL-23 MADRS Verbal intelligence score, BWortschatztest^ Attention and concentration score, Bd2^ Data are given as mean (standard deviation) unless otherwise specified BPD borderline personality disorder, n subsample size, BSL-23 borderline symptom list, MADRS MontgomeryÅsberg Depression Rating Scale, BWortschatztest^ verbal intelligence test, Bd2^ general attention and concentration test for this were recorded by a certified mindfulness trainer and played to participants via earphones and simultaneously presented on the computer screen. Participants first practiced the breathing exercise for 3 min. For all mindfulness exercises, participants were left alone in the room. After 3 min, the experimenter entered, repeated the instructions of the certified trainer and asked if participants had any more questions about the exercise. Participants then performed the experimenterprompted mindfulness task. After a short break, participants received instructions for the self-prompted mindfulness task that were again repeated by the experimenter. Then, participants performed the self-prompted mindfulness task. Experimenter-Prompted Mindfulness Task Participants performed a mindful breathing exercise. They were instructed to focus their attention on the sensation of their breathing. Whenever participants became aware that their attention wandered off task, they were asked to calmly and nonjudgmentally return their attention to their breathing. During the exercise, interruptions induced by a computer-triggered meditation bell ring (Fig. 1) prompted participants to indicate where their attention was when the bell rang. Participants answered using the computer keyboard (1 = Bfocused on their breathing^, 2 = Bdistracted^). When participants indicated that they had been distracted, they further indicated for how long they had been distracted (1 = B1–5 s^, 2 = B5–30 s^, 3 = Bmore than 30 s^). After participants had answered the questions, they continued the mindful breathing exercise until they were interrupted again. In total, participants were interrupted 13 times within 20 min. The time between interruptions varied between 30 s and 3 min. Outcome variables analyzed in the experimenter-prompted mindfulness task included the frequency of mind-wandering and mindful episodes and the self-reported duration of mind-wandering. Note that frequency of mind-wandering and mindful episodes are inversely related to each other in our task and cannot be disentangled. Self-Prompted Mindfulness Task Participants performed a mindful breathing exercise with selfprompted interruptions (Fig. 1). Participants focused their attention on the sensation of their breathing. Whenever participants became aware that their attention had wandered off from the task, they were asked to press a computer key. They should then further indicate how long they had mind-wandered (1 = 1–5 s, 2 = 5–30 s, 3 = more than 30 s). After participants answered this question, they continued with the mindful breathing exercise until they again noticed that they had mindwandered and again pressed a computer key. In total, the exercise lasted 20 min. Outcome variables analyzed in the selfprompted mindfulness task included the number of computer key presses (awareness of mind-wandering), reported duration of mind-wandering, and the awareness coefficient. The selfprompted mindfulness task allowed us to assess how often participants became aware of their own mind-wandering. Besides identifying how often participants became aware of mind-wandering, we intended to account for differences in overall percentage of mind-wandering. The following example may illustrate why this was critical in the present study: If two participants A and B are equally aware of mind-wandering, but participant A mind-wanders on average 40 % of the time, participant A is twice as likely to detect mind-wandering compared to participant B who mind-wanders on average only 20 % of the time. To account for differences in percentage of mind-wandering during the experiment, we calculated the Bawareness coefficient.^ The awareness coefficient consists of the number of noticed mind-wandering episodes in the Mindfulness A Experimenter-Prompted Mindfulness Task Where was your mind right now? How long have you been mindwandering? 30 sec – 180 sec B Self-Prompted Mindfulness Task How long have you been mindwandering? self-paced interval Fig. 1 The experimenter-prompted mindfulness task (a) and the selfprompted mindfulness task (b). When participants heard the bell ring, they closed their eyes and performed the mindful breathing meditation. In the experimenter-prompted mindfulness task, another bell interrupted participants after 30–180 s. They then had to indicate where their thoughts were at the moment of interruption (mindful or mind-wandering) and, if they were mind-wandering, report for how long they had been mindwandering. In the self-prompted mindfulness task, participants themselves pressed a computer key whenever they noticed that they had been mind-wandering and further reported for how long they had been mindwandering self-prompted mindfulness task divided by the percent of mind-wandering episodes in the experimenter-prompted mindfulness task. A higher score indicates more awareness of mind-wandering. After the two behavioral mindfulness tasks, participants performed the d2 attention and concentration test and the diagnostic interview. experiencesB) and presence (e.g., BI watch my feelings without getting lost in them^). Items are rated on a 4-point Likert scale from Brarely^ (1) to Balmost always^ (4). Both questionnaires are targeted to non-mindfulness-practitioners. Measures All analyses were conducted using SPSS statistics 22.0 software package for Windows and all hypotheses were tested with a two-sided significance level of α = 0.05. To test whether individuals with BPD are less frequently mindful and mindwander more often, we compared the two groups with regard to the amount of mind-wandering and mindful episodes, respectively. For this purpose, we computed participants’ mean frequency of mind-wandering across all 13 trials in the experimenter-prompted task, and compared the groups using an independent samples t test. To study participants’ awareness of mind-wandering, we computed the sum of self-prompted interruptions in the self-prompted mindfulness task for each participant. Then, we tested for group differences using an independent samples t test. In addition, we compared awareness of mind-wandering independent of differences in mindwandering by comparing participants’ awareness coefficient (see earlier). We again employed an independent samples t test to analyze group differences on the awareness coefficient. To test whether participant groups differed in length of mind-wandering, we used a Mann–Whitney U test with median length of Mindfulness Questionnaires In order to compare participants’ performance on the two mindfulness tasks to questionnaire data, we administered the Mindfulness Attention Awareness Scale (MAAS), as well as the Short Version of the BFreiburger Fragebogen zur Achtsamkeit^ (Freiburg mindfulness inventory) (FFA). The MAAS (Brown and Ryan 2003; Michalak et al. 2008) is a questionnaire that assesses mindfulness in everyday life. It consists of 15 negatively posed items (e.g., BI find it difficult to stay focused on what is happening in the present^ or BI do jobs or tasks automatically, without being aware of what I am doing^). On a 6-point Likert scale from Balmost always^ (1) to Balmost never^ (6), participants indicated how frequently they had the respective experiences in everyday life. The FFA (Buchheld et al. 2001; Walach et al. 2006) employed in the present study is a 14-item short version. It consists of two subscales: acceptance (e.g., BI accept unpleasant Data Analyses Mindfulness Results Mindfulness and Mind-Wandering Episodes We found that individuals with BPD were less often mindful than control participants (t(51) = −4.09, p < 0.0005). On average, control participants were mindful during 52 % of the trials (M = 52.47, SD = 15.81) whereas individuals with BPD were mindful during 32 % of the trials (M = 32, SD = 20.55) (Fig. 2a). Conversely, control participants were mindwandering during 48 % and individuals with BPD during 68 % of all trials (Fig. 2b). Awareness of Mind-Wandering Episodes Length of Mind-Wandering Episodes In the experimenter-prompted mindfulness task, individuals with BPD reported longer mind-wandering periods than healthy controls (MdnBPD = 2 vs. Mdncontrol = 1.5, U = 232, p = 0.028). In the self-prompted mindfulness task, however, we did not find a significant difference in mind-wandering length (Mdn BPD = 2 vs. Mdn control = 1.25, U = 329, p = 0.671) (Fig. 2e). Potential Duration Effects Within Each Mindfulness Exercise One additional concern we wanted to address was whether the difference between BPD patients and healthy controls (HCs) 100 80 A * 60 40 100 * 60 40 20 0 0 Mind-wandering Episodes (Experimenter-Prompted Mindfulness Task) * C 30 20 10 Count / Percent Mindful Episodes (Experimenter-Prompted Mindfulness Task) 40 0 B 80 20 50 1.0 ns. 0.8 D 0.6 0.4 0.2 0.0 Awareness Coefficient Awareness of mind-wandering (Self−Prompted Mindfulness Task) E 3 BPD HC Median Count (n) Fig. 2 BPD borderline personality disorder. Asterisk significant group differences from two-tailed independent t tests at p < 0.05. a–d Values are means, with standard deviations represented by vertical bars. e A box plot displays median and interquartile range. a Compared to a healthy control group, individuals with borderline personality disorder (BPD) were less frequently mindful and b more often mind-wandering in the experimenter-prompted mindfulness task. c Awareness of mind-wandering episodes was assessed in the self-prompted mindfulness task; individuals with BPD detected more mind-wandering episodes than healthy controls. d However, when number of mind-wandering episodes was accounted for, groups did not differ in detected mind-wandering episodes, i.e., in the awareness coefficient. e Individuals with BPD mindwandered longer than the control group in the experimenterprompted mindfulness task, but not in the self-prompted mindfulness task Percent % We found that individuals with BPD detected more episodes of mind-wandering than healthy controls (MBPD = 26.16, SDBPD = 15.42 vs. Mcontrol = 16.32, SDcontrol = 10.19, t(51) = 2.77, p = 0.008) (Fig. 2c). The awareness coefficient did not differ significantly between groups (MBPD = 0.38, SDBPD = 0.18 vs. Mcontrol = 0.36, SDcontrol = 0.22, t(51) = .349, p = 0.729) (Fig. 2d). This indicates that the BPD and the control group did not differ significantly in detecting mind-wandering, when the analysis was controlled for the mind-wandering frequency. Figure 3 illustrates periods of mind-wandering and mindfulness in the self-prompted mindfulness task, as derived from participants’ key presses and reported length of mindwandering. Percent % mind-wandering as the dependent variable and group (BPD vs. healthy controls) as the independent variable. 2 1 Lenght of Mind-wandering, Boxplot (Left: Experimenter-Prompted Mindfulness Task Right: Self-Prompted Mindfulness Task) Mindfulness Fig. 3 BPD borderline personality disorder. HC healthy control. Mindfulness and mindwandering phases are displayed based on the participants’ key presses and the self-reported length of mind-wandering in the self-prompted mindfulness task. Each row represents one participant, with the upper rows representing healthy control participants and the lower rows borderline personality disorder participants. White represents mindfulness and black mind-wandering phases. The middle two rows represent the averaged mind-wandering of each group at each time point, darker color indicating more mindwandering, lighter color indicating less mind-wandering. For illustration purposes, B1–5 s^ was equaled to 5 s, B5–30 s^ was equaled to 20 s, and Bmore than 30 s^ was equaled to 40 s or since the last computer key press, if this was less than 40 s apart was more pronounced toward the end of each mindfulness exercise. Frewen et al. (2011, 2014) used a similar paradigm as our experimenter-prompted paradigm and found good construct validity (Frewen et al. 2011) and test-retest reliability (Frewen et al. 2014) for a 15-min task. Several other studies have asked meditation novices to perform mindfulness exercises of 20 min or longer (e.g., Johnson et al. 2015; Prätzlich et al. 2016; Fennell et al. 2016). However, since we here assess mindfulness difficulties in a patient group, patients may have particular difficulties with the exercise length. For this purpose, we compared performance in the first and second half of each exercise between groups. A detailed description of results can be found in the Supplemental material. In sum, group differences existed in both the first and second half of each mindfulness exercise. The only difference was found in the length of mind-wandering in the self-prompted mindfulness task. Here, individuals with BPD reported to mindwander longer than HC in the first but not second half of the task. lower scores on both questionnaires (MAAS: t(51) = −8.69, p < 0.0005 and FFA: t(51) = −8.74, p < 0.0005). In the FFA, the group difference was found on both subscales (acceptance: t(51) = −7.3, p < 0.0005 and presence: t(51) = −7.76, p < 0.0005). Across groups, the percentage of mindful episodes in the experimenter-prompted mindfulness task was positively correlated with both the MAAS and the FFA (r = 0.545, p < 0.0005 and r = 0.282, p = 0.041, respectively) (Table 2). The more mindful participants were in the experimenterprompted mindfulness task, the fewer mindfulness difficulties they reported in the questionnaires. Length of mind-wandering was not correlated with scores on the mindfulness questionnaires. In the self-prompted mindfulness task, number of detected mind-wandering episodes was negatively correlated with the MAAS score (r = −0.419, p = 0.002) as well as the FFA score (r = −0.320, p = 0.019) (Table 2). The more mind-wandering episodes participants reported, the less mindfulness they reported in the questionnaire. There was no correlation between the questionnaire score and the awareness coefficient (MAAS: r = −0.058, p = 0.681, FFA: r = −0.172, p = 0.218). Mindfulness Difficulties in Everyday Life To test whether the differences observed in our behavioral tasks were paralleled by findings in questionnaires assessing mindfulness in everyday life, we compared scores on the mindfulness questionnaires between groups. Individuals with BPD showed Influence of Attention, Intelligence, Depression, or Demographic Variables on Task Performance Groups did not differ in sex, age, level of education, verbal intelligence, or d2 score (Table 1). We did not find any effects Mindfulness Table 2 Inter-correlations for main study variables Correlation coefficients 1 1. Mindful episodes 2 3 4 – (Self-prompted mindfulness task) 2. Awareness of mind-wandering −0.483** (Experimenter-prompted mindfulness task) 3. Awareness coefficient 4. MAAS 5. FFA 0.105ns 0.545** 0.282* – 0.772** −0.419** −0.320* – −0.058ns −0.172ns – 0.566** Inter-correlations for main study variables. Pearson’s r correlation coefficients are displayed MAAS Mindfulness Attention Awareness Scale, FFA Freiburg Mindfulness Inventory, ns not significant **p < 0.01, *p <0 .05 of sex, age, or level of education on measures of mindfulness. Since our male sample was very small, future studies are needed to explore in how far participants’ sex influences mindfulness difficulties. Individuals with BPD scored higher on the MADRS than control participants. We reanalyzed all statistical tests, with verbal intelligence, d2 score, and MADRS entered as covariates. The group differences reported earlier remained significant when each of these covariates was controlled for. Discussion This is the first study using behavioral mindfulness tasks to investigate difficulties in mindfulness in BPD. We found that individuals with BPD were less frequently mindful than a control group in a mindful breathing exercise, the experimenter-prompted mindfulness task. In the experimenter-prompted mindfulness task, individuals with BPD mind-wandered not only more often, but also longer. Although individuals with BPD had difficulties staying focused on their breathing, they did not have difficulties in becoming aware of mind-wandering in the self-prompted mindfulness task. The group differences observed in our mindfulness tasks was not due to non-specific differences in education, age, or verbal intelligence. Taken together, these results suggest specific difficulties in mindfulness in BPD. While previous mindfulness studies in BPD exclusively relied on questionnaire data (Baer et al. 2004; Wupperman et al. 2008, 2009, 2013), here, we employed a behavioral mindfulness task. The behavioral assessment of mindfulness offers several advantages. First, behavioral mindfulness tasks allow us to disentangle different aspects of mindfulness, namely: difficulties in being mindful, duration of mind-wandering, and awareness of mind-wandering. We found a characteristic pattern of mindfulness difficulties in BPD: individuals with BPD mind-wandered more frequently and longer, documenting difficulties in being mindful. At the same time, they also detected their mind-wandering more frequently. Consequently, individuals with BPD seem to have difficulties in staying mindful, but not in awareness of mind-wandering. Second, behavioral mindfulness tasks offer a more objective measure of mindfulness compared to mindfulness questionnaires. It may be argued that findings from mindfulness questionnaires are potentially confounded by interindividual differences in awareness of mind-wandering in everyday life. Interestingly, in our behavioral tasks, we did not find such differences in the awareness of mind-wandering. The awareness coefficient did not differ between groups. Therefore it seems likely that questionnaire data in BPD are not to a great extent confounded by differences in awareness of mind-wandering. In accordance with these considerations, we found that behaviorally assessed mindfulness difficulties were associated with mindfulness difficulties on two established mindfulness questionnaires, the MAAS and the FFA. In conclusion, mindfulness difficulties identified in our more objective behavioral task under experimental conditions corresponded to questionnaire data, capturing difficulties subjectively experienced in everyday life. Our findings suggest that both questionnaires and behavioral tasks may similarly be used to assess mindfulness difficulties in BPD. Third, the behavioral mindfulness task provides a relatively sensitive tool to quantify mindfulness, mind-wandering, and awareness of mind-wandering. This tool can, in the future, be used to characterize and compare mindfulness difficulties in further patient populations that might show different patterns of mindfulness difficulties (cf. Williams 2008, for depression; Fossati et al. 2012, for other personality disorders; and Smalley et al. 2009, for ADHD). In addition, this tool can be used in BPD to investigate which aspects of mindfulness improve after mindfulness training and which aspect of the task is particularly predictive of clinical improvements. Some limitations of our study should be pointed out. First, the two behavioral mindfulness tasks revealed discrepant findings regarding the length of mind-wandering episodes. In the experimenter-prompted mindfulness task, individuals with BPD mind-wandered not only more often, but also longer. This finding was not paralleled in the self-prompted Mindfulness mindfulness task where durations of mind-wandering did not differ significantly between groups. A possible explanation for this discrepancy between tasks is that the emphasis on awareness of mind-wandering in the self-prompted mindfulness task may have helped individuals with BPD to interrupt mind-wandering and thus reduce the length of mindwandering episodes. Another explanation may be that the order of experimental tasks affected participants’ performance. In our study, the experimenter-prompted task was always assessed before the self-prompted task. Indeed, exploratory post hoc analyses revealed that individuals with BPD and healthy controls differed in length of mind-wandering in the first half of the self-prompted task, but not in the second half of the self-prompted task (see Supplemental material). A second limitation is that, similar to behavioral mindfulness tasks previously studied in healthy participants, we used a focused-attention breathing exercise to assess mindfulness, mind-wandering, and awareness of mind-wandering. We acknowledge that other mindfulness exercises exist that could have yielded different results. For example, participants could be asked to mindfully focus on other internal sensations, such as their own heartbeat or bodily sensations. Farb et al. (2015) argue that Bthe relationship between interoceptive constructs across domains … is largely unknown^ (p. 3). Indeed, a study that examined participants’ awareness of heartbeat via the heartbeat perception task did not find any difference between individuals with BPD and healthy controls (Hart et al. 2013). Two other studies found that while patients with BPD had impaired pain perception, patients’ proprioception and exteroceptive sensitivity was not impaired (Pavony and Lenzenweger 2013; Cárdenas-Morales et al. 2011). In addition, we instructed participants to report mind-wandering, which may have prompted participants to monitor mindwandering more closely than they would in everyday life. Given such discrepant findings, future research is needed to explore in how far our results can be generalized to mindfulness difficulties in other domains. In addition, focusedattention exercises are often contrasted to open-monitoring exercises (Lutz et al. 2008). In these exercises, participants do not focus their attention on one particular aspect of their momentary experience (e.g., their breath), but rather try to be mindfully aware of any thought, bodily sensation, and noise that they experience. Since this type of exercise is more comparable to mindfulness practice in everyday life, it seems desirable to test if a similar pattern of mindfulness difficulties would be found studying such exercises. In the present study, we chose focused-attention exercises, because openmonitoring exercises are often more difficult to understand for the lay person, and many meditation practices argue that one first needs sufficient practice in focused-attention before beginning open-monitoring meditation. A third limitation is that some of our participants with BPD suffered from comorbid anxiety disorder or comorbid bulimia nervosa. Participants’ comorbidities may have influenced their difficulties in mindfulness. For example, researcher have shown that patients who suffer from anxiety disorders have higher interoceptive accuracy (Domschke et al. 2010), a concept closely linked to mindfulness. On the other hand, it may be argued that BPD is a disorder that is characterized by frequent comorbidities (Lieb et al. 2004; Leichsenring et al. 2011) and excluding all comorbid disorders may have skewed the external validity of our findings. A fourth limitation concerns participants’ time estimates of mind-wandering. To estimate the duration of mind-wandering may be a difficult task and the subjective experience of time may not correspond to the actual duration. To simplify the task, we decided to only provide participants with three categories (1–5 s, 5–30 s, 30 or more seconds) that should be more easily distinguishable from one another. Nevertheless, our measure of length of mind-wandering remains a subjective measure and must be interpreted with caution. Lastly, some researchers argue that mind-wandering is not always maladaptive and that mind-wandering may be beneficial, for example, when task demands are low (Smallwood 2013). Individuals with BPD often experience intense emotions (Skodol et al. 2002; Linehan et al. 2007). One could speculate that mind-wandering may offer a way for individuals with BPD to cope with intense emotions. Future studies could investigate mind-wandering in BPD under different task conditions, and also assess the content of mind-wandering (e.g., see Kanske et al. 2016). Why is it so difficult for individuals with BPD to stay mindful? Several clinicians and researchers argue that individuals with BPD attempt to cope with their intense and highly unpleasant emotions (Ebner-Priemer et al. 2015) by suppressing their feelings or avoiding attention to their bodily sensations and needs (Guttman and Laporte 2002). As a consequence, individuals with BPD may have learned over time not to be mindful of their own emotions and bodily processes. In line with this theory, individuals with BPD in our study show difficulties in focusing mindfully on their breath. While the described coping strategies might have been helpful in certain situations in the past, they can become dysfunctional over time and hinder the psychotherapeutic process. To summarize, this is the first study to investigate mindfulness difficulties in BPD using a behavioral mindfulness task. We found that individuals with BPD patients mind-wandered more frequently and longer than healthy controls, while their awareness of mind-wandering was not altered. The interruption of mind-wandering (represented in awareness of mindwandering episodes in our task), is often considered the key to mindfulness practice (Grabovac et al. 2011). It may be speculated that individuals with BPD could profit from their intact awareness of mind-wandering if this was emphasized in psychotherapy. Patients’ awareness could be seen as a Bfoot in the door^ to mindfulness training, as it may help patients to Mindfulness recognize how often they are mind-wandering. Over time, if patients learn to stop mind-wandering whenever they become aware of it, they may be mindful more often. Although mindfulness exercises have already been implemented in treatment of BPD (for example: Linehan et al. 2007; Lynch et al. 2007), therapies could to a greater extent utilize exercises similar to the self-prompted mindfulness task that emphasize awareness of mind-wandering. The experimenter-prompted mindfulness task and the self-prompted mindfulness task may be used to monitor improvement of mindfulness difficulties throughout therapy. Acknowledgments The authors thank A. Stippl, S. Heinrich (Humboldt-Universität zu Berlin) and A. Daniels (Freie Universität Berlin) for assisting with participant recruitment and data collection and M. LaRue for manuscript editing. Funding The study was supported by the German Research Foundation (DFG BE 2611/2-1). Compliance with Ethical Standards Conflict of Interest The authors declare that they have no conflict of interest. References Ackenheil, M., Stotz, G., Dietz-Bauer, R., & Vossen, A. (1999). Deutsche Fassung des Mini—international neuropsychiatric interview [German version of the Mini-International Neuropsychiatric Interview]. München: Psychiatrische Universitätsklinik München. American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders (DSM4) (4th ed.). Washington, DC: American Psychiatric Association. Baer, R. A., Smith, G., & Allen, K. (2004). Assessment of mindfulness by self-report: the Kentucky inventory of mindfulness skills. Assessment, 11(3), 191–206. Bohus, M., Kleindienst, N., Limberger, M. F., Stieglitz, R. D., Domsalla, M., Chapman, A. L., & Wolf, M. (2008). The short version of the Borderline Symptom List (BSL-23): development and initial data on psychometric properties. Psychopathology, 42(1), 32–39. Brickenkamp, R. (1962). Test d2: Aufmerksamkeits-Belastungs-Test [d2 test: attention and stress test]. Göttingen: Hogrefe. Brown, K. W., & Ryan, R. M. (2003). The benefits of being present: mindfulness and its role in psychological well-being. Journal of Personality and Social Psychology, 84(4), 822–848. Buchheld, N., Grossman, P., & Walach, H. (2001). Measuring mindfulness in insight meditation (Vipassana) and meditation-based psychotherapy: the development of the Freiburg Mindfulness Inventory (FMI). Journal for Meditation and Meditation Research, 1(1), 11– 34. Burg, J. M., & Michalak, J. (2011). The healthy quality of mindful breathing: associations with rumination and depression. Cognitive Therapy and Research, 35(2), 179–185. Cárdenas-Morales, L., Fladung, A. K., Kammer, T., Schmahl, C., Plener, P. L., Connemann, B. J., & Schönfeldt-Lecuona, C. (2011). Exploring the affective component of pain perception during aversive stimulation in borderline personality disorder. Psychiatry Research, 186(2), 458–460. Choi-Kain, L. W., & Gunderson, J. G. (2008). Mentalization: ontogeny, assessment, and application in the treatment of borderline personality disorder. American Journal of Psychiatry, 165(9), 1127–1135. 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. Ebner-Priemer, U. W., Houben, M., Santangelo, P., Kleindienst, N., Tuerlinckx, F., Oravecz, Z., & Kuppens, P. (2015). Unraveling affective dysregulation in borderline personality disorder: a theoretical model and empirical evidence. Journal of Abnormal Psychology, 124(1), 186. Farb, N., Daubenmier, J., Price, C. J., Gard, T., Kerr, C., Dunn, B. D., & Mehling, W. E. (2015). Interoception, contemplative practice, and health. Frontiers in Psychology, 6(763), 1–26. Fennell, A. B., Benau, E. M., & Atchley, R. A. (2016). A single session of meditation reduces of physiological indices of anger in both experienced and novice meditators. Consciousness and Cognition, 40, 54– 66. First, M. B., Gibbon, M., & Spitzer, R. L. (1997). User’s guide for the structured clinical interview for DSM-IV axis II personality disorders: SCID-II. Arlington: American Psychiatric Publishing. First, M. B., Spitzer, R. L., Gibbon, M., & Williams, J. B. (1998). Structured clinical interview for DSM-IV axis I disorders: patient edition (February 1996 final), SCID-I/P. New York: New York State Psychiatric Institute. Fonagy, P., & Bateman, A. W. (2007). Mentalizing and borderline personality disorder. Journal of Mental Health, 16(1), 83–101. Fossati, A., Vigorelli Porro, F., Maffei, C., & Borroni, S. (2012). Are the DSM‐IV personality disorders related to mindfulness? An Italian study on clinical participants. Journal of Clinical Psychology, 68(6), 672–683. Frewen, P., Evans, E. M., Maraj, N., Dozois, D. J., & Partridge, K. (2008). Letting go: mindfulness and negative automatic thinking. Cognitive Therapy and Research, 32(6), 758–774. Frewen, P., Lundberg, E., MacKinley, J., & Wrath, A. (2011). Assessment of response to mindfulness meditation: meditation breath attention scores in association with subjective measures of state and trait mindfulness and difficulty letting go of depressive cognition. Mindfulness, 2(4), 254–269. Frewen, P., Unholzer, F., Kyle, R.-J., & MacKinley, J. D. (2014). Meditation Breath Attention Scores (MBAS): test–retest reliability and sensitivity to repeated practice. Mindfulness, 5(2), 161–169. Grabovac, A. D., Lau, M. A., & Willett, B. R. (2011). Mechanisms of mindfulness: a Buddhist psychological model. Mindfulness, 2(3), 154–166. Grossman, P. (2008). On measuring mindfulness in psychosomatic and psychological research. Journal of Psychosomatic Research, 64(4), 405–408. Guttman, H., & Laporte, L. (2002). Alexithymia, empathy, and psychological symptoms in a family context. Comprehensive Psychiatry, 43(6), 448–455. Hart, N., McGowan, J., Minati, L., & Critchley, H. D. (2013). Emotion regulation and bodily sensation: interoceptive awareness is intact in borderline personality disorder. Journal of Personality Disorders, 27(4), 506–518. Hasenkamp, W., Wilson-Mendenhall, C. D., Duncan, E., & Barsalou, L. W. (2012). Mind wandering and attention during focused meditation: a fine-grained temporal analysis of fluctuating cognitive states. NeuroImage, 59(1), 750–760. Hayes, S. C., Strosahl, K. D., & Wilson, K. G. (1999). Acceptance and commitment therapy: an experiential approach to behavior change. New York: Guilford Press. Mindfulness Hayes, S. C., Luoma, J. B., Bond, F. W., Masuda, A., & Lillis, J. (2006). Acceptance and commitment therapy: model, processes and outcomes. Behaviour Research and Therapy, 44(1), 1–25. Johnson, S., Gur, R. M., David, Z., & Currier, E. (2015). One-session mindfulness meditation: a randomized controlled study of effects on cognition and mood. Mindfulness, 6(1), 88–98. Kabat-Zinn, J. (1994). Wherever you go, there you are: mindfulness meditation in everyday life. New York: Hyperion. Kanske, P., Schulze, L., Dziobek, I., Scheibner, H., Roepke, S., & Singer, T. (2016). The wandering mind in borderline personality disorder: instability in self- and other-related thoughts. Psychiatry Research, 242, 302–310. Killingsworth, M. A., & Gilbert, D. T. (2010). A wandering mind is an unhappy mind. Science, 330(6006), 932. Leichsenring, F., Leibing, E., Kruse, J., New, A. S., & Leweke, F. (2011). Borderline personality disorder. Lancet, 377(9759), 74–84. Lieb, K., Zanarini, M. C., Schmahl, C., Linehan, M. M., & Bohus, M. (2004). Borderline personality disorder. Lancet, 364(9432), 453– 461. Linehan, M. M. (1993). Skills training manual for treating borderline personality disorder. New York: Guildford Press. Linehan, M. M. (1994). Acceptance and change: the central dialectic in psychotherapy. In S. C. Hayes, N. S. Jacobson, V. M. Follette, & M. J. Dougher (Eds.), Acceptance and change: content and context in psychotherapy (pp. 73–86). Reno: Context Press. Linehan, M. M., Bohus, M., & Lynch, T. R. (2007). Dialectical behavior therapy for pervasive emotion dysregulation. In J. Gross (Ed.), Handbook of emotion regulation (pp. 581–605). New York: Guilford Press. Lutz, A., Slagter, H. A., Dunne, J. D., & Davidson, R. J. (2008). Attention regulation and monitoring in meditation. Trends in Cognitive Sciences, 12(4), 163–169. Lynch, T. R., Trost, W. T., Salsman, N., & Linehan, M. M. (2007). Dialectical behavior therapy for borderline personality disorder. Annual Review of Clinical Psychology, 3, 181–205. Michalak, J., Heidenreich, T., Ströhle, G., & Nachtigall, C. (2008). Die deutsche Version der mindful attention and awareness scale (MAAS): psychometrische Befunde zu einem Achtsamkeitsfragebogen [The German version of the mindful attention and awareness scale (MAAS): psychometric findings of a mindfulness questionnaire]. Zeitschrift für Klinische Psychologie und Psychotherapie; Forschung und Praxis, 37(3), 200–208. Montgomery, S. A., & Asberg, M. (1979). A new depression scale designed to be sensitive to change. British Journal of Psychiatry, 134(4), 382–389. Pavony, M. T., & Lenzenweger, M. F. (2013). Somatosensory processing and borderline personality disorder features: a signal detection analysis of proprioception and exteroceptive sensitivity. Journal of Personality Disorders, 27(2), 208–221. Prätzlich, M., Kossowsky, J., Gaab, J., & Krummenacher, P. (2016). Impact of short-term meditation and expectation on executive brain functions. Behavioural Brain Research, 297, 268–276. Sachse, S., Keville, S., & Feigenbaum, J. (2011). A feasibility study of mindfulness‐based cognitive therapy for individuals with borderline personality disorder. Psychology and Psychotherapy, 84(2), 184– 200. Sauer, S., Walach, H., Schmidt, S., Hinterberger, T., Lynch, S., Büssing, A., & Kohls, N. (2013). Assessment of mindfulness: review on state of the art. Mindfulness, 4(1), 3–17. Schmidt, K.-H., & Metzler, P. (1992). Wortschatztest: WST [Wording test: WST]. Weinheim: Beltz. Sheehan, D. V., Lecrubier, Y., Sheehan, K. H., Amorim, P., Janavs, J., Weiller, E., & Dunbar, G. C. (1998). The mini-international neuropsychiatric interview (MINI): the development and validation of a structured diagnostic psychiatric interview for DSM-IVand ICD-10. Journal of Clinical Psychiatry, 59, 22–33. Skodol, A. E., Gunderson, J. G., Pfohl, B., Widiger, T. A., Livesley, W. J., & Siever, L. J. (2002). The borderline diagnosis I: psychopathology, comorbidity, and personality structure. Biological Psychiatry, 51(12), 936–950. Smalley, S. L., Loo, S. K., Hale, T. S., Shrestha, A., McGough, J., Flook, L., & Reise, S. (2009). Mindfulness and attention deficit hyperactivity disorder. Journal of Clinical Psychology, 65(10), 1087–1098. Smallwood, J. (2013). Distinguishing how from why the mind wanders: a process–occurrence framework for self-generated mental activity. Psychological Bulletin, 139(3), 519. Soler, J., Valdepérez, A., Feliu-Soler, A., Pascual, J. C., Portella, M. J., Martín-Blanco, A., & Pérez, V. (2012). Effects of the dialectical behavioral therapy-mindfulness module on attention in patients with borderline personality disorder. Behaviour Research and Therapy, 50(2), 150–157. Wagner, T., Roepke, S., Marschall, P., Stiglmayr, C., Renneberg, B., Gieb, D., & Fydrich, T. (2015). Krankheitskosten der Borderline Persönlichkeitsstörung aus gesellschaftlicher Perspektive [Medical expenses of borderline personality disorder from a societal perspective]. Zeitschrift für Klinische Psychologie und Psychotherapie, 42(4), 242–255. Walach, H., Buchheld, N., Buttenmüller, V., Kleinknecht, N., & Schmidt, S. (2006). Measuring mindfulness—the Freiburg mindfulness inventory (FMI). Personality and Individual Differences, 40(8), 1543–1555. Welch, S. S., Rizvi, S., & Dimidjian, S. (2006). Mindfulness in dialectical behavior therapy (DBT) for borderline personality disorder. In R. A. Baer (Ed.), Mindfulness-based treatment approaches: clinician’s guide to evidence base and applications (pp. 117–139). London: Elsevier Academic Press. Williams, J. M. G. (2008). Mindfulness, depression and modes of mind. Cognitive Therapy and Research, 32(6), 721–733. Williams, J. M. G., & Swales, M. (2004). The use of mindfulness-based approaches for suicidal patients. Archives of Suicide Research, 8(4), 315–329. Wittchen, H.-U., Zaudig, M., & Fydrich, T. (1997). Strukturiertes klinisches Interview für DSM-IV (SKID-I und SKID-II) [structured clinical interview for DSM-IV (SKID-I and SKID-II). Göttingen: Hogrefe. Wupperman, P., Neumann, C. S., & Axelrod, S. R. (2008). Do deficits in mindfulness underlie borderline personality features and core difficulties? Journal of Personality Disorders, 22(5), 466–482. Wupperman, P., Neumann, C. S., Whitman, J. B., & Axelrod, S. R. (2009). The role of mindfulness in borderline personality disorder features. Journal of Nervous and Mental Disease, 197(10), 766– 771. Wupperman, P., Fickling, M., Klemanski, D. H., Berking, M., & Whitman, J. B. (2013). Borderline personality features and harmful dysregulated behavior: the mediational effect of mindfulness. Journal of Clinical Psychology, 69(9), 903–911. Zanarini, M. C., Frankenburg, F. R., Hennen, J., & Silk, K. R. (2003). The longitudinal course of borderline psychopathology: 6-year prospective follow-up of the phenomenology of borderline personality disorder. American Journal of Psychiatry, 160(2), 274–283.