Biofeedback and Treatment for Borderline Personality Disorder

Borderline personality disorder is associated with major morbidity and mortality. Existing studies estimate that the disorder occurs in 1%–3% of the general population (1, 2), representing 9%–18% of psychiatric outpatient populations and 15%–22% of psychiatric inpatient populations (3–5). The disorder is defined by dysregulation across emotional, behavioral, interpersonal, and cognitive realms, and an underdeveloped sense of self. As a result, people with the disorder have difficulty navigating and functioning in their personal and professional lives, often depending on self-harm behaviors to communicate their distress or to regulate their emotions. In more severe presentations, these maladaptive behaviors may limit the individual’s capacity to maintain stability in their relationships and jobs. Borderline personality disorder, therefore, constitutes a material source of long-term disability in both interpersonal and vocational realms (6) and is associated with high use of costly mental health services (7).

Despite the high rates of disability in this population, there is growing evidence that the disorder can be successfully treated, especially with empirically validated therapies. Two large NIMH-funded prospective studies on the course and outcome of borderline personality disorder (8–10) found unexpectedly high remission rates with treatment across 10 and 16 years, respectively, although full recovery was harder to achieve. One way to improve long-term recovery rates is to rely on empirically validated treatments that have demonstrated treatment efficacy in randomized controlled trials. These treatments include dialectical behavioral therapy (DBT) (11, 12), transference-focused psychotherapy (TFP) (13), and mentalization-based treatment (MBT) (14). Each of these treatments conceptualizes borderline personality disorder somewhat differently, with approaches ranging from a psychodynamic to a cognitive-behavioral skills-based framework. Although these therapeutic modalities constitute different theoretical and practical applications, they all share the goal of increasing structured self-assessment to promote emotional regulation.

Accurate self-assessment of emotions at minimum requires evaluation of two concurrent internal experiences: assessment of one’s physiology and assessment of the associated cognitive appraisal of that physiology. As Linehan (11, 12) has aptly described, valid labeling of emotions requires accurate evaluation of both physiology and cognitive appraisals of these internal experiences. The physiological changes that come along with emotions happen regardless of our awareness of them, so noting these changes becomes a crucial opportunity for intervention. Individuals who learn to specifically identify the emotion they are experiencing through accurate self-assessment can process emotions and communicate more effectively (11, 12). One way to help individuals accurately assess emotions is to measure the physiological correlates of these internal experiences with an electronic instrument, a method referred to as biofeedback. In this article, we aim to add to the current body of literature by advocating for integration of biofeedback measures into treatment modalities for borderline personality disorder to facilitate development of self-awareness, to inform established treatments for the disorder, and to possibly offer a more cost-effective alternative to existing therapeutic interventions (15).

Below, we outline the benefits of adding biofeedback to existing empirically supported approaches. We examine how biofeedback can provide constructive benefit by exploring its utility as an adjunct to DBT, MBT, and TFP, all of which are established therapies that, to some degree, focus on emotion regulation but lack tools to accurately assess objective physiological correlates to emotional experiences. We suggest that biofeedback, by providing objective measurements, may serve as a tool for increasing structured self-assessment, thereby maximizing treatment benefits, improving remission and recovery rates, and possibly mitigating the need for longer-term, time-intensive treatments. Because biofeedback can be taught to mental health clinicians, this intervention has the potential to make effective treatment more accessible to the larger population of individuals living with borderline personality disorder.

Challenges With Structured Self-Assessment in Existing Treatments for Borderline Personality Disorder

It has been established that borderline personality disorder is the result of nature and nurture (11). The biological underpinnings associated with the disorder are becoming more widely recognized and include differences in neurological functioning. Recent evidence indicates that people with the disorder may be hard-wired to experience emotions differently than their control counterparts. For example, a recent study (16) examined the impact of emotional action control on the brain circuits of women with borderline personality disorder. Bertsch and colleagues (16) found that women with the disorder displayed altered reactivity to emotional stimuli and emotion regulation on magnetic resonance imaging of the brain when tasked with approaching happy faces and avoiding angry faces. Compared with healthy control subjects, patients with the disorder showed reduced activity in prefrontal-amygdala communication. These two areas of the brain are essential to the experience and subsequent labeling of emotions. Findings from the Bertsch et al. study suggest that, compared with control subjects, patients with borderline personality disorder have a biological vulnerability, caused by dysfunctional activation of various areas of the brain, that affects their processing and tolerating of emotions when exposed to emotional stimuli. These findings align with evidence from other neuroimaging studies (17, 18), where results have shown that emotion dysregulation of patients with borderline personality disorder is correlated with dysfunctional activation of various areas of the brain involved in emotional reactivity and planning, including the amygdala and the prefrontal cortex.

Taken together, these findings indicate that patients with borderline personality disorder have neurobiological vulnerabilities that may require specific tools to help with self-assessment and integration of treatment interventions, akin to people diagnosed with diabetes benefitting from glucose monitoring to better understand the ways that their pancreas and insulin function when encountering glucose. However, despite growing knowledge that patients with borderline personality disorder have unique challenges, there is no established standard to facilitate emotional awareness at this physiological level. Therefore, patients undergoing these empirically supported treatments for borderline personality disorder could benefit from methods to accurately assess internal experiences and the effectiveness of subsequent interventions intended to combat heightened emotions, thereby enabling them to better modulate the behavioral reactivity that often contributes to hospitalization. Assessing emotion regulation before a crisis arises requires an ability to reflect on multiple aspects of functioning, including fluctuating cognitive and emotional states.

In TFP, a psychodynamic therapy that is based on object relations theory, the therapy focuses on the clinician’s ability to help patients clarify and confront their rigid psychological organization by identifying their conflicts about their sense of self in relation to their world, in order to encourage integration of a more nuanced and realistic understanding of self and others. One strategy to help increase self-awareness is through intensive twice-weekly therapy by a trained expert who can help track and highlight internal conflicts that otherwise might remain outside of conscious awareness and continue to wreak havoc on the patient’s world. In the United States, TFP is an expensive, twice-weekly, long-term commitment, often requiring 3 years of intensive therapy with a trained expert. Although established as an effective treatment for borderline personality disorder, TFP lacks integration of an objective measure to assess emotions. Such a measure might be used to promote and enhance self-awareness, at least at the physiological level, and integration of effective regulation strategies. Thus, although effective, TFP has several limitations, especially as an accessible treatment for the masses.

MBT is also effective, and like TFP, it focuses on the ways in which individuals understand themselves and their role in their world. TFP differs from MBT in that it integrates different methods to achieve a similar goal. Among several key interventions, the power of being curious about what might be in someone else’s mind, is central in MBT. In this treatment modality, assuming an uncertain stance allows for curiosity and promotes the notion that other people may not think and feel the same way. The MBT stance allows for a broader, more flexible understanding of oneself and one’s relationships. Although this concept may sound simple, it is complicated when people are not accustomed to self-reflecting and examining multiple perspectives of the same interaction when distressed. MBT experts report that a diagnosis of borderline personality disorder can be linked to early experience in which curiosity was deprioritized (14). For example, a caregiver may have mirrored crying in response to a tearful child, or problem solving in response to high emotion, rather than promoting curiosity by frowning in reaction to the child’s emotion and then making a statement about how the caregiver imagines the child may be feeling. The latter action, called a marked and contingent response, is something that is often helpful for parents to learn how to do, because it allows the child to not only feel validated but also to develop comprehension of the relationship between actions, mental states, and interpersonal interactions. MBT treatment, although effective, is also quite costly, and many of the treatment components are not easily covered by insurance in the United States. MBT requires once-weekly individual treatment by a trained expert as well as weekly group therapy. Similar to TFP, this orientation also lacks integration of an objective tool to facilitate increased awareness of internal states and is also a costly, long-term endeavor.

In DBT, which is based on a biosocial theory of borderline personality disorder etiology and implicates a biological predisposition to emotional vulnerability and reactivity and an invalidating environment in the development of the disorder, the goal is to develop effective skills-based interventions to promote self-awareness of emotions and subsequent self-regulation. The transactional relationship between genes and environment leads to a history of difficulties learning about, labeling, expressing, and modulating emotions that often culminates in problems related to self-harm and suicidality, as well as difficulty expressing or regulating emotions (11, 12). One way that self-awareness is achieved in DBT is through chain analysis, a method requiring identification of vulnerability factors along with the triggering event and behavioral and cognitive factors that affect subsequent difficulties. Although these tools enhance self-assessment, they rely on subjective approaches for evaluation. DBT also incorporates skills-based groups and worksheets to help individuals not only increase their self-awareness but also to integrate skill-based regulatory techniques to manage their emotions. DBT is perhaps the most well-established treatment for borderline personality disorder, but it is also expensive. The treatment requires 2 years of weekly therapy plus a skills group, both administered by an expert trained in DBT. However, although DBT is skills based and promotes self-awareness, no standard and objective measure has been integrated into the existing treatment to promote self-awareness of emotions. Much like TFP and MBT, DBT is a long-term, time-intensive, and costly treatment (11, 12).

Regardless of the treatment modality, a central aim across these therapies is to increase awareness of one’s own internal states and to develop a capacity to self-regulate, but none of these therapies have established objective measures toward achieving this goal. Without the capacity to initially assess internal states when experiencing more nuanced emotions, individuals with borderline personality disorder can become overstimulated or remain numb in the face of emotional stimuli. Many describe feeling detached from their emotions or overwhelmed by their intensity, and both situations present challenges to applying effective interventions, such as mindfulness. These overstimulated states also minimize opportunities for self-reflection or meta cognition because the prefrontal cortex shuts down in the face of high emotionality. In extreme moments of distress, people may feel dissociated or disconnected from their thoughts and behaviors, impairing their ability to accurately self-assess and to acknowledge the need to apply skills-based interventions. Similarly, individuals can become overwhelmed by their emotions, and lose the capacity to think clearly and to skillfully intervene, instead of reverting to impulsive behaviors. This lack of awareness of one’s own emotional barometer often leads to reinforcement of maladaptive and problematic behaviors, such as drinking or overmedicating in response to intense feelings.

It is possible to teach self-assessment and self-regulation by examining the physiological aspects of emotions, thereby giving individuals an opportunity to learn to identify and regulate by attending to and mastering awareness of the biological correlates associated with emotional experiences. All emotions have unique biological correlates that can be measured through physiological parameters. For example, jealousy is associated with an increased heart rate, clenched teeth, tensed muscles, and a change in breathing rate (12). Lack of emotional self-awareness affects one’s ability to recognize these cues and to subsequently apply interventions that could effectively modulate the emotion. Furthermore, increasing self-awareness may be a prerequisite for using established treatment interventions, such as mindfulness. Thus, we propose that individuals with borderline personality disorder would benefit from learning concrete strategies to increase their structured self-assessment of the mind-body connection. By exploring biological correlates associated with emotional stimuli, individuals could be taught to recognize bodily responses in the autonomic nervous system (ANS) and to address emotions before becoming overstimulated or numb.

A key benefit that biofeedback can add to existing empirically supported treatments, as either an adjunctive or possibly a stand-alone treatment, is an objective measure of emotion regulation as assessed by one’s own biological correlates of physiologic arousal. Current treatments (TFP, MBT, and DBT) promote this process only subjectively. Access to an objective measure of self-assessment could be particularly beneficial within the borderline personality disorder population, given this population’s difficulties in identifying nuances in internal experiences, mislabeling their emotions, and misevaluating the impact of interventions. Biofeedback provides an opportunity for enhanced awareness, through undeniable concrete feedback, of one’s developing mastery in applying intentional skillful interventions. The objective nature of the feedback is particularly relevant in this population, where all-or-none thinking is a hallmark feature of the diagnosis, and therefore there is a propensity to otherwise discount incremental progress.

Biofeedback as a Self-Assessment Tool and Intervention

Heightened interest in the mind-body link since the mid-1960s, followed by subsequent evidence that the ANS could be consciously controlled by the human mind, together established one of the first empirical indicators of the nature of the relationship between mind and body (19). The ANS controls regulatory functions, such as heart rate, respiration, and skin conductance. It is composed of the parasympathetic nervous system, which is involved in the relaxation response, and the sympathetic nervous system, which is implicated in the fight-or-flight response. These responses are instrumental in the survival of the fittest tenet of Darwinian theory because they prepare the body to fight or flee in the face of danger. According to this theory, individuals with well-honed fight-or-flight systems are better equipped to respond to (and more likely to survive in) dangerous situations.

Recent theories on emotion implicate the ANS in developing and maintaining many emotional disorders, including mood and anxiety disorders. For example, Barlow and Craske (20) developed a theory of panic disorder. They attributed the development and maintenance of panic disorder and panic attacks to misinterpretations of the physiological responses associated with the fight-or-flight response. From this theory, Craske and Barlow (21) subsequently developed and tested a structured treatment approach for patients with panic disorder. A vital component of this treatment is helping individuals who have panic disorder to increase their awareness and knowledge of the functions of both systems within the ANS. The therapy teaches individuals to attend to various physiological responses to their anxiety, such as noticing shifts in their breathing patterns. Sometimes the therapy requires the therapist to induce shifts in the individual’s breathing in session, to expose the individual to the often feared, and hence avoided, physiological response. It is through this exposure that individuals become aware of the body’s responses to panic and subsequently learn effective ways to manage the fight-or-flight response system, including interventions that stimulate the parasympathetic nervous system, which enables a relaxation response.

Whereas recent theories implicate the ANS in the development and maintenance of mood and anxiety disorders, the early work of Edmund Jacobson (22) pioneered the linking of physiological correlates to the development and treatment of high emotional arousal. He introduced the concept of progressive muscle relaxation, a technique in which intentional regulation of one’s physiology is used to calm oneself, thereby laying the foundation for biofeedback as a means of regulating emotional states. Jacobson proposed that muscle tension accompanies anxiety, and anxiety could therefore be reduced by learned methods of relaxing muscle tension. Progressive muscle relaxation involves voluntarily tensing and sequentially relaxing muscles to achieve greater relaxation, thereby decreasing anxiety (22, 23). Biofeedback is the method of measuring the effectiveness of the relaxation intervention and functions by providing the individual with objective feedback on the physiological aspects of emotions, such as muscle tension, following intentional efforts to regulate one’s emotions. Biofeedback has been shown effective in treating several general medical health conditions, including hypertension, urinary and fecal incontinence, headaches, diabetes, epilepsy, and cardiac arrhythmias (19), as well as numerous psychiatric disorders, such as attention-deficit hyperactivity disorder (24), generalized anxiety disorder (25), panic disorder (26), obsessive-compulsive disorder (27), sleep disorders (28), and anorexia (29).

Biofeedback allows individuals to track their ANS responses in conjunction with instruction in how to control these processes. Electromechanical instruments are used to measure and give accurate feedback to patients, with the purpose of reinforcing beneficial physiological processes (19). Through repeated use of biofeedback, individuals learn about the biological correlates (often dictated by the ANS) associated with different emotional states and gain conscious awareness, and ultimately some control over, their physiological response systems (19). An initial step for the counselor in applying biofeedback is to help individuals cultivate an increased self-awareness of their physiological responses when emotionally aroused. A range of biofeedback tools can be used to assess heart rate, muscle tension, skin conductance, and several other physiological markers of ANS functioning. Although experts in the field use highly specialized tools, there are emerging technologies to provide adequate alternative physiological markers of the ANS that can be evaluated and assessed both in and out of formal therapy sessions to not only facilitate awareness, but also to allow individuals to assess the accuracy and effectiveness of their intentional interventions to activate the parasympathetic nervous system (i.e., the rest-and-digest system).

By evaluating physiological functioning with objective measures, individuals receive concrete information about bodily responses correlated with states of emotional arousal or relaxation and can learn how to focus on and modify signals from their bodies. Biofeedback, together with progressive muscle relaxation, diaphragmatic breathing, visual imagery, and other stress-reducing techniques, can enable individuals to recognize when their bodies are in a state of relaxation. To effectively apply biofeedback techniques, individuals use visual and audio feedback to increase self-awareness of bodily states and to learn strategies for altering their physiological correlates in response to these bodily cues. For example, if an individual with debilitating tension headaches learns that body temperature decreases as muscle tension increases, biofeedback can be used to train the person to warm the body in order to control or contain the tension headache before it becomes unmanageable. This training occurs by introducing different relaxation methods and by assessing the effectiveness of each intervention through physiological markers, such as body temperature. Once the individual masters the technique of warming the body, which can be taught by using a range of biofeedback techniques, the skill can be applied independently of biofeedback tools.

Case Example

In this case example, a 22-year-old single Caucasian female, Jane, sought treatment for worsening depression, anxiety, substance use, and self-harm. She was referred for treatment in response to her parent’s request; they feared for her safety because of her increased reports of suicidal ideation following a breakup with her partner. During the initial meeting, Jane shared her declining functioning, reporting she had recently stopped attending school and was failing her classes. Her current academic standing was further damaging her self-esteem and exacerbating her fear of failure. She found herself in a constant state of “paralysis,” felt “numb,” was unable to label her emotions or regulate her feelings, and was surviving by isolating in her dorm room in an almost catatonic and desperate state. She felt out of control and untethered. She was sure she was incapable of improving her life and had little hope, which compromised her motivation to actively engage in treatment. Given Jane’s overwhelming emotional overload and subsequent hopeless and helpless orientation, biofeedback was introduced as an initial intervention. The priority was to help her develop some modicum of agency that was undeniable, hence she was provided with objective data on her improvement during the process of change. During the first few sessions, Jane was given a stress thermometer to measure her temperature from the index finger, a proxy of ANS activity. Higher temperatures indicate parasympathetic activity activation (rest-and-digest system), whereas lower temperatures indicate sympathetic system activation (fight-or-flight system). Jane was introduced to a range of various stress-inducing activities during therapy sessions (thinking or talking about an emotionally activating event, engaging in 3 minutes of rigorous exercise, attempting to solve math problems) and was taught about the associated objective markers (via body temperature) that were affiliated with these stressful activities. Jane was introduced to a series of distress tolerance and emotion regulation interventions (autogenic training, imagery, progressive muscle relaxation, diaphragmatic breathing) to activate her parasympathetic nervous system. She was then taught the associated objective markers (via her temperature) that were affiliated with these relaxation interventions. She was asked to use her thermometer each day and to practice the regulation strategies on her own, which she reported not only helped her in her own self-awareness of her physiological arousal, via the objective biofeedback marker of temperature, but also provided her with a sense of mastery over her emotion regulation capacity. She learned to regulate her parasympathetic system and reported an enhanced sense of control and clarity. Her report of her own feelings of mastery and agency in responding to bouts of intense anxiety improved over the ensuing weeks, which unsurprisingly, influenced her assessment of her depression. Although her underlying conflicts around dependency remained and required additional work, her functioning had drastically improved, along with her feelings of hope.

Discussion

Recent studies have focused on the potential to apply biofeedback techniques to the treatment of borderline personality disorder. In 2017, Carr et al. (30) found a significant relationship between low heart rate variability and negative mood in participants with borderline personality disorder, suggesting a decrease in parasympathetic activation and an increase in heart rate with negative moods. Biofeedback measurements, accessible through wearable devices and smartphones, can capture such mood variation objectively and consistently. By using such tools, individuals with borderline personality disorder can learn how their bodies respond to various stress-inducing conditions, such as distressful situations, pain, and tension, thereby increasing the capacity to identify when they are experiencing distress.

The work of Carr et al. (30) is one example of a growing body of evidence that demonstrates a measurable relationship between emotions and biological correlates of individuals with borderline personality disorder. Increased self-awareness, and the subsequent enhanced control of bodily states through cognitive and behavioral interventions, is a critical component of treatment for most emotional disorders. As a result, self-awareness is particularly important in treating borderline personality disorder. Without self-awareness, individuals with borderline personality disorder cannot use skills, such as mindfulness, emotion regulation, curiosity, or basic self-reflective interventions, to modulate their cognitive and behavioral responses to emotional stimuli. Although biofeedback has been proven to treat other emotional disorders, and despite an increase in recent studies on biofeedback and borderline personality disorder, to our knowledge, no research has specifically examined the efficacy of systematically integrating biofeedback into existing treatment for borderline personality disorder. For example, research has shown (19) that biofeedback improves understanding and early detection of states of emotional arousal among children with anger and impulse-control problems, thereby enhancing children’s ability to put time and space between impulse and action and to make more appropriate behavioral decisions. It seems likely biofeedback would have similar utility for individuals with borderline personality disorder. For example, if an individual with borderline personality disorder learns, by using a biofeedback tool, that his or her heart rate increases when he or she starts to become anxious, the individual could use biofeedback to identify and practice specific behavioral techniques to decrease the heart rate before the anxiety becomes unmanageable.

Conclusions

Biofeedback offers the potential to help increase self-awareness of emotional states. In conjunction with instruction in how to effectively influence ANS processes, biofeedback can be used to improve an individual’s ability to identify, contain, and manage distress. For example, when an increase in heart rate is observed, rather than waiting until the emotion is so intense that the individual becomes overwhelmed and engages in self-harm or other self-defeating behaviors to escape the experience, the patient can apply effective interventions. The application of biofeedback for patients with borderline personality disorder is particularly compatible with the model of emotions outlined in DBT, which conceptualizes emotions as full body-and-mind experiences involving bodily changes; brain changes; action urges; interpretations, beliefs, and assumptions; verbal and nonverbal expression; and applied labels (giving a name to the emotion) (31). Biofeedback, however, can be integrated across a host of empirically supported borderline personality disorder treatments, including TFP and MBT. For example, in MBT, getting one’s thinking “back online” enhances clarity of self-assessment, and biofeedback could only facilitate the process and accuracy of mentalization. As such, biofeedback could improve existing treatments, such as MBT, by enhancing emotion regulation and self-assessment, thereby providing a window to more accurately approximate what is in someone else’s mind.

Biofeedback techniques could be used to help individuals with borderline personality disorder learn to detect escalating emotions early and then to regulate the physiological correlates of the distressing emotional and cognitive experiences, thus improving self-awareness and emotion regulation. Further empirical investigation into the ways in which biofeedback can improve the panoply of borderline personality disorder symptoms would be beneficial. Not only does biofeedback improve self-awareness of emotions and empower agency toward change on the basis of undeniable objective assessments, biofeedback techniques appear to improve sense of mastery, hope, and capacity—aspects of the sense of self that are targeted in the treatment of borderline personality disorder. Additionally, given the interpersonal effects of borderline personality disorder, it is central to support the patient’s growing autonomy and independence—two areas that are prioritized in biofeedback and which serve to preserve relationships (by not depleting interpersonal resources by overreliance on others during times of high stress). Therefore, biofeedback holds promise as an effective, low-cost adjunct to existing treatments and may even prove to be a stand-alone intervention for helping individuals with borderline personality disorder, perhaps mitigating the need for more intensive, longer-term therapies.