The Inner Void: Study Probes How Emptiness Drives Self-Destruction in Borderline Personality Disorder

Chronic feelings of emptiness have long been described by people with borderline personality disorder as one of the most agonizing and least understood features of their condition. Unlike sadness or anxiety, emptiness is not a sharp emotion but an aching absence, an inner void marked by disconnection from oneself and others and a pervasive lack of fulfillment. It is written directly into the diagnostic criteria for borderline personality disorder, yet it has received far less scientific attention than the disorder’s more visible symptoms, such as self-harm, suicidal behavior, and unstable relationships. A new controlled study published in BMC Psychology by Leeav Sheena-Peer, Yogev Kivity, and colleagues at Bar-Ilan University in Israel set out to change that, asking a deceptively simple question: what happens when the inner void becomes unbearable, and does the capacity to understand mental states protect people from turning that void into harmful action?

The research team recruited three carefully matched groups of adults, with fifty-one participants in each: individuals diagnosed with borderline personality disorder, psychiatric controls who experienced other mental health difficulties, and healthy controls with no psychiatric diagnosis. This three-group design is critical, because it allows researchers to distinguish what is specific to borderline personality disorder from what is shared across forms of psychological distress. Many symptoms once considered hallmark features of the disorder, including impulsivity and self-injury, turn out to be elevated in other clinical populations as well. By comparing all three groups on the same measures, the study could determine whether emptiness and its behavioral consequences truly set borderline personality disorder apart, or whether they represent a more general phenomenon of psychological suffering.

Methodologically, the study went beyond simple questionnaires. Participants completed the Subjective Emptiness Scale, a validated instrument measuring the depth and persistence of inner void experiences, along with a newly developed inventory assessing self-destructive behaviors that occur specifically in response to feelings of emptiness. This novel measure is an important technical advance, because prior research often conflated self-destructive acts driven by many different triggers. By asking participants to report harmful behaviors that follow emptiness episodes in particular, the researchers could isolate the pathway from the inner void to harmful action rather than measuring a general tendency toward self-harm that might stem from anger, shame, or other emotional states entirely.

The study’s most ambitious component involved measuring mentalizing, the capacity to understand behavior, both one’s own and that of others, in terms of underlying mental states such as thoughts, feelings, desires, and intentions. Mentalizing has become one of the most influential constructs in contemporary theories of borderline personality disorder, and mentalization-based treatment is a widely used therapeutic approach built on the idea that improving this capacity reduces symptoms. Participants completed two separate interviews coded with the Reflective Functioning Scale, a gold-standard scoring system in the field. The first interview assessed general mentalizing about relationships and life experiences. The second was a novel emptiness-focused interview, designed to capture what the researchers call emptiness-specific mentalizing: the ability to make sense of the experience of inner void itself, to reflect on what emptiness feels like, where it comes from, and what it means.

The results confirmed the centrality of emptiness in the disorder. Individuals with borderline personality disorder reported significantly greater emptiness than both psychiatric controls and healthy controls, and they also reported more self-destructive behaviors overall and more self-destructive behaviors specifically following episodes of emptiness. This pattern held even when compared against other people receiving mental health care, strengthening the argument that emptiness is not merely a nonspecific symptom of general distress but a distinctive and clinically significant feature of borderline personality disorder. For clinicians, the finding reinforces what many patients describe anecdotally: the void is not a side note to the disorder but one of its core, driving experiences.

Yet the study also produced a genuinely surprising result. Despite the theoretical prominence of mentalizing in models of borderline personality disorder, the BPD group did not differ from the comparison groups in either general mentalizing or emptiness-specific mentalizing as assessed in these retrospective interviews. This finding challenges a straightforward version of the mentalizing deficit hypothesis, at least as it applies to this population and this measurement approach. It suggests that when people with borderline personality disorder are interviewed in a structured, reflective setting about their experiences, their capacity to describe mental states may be comparable to that of other adults, including healthy ones. Deficits, if they exist, may be more state-dependent, emerging under emotional arousal or in interpersonal situations rather than in calm, retrospective reflection.

The central hypothesis of the study concerned moderation: the researchers predicted that stronger mentalizing would buffer the link between emptiness and self-destructive behavior, so that people who could make sense of their inner void would be less likely to act on it destructively. Across all three groups, emptiness did predict self-destructive behaviors, confirming the intuitive and clinically important association between the inner void and harmful action. However, neither group membership nor mentalizing moderated this association. In other words, the relationship between feeling empty and acting destructively held its strength regardless of how well participants could reflect on mental states in the interviews, and this pattern was consistent across people with borderline personality disorder, other psychiatric patients, and healthy controls.

This null moderation result carries real theoretical weight. It suggests that retrospective mentalizing, the reflective capacity measured in interview settings, may not be the protective factor that some clinical theories would predict. Several explanations are possible, and the authors are careful to frame the finding as an invitation for further research rather than a definitive refutation. Mentalizing may need to be measured in the moment, during an actual emptiness episode, to capture its protective potential; the ability to reflect calmly after the fact may not translate into the capacity to regulate oneself in the heat of an agonizing void. Alternatively, the specific form of mentalizing that matters may differ from what the Reflective Functioning Scale captures, or the sample size of fifty-one per group may have limited statistical power to detect a moderation effect of modest size. It is also possible that the link between emptiness and self-destruction is so direct and visceral that reflective understanding alone cannot interrupt it.

The cross-group consistency of the emptiness-to-harm pathway is arguably the study’s most broadly significant contribution. Emptiness predicted self-destructive behaviors not only in people with borderline personality disorder but across all participants, including healthy adults. This suggests that the inner void is a transdiagnostic risk factor, a dimension of human experience that can push anyone toward harmful action when it becomes severe enough. That framing has implications well beyond one diagnosis. Screening for emptiness in psychiatric assessment, regardless of the presenting diagnosis, may help identify individuals at risk for self-harm who would otherwise be missed by symptom checklists focused on mood or anxiety. It also resonates with a growing body of work on loneliness, meaninglessness, and disconnection as fundamental drivers of psychological suffering in modern life.

For the field of borderline personality disorder research, the study marks an important step toward treating emptiness as a legitimate scientific object rather than a vague clinical impression. The development of an emptiness-specific mentalizing interview and a targeted inventory of emptiness-driven self-destructive behavior gives researchers new tools to dissect the pathway from inner void to harmful action. Future work, the findings imply, should examine mentalizing in real time, test whether interventions that target emptiness directly, rather than the disorder as a whole, can reduce self-destructive behavior, and explore whether other capacities, such as emotion regulation or self-continuity, might serve as the true buffers between void and action. What is already clear is that the aching absence so many patients struggle to describe deserves a central place in both research and treatment, and that understanding it may be one of the keys to preventing some of the most dangerous consequences of psychological pain.

Subject of Research: The relationship between chronic emptiness, self-destructive behaviors, and mentalizing capacity in borderline personality disorder

Article Title: From inner void to harmful action: a controlled study of emptiness, self-destructive behaviors, and mentalizing in borderline personality disorder

Article References: From inner void to harmful action: a controlled study of emptiness, self-destructive behaviors, and mentalizing in borderline personality disorder. (n.d.). https://doi.org/10.1186/s40359-026-05687-9

Image Credits: AI Generated

DOI: 10.1186/s40359-026-05687-9

Keywords: borderline personality disorder, emptiness, mentalizing, self-destructive behavior, reflective functioning, psychiatric controls, transdiagnostic, inner void, self-harm, BMC Psychology, Bar-Ilan University, clinical psychology