Source: Abnormal Psychology, University of Florida

Tags: Cluster B, dramatic-emotional, borderline personality disorder, BPD, histrionic personality disorder, narcissistic personality disorder, antisocial personality disorder, ASPD, dialectical behaviour therapy, DBT, splitting, mentalization, transference-focused therapy

Difficulty: Intermediate | Prerequisites: Part 1 of these notes (general personality disorder criteria and the DSM-5 framework). Familiarity with mood disorders is helpful for understanding borderline's overlap with depression.

Big Picture

Cluster B is where the highest-stakes clinical material lives. These four disorders, antisocial, borderline, histrionic and narcissistic, share a common thread of unstable emotions, dramatic or impulsive behaviour, and troubled interpersonal relationships. Borderline personality disorder receives the most research attention (and the most exam questions) because of its complexity, high comorbidity and association with suicide. Antisocial personality disorder has a unique diagnostic rule you need to know: it is the only personality disorder that cannot be diagnosed before age 18. If you are short on revision time, prioritise borderline and its treatments.

TL;DR

Cluster B personality disorders are characterised by dramatic, erratic or emotionally volatile behaviour. Borderline personality disorder involves instability in mood, self-image and relationships, with high rates of self-harm and suicide. Histrionic personality disorder centres on attention-seeking and shallow emotional expression. Narcissistic personality disorder is defined by grandiosity, need for admiration and lack of empathy. Antisocial personality disorder involves disregard for others' rights, deceitfulness and lack of remorse.

Key Terms

Antisocial personality disorder (ASPD)

A pattern of disregard for and violation of the rights of others, including criminal, impulsive, deceitful or callous behaviour and a lack of remorse. In simple terms, this is the person who repeatedly breaks rules and hurts others without feeling guilty about it. Must show evidence of conduct disorder by age 15.

Borderline personality disorder (BPD)

A pattern of instability in self-image, mood and interpersonal relationships, marked impulsivity, transient dissociative states, and extreme reactivity to real or imagined abandonment. Think of it as emotional life on a hair trigger, where the person swings between idealising and despising the same person, struggles to regulate any strong feeling, and may hurt themselves in the process.

Histrionic personality disorder

A pattern of excessive emotionality and attention-seeking, with dramatic, seductive or provocative behaviour, high suggestibility, and shallow emotional expression and relationships. In simple terms, the person who always needs to be the centre of attention and whose emotional displays feel performative rather than deep.

Narcissistic personality disorder (NPD)

A pattern of grandiosity, need for admiration and lack of empathy, with entitled, arrogant and exploitative attitudes. Think of it as the person who believes they are fundamentally superior and treats others accordingly.

Dialectical behaviour therapy (DBT)

A treatment developed for borderline personality disorder that helps clients gain a more realistic sense of self, learn skills for regulating emotions and solving problems, and correct black-and-white thinking. The name "dialectical" refers to balancing acceptance and change.

Splitting

A psychoanalytic concept particularly associated with borderline personality disorder. The person sees others (and themselves) as entirely good or entirely evil, with no integrated middle ground. They vacillate between these two extremes.

Mentalization-based treatment (MBT)

A therapy for borderline personality disorder based on the idea that these clients have difficulty understanding the mental states of themselves and others, rooted in childhood trauma and poor attachment. The therapy provides validation and helps patients appreciate alternative perspectives.

Transference-focused therapy (TFT)

A psychodynamic therapy for borderline personality disorder that uses the therapist-patient relationship to help clients develop a more realistic understanding of themselves and their interpersonal patterns.

Systems training for emotional predictability and problem solving (STEPPS)

A cognitive group intervention for borderline personality disorder that challenges irrational and maladaptive cognitions.

Core Content

Cluster B Overview

• People with these disorders tend to be manipulative, volatile and uncaring in social relationships

• They are prone to impulsive and sometimes violent behaviours showing little regard for their own safety or the safety of others

• Common features across the cluster: suicidal or self-damaging behaviours, hostile acts against others, and a lack of concern for others

Borderline Personality Disorder

Clinical picture

• Periods of extreme self-doubt alternating with grandiose self-importance, accompanied by a need for others to support their self-esteem

• Prone to transient dissociative states (feeling unreal, losing track of time)

• Extremely unstable interpersonal relationships: switch from idealising others to despising them without clear provocation

• Unstable moods: bouts of severe depression, anxiety or anger that seem to arise frequently and without cause

• Impulsive, self-damaging behaviours are very common

• High comorbidity makes it complex to diagnose and treat: substance abuse, depression, GAD, PTSD, phobias

• 75% attempt suicide; 10% die by suicide; greatest risk period is 1–2 years following diagnosis

• Hispanics show higher rates than whites or African Americans, possibly linked to extreme stress (though overdiagnosis relative to cultural norms may also play a role)

• Chronic but not necessarily permanent: 85% show remission of symptoms within 10–15 years, with only a minority relapsing (relapse often triggered by stressful life events and lack of social support)

• Can hold jobs, but maintaining positive social relationships is a persistent difficulty

• Prevalence: 5.9%, more commonly diagnosed in females than males (though the gap is small)

Theories

• Fundamental deficits in emotion regulation: greater mood variability, more negative emotional baseline, slower return to baseline after emotional disruption, unwillingness to tolerate distress to reach a goal

• Cognitive: hyperattentive to negative emotional stimuli; memories tend to be negatively biased; attempts to suppress negative thoughts typically fail, leading to rumination or impulsive/aggressive acting out

• Interpersonal difficulties: struggle to empathise, poor problem-solving in social situations

• Childhood instability, neglect and parental psychopathology: children in these environments struggle to learn appropriate emotion-regulation skills. They come to rely on others for coping but lack the self-confidence to ask for help maturely, so they become manipulative and indirect

• Psychoanalytic view: never fully differentiated their self-concept from their view of others, making them extremely reactive to others' opinions and to the possibility of abandonment. When they perceive rejection, they may reject themselves through self-punishment or self-harm. Early caregivers rewarded dependence and were hostile when the child tried to separate, preventing integration of positive and negative qualities (this produces splitting)

• Neuroimaging: amygdala and hippocampus are smaller in volume compared to those without the disorder. Amygdala (emotion processing) shows greater activation in response to emotional faces. Structural and metabolic abnormalities in the prefrontal cortex

• The disorder runs in families (supported by twin studies)

Treatment

• Dialectical behaviour therapy (DBT): the most prominent treatment. Teaches clients to monitor self-disparaging thoughts and black-or-white evaluations, challenge them, learn assertiveness skills for close relationships, and control impulsive behaviour by monitoring triggers. Evidence shows reductions in depression, anxiety and self-harm, with improved interpersonal functioning

• STEPPS: a cognitive group intervention that challenges irrational cognitions. Shows improvement in negative affect, impulsivity and functioning

• Transference-focused therapy: uses the therapist-patient relationship to build healthier self-understanding. Reductions in suicidality, impulsivity, aggression and anger

• Mentalization-based treatment: provides validation and support; helps patients appreciate alternatives to their subjective sense of self and others by using good relationships as illustrations. Five-year follow-up shows less medication use, fewer suicide attempts, better functioning across several dimensions

• Medications: mood stabilisers (aripiprazole, lamotrigine) and atypical antipsychotics (olanzapine). Serotonin reuptake inhibitors lack supporting evidence. Overall, results of drug treatment have been mixed

Histrionic Personality Disorder

• Rapidly shifting emotions and intense, unstable relationships

• Unlike borderline, lacks self-destructiveness, chronic anger and feelings of inner emptiness

• Behaves in ways designed to draw attention: highly dramatic, overtly seductive, flamboyant about physical appearance

• Others perceive them as shallow, unable to delay gratification, demanding and overly dependent

• Often alienate friends through constant demands for attention

• Prevalence: 1.84%, more common in women

• More likely to be divorced; tend to exaggerate medical problems (similar to somatoform presentations); more medical visits than average; increased rate of suicidal threats and behaviour used to coerce attentive caregiving

• Usually seek treatment for depression or anxiety, not the personality disorder itself

Theories

• Little is known about effective causes or treatments

• The disorder clusters in families

Treatment

• Psychodynamic: uncover repressed emotions and needs, help express them in socially appropriate ways

• Cognitive: identify the client's assumption that they cannot function independently, help formulate goals that do not rely on others' approval. Therapists challenge dramatic evaluations and suggest more adaptive ones

• Some evidence of reductions in self-reported depression and interpersonal difficulties, but no empirically controlled trials exist

Narcissistic Personality Disorder

• Grandiosity is the distinguishing feature: preoccupied with self-importance, fantasies of power and success, viewing themselves as superior

• Shares most symptoms with histrionic personality disorder, but narcissistic individuals rely on inflated self-evaluations and see dependency on others as weak and threatening

• Interpersonal relationships: entitled demands, ignoring or devaluing others' needs, exploiting others for power, arrogant and condescending. Notably, no abandonment issues (unlike borderline)

• Often annoy and alienate people in their lives

• Can be successful in cultures that reward self-confidence (e.g. the U.S.)

• When they overestimate their abilities, they make poor career choices and experience repeated failures

• Prevalence: 7.7% of men and 4.8% of women; more prevalent among younger adults

• High rates of substance abuse, mood and anxiety disorders

• Increased rates of physical and sexual aggression, impulsivity, homicidal thoughts and suicidal behaviour

Theories

• Psychodynamic: symptoms are maladaptive strategies for managing emotions and self-views. Did not develop a realistically positive self-view or adaptive coping strategies as children, so they rely on praise and domination for self-esteem

• Cognitive: unrealistically positive assumptions about self-worth resulting from overindulgence and over-evaluation by significant others in childhood. The belief in being unique or exceptional develops as a defence against rejection or unmet emotional needs

• Pincus and Lukowitzky distinguish two subtypes:

  • Grandiose: copes with self-esteem difficulties by viewing himself as superior, engaging in grandiose fantasies; entitled, exploitative, envious and aggressive

  • Vulnerable: copes with self-esteem difficulties through grandiose fantasies to quell intense shame; hypersensitive to rejection and criticism, avoids others

• History of childhood adversity, abuse, neglect, or a parent with psychopathology

Treatment

• Tend not to seek treatment unless depression or severe interpersonal problems force it (they view problems as belonging to others)

• Pose significant challenges to the therapeutic alliance

• Cognitive techniques: develop more realistic expectations of abilities and greater sensitivity to others' needs by challenging self-aggrandising interpretations

• Progress is slow; clients usually leave therapy once acute symptoms subside

• No controlled treatment studies have been published, including medication trials

Common Misconceptions

• Students often equate borderline personality disorder with "being moody." The disorder involves a specific pattern of instability across self-image, relationships and affect, combined with impulsivity and dissociation. Mood swings alone do not qualify.

• Students confuse histrionic and narcissistic personality disorders because both involve attention and admiration. The key difference: histrionic individuals seek attention through emotional display and seductiveness, while narcissistic individuals seek admiration for their perceived superiority. Narcissistic individuals also see dependency as weakness, which histrionic individuals do not.

• Students sometimes think borderline personality disorder is permanent. While it is chronic, 85% of patients show symptom remission within 10–15 years.

• Students forget that antisocial personality disorder requires evidence of conduct disorder by age 15 and cannot be diagnosed under age 18.

Why It Matters / Exam Flags

⚠️ Know the four Cluster B disorders and the key feature that distinguishes each (especially borderline vs. histrionic, and histrionic vs. narcissistic).

⚠️ Be able to describe dialectical behaviour therapy (DBT) and what it targets: black-and-white thinking, emotion regulation, assertiveness, impulse control.

⚠️ Know the suicide statistics for borderline: 75% attempt, 10% die, highest risk 1–2 years post-diagnosis.

⚠️ Understand the concept of splitting and which disorder it is most associated with (borderline).

⚠️ Know the neuroimaging findings for borderline: smaller amygdala and hippocampus, greater amygdala activation to emotional faces, prefrontal cortex abnormalities.

⚠️ Narcissistic personality disorder has NO controlled treatment studies published, not even medication trials. This is a commonly tested fact.

⚠️ Antisocial PD requires conduct disorder by age 15 and cannot be diagnosed before age 18.

Quick Self-Test

1. True or False: Histrionic personality disorder includes chronic feelings of inner emptiness and self-destructive anger.

1. Fill in the blank: The primary treatment developed specifically for borderline personality disorder is called ______.

1. True or False: Narcissistic personality disorder involves significant abandonment fears.

1. Fill in the blank: Approximately ______% of people with borderline personality disorder attempt suicide.

1. True or False: Mentalization-based treatment is grounded in the theory that borderline clients have difficulty understanding mental states due to childhood trauma and poor attachment.

Answers: 1. False (those features belong to borderline; histrionic lacks them). 2. Dialectical behaviour therapy (DBT). 3. False (narcissistic individuals do not have abandonment issues; that is a borderline feature). 4. 75%. 5. True.

Practice Q&A

Q: What is splitting, and which personality disorder is it most associated with?

A: Splitting is the tendency to see people (including oneself) as entirely good or entirely evil, vacillating between the two views with no integrated middle ground. It is most associated with borderline personality disorder and is explained by psychoanalytic theory as a failure to integrate positive and negative qualities due to inconsistent early caregiving.

Q: How does narcissistic personality disorder differ from histrionic personality disorder?

A: Both seek attention and admiration, but narcissistic individuals rely on inflated self-evaluations and view dependency on others as weak and threatening. Histrionic individuals seek attention through emotional display and seductiveness without the grandiosity or contempt for dependency. Narcissistic individuals also lack the abandonment fears seen in borderline.

Q: Name three evidence-based treatments for borderline personality disorder.

A: Dialectical behaviour therapy (DBT), mentalization-based treatment (MBT) and transference-focused therapy (TFT). STEPPS (a cognitive group intervention) also has supporting evidence.

Q: What neuroimaging findings are associated with borderline personality disorder?

A: Smaller amygdala and hippocampus volumes, greater amygdala activation in response to emotional faces, and structural and metabolic abnormalities in the prefrontal cortex.

Q: Why is narcissistic personality disorder particularly difficult to study from a treatment perspective?

A: No controlled psychological treatment studies and no medication trials have been published. Clients tend not to seek treatment unless forced by depression or severe interpersonal problems, and they usually leave therapy once acute symptoms resolve.

Connections to Other Topics

Borderline personality disorder connects to mood disorders (Ch. 5–6) because of its high comorbidity with depression and the superficial resemblance of mood instability to bipolar-like cycling. The neuroimaging findings (amygdala, hippocampus, prefrontal cortex) tie back to the biological foundations of emotion covered earlier in the course. Antisocial personality disorder connects to developmental psychology through its requirement for conduct disorder by age 15, and to the broader debate about criminal behaviour and psychopathy covered in forensic psychology.

Related Terms / Search Tags

Cluster B, dramatic-emotional, borderline personality disorder, BPD, histrionic personality disorder, narcissistic personality disorder, NPD, antisocial personality disorder, ASPD, conduct disorder, dialectical behaviour therapy, DBT, STEPPS, transference-focused therapy, mentalization-based treatment, splitting, grandiosity, abandonment, impulsivity, self-harm, suicide risk, amygdala, hippocampus, prefrontal cortex, mood stabilisers, aripiprazole, lamotrigine, olanzapine, Pincus and Lukowitzky, grandiose narcissism, vulnerable narcissism, abnormal psychology chapter 9