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What is Borderline Personality Disorder?

Borderline Personality Disorder (BPD) is a type of personality disorder that is characterised by sudden shifts in mood, difficulty regulating emotions, and the presence of unstable relationships. It is no surprise then, that BPD has a poor public perception. However, when you look at the symptoms of BPD, and the most prominent theory behind how it develops, we might get a greater appreciation for what it’s like to live with BPD.

Biopsychosocial Model of BPD using a venn diagram
Biopsychosocial Model of BPD

The Diagnostics and Statics Manual of Mental Disorders 5th edition (DSM-5) lists the following 9 symptoms of BPD. You need at least five of these symptoms (as assessed by a mental health expert) to be diagnosed:

  1. Frantic efforts to avoid real or imagined abandonment

  2. A pattern of unstable and intense interpersonal relationships characterised by alternating between extremes of idealisation and devaluation

  3. Identity disturbance: markedly and persistently unstable self-image or sense of self

  4. Impulsivity in at least two areas that are potentially self-damaging (e.g. spending, sex, substance abuse, reckless driving, binge eating).

  5. Recurrent suicidal behaviour, gestures, or threats, or self-mutilating behaviour

  6. Affective instability due to a marked reactivity of mood (e.g. intense episodic dysphoria, irritability or anxiety usually lasting a few hours and only rarely more than a few days)

  7. Chronic feelings of emptiness

  8. Inappropriate, intense anger or difficulty controlling anger (e.g. frequent displays of temper, constant anger, recurrent physical fights)

  9. Transient, stress-related paranoid ideation or severe dissociative symptoms

As with all mental health disorders, symptoms need to be at an extent that they impact on an area of life, and not a result of substance abuse. BPD is estimated to impact between 1-4% of Australians, with about 75% of those diagnosed being female.

The most prominent theory for how BPD might develop is the Biosocial Theory. This theory suggests that people are born with different sensitivity to emotion, in the same way that we are born with different sensitivity to chilli, heat, or sunlight. So at the same anger-provoking situation, one person might feel mad, while another might feel enraged! People with high sensitivity to emotion will feel their emotions more intensely, for a longer duration, and will have more difficulty returning to emotional baseline.

If the people around someone with high sensitivity to emotion recognise this, they may do things to help that individual validate their emotions, and bring them back to baseline. However sometimes the social environment can invalidate an emotionally sensitive person as they might feel that the emotion displayed is out of proportion to the triggering event. We hear things like “why are you still angry?”, “You should be over it by now”, “I don’t understand why you’re still stuck on this”, and “what’s the matter with you”.

When someone is biologically sensitive to emotions, and their social environment is invalidating of their emotional experience, we have an individual who has come to learn to mistrust their emotions, not understand what different emotions are for, not know how to manage their emotions, and tend to not share emotions with the people around them for fear of being different or misunderstood. This has follow-on implications on sense of identity (“I don’t know what I like or dislike”), concerns for abandonment (“people don’t understand me so they will all leave me”), impulsivity (“I feel good when I spend money”), self-harm (“maybe they’ll understand how hurt I am if they can see it”), and relationship difficulties (“this person doesn’t understand what I feel, they don’t love me”). Overall, the experiences of someone with BPD in one of intense emotional experiences that are very frequently invalidated by the people around them.

The good news is there is treatment available! The gold standard of treatment for BPD is Dialectical Behaviour Therapy (DBT). To find out more about DBT see our blog post here, or call us on 02 8091 7867 to make an appointment with one of our clinicians.

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