This site aims to consider contentious questions about BPD head on. In that light, I will address the “broken brain” theory of borderline personality disorder. What is this theory?
The Broken Brain / Genetic Causation Theory of BPD
The broken brain theory states that children who grow up to become borderline are born with a specific constitutional weakness based on unfortunate genes passed down to them by their parents. Supposedly these children, unlike healthy individuals, are constitutionally unable to regulate their emotions from birth. Their severe emotional problems therefore have little to do with environmental influences, and are instead a consequence of bad genes which prevent their limbic system from functioning properly. This idea is discussed on many online forums about BPD. Although I find it difficult to take seriously, I will discuss this notion at length because many borderlines and their family members believe it.
It is useful to first consider the possible benefits of this belief before contesting it. “Cui bono?’ is a Latin phrase meaning “Who benefits?”, and in its idiomatic form it implies the existence of a hidden motive. Understanding how pharmaceutical companies, psychiatrists, and family members benefit financially and emotionally from the promotion of such a belief system is important in understanding how the belief system develops.
The benefits of promoting a genetic basis for BPD include:
1) Simplification – Viewing the often-difficult person with BPD as having a broken brain relieves that person’s therapists and/or family members from having to consider them as a complex human being with a unique history that has contributed to their condition. The simple idea that their brain doesn’t work replaces an in-depth understanding of the borderline as an individual. This way of thinking crucially eliminates the possibility that a broken brain might be partially or wholly the result, rather than the cause, of their past and present emotional problems. In other words, it seeks to minimize the role of the environment and past interpersonal relationships.
2) Relief of Guilt and Shame – The broken brain theory relieves family members from feelings of guilt or shame about how they related to the borderline individual in the past. If the borderline’s problem is genetic, nothing different could have been done to stop them turning out this way. For a formerly abusive and/or neglectful parent, it might be a great relief to think that their child’s problems are due to genetic bad luck, rather than to physical abuse and lack of love. For an ineffective therapist, it might be comforting to feel that the patient’s continued suffering and seeming inability to change is due to misfiring neurons, rather than the therapist’s own lack of knowledge about how to treat BPD.
This is not to blame the parents. Parents who mistreat and neglect their children, as parents of borderline-children-to-be often do, usually have their own severe emotional problems passed down to them from their own parents. They cannot be held morally responsible for continuing a generational legacy of poor parenting that often began before they were born.
3) Financial Benefit – Pharmaceutical companies make billions of dollars by over-medicalizing BPD and hundreds of other “disorders.” It is well known that the Diagnostic and Statistical Manual of Mental Disorders continually expands to encompass dozens of new mental health “disorders.” In the last few decades, these companies have made massive gains in sales of their products, developing pills for patients with almost every emotional problem imaginable.
In this light, promoting the idea that Borderline Personality Disorder is caused primarily by genetic and biological factors, and thus requires long-term medication to treat its symptoms, makes financial sense for drug companies and psychiatrists. It is part of a long-term movement in the US and global mental health industry. Pharmaceutical companies make tens of billions of dollars annually by promoting the pharmaceutical treatment of hundreds of supposed emotional disorders. Psychiatrists make hundreds of thousands of dollars annually for prescribing pills which have dangerous side effects and often do not work.
It is no surprise then that these companies and psychiatrists are heavily invested in promoting the genetic/biological-causation viewpoint, since it supports their income and continued existence. Even if the validity of certain diagnoses and treatments are doubtful, Big Pharma attempts to profit from them anyway. If one doubts that Big Pharma companies would distort the truth to protect their profits, one should look at how Big Tobacco companies lied on a massive scale about the true harm of tobacco during the 1970s and 1980s.
(Aside: I was recently entertained to read about the new disorders in DSM V. Do you have Hypoactive Sexual Desire Disorder, Caffeine-Induced Sleep Disorder, or Disruptive Mood Disregulation Disorder? Do you think that your psychiatrist can reliably diagnose these disorders, and prescribe you the appropriate pills to treat them? If yes, then you should be a supporter of DSM V!)
Evidence for the Genetic Basis of BPD – The Problem of Diagnostic Validity and Reliability
So, is there good evidence that Borderline Personality Disorder is caused by a broken brain, i.e. by genetic and hereditary factors?
To begin addressing the genetic argument, it is useful to note that in scientific research, the burden for proving a theory is placed on the person who proposes it. In other words, a theory is not accepted until it can be proven via repeated, observable experiments that it has validity and reliability. Validity means that a given result is true, accurate, and meaningful, and reliability refers to the notion that a process can be consistently repeated and yield the same result.
To start with, a valid, reliable theory about a mental health disorder should involve a disorder which can be reliably diagnosed. On this measure, the broken brain theory of BPD is a failure. The problem is that BPD itself, along with most other mental health “disorders”, is not a a valid or reliable diagnostic entity. Rather, the entire notion of BPD is built upon a fragile foundation, involving subjectively assessed traits which no brain scan, blood test, or gene test can reliably diagnose.
Since there is no physical test which can reliably diagnose BPD, therapists must use their subjective judgment about whether or not a person meets at least 5 out of 9 DSM criteria. As noted in the books listed below, different therapists often disagree as to whether the same individual has a given mental health disorder, and this certainly applies to BPD. Where does one draw a line before which one is non-borderline or even healthy, and beyond which one suddenly has BPD?
When I began to consider this question, BPD’s weak position as a scientific diagnosis became apparent. Are there great therapists who can reliably detect when someone has just enough fear of abandonment, or just enough evidence of black and white thinking, or just enough self-destructive acting-out, for these traits to collectively qualify them for the clinical picture needed with a BPD diagnosis? Who decides exactly what degree of poor self-esteem, how severe of an identity disturbance, or how much splitting, counts as a trait contributing toward a BPD diagnosis? How does one scientifically and reliably include or discount such symptoms in all their different degrees and presentations?
If these questions cannot be reliably answered, the whole notion of establishing a genetic basis for BPD is undermined. If mental health professionals cannot reliably diagnose who has BPD at a given time, how can researchers reliably test what causes it? How can one be sure that the people one chooses for testing do have BPD, and they they continue to have it throughout one’s experiment? It makes little sense to test a theory based upon a condition which has not been proven to exist as a discrete entity, and which cannot be reliably diagnosed.
This argument might strike some as outrageous, crazy, or outside the norm. If so, that is fine, since I am merely stating my opinion. My view of BPD is unconventional, but that is not a bad thing. Rather, it is something that has helped me. I do not think that BPD is a useless concept. Instead , I view BPD as a developmental metaphor – one that symbolizes the lower part of a continuum of human functioning stretching between emotional health and psychotic illness, rather than a scientifically valid, reliable diagnosis. I understand why some people simplistically believe that BPD exists as a discrete disorder that one “has” just like one has diabetes or cancer. But that is not my viewpoint.
Can Brain Scans Prove a Genetic Basis for BPD?
Back to the issue of whether the genetic basis for BPD has been proven. Let us assume for the sake of argument that BPD is a valid diagnosis that can be tested scientifically. One possible way of proving a genetic basis for BPD might be to identify the existence of long-term abnormalities in the brains of those diagnosed with BPD when compared with healthy controls. Both groups – those who grew up to become borderline, and those who grew up to become healthy adults – would have to be studied from a young age, with their brains scanned repeatedly to detect changes in structure and function over time. Such a study would have to be massive in scale and timeframe, relying on repeated, costly brain scans over many years. To my knowledge, no one has yet attempted such a study for BPD.
Even if such a study were made, it would face the thorny challenge of conclusively proving that differences in observable brain function between borderlines and healthy control subjects were the cause of past and current emotional problems, rather than the result of past environmental problems. It would have to demonstrate that similar environmental conditions (i.e. a similar amount of traumatic childhood experience) existed both for those who became borderline and those who remained healthy. Otherwise, the presence of environmental trauma could be a confounding factor, as the greater contributor in the cases of those who became borderline.
One might say that it is enough to simply scan the brains of borderlines versus non-borderlines, and identify differences that prove a genetic basis. This is scientifically baseless. Identifying present-day differences in the brains of borderlines and non-borderlines does nothing to prove the degree to which genes and/or past environmental influence caused these differences. This would be a circular argument.
Several recent studies have indicated that a genetic basis for BPD has been established based on studies of identical versus fraternal twins. These studies usually find a higher concordance (diagnosis rate) for BPD among identical twins, who share 100% of their genetic material, versus fraternal twins, who share 50% of their genetic material.
However, such studies have come under severe criticism, with detractors asserting that they suffer from faulty assumptions and research methods. The most serious issue is the Equal Environment Assumption (EEA). The EEA, which is crucial to the twin study method, means that researchers assume the environments of identical twins and fraternal twins to be extremely similar, or at least not different enough to influence a study’s outcome. The problem with this is that in-depth observational analysis of twins’ home environments have undermined this assumption, a fact many twin researches have already admitted. It is clear that identical twins are often treated more similarly, pushed to engage in more similar activities, and experience a closer psychological bond with each other compared to fraternal twins. This environmental difference could easily confound studies, accounting for the variation in rates of diagnosis for disorders including BPD.
Recently, twin researchers have attempted to take the position that identical twins’ genes cause or elicit more similar treatment from the environment, and that genes therefore explain the more similar environment of identical as compared to fraternal twins. In this way, the researchers maintain that the EEA is still valid, since genes are supposedly still the cause of observed environmental differences in how identical twins are treated, rather than these differences stemming from any choice by people in the external environment.
To me, and many other critics, this position relies on circular reasoning and is extremely weak. It is circular reasoning because it brazenly asserts that its conclusion proves its premise – i.e. it assumes to begin with that genes are the cause of the more similar treatment of identical twins versus fraternal twins. It then states that therefore the environment itself is not the cause of the more similar treatment of identical as compared to fraternal twins. In fact, without such circular reasoning, that “fact” has not yet been proven. For some people, this might be hard to wrap one’s mind around, but it is important to understand in order to undermine the basis of twin researchers. Without the Equal Environment Assumption, the whole foundation of twin research collapses.
There are many other problems with twin research, including small sample sizes, unreliable diagnoses of disorders under study, and investigator bias. Anyone seriously considering twin studies as indicative of a genetic basis for BPD should read the work of Jay Joseph, the preeminent critic of twin studies worldwide. Josephs’s books, The Missing Gene and The Gene Illusion, mercilessly expose the weaknesses of twin studies. Joseph’s work is notable for its meticulous attention to detail and to the importance of the scientific process.
Of course, even if twin studies themselves were to be valid, they would still face the problem, with Borderline Personality Disorder, of studying a diagnosis that has not been demonstrated to be scientifically valid or reliable. Therefore, twin studies of BPD face the Scylla and Charybdis of the severe methodological problems of twin research on the one hand, and the inherent unreliability of the BPD diagnosis on the other.
Views of Present Day Psychiatrists, Therapists, and Family Members
Psychiatrists and family members of borderlines often promote the idea that Borderline Personality Disorder is caused by a broken brain, without relying on any experimental evidence that proves that notion. In my view, the more plausible reality is that the symptoms collectively called BPD arise from a complicated, long-term interaction between the individual and their environment. In this view, constitution and genes are not unimportant. A person’s genetic endowment affects their level of vulnerability to stress and trauma, and therefore their vulnerability to developing “borderline” symptoms. But genetic endowment has not been proven to be the primary force that causes these symptoms, as in the broken brain theory of BPD.
Many more evolved psychiatrists and therapists actually subscribe to this dynamic or broader view, in which both environment and genetic endowment are important. Such therapists believe that the relationship between nature and nurture is complex, and therefore the proportional influence of each varies from case to case. In my experience, the therapists who have worked the most extensively with borderline individuals give a heavy weighting to the influence of environment trauma versus genetic contributions, while still acknowledging the importance of both. In my personal opinion, the environment is usually more important than genetic endowment in causing severe emotional problems. Everyone has a bias, and that is mine. Without the severe physical abuse and emotional deprivation that I endured over many years as a child, I highly doubt that I would have been diagnosed with BPD at age 18.
Many psychiatrists without in-depth therapy training, who do not understand the psychodynamic and/or psychoanalytic viewpoints on emotional illness and how to treat it, believe that “it is all biological”, regarding the environment as relatively important. Genetic researchers in universities and foundations sometimes subscribe to an almost entirely genetic viewpoint on mental illness. These researchers rarely work with or even encounter mentally ill people in person like therapists do. To me, their position is difficult to take seriously. However, given that their academic funding for research often depends on their promoting a genetic basis for emotional problems, with Big Pharma companies expecting them to find genes that cause the conditions under study, it is easy to see why they might cling to flimsy evidence for genetic causation.
The extremists who promote purely or mostly genetic theories of BPD need to be called out and discredited. They should not be given serious attention until they provide proof that BPD can be reliably diagnosed, along with experiments that clearly separate the causes and effects of brain-based biological differences.
The Tragic Effect of Genetic Theories of Mental Illness and BPD
The worst effect of genetic theories of BPD is to promote a sense of hopelessness in the person diagnosed with the disorder and their family. If the borderline has problems that are caused by a broken brain and bad genes, problems that can only be managed but not cured with medication, then they are doomed to suffer for life with a severe set of emotional problems from which deep recovery is not possible. This is often the underlying belief of biologically-based psychiatrists who treat BPD primarily using medication. As I have said elsewhere on this site, nothing could be further from the truth.
There are many great books that carefully consider the proof or lack thereof for gene-based theories of the etiology of mental health problems. Some of my favorites are listed at the bottom of this page. My favorite author in this regard is Jay Joseph, the California psychologist who was noted above.
My Own Experience as a Refutation of Genetic Theories
Several years ago, my therapist told me that you can only truly know something if you experience it for yourself. At the time, this was a new idea for me, since I did not trust my own thoughts and feelings. This statement came in the context of my starting to feel much better in several areas of my life, but having trouble believing in that feeling. I had trouble trusting my own progress partly because of my fear that if BPD were a hopeless, genetically-based condition, then my experience could not be real or would not last. My therapist encouraged me that if I felt better, that was real. Over time I came to trust my own experience more.
My own experience has been the best guide informing me about the validity of biological, genetically-based explanations of mental illness. The severe physical beatings that I received from my father, along with my mother and father’s inability to communicate love and make me feel secure, were massive factors in my development. They destabilized me emotionally as a young child and teenager, causing me to develop the symptoms that comprise Borderline Personality Disorder. I simply never had the chance to develop a secure sense of identity, self-esteem, and healthy, intimate relationships with my parents and peers. In its place, I was forced to use the primitive defenses of denial, avoidance, projection, splitting, acting out, etc. to defend against overwhelming fear, rage, and grief. The use of these defenses and my inability to trust others to help me as a teenager led me to develop all nine of the symptoms of BPD to varying degrees.
To me, it is obvious that genes and biology – while they are not unimportant – are not the primary causative factor for borderline symptoms and Borderline Personality Disorder. I understand why that might be hard to understand for those who have not experienced the symptoms and history of BPD. Although it is controversial, I believe that family members of borderlines are sometimes motivated by the oversimplification and the avoidance of guilt and shame that genetic theories of BPD allow for. If anyone has experienced a genuinely happy, secure childhood, and then gone on to inexplicably develop chronic, long-term BPD (and not just normal teenage angst), I would be morbidly fascinated to hear about that. However, I doubt that I will be hearing from too many people with that history, given the statistics on how frequently neglect and abuse are associated with the disorder.
In sum, I am proud to reject the idea that Big Pharma and many psychiatrists promote about BPD – the notion that it is caused primarily by biology and bad genes. My childhood experience of abuse, along with my successful recovery from BPD over the last 10 years, is all the evidence I personally need to conclude that the genetic theories are faulty and do not universally apply. Beyond my personal experience, the analysis above, which questions the validity of BPD itself and of the associated twin and gene studies, are more evidence that the issue of causation is not settled.
When it comes to those who promote genetic theories of the cause of BPD, people like me are their reckoning, here to end the borrowed time their theories have been living on.
If you would like to learn more about the problems surrounding modern psychiatry, here are a few relevant texts. I bought these books used at Amazon for very low prices, often only $5-10 including shipping.
Saving Normal, – by Allen Frances – In this book, the former chair of the DSM Task Force fiercely criticizes the new DSM-V. Frances asserts that the DSM V, without any scientific proof, turns every possible aspect of normal emotional struggle into a new mental health diagnosis.
Mad Science: Psychiatric Coercion, Diagnosis, and Drugs – By Stuart Kirk and David Cohen. In this book, the authors assert that American psychiatry’s claims about mental health diagnoses are riddled with unscientific claims, faulty reasoning, and missing evidence.
Bias in Psychiatry Diagnosis – By Paula Caplan. Caplan cogently illustrates how therapists frequently make unreliable psychiatric diagnoses. Caplan shows how therapists often misdiagnose individuals based on gender and race, and how this can have serious adverse effects in the courtroom and workplace.
The Heroic Client – by Barry Duncan. While this book is mainly about a positive vision of the therapist-patient relationship, it contains a large section critiquing current methods of diagnosis and treatment based on the DSM and psychiatry.
Warning: Psychiatry Can Be Hazardous To Your Mental Health – by William Glasser. A brutal indictment of modern psychiatry, which lays bare its unscientific assertions and points the way toward a better, client-focused form of treatment.
The Missing Gene – By Jay Joseph. A fantastically-detailed exposition of twin research and all the unfounded assumptions it is based on.
The Gene Illusion – by Jay Joseph. Another devastating critique of twin research. Joseph’s books focus on schizophrenia, but his methods of reasoning are easily transferable to twin research which addresses BPD.
Some of Jay Joseph’s articles on twin research from 2013 and before are available for free here – http://jayjoseph.net/publications
I welcome any correspondance at email@example.com
If you are struggling with BPD yourself or are trying to help a borderline individual, I would be happy to listen to your story and provide feedback if possible. Feel free to provide constructive criticism of this site also.
This article is the opinion of a non-professional layperson, and should not be taken as medical advice or as the view of a therapist who is professionally qualified to treat Borderline Personality Disorder or any other mental health condition. Readers should consult with a qualified mental health professional before undertaking any treatment.
– Edward Dantes