Twin Studies Suggest Childhood Trauma is Major Determinant in Development of Psychiatric Disorders

New findings challenge traditional views on the origins of mental disorders, revealing the significant role of childhood trauma.


A new study’s methodology—focusing on twins who share the same genes but not the same experiences—provides compelling evidence that challenges the dominance of biological determinism in psychiatry.

The study, led by Hilda Björk Daníelsdóttir at the University of Iceland, leveraged the unique situation of twins to dissect the complex interplay between genetics and environment in the development of psychiatric disorders. The results suggest that experiences of childhood trauma distinctly influence mental health outcomes in adulthood beyond the influence of genetic factors.

“Studies have consistently reported associations between ACEs and an increased risk of psychiatric disorders in adulthood,” the researchers write. “However, given that ACEs and psychiatric disorders cluster within families, few studies examining associations of ACE exposure with subsequent psychiatric disorders have been equipped to disentangle these associations from potential genetic confounding and other risk factors shared by family members.”

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  1. “the authors emphasize the need for evidence-based trauma therapies and interventions that are widely accessible so as to not exclude the most vulnerable populations that may need treatment the most.”

    For goodness sake, today’s DSM “bible” billing “mental health professionals” can’t even bill to help child abuse survivors today. Why don’t the “mental health professionals” start by allowing themselves to actually honestly bill to help child abuse survivors first?

    Or better yet, since what is actually helpful for a child abuse survivor to heal, is getting him/her away from the abusers, treating an abuse survivor with love, mutual respect … and justice – none of which the “mental health” industries seem capable of doing. Quite to the contrary, today’s “mental health professions” are basically a multi-billion dollar – primarily child abuse covering up – group of industries.

    … But a child abuse survivor can heal, and go from remedial reading in first grade (after the abuse), to getting 100% on his state standardized tests in eighth grade, to graduating from university Phi Beta Kappa, in addition to winning multiple psychologic university and civic awards since then.

    So it’s very important that the “mental health industries” end their systemic “dirty little secret of the two original educated professions'” faustian “partnership” with the mainstream religions. And get out of the child abuse covering up business, for those paternalistic religions.

    And please stop incorrectly assuming all child abuse survivors – and their legitimately concerned mothers – need “mental health treatment,” or are stupid, or “fictional” – scientifically “invalid” DSM “bible” billers and neurotoxic poisoners.

    Writing the truth about your industries’ systemic crimes is good therapy. Thank you, MiA, for allowing the former “patients'” research to be heard.

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  2. Twin studies are a SHAM The hypothesis of the MSTRA twin investigation is true: separate identical twins at birth, and if their behavior is identical later in life, it is genetic. The REALITY of the MSTRA study is staggering: the study itself explains how the twins were NOT separated at birth and did NOT live apart during their childhoods. The MSTRA is a study in CONFIRMATION BIAS.

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  3. Surely I have misunderstood this study because it is so poorly conceived. The study claims that in identical twins, even ONE adverse childhood event results in a likelihood of a subsequent diagnosis of a mental disorder. What isn’t wrong with this?

    First, even identical twins may have different genetic makeups. Second, even in the same household, experiences can be very different. Third, the study does not examine ACEs but the recollection of ACEs and it’s not convincing to claim that a large population size would mitigate against this problem.

    In addition, we have no convincing definition of a mental disorder. Also comparing the experience of identical twins to that of fraternal twins is not illuminating.

    There are an awful lot of poorly done studies, but psychological studies seem worse than most.

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  4. Rather than these studies which are mostly pointless for the average person who ends up in Psychiatry, if all you researchers, MD Psychiatry students, Psychology students etc. parted with some of your property/money and gave it to abuse victims and the like, you might actually make a positive contribution to the world than just publish (mostly) useless paper after useless paper.

    Sure, it will not help the guy who comes from an amazing family but still suffers from hallucinations. But it will help the woman who is depressed because she is stuck with a terrible husband but is unable to leave because she is financially dependent on him. A good chunk of patient load will reduce.

    But we all know most of you will not do that. It goes against you having a career by uselessly sitting in a department and talking pseudo-consoling nonsense to this person over multiple “sessions” than a sure shot solution that will make her never require you again. God bless the minority of you who might have done that. “Help” helps a human being. “Treatment” helps your career. If you have no legitimate methods of help, please stop taking courses in mental health. Don’t become dishonest, useless burdens to society by injecting yourselves in roles where you are deemed to be helpers and where people will unnecessarily go to you only for you to waste their time, create more problems than you solve and then retire and die.

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  5. Also, most of you guys solve problems like this:

    i.) “Doctor, my wife is cleaning my hands over and over again for no reason, please help her”.

    ii.) “Doctor, I am hearing scary voices, please help”.

    There are way too many of you doing that.

    We need people who solve these problems:

    i) “I was mocked by the people in the rehab facility when they heard my diagnosis”

    ii.) “My parents call me genetically defective and gaslight me because of psychiatric diagnoses”.

    The second sort of problems again jeopardize your career because people like you are pretty directly responsible for creating those problems. But you have to solve the shit your own profession creates.

    You tell people on our side of the table: “Don’t like Psychiatrists, don’t go to them!”. You don’t like what we say, don’t take Psychiatry in med-school or any other mental health courses. Take dentistry, cardiology etc. and you don’t have to listen to all this.

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  6. I’m not even reading the two articles on child abuse neglect pathological parents today I couldn’t be bothered I lived the fact when society community finds out you have a weakness they open the wound with prejudice discrimination revictimization and blaming the victims treating you like non person and targeting you for crime like rape sodomy fraud theft extortion etc even intrafamiliar crime continues as scapegoats and for those family members that identify with their abusers and aggressive steal from the gentler ones the necessities of life sometimes even it is sanctioned in mental health laws to prep your victims groom them with blame and sliming you for the hell you went through never letting you forget protecting your taxpayers abusers. In the future do not target the vulnerable and get it right next time all to flood your markets with big pharm ridiculous councellors theories and multimillion dollar educations that you can’t as a society stop and emancipate children from terror of parental violence starvation lack of clean water and give them human rights and a society that will give them a future and inclusion….in foster care abuse paid by state over and over until spewed out with nothing against the world.hand off our children and adult survivors from sick pathology and labels and enforced treatments and abuse in criminal justice systems

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