Doctors Stopped Believing in the ‘Chemical Imbalance’ Theory. But They Didn’t Tell Us.


From National Post: “Psychiatry has known for quite some time that the ‘serotonin theory’ of depression, the notion that too little of the brain chemical can be a cause of depression, a decades-old hypothesis and deeply entrenched trope in society that helped promote a class of antidepressants taken by millions of Canadians, is wrong, says Montreal psychiatrist Dr. Joel Paris.

‘You want to know why it took so long for the truth to come out,’ Paris, a professor of psychiatry at McGill University, wrote in an email. ‘I am afraid this has something to do with the toxic relationship between industry and academia.’ Drug companies encourage doctors to prescribe often, and heavily, he said, and have ‘paid many academic psychiatrists to promote their products.’

Two months after a major review found no support for the hypothesis that depression is caused by lowered serotonin activity or concentrations, no convincing evidence of a ‘chemical imbalance,’ the paper is still stirring controversy. Its authors say they have been ridiculed and attacked and accused of dog whistling to ‘far-right’ commentators who have ‘groundlessly’ linked antidepressants to mass shootings. Responses from psychiatrists have been oddly contradictory, ranging from ‘nothing new here, of course we knew it was never serotonin, it was never that simple’ to criticisms that it’s premature to toss out the serotonin theory outright and that the authors missed some studies and interpreted others incorrectly.

‘But the main thing that has got people riled up is that we have dared to draw conclusions about antidepressants,’ the study’s lead author, Dr. Joanna Moncrieff [told National Post this week] . . .

Moncrieff’s study didn’t look at the efficacy of SSRIs, just how likely they are to do what people have been told they do . . .

‘It seems the main criticism is that “antidepressants work,”’ Moncrieff said. ‘It doesn’t matter how they work. It doesn’t matter that the original idea, the original theory for how they work is unproven. “They work,” and that’s all that matters.’

To Moncrieff, it matters. ‘Because whether they work or not depends on how we understand what they are doing.’ And if they are not correcting a serotonin imbalance, or reversing some underlying mechanism of depression, what are they doing? . . .

The serotonin ‘bombshell’ caused an international media frenzy, though was largely ignored in Canada, with many headlines along the lines of, ‘How were so many duped?’ Some psychiatric opinion leaders dismissed the study as ‘old wine in new bottles,’ arguing that no serious psychiatrist today believes depressions are due to a tidy, simple imbalance in brain chemicals or ‘serotonergic deficit.’ Apparently no one told the public. One survey of Australian adults found 88 per cent believes the ‘chemical imbalance’ hypothesis of depression. A British Columbia government website says the SSRI escitalopram ‘works by helping to restore the balance of a certain natural substance (serotonin) in the brain.’ Forbes Health last week quoted a Vanderbilt University psychiatrist explaining that SSRIs like Prozac, Paxil, Zoloft and their generic equivalents work by boosting serotonin activity in the brain. ‘The idea is that if you have more serotonin in your synapses (regions in the brain where nerve impulses are sent and received) the better your mood will be.’

‘It may well be the case that psychiatrists have a more “sophisticated” understanding of the role of serotonin than the lay public,’ Moncrieff and one of her co-authors, Dr. Mark Horowitz later wrote for Mad in America, ‘but psychiatrists have failed to correct this misunderstanding.’

The serotonin theory seemed promising when first introduced 60 years ago, ‘but was soon discarded,’ said Dr. Allen Frances, a professor emeritus of psychiatry at Duke University who led the task force that created the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders in 1994.

The association was weak and often didn’t replicate . . .

But the ‘chemical imbalance’ theory was a marketing godsend for drug companies, following the benzodiazepine crisis in the 60s and 70s, when the highly addictive tranquilizers were ‘doled out by the bucketload’ to people, particularly women, who were unhappy ‘just to numb their unhappiness,’ Moncrieff said.

In the 1980s, when the first SSRI, Prozac, was launched, ‘the pharmaceutical industry knew it couldn’t market them in the same way (as benzos) because numbing someone’s unhappiness had got a bad rep with the benzodiazepines,’ Moncrieff said. ‘So, it had to convince people that they had an underlying disease and needed to take the drugs for an underlying disease.’

. . . But if psychiatry knew the chemical imbalance theory isn’t real, they had a professional duty to tell people, said Marnie Wedlake, a psychotherapist and assistant professor in the School of Health Studies at Western University.

‘If they knew this was a false narrative, as the self-proclaimed and publicly recognized primary experts, they should have been out there saying, “No, no, no. Correction.” But they did not. They just let it go.’

Still, while it would be easy to pile all blame on psychiatry and the drug industry, ‘that’s too tidy,’ Wedlake said.

As a species, we don’t know what to do with despair anymore

We’ve allowed a ‘pathologizing’ of our human condition, she said. ‘If I’m feeling happy and peaceful, that’s great, but anything else has become a “symptom.”‘ When high school kids talk about their emotions today, ‘they use language that medicalizes their thoughts and feelings,’ she said. ‘It’s just my OCD,’ obsessive compulsive disorder. ‘I was a shy kid. Kids in my class now in university, they’ve got social anxiety disorder.’

. . . ‘As a species, we don’t know what to do with despair anymore. Ideally, we would say, “Okay, I’m feeling somewhat despairing, it’s just part of my life, the full colourful spectrum of who I am. Sometimes I’m angry, sometimes I’m sad…” But it has been pathologized, and we don’t know what to do with it.’”

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  1. I don’t think it’s appropriate to just let the “more sophisticated understanding” claim stand, as if deference is warranted.

    For science (and medicine) to be science, you have to be scientific. Sophistry from the likes of Pies, who recently repeated this nonsense, is anti-science. It’s not even Feynman’s “cargo cult medicine”, since it’s assertively contemptuous of scientific rigor and prudence. In science, you check your work, you question everything, and you never stop. You don’t try to stop others from questioning your sense of authority and entitlement. If there is understanding, prove it.

    And the dog-whistles to try to malign real scientists, recipients, and advocates as “right wing” or extremists or disingenuous has no lack of irony. For individuals who write how “they” need to be coerced into line in exactly those sorts of places – think tanks like the Manhattan Institute – and who have jumped at every opportunity to reduce the rights and health of “them” and deny their own behavior while claiming perpetual victimhood and throwing out conspiracy theories and on and on, there apparently is no such thing as integrity. Or is it insight? Or both. There’s an awful lot of Trumpism, but it isn’t coming from “them”. Maybe we should start seriously calling out “mentalillnesspolicy” (.org), the pretend institute from Jaffe and Torrey, and highlighting both its content and its impact, and the antics to promote policy aims. Kevin’s Law? Maybe we should start talking about what went into that (and who helped pay).

    Anyway, I’m actually less patient also with discussions about the limitations the practice has to understand distress. I’m more concerned with what actual clinicians do, and with policies put in place that are based on bogus anti-science sophistry. There is no caring and investigate and balanced approach in any state institution. Talk to clinicians, and they don’t even talk about chemical imbalances, except as excuses to recipients (when there is any explanation) and courts (and the fact that these assertions are continually made further undermines any claim that psychiatrists at large have not made these claims or have a better understanding of anything); they simply assert, in line with expectation, that all recipients are essentially subhuman and must comply (with drugs) and validate what is done to them. It’s automatic. Mischaracterization of a person and their behavior is a matter of course to fit a rote and convenient narrative on diagnostic nosology and treatment. Recovery is heretical and denied. Harm imposed is denied or blamed on the victim, or the condition, which is synonymous with the victim. Insight is automatically lacking as convenient, and may either never be gained or is defined not as insight, but as compliance and validation. What “chemical imbalances” has always been, and will continue to be, is a vague, hand-wavy excuse to rationalize convenient narratives in diagnosis, policy, compliance etc. as well as why treatment is “you take drug and say thank you”. In the face of courts and insurance claims and other business, something simple and measurable is needed, and following the civil rights movement, a response to arbitrary confinement and the bad press about surgeries had to give existing structures an “out”. Que “chemical lobotomizers”. It’s not like the history isn’t history. Now, “You thingy, you take drug, always, no matter what”. This is not sophisticated, and it’s not effective, and it’s dishonest and exploitative and abusive.

    We have some pretty brazen nonsense out there. The culture pervading psychiatric practice is as empty as it is paranoid, dishonest, and violent, and the responses to the study are par for the course.

    • Well said, George!

      “it doesn’t matter if serotonin is not how they work. What matters is that they work!”. Except in the many, many instances where they DON’T work — and whatever that end of the “don’t work” spectrum is called where people get akathisia and even at times tragically end their own lives or other people’s. We will blame the patient always. As long as there is a patient to blame, we will blame the patient. We have an endless list of names to call them. Treatment resistant, non-compliant, outliers, beyond help, personality disordered. Do other medical specialties have long lists of pejorative labels and insults for people who get worse under their care?For the psychiatrists who have not admitted to wrong-doing at this point, this is a self-selected group who is congenitally incapable of admitting wrongdoing. They will go to their graves blaming someone else, something else, or saying that all they’ve ever done is help people, people who no one else wanted to deal with. Their egos have been injured and they can’t handle it.

      • And as I have pointed out elsewhere, by this definition, alcohol, marijuana, and heroin also “work” in that they have discernible effects on the mind and on the brain, which some people find desirable or relieving to take. I would hope that a medical specialty would aspire to a higher goal that, “Here, take some of these, you’ll feel better.” Anyone with a drug-seeking auntie can get as good service from her: “I’ve got valium, Percocet, klonapin, oxy, what do you need?”