Thread by @garwboy

Depression is probably not caused by a chemical imbalance in the brain – new study

theconversation.com/depression-is-…

A few have asked me for my thoughts on this, so here's a thread

But basically; I agree. So much so, I've been saying it in most of my writing for 5+ years now

/1

You can see where the 'depression is due to a chemical imbalance in the brain' theory came from. Antidepressants were discovered (by accident), and they caused an increase in certain chemicals in the brain, reducing depressive symptoms. Ergo, depression = low chemicals

/2

Except since then, ample evidence has accumulated to show that depression is far more complex a thing than can be explained by 'not enough brain chemicals', and there are a lot more theories and models out there now that try to explain it more thoroughly

/3

The 'chemical imbalance' theory has long been insufficient

E.g. Antidepressants boost brain chemical levels pretty much immediately. But even the best ADs take 2-3 weeks before they help. If depression was purely a matter of chemical imbalance, they'd work right away.

/4

In hindsight, the idea that something as complex as a prolonged mood disorder could be thoroughly explained by something so simple as 'not enough of a certain chemical' seems wildly naïve, and really doesn't acknowledge how incredibly complicated our brains are

/5

In a way, looking at how antidepressants work and saying 'ah, depression must be caused by not enough of that brain chemical' is like concluding that headaches are caused by 'not enough paracetamol'.

It's not that paracetamol doesn't help, but there's a LOT more to it

/6

We're still getting to grips with what the serotonin system in our brains does and what it's for. Even just recently, whole new branches of it have been uncovered. But a lot of evidence suggests it's a big part of mood regulation. As in, it helps control/change mood

/7

So, logically, if you increase the availability of serotonin in the brain, it should make the brain *more capable* of changing mood. But it doesn't necessary mean you'll be in a better, happier mood. Hence SSRI's are hardly ever used 'recreationally'.

/8

But more recent evidence suggests that there are at least two serotonin systems in the brain, one that helps elevate mood, one that lowers it.

SSRI antidepressants could easily work on both, to different degrees in individuals. Hence some find ADs make them feel *worse*

/9

There's so much more to it than even this, this is just a tiny snippet of the vast tapestry that is our understanding of how brains produce mood and the interplay with chemical factors that interact with it

So yeah, 'chemical imbalance' doesn't even start to do it justice

/10

So why did the 'chemical imbalance' idea of depression become so widespread, and entrenched?

Lots of reasons. One is that it's *because* it's so simple. It reduces a big, complex, even scary problem, to a very simple mechanism that, ostensibly, nobody is to blame for

/11

So if you want to explain depression in a judgement free way that most people can easily grasp, saying it's a 'chemical imbalance' is a good way of doing that.

Doesn't make it correct, of course. But even so.

/12

You can also see, in a time when #MentalHealth issues were far more unknown, scary, and stigmatised than they are now, saying your disorder is a 'chemical imbalance' could be very reassuring, to yourself and others. It's a biological issue, something tangible and blame-free

/13

But the widespread acceptance of the 'chemical imbalance' theory of depression, while understandable, has had a lot of downsides.

First and foremost, it's wrong. Or at least a huge oversimplification. So people's understanding of depression, derived from it, will be flawed

/14

And as someone who's 15 tweets in to a long thread about just how complex depression and neurotransmitters are, I obviously feel it's important to ensure people have as thorough an understanding of such issues as possible, no matter how complex it is. This stuff's important

/15

But there's a grimmer side to the 'chemical imbalance' thing too

One issue with mental healthcare has been over-reliance on the 'medical' or 'disease' model of mental illness. That's changed in recent years, but it's still an issue that needs adressing.

/16

Put simply, the medical model of mental illness argues that mental disorders should be treated like physical ailments; by addressing the underlying biological problem that's causing it. This is, ultimately, what most medical doctors are trained to do, after all.

/17

This may make sense in theory, but the issue is that mental health problems typically *aren't* the same as physical health issues. They don't really have 'cures' or fixes in the same way, for one

(Not that every physical illness has such things by any means)

/18

But a key problem in the medical model is that it establishes a very one-sided patient-doctor relationship. The former must be very passive, just doing what they're told by the latter, and waiting for the treatment to work

/19

This isn't how mental health disorders should be treated in most cases. As they occur largely within the individuals own mind, expecting that individual to just be quiet and do as they're told isn't a good approach. It can actively backfire.

/20

The nature of the patient-doctor relationship in mental healthcare is a whole other discussion, but ultimately, insisting that depression is purely a 'chemical imbalance' further reduces the individuals agency, by reducing it to a biological matter they've no control over

/21

So yeah, depression being a simple 'chemical imbalance' is a claim that should be put to bed. It's long been proven invalid.

The issue is, it's a very short leap from there to '...so that means antidepressants don't work/are useless'. And that would also be wrong.

/22

Ultimately, the effects of antidepressants remain incompletely understood. But that doesn't mean there aren't any. But while they do reliably increase neurotransmitter levels in the brain, that doesn't mean that's all depression is caused by.

/23

I actually explain this exact issue in far more detail in my latest book Psycho-Logical, if anyone's interested.

amazon.co.uk/Psycho-Logical…

In any case, apologies for the absurdly long thread. But then, it's an absurdly complex issue. Amazed I can effectively tweet it at all

/end

Thread from earlier about the new study saying #depression is not due to a chemical/serotonin 'imbalance'

In short; yes, but that doesn't change nearly as much as many people seem to think it will

#MentalHealth #Antidepressants #Brains

https://twitter.com/garwboy/status/1549743557845651457

Also worth flagging up:

This article, by those behind the study, ends with some, IMO, unjustifiably nagative conclusions about the efficacy of antidepressants.

This suggests an ideological opposition, which casts doubt on everything else, unfortunately

theconversation.com/depression-is-…