Mental health

Is Oversimplification of Mental Illness Useful?

Mental health @ Home - Depression isn't technically a chemical imbalance - drawing of brain hemispheres

We’ve all heard of the “chemical imbalance” explanation for mental illness.  This terminology has served a purpose in making the argument that mental illness is actually an illness.  However, it is a gross simplification of mental illness in terms of what’s actually going on in the brain.  Lately, I’ve read criticism of the chemical imbalance idea as being inaccurate, which makes me wonder if it’s terminology that’s no longer serving us.  I’m going to focus on depression, as it’s probably the condition for which I’ve seen the chemical imbalance idea challenged the most.

This chemical imbalance theory arose in the 1960’s, when it was hypothesized that a deficit in serotonin caused depression.  According to Wikipedia, it began with observations with the drugs reserpine and isoniazid, and the way they affected monoamine neurotransmitters (the monoamines include serotonin, norepinephrine, and dopamine).  The serotonin hypothesis fuelled further research and the development of new serotonergic drugs.  These drugs proved to be effective, which reinforced the hypothesis. “Chemical imbalance” certainly captures the state of scientific understanding 50 years ago, but we’ve come a long way since then.

Now it’s generally recognized that the etiology of depression is complex and multi-factorial, and the idea of a simple serotonin deficit is inaccurate.  In many ways, the more the science has progressed the more we realize just how much we don’t know.  A few of the biological factors that have been implicated are:

  • Signalling between neurons via monoamine neurotransmitters (serotonin, norepinephrine, and dopamine): This is much more complex than absolute amounts of these neurotransmitters.  Regulation of neurotransmitter receptors and transporters on nerve cell membranes has a major impact on signal conduction.  It’s been suggested that the delayed onset of action of antidepressants may be related to the time it takes to adapt the regulation of these receptors via changes in the expression of genes encoding for them.
  • Glutamate:  It is thought that the neurotransmitter glutamate can cause what’s referred to as “excitotoxicity”.  Inflammation is one of the factors suspected to play a role in promoting glutamate excitotoxicity, mediated by various factors including microglial cells.   Ketamine affects the glutamate signalling system via its effect on NMDA receptors.
  • Genetic factors: Genetic variants affecting such things as serotonin transporters and methylation processes are thought to potentially play a role.  Variants in the SERT (serotonin transporter) gene are associated with different patterns of response to treatment than those with the “normal” SERT gene.  Significantly more research is needed in this area to gain a greater understanding of the role of genetics.
  • Epigenetic changes:  Epigenetics refers to when and how often our genes are translated into the proteins that they code for.  A wide variety of environmental factors are thought to affect this, and this is where adverse childhood experiences can have a huge impact.  There is still much, much more to be learned in this area.

Sometimes people will argue that depression is not biologically caused, but instead is caused by psychosocial factors including trauma.  I guess the problem I have with this is that it strikes me as another oversimplification of mental illness.  David Karp is a remarkable author and sociologist who has written about his own experiences with depression.  He argues that purely social determinism is just as problematic as biological determinism when it comes to depression.

I’m inclined to think that at this stage of the game “chemical imbalance” has outlived its usefulness.  In a time when it’s so easy for people to look things up, if we’re using terminology that oversimplifies to the point that it’s not really accurate, we may just be shooting ourselves in the foot by hanging onto this kind of language.  I’m not sure what would work better.  I could suggest “complex, multifactorial, biopsychosocial illness” but that’s rather long-winded.

What do you think is the best way to characterize mental illness?

Note: There are a couple of good papers by Albert and Benkelfat looking at where things stand now in relation to the serotonin deficit hypothesis; these are available from the National Institutes of Health here and here.

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Making Sense of Psychiatric Diagnosis breaks down the different categories of DSM-5 diagnoses, explaining the diagnostic criteria and providing first-hand stories of the various illnesses.  It’s available on Amazon and other online retailers, as well as the MH@H Store.

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23 thoughts on “Is Oversimplification of Mental Illness Useful?”

    1. All in our head, as if there were nothing in there rather than that little old brain that is far more powerful than any computer anyone’s ever been able to come up with…

  1. i do think the argument is a little outdated. but i also believe that in some mental illnesses, like depression, there definitely is a chemical imbalance in the brain. xo

    1. Yes, there’s definitely a biological element. I’d just like to see a new description that describes it a little more accurately than chemical imbalance. I worry that people may fixate on chemical imbalance being somewhat inaccurate and then throw the baby out with the bathwater by denying that there is a biological cause. xo

  2. I agree with this, it’s extremely hard for the population to get a grip of mental illness when it is constantly being oversimplified to the point where it doesn’t really correlate with the reality of most people’s lived experiences. Yet people seem to switch off if the conversations about it become too complex. So I guess a balance is needed? Or different explanations in different contexts? I quite like your definition to be honest haha xx

  3. Oh, right. I remember studying “biopsychosocial” factors in college!! I think depression could be a combination of: brain chemistry, negative cognitive schemas, exposure to others’ despressed ways of being (modeling our parents, for example), reaction to trauma–most definitely, childhood abuse, seasonal affective issues, hormonal issues (postpartum, PMS, menopause, ovulation–you name it), and other things that aren’t coming to mind right now. Unfortunately, the oversimplification of small minds goes like this: “You’re not depressed. Get over it already.” GROAN!

    I think it’s great to intuit which of the above factors are contributing, because then you can treat it accordingly. If the issue is hormones, it might be worth it to see a gyno and take birth control for off-label purposes. If it’s cognitive issues, then you could point to yourself in the mirror and say, “Hot damn, you’re sexy.” (This exercise can have surprising results–even laughter is a good response here!)

    Great blogging!!!

    1. Thanks 🙂 It’s definitely a problem in this world that anything much more complicated than 1+1=2 is more than a lot of people are able/willing to understand.

  4. I used to be really depressed when I was younger because I was living in a magical world. I left the real world behind for a music-fueled fantasy world, and it took me years to pull myself out of it. It’s hard to say exactly what caused it beyond my horrible childhood and an unquenchable desire to be loved by the people around me (my friends). That was when I was a teenager.

    A bit later, after college, I worked at a friendly place teaching kids to read. I was depressed there, too, because I felt left out of my coworkers’ inner circle. (They’d have conversations around me without meeting my eyes.) Gotta say the best cure for that was going on disability and not working anymore! Yeah, depression can be complex and multifaceted and as difficult as its base cause to cure.

  5. This is a very interesting topic! I didn’t know a whole lot about it since I’m not currently involved with a psychiatrist. Always important to remember there may be a biological component too and not as simple as assumed. Thank you for sharing!

  6. The truth of the matter is people are self centered. I don’t mean selfish. I mean focused on the demands of their own lives. My own dad has had cancer 4 times in 10 years and I still barely know what cancer is let alone what non- hodgekins lymphoma is. As long as health care is over simplified mental health will be too. Just like when someone is sick you say they’ve got the flu and don’t list symptoms or complications and we are in a society where when asked how are you all we say is fine.

  7. All the UK mental health charities do not use the chemical imbalance reason . Mind for example clearly state that this is not true, it’s come from the misunderstanding that as antidepressants influence brain chemistry then therefore it must be a chemical imbalance. The truth is we don’t really know why AD help. Being clear I am not saying there isn’t chemistry at work ( there is) just like genes, social and economic circumstances, life experiences all play a part- in essence we don’t fully understand. Which is the true complexity and why each person needs to be treated individually . What works for me may not work for you. That is where simple explanations or reasons fall down and make it so hard to explain to people who haven’t experienced it. Unfortunately it also adds to the stigma, especially around AD, where we really do not have the right research or studies, which leads to some professionals seeing medication as good, some as evil. So just like the illness is complex, the treatment is complex…which makes it harder and longer to treat. Whatever the factors that contribute to it, it is an illness, the seriousness of which people shouldn’t underestimate nor be ashamed to seek help, including medication. This is such a big topic! Chris

  8. My depression has always been triggered by psychosocial factors but surely there has to be an underlying cause within the brain that allows those factors to trigger it. Not everyone who has cancer will get depression, a high proportion will but not all, is this because they have better social means to deal with it, is it due to personality or biology? Nature or nurture? So many unanswered questions.
    Great post x

  9. I’m guilty of oversimplifying. I refer to bipolar as a “brain disorder”. The world lacks the proper words for describing MI, because as you point out the biology of it isn’t understood yet. I have hopes that one day they will actually figure it out, at which point I believe the stigma will get better once it is proven that it’s physical.

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