I think about Ted Chiang’s Anxiety is the Dizziness of Freedom a lot. It’s a short story which can be read in a sitting. Do check it out, before going further. This post will contain spoilers and, to be frank, your precious time is better spent with him than me.
The plot is based on the many worlds interpretation of quantum mechanics. Parallel universes exist and can be created by devices called prisms (plaga interworld signalling mechanism) which split a timeline in two. Each branching world can then communicate with the other through the prism. As you might expect, each timeline develops differently (partly due to random events) and over time they diverge further apart.
In each branching world there will be parallel versions of you (paraselves). Naturally, some people struggle to deal with the thought of their paraselves taking different trajectories. There will be timelines in which you got that job, or decided to move city. Or got out of that toxic relationship. Chance decisions can lead to big changes. Which paraself will living your best life?
One strand of the story particularly resonated with me. A therapist, Dana, regrets a decision she made as a teenager. On a school trip, she and a friend Vinessa smuggled in a supply of drugs. When they are caught, rather than take the blame, she points the finger at Vinessa. From that moment on, Vinessa’s life takes a bad turn. She is suspended from school and spirals out of control.
Angry at the world, she began acting out: shoplifting, staying out all night, coming to school drunk or stoned, and hanging out with kids who did the same. Her grades plummeted, and her chances of getting into a good college vanished. It was as if, before that night, Vinessa had been balanced on a knife’s edge; she could have become either what society considered a good girl or a bad girl. Dana’s lie had pushed her off the edge, onto the side of being bad, and with that label the course of Vinessa’s life had taken a different direction.
When they meet again later in life, Vinessa has been in and out of rehab. From a place of guilt, Dana funds her various endeavours - college tuition, business ventures - none of which bring success. By blaming Vinessa on that school trip she created a self-fulfilling prophecy, for which Dana will forever be in debt.
Life-events in childhood or adolescence can indeed have far-reaching consequences. Often, patients look for the root cause of their distress. How should we think about that?
Root causes
I hear about root causes all the time. Sometimes in the context of psychiatric treatments and their limitations. This Telegraph article is a good example:
I always say to my patients that a pill isn’t going to be the thing that fixes the problem. It very much depends on how severe someone’s symptoms are, but really you want to get to the root cause of why they are struggling with their mental health,
I hear it from patients too. They might be reluctant to take medication, which they see as a sticking plaster rather than addressing the crux of their problems. Explanations of mental disorders can feel inadequate if they don’t identify the deep, underlying reason a person is struggling. Rose Cartwright describes the lack of clear biological markers for her OCD.
How could my illness be like any other, but not definable or testable? It was in this cognitive dissonance that I found myself on a TV shoot, sitting halfway up a spiral staircase, caught between fact and fiction. As I watched my old story being enacted around me, the pressure of a new and much scarier story was starting to build. If illness wasn’t the root cause of my suffering, what was?
The search for root causes often means a life event that has triggered the mental disorder. When I hear people talk about root causes, it usually means they are not happy with a biological explanation and want something more psychological, more meaningful, more profound.
In clinical practice, this is tricky though - we can rarely, if ever, put our finger on a singular cause for a mental disorder. This is the case for biological causes but for life events too.
Chemical imbalance
Have you heard of depression being caused by a chemical imbalance in the brain? This rather outdated and often mischaracterised theory has generated controversy in recent years. The debate was reignited by Joanna Moncrieff, a critical psychiatrist, who published a review showing a lack of evidence for low levels of the neurotransmitter serotonin being responsible for depression. The review’s methodology and interpretation were criticised by prominent biological psychiatrists, however, I think most psychiatrists would agree that depression isn’t merely caused by inadequate levels of serotonin. It is, of course, much more complex.
Most psychiatrists also agree that antidepressants just work. We know this empirically from meta-analyses of many randomised controlled trials. Whether they are correcting some underlying chemical imbalance is of secondary importance. Moncrieff argues that, since antidepressants aren’t correcting a deficiency in serotonin, it is impossible to say that taking SSRI antidepressants is worthwhile, or even completely safe.
I think this is the wrong way to look at both mental disorders and their treatments. These are problems with multiple causes and no one biological abnormality that needs to be corrected. Our current view of psychiatric genetics illustrates this nicely.
Genetics
Genes are our blueprint. Unlike other biological explanations, they are as upstream to mental disorders as you can get. Illnesses like schizophrenia have a strong genetic component; the heritability (meaning the variation in the population than can be attributed to genetic factors) is a whopping 80%.
So are genes the root cause of schizophrenia? Not so fast. The risk for schizophrenia is spread across many genetic markers - we’re talking hundreds. Each one confers a tiny risk for the disorder. Like every complex disease, schizophrenia is polygenetic. Each of us will carry a number of the genetic markers that are associated with the disorder. We can take an aggregate of the risk genes for schizophrenia - the polygenic risk score - but even then, it isn’t accurate enough to diagnose the disorder and hasn’t impacted routine clinical practice.
At best, genetics provides a predisposition for psychiatric disorders like schizophrenia. Although they are at the root of our biology, we don’t really think of genes as the ground-truth. Genes are not destiny.
Drugs
Using certain drugs seem to increase the use of specific psychiatric disorders. Cannabis in particular is associated with the development of psychosis. Giving high doses of THC (an active component of cannabis) to healthy people in the lab reliably reproduces psychotic symptoms. Drug-induced psychotic episodes are a common encounter in the emergency department, and almost a third of these people will be diagnosed with schizophrenia at six months.
For those who develop a transient psychotic episode in response to a drug, I guess that substance could be thought of as the root cause. But this also doesn’t feel quite right. After all, many more people will use the drug and not develop severe mental disorder. For those with a predisposition for developing psychosis, could cannabis use at a critical time in their development be the root cause of their illness? Might they have gone on to become unwell later in life, perhaps triggered by something else? These questions are difficult, if not impossible to answer for any individual.
Drugs as acting as a trigger for mental illnesses in those who have a susceptibility is similar to how I think of trauma.
Trauma
Now we’re getting into what people really think of root causes - they’re not looking for a gene or a drug that caused their illness, they really mean something that happened in childhood. Indeed, these are well studied risk factor for a range of mental disorders - a 2021 analysis found there was a 3x odds of developing a mental illness in those exposed to multiple forms of maltreatment.
Of course, there are lots of potential confounders between childhood trauma and mental illness (it tends to be accompanied by other forms of adversity, like poverty). One way around this is to use quasi-experimental designs (such as twin studies). When restricted to these more stringent studies, the association was smaller but was more likely to be causal.
Unfortunately, childhood adversity is a relatively common risk factor and thankfully not everyone goes on to develop a disorder. On the other hand, many people with a mental illness do not have a history of trauma. I think this points again to risk factors interacting with an individual’s vulnerability for mental illness.
Even a disorder defined by response to trauma, PTSD, has a genetic component - in this case, is trauma the root cause, or the genes that predisposed a reaction?
Different versions of you
Mental disorders are complex diseases. They have multiple genetic and environmental risk factors, each exerting a small effect. In most cases a definitive underlying cause will never be found. This goes for both biological and psychological factors.
What if you could run back time and see what happens if different versions of you experience different life events. Would life have turned out differently?
Major spoilers follow
In Ted Chiang’s story, Dana is given a host of prisms. She uses them to communicate with paraselves who recount that fateful day she and Vinessa were caught with drugs.
One version of Dana describes the incident:
“Ms. Archer came into our room and found us counting the pills. She asked us what was going on, and for a second I froze. Then I said they were mine, that Vinessa hadn’t known anything about them. She was suspicious, because I’d never been in trouble before, but I convinced her. Eventually I got suspended from school, but it didn’t turn into as big a deal as it could have; they put me on probation, so if I stayed out of trouble, it wouldn’t go on my permanent record. I knew it would have been much worse for Vinessa because of the way the teachers felt about her.
“But Vinessa started avoiding me, and when I finally asked her why, she told me she felt guilty every time she saw me. I told her she didn’t have to feel guilty and that I wanted to hang out with her, but she said I was just making it worse. I got angry at her; she got angry at me. She started spending time with these other girls who were constantly getting into trouble, and everything went downhill from there. She was caught dealing on school grounds, she was expelled, and she was in and out of jail all the time after that.
“And I keep thinking, if I hadn’t said the pills were mine, everything would be different. If I had let Vinessa take her share of the blame, there wouldn’t have been that wedge to drive us apart. We would have been in it together, she wouldn’t have started hanging out with those troubled girls, and her life would have gone in a completely different direction.”
Another states:
“One of the teachers came into our room just as we were counting the pills. I confessed everything immediately; I told her that Vinessa and I had stolen them from our parents so we could have a party. Eventually the school suspended us and put us on probation; I think they wanted to do something worse to Vinessa, but they had to punish us both equally.
“Vinessa was furious at me. She said I should have told the teacher we just found the pills, that someone must have slipped them into our bag at the airport, and we were about to tell a teacher about them. She said they wouldn’t have been able to pin anything on us. But because I had confessed, she was on probation and the teachers who hated her could take her down at any time. She wasn’t going to give them that power over her. As soon as our suspensions were over, Vinessa came into school drunk. After she did that a few times, the school expelled her, and she started getting arrested.
“And I keep thinking, if only I hadn’t confessed, everything would be different. That close call would have been enough to warn Vinessa away from getting into real trouble. She only started acting out because she was angry at me. If it weren’t for that, she would have gotten into a good college, and her life would have gone in a completely different direction.”
Chiang sums up:
The other videos made no mention about being caught with the pills, but they still followed a recognisable pattern. In one, Dana felt guilty about introducing Vinessa to a boy who got her addicted to drugs. In another, it was a successful shoplifting incident that emboldened Vinessa to attempt more dramatic thefts. All these Vinessas getting stuck in patterns of self-destructive behavior. All these Danas blaming themselves for it, no matter what actions they took.
None of us have the luxury of rewinding the clock or finding versions of ourselves who have taken other paths. Even if we could, what seems like a fork in the road may still end in the same destination.
We seek deep, profound meaning at the heart of mental illness. But in truth, for most people, there is no ‘root cause’.
Agree that we need to move away from a binary "root cause" of mental illness that seems to pervade society, patients, and even amongst some of our colleagues! You bring up chemical imbalance, genetics, drugs, and trauma all being potential causes - is this not just really Engel's biopsychosocial model? :)
I see the biopsychosocial model as the antithesis to "root cause" question and use this model everyday in my own clinical practice. I often may spend a significant chunk of my consult time explaining to my patients the distress they have is through a complex interplay of these 3 factors, and some factors may have more weighting than others (for some patients, "depression" is 90% psychosocial and 10% biological, and others vice versa).
A thoughtful biopsychosocial formulation is often more validating than a simple biomedical explanation ("you don't make enough serotonin"). This takes a lot more time and effort for the psychiatrist though, and as a consequence, uptake and use seems to vary significantly between psychiatrists in different jurisdictions. @Awais Aftab also had a similar post about the hermeneutic silence that is occurring in our clinics when we don't have a more nuanced conversation about the source of psychiatric symptoms (whether or not a patient accepts this nuance is another question!)
I'm curious in UK psychiatry training how much emphasis is placed on learning and practicing biopsychosocial formulation? It is emphasized quite heavily here in Canada where I trained, and part of our Royal College examinations and residency training.