Causes of Psychological Disorders

June 4, 2012 5:51 PM

I am working in a Autism lab this summer. I've been wondering whether it is a problem that so many psychological disorders are defined by symptoms and focused on treating symptoms. I think, and this isn't a particularly controversial opinion, that it is also important to investigate their causes. Are there any instances of really effective investigations of the cause/causes of psychological disorders (discussion open to any disorder)?
posted by Lee Shore to science & nature (19 answers total)

I used to hang out on alternative med sites and I have 2 ASD sons. I have been told that 75% to 80% of ASD kids improve if treated for metal poisoning, which typically involves a multipronged approach to also give supplements, treat yeast, and typically also treat infction. My sons improved with treatment of underlying health issues, not metal poisoning per se but many of the other issues (nutrient deficiencies, yeast, etc). I think a lot of mental health issues have an underlying physical health component.
posted by Michele in California at 5:58 PM on June 4, 2012

You're on the side of the angels. Everyone would really love to treat causes -- but no one knows what they are.
posted by Chocolate Pickle at 5:59 PM on June 4, 2012 [5 favorites]

First off, autism is not a psychological disorder. It's a neurological disorder and the reason its symptoms are treated is because no one knows definititively what the root cause of autism and other spectrum disorders is. Empirical evidence in this area is, if I'm not mistaken, subsequently highly debated and still in constant flux.
posted by These Birds of a Feather at 6:00 PM on June 4, 2012 [15 favorites]

"Cause/causes of psychological disorders" is highly vague and varied (do you mean neurotransmitter imbalances? do you mean emotional trauma? do you mean physical trauma to the brain? do you mean naturally-occurring physical brain structure differences? do you mean poor coping skills? do you mean chronic life stress? do you mean general medical conditions? do you mean substance use? do you mean breakups? do you mean loss and grief? ... see what I mean?).

Some of the research on trauma might be interesting to you, because the symptoms of trauma are pretty complex but the effect of emotional trauma is pretty direct. Other than that, you need to be a little more specific in your question.
posted by so_gracefully at 6:01 PM on June 4, 2012 [3 favorites]

True, Autism is a neurological disorder. What I'm asking about is the neurological causes of disorders that I'm putting under the umbrella of "psychological disorders". (I mean disorders in the DSM.) I realize that "causes" aren't always only neurological; and my question is really broad, I'm interested in a variety of responses. These things being said, are there any particularly interesting studies or methods used to dig deeper than symptoms?
posted by Lee Shore at 6:06 PM on June 4, 2012

There's a hell of a lot of that going on, but right now it's almost all highly preliminary. There isn't much in the way of results that is even suggestive, let alone definitive.

One of the few areas where there are answers now is in cause and treatment of Parkinson's disease, and a lot of progress is being made there. But those lessons don't map to the other kinds of disorders you're talking about.
posted by Chocolate Pickle at 6:16 PM on June 4, 2012

Yes. For example this very recent paper and this somewhat older one on rat anxiety that I just happen to remember. My understanding is that lots of people similarly are working / have worked on the genetic, neuron-structural, and developmental pathways of ASD. I understand a hot thing right now in autism research is using induced iPS to neurons to experiment with developmental parameters from autistic individuals.

Get ahold of the lit review sections of theses coming out of the lab you're working with (or grant applications) for background on the disease you're studying. If you work with a clinical lab, find a bench lab that studies the same thing.
posted by a robot made out of meat at 6:21 PM on June 4, 2012

Another disorder where there's been a lot of progress is epilepsy. It's pretty well understood now, and clinical treatment is straightforward and effective. (I don't think anyone yet knows why any given individual is prone to epilepsy, but they know what's going on in the brain of an epileptic, and they know how to prevent seizures.)
posted by Chocolate Pickle at 6:21 PM on June 4, 2012

I subscribe to email alerts for Nature's journal 'Molecular Psychiatry.' The kind of research in this journal is exactly what you're looking for. I'd link but I'm on my phone and lazy ATM.
posted by sunnichka at 6:25 PM on June 4, 2012

Of course there is research into the causes of autism. You might want to start by following the Autism Science Foundation blog and the Simons Foundation.
posted by lakeroon at 6:51 PM on June 4, 2012

Here's some food for thought (from last month's Nature Reviews Neuroscience).

Impaired mitochondrial function in psychiatric disorders


Also, regarding ASD, here's a link to an overview of some recent papers that just came out about ASD genetics.

Neurogenetics: Unravelling the genetics of autism

Pubmed some review papers on the underlying genetics and physiology on any psychiatric disorder and you will find lots to read...
posted by scalespace at 7:10 PM on June 4, 2012 [1 favorite]

whether it is a problem that so many psychological disorders are defined by symptoms

This is a HUGE problem in actually discovering a "cause" of a psychological disease. Moreover, the problem is that so many psychological disorders are defined by SUBJECTIVE symptoms. It is hard enough to know how some traits with objective symptoms (e.g. seizures, tumors) are caused. 70% of the people with a certain tumor type might have a mutation in gene A, but 30% don't....but 90% of THAT group had a mutation in gene B and also live near a radioactive treatment facility, or SOMETHING.... but when it comes to psychiatric disorders (not to be confused with neurological disorders like epilepsy) you need to now hunt for potential causes without even having an OBJECTIVE standard.

What "causes" anxiety may be difficult to find when some people with anxiety disorder just consider themselves experiencing normal worries and don't bother seeking treatment/testing, while others who are just worried about normal day to day things believe it's anxiety and seek treatment for that.

Autism is similar, especially when it comes to socialization. Autism is a severe disorder....however people with poor social skills often label themselves as having ASD, sometimes because it gives them an excuse to continue with bad behavior, or not feel guilty about not being as extroverted as everyone else (again, I'm saying SOME people....including me - a friend of mine has maintained for years that I've ASD.... but I believe it's more simple introversion).

....ANYWAY, my point is, if these people and their friends are mislabeling themselves as "autistic" (or anxious, or depressed), scientists include them in the groups that they are studying with people with the REAL disorder, and it obviously becomes that much harder to find a common "cause" of the disorder (since some people don't actually have the disorder!).

People are definitely looking for "causes", but subjective symptoms makes its very difficult to find them in an effective manner.

I do believe I read recently that some "autistic" babies/toddlers have brains almost twice the size of non-autistic peers, so it could be a matter of improper cell division.... but, as one posted mentions above, some individuals with metal poisoning are misclassified as autistic - if these individuals have "normal" sized brains but are labeled as autistic, the research of brain size might be shelved.
posted by Lt. Bunny Wigglesworth at 7:10 PM on June 4, 2012

As others have linked above, there are lots of studies being done to try to determine the proximate and ultimate causes of neurological disorders, but it's difficult for ethical and practical reasons.

Part of the trouble with looking for "causes" of disorders is that you can't ethically test a hypothesis of "X causes autism" for any X or any other disorder. You can look for correlations, like "80% of people exposed to X have the disorder, while only 3% of the general population has the disorder," but that still doesn't prove that X causes the disorder. To prove causation, you'd have to take 2 groups of normal people, randomly choose half of them, and expose them to X to see if they develop the disorder. Not ethical.

So people can study things like MRIs or fMRIs to look for changes in structure or blood flow in the brain, or autopsy reports to see firsthand what structural changes might be present. These can provide clues to the anatomical and physiological basis for some kinds of disorders, but they have their own limitations. MRI requires that you remain quite still in a very loud, very confined space for a lot longer than any 5-year-old (or honestly a lot of 40-year-olds) can handle without being drugged up, which is not something people generally want to do to kids. Autopsy obviously requires that someone be dead already.

Animal testing seems to be the way to go, but this requires the development of useful animal models of the disorders, i.e. you have to have autistic mice if you want to use mice to test your theories about autism. And even if you can do those tests, they may or may not apply to humans.
posted by vytae at 7:31 PM on June 4, 2012

There's also the question of definition - what was manic depression is now bipolar I and II and NOS and cyclothymia, and you can have bipolar I without ever being depressed, and so forth.

We're still back at "well, we're pretty sure that this disease has something to do with neurotransmitters, and umm, electric current... oh, or we could block a receptor... that doesn't explain why so many of them are also anxious though..." Until you've properly defined what's actually happening, figuring out the root causes and fixing them is like shooting in the dark with earplugs in.

(We've come a really long way in the last 40 years in this area, though, so yay.)
posted by SMPA at 7:40 PM on June 4, 2012

This is the driving force behind a lot of the research in mental health and developmental disability. The responses above touch on a lot of the issues we have, but I swear we're working on it (biased as an ASD/developmental disability researcher myself).

As a lot of people pointed out there are a myriad of reasons that this is complicated:

1) The disorders you are talking about are often characterized based on behavior. There are not blood tests, x-rays, etc. available to make these diagnoses, so we do the best we can by carefully observing behavior, characterizing what we see and developing categories to capture what we see in the ways that make the most sense. I think you would probably agree that autism is a real phenomenon that you can recognize when you see it. At the same time, each person with an autism spectrum disorder presents with very individualized characteristics. This leaves us with some diagnostic question in some places. Does someone with Aspergers syndrome have the same characteristics in a meaningful way as someone with Autism? This is open to a huge amount of debate. If we're not capturing the same things with our diagnostic categories, it can be nearly impossible to be sure that we're studying the same things, let alone are likely to find a unifying underlying cause.

2) There are very few diagnosable conditions that have a single "cause." Think about something that is a purely medical diagnosis, like heart disease or cancer. There are genetic factors that make an individual more susceptible to developing the condition, but don't guarantee that you will. There are environmental factors like diet, smoking, exposure to toxins in the environment that make it more likely that you will develop the condition. Even for these medical disorders, we don't know exactly all the genetic factors, how different genes interact with each other, how much of each environmental factor you need to develop the condition. So say you were to have all this information available about a given individual. You would still not be able to say for sure if that person will develop that condition. Now multiply that complexity by a factor of thousands to account for the extremely indirect relationship between genes and behavior, and you start to get an idea of why we don't yet know causes for these things. There are some really impressive studies working on this. Google "Baby Sibs" or the ERLI project for autism and you'll get a sample of some pretty ambitious work looking at these things.

3) The technology we have to study this is still developing. Think of early telescopes. What could Galaleo really see and know about heavenly bodies. Not a lot in comparison to what we can see now, right? A similar thing is happening with methods to study the brain. A lot of what we are talking about as signs/symptoms of these conditions happen on a microscopic or even smaller scale. We can't detect these kinds of changes with MRIs and similar technologies. A lot of what we talk about as "causes" (like an over development of local neural connections with fewer longer distance, integrating connections in the brain) is something that we've seen at autopsy. We can observe it more directly with animal models, but mice and rats are nowhere near as complex as humans are, so we're limited in what we can extrapolate from there.

4) Whether or not we know the cause, we do know of interventions that are helpful and have a huge benefit right now. Things like providing early intervention, developing language, providing social skills support, etc. are all effective. There is not really a need to wait to intervene while we look for causes. We can work on both simultaneously.

I'd also like to just leave you with a word of caution. A lot of folks on the spectrum, and a lot of folks who care about them don't necessarily want a "cure" or to find a cause that would lead to one. There is a huge neurodiversity movement that argues that to an extent this is simply a different way of experiencing and relating to the world that is no more or less valid than "neurotypical." It's similar to earlier movements in the Deaf community that very correctly pointed out that Deafness is a culture, and is not necessarily in need of a cure. This isn't to say that there are not challenges that individuals on the spectrum face, and that intervention is not beneficial. It is. I just want you to know that others may feel offended by discussion of "cure" for this particular population.

So that is an extremely long-winded answer to your question, but I hope it's helpful. I'd be happy to talk more by meMail if you have other questions. I think you're going to enjoy your experience. You're already asking the big questions. You are also working with a community of great people (ASD individuals and their families). Best of luck to you and I hope you are a driving force in answering some of these questions in the future.
posted by goggie at 8:01 PM on June 4, 2012 [4 favorites]

I have no expertise on autism or medical research, but I would like to point out that there are a number of strictly physical disorders that are diagnosed by symptoms and treated entirely by managing symptoms. Genetic disorders in particular are diagnosed because the patient has symptoms that resemble the symptoms of other patients. It's very imprecise and depends on finding a doctor that recognizes a symptom. Even then, a neurologist might call it one thing, a dermatologist might have a different name, and a geneticist might call it yet something else. There are diagnostic tests for some of the more common disorders (although not always very reliable at this point), but there's no testing for much of the really rare stuff and isn't likely to be for a good long time. There certainly is research happening, but since understanding mutations that happened in utero isn't likely to help existing patients much, research focusing on the management of the symptoms is by far the best way to help patients currently suffering from these syndromes.
posted by Dojie at 8:07 PM on June 4, 2012

There are a ton of papers addressing the relationship of genetics and autism. I don't have any papers handy at the moment but these are a few from the top of my head that you might find interesting.

Kjelgaard, M. and Tager-Flusberg, H. (2001). An investigation of language impairment in autism: implications for genetic subgroups. Lang Cogn Process. 16(2-3): 287–308.

Muhle, R., Trentacoste, S., and Rapin, I. The genetics of autism. Pediatrics 113(5): 472-486.

Rice, M., Smith, S., and Gayan, J. (2009). Convergent genetic linkage and associations to language, speech and reading measures in families of probands with Specific Language Impairment. J Neurodevelop Disord. 1:264–282.

Bishop, DVM (2010). Overlaps between autism and language impairment: phenomimicry or shared etiology? Behav Genet. 40(5): 618-629.

Trouton et al. have a paper [Trouton, A., Spinath, F., and Plomin, R. Twins Early Development Study (TEDS): a multivariate, longitudinal genetic investigation of language, cognition and behavioral problems in childhood. Twin Research. 5: 444-448.] about the Twins Early Development Study (TEDS) which has been used to examine familial inheritance of autism and language delay among other neurodevelopmental disorders. There are many other papers that discuss the TEDS.

Bishop, DVM (2009). Genes, cognition, and communication: insights from neurodevelopmental disorders.Ann N Y Acad Sci. 1156(1): 1–18.

I'm pretty sure there's been some discussion about the role chromosome 7 plays in the development of neuropsychological disorders like ASD and SLI. [See Folstein, S. and Mankoski, R. (2000). Chromosome 7q: where autism meets language disorder? Am J Hum Genet. 67(2): 278–281.]

The KE family research is pretty interesting, but I believe that their inherited FOXP2 mutation is thought to be specific to their family and not implicated in language disorders in the broader population.

Gopnik, Tager-Flusberg, Folstein, Bishop, and Rice are all good authors to browse if you're interested in autism/ASD specifically. If you want more recommendations, I can pass some along when I get to work tomorrow.
posted by easy, lucky, free at 8:21 PM on June 4, 2012 [1 favorite]

Also, the reason ASD in particular is described by symptoms rather than causes is that currently the diagnostic tests look for particular behaviors associated with ASD, not for a specific mutation or anything like that. The ADOS, for example, is widely used and is based solely on an examiner's observations of a child's social interaction. The ADI-R is sort of the same idea, but the parent is the one making the behavioral observations.
posted by easy, lucky, free at 8:25 PM on June 4, 2012

Here's the journal: Molecular Psychiatry
posted by sunnichka at 12:18 AM on June 5, 2012