4 ms·

"It's clear a history of trauma of various sorts increases the risks of developing mental illness, but nobody can say with much certainty if there are genetic p

by dbspin 4y ago

"It's clear a history of trauma of various sorts increases the risks of developing mental illness, but nobody can say with much certainty if there are genetic predispositions or not." This isn't accurate. As far back as my psych degree in the late 2000s there were clear estimates of the degree of heritability of various psychological disorders - especially disorders with strong organic elements like schizophrenia and ADD/ADHD. What makes psychological disorders difficult to understand is not a mysterious hidden biogenic causation. We know at least in terms of percentage contributions, quite a bit about the involvement of physical processes and systems in psychological disorder, from the gut microbiome to inflammation. If psychological disorders were essentially diseases, with prognosis, a set of distinct aetiologies etc, psychology would just be a branch of medicine with poor data. Unfortunately mental illnesses are profoundly unlike physical illnesses in numerous ways. For example their symptomatology is usually culturally determined - e.g.: things we associate with depression in the West (dysphoria, anhedonia, melancholy etc) are quite different from the symptoms of epidemiologically similar disorders in other cultures (e.g.: pre-westernisation China). There's a lot to unpack here, but psychological disorders are profoundly more complex (ontologically) than physical disorders. Often the medical lens isn't particularly helpful. For example we see rates of disorders like anxiety and depression rise under stressful socioeconomic conditions. These are often disorders of meaning and the persons understanding of the world. There are also a host of 'culture bound' syndromes - from anorexia to folie a deux to koro, that make no sense to think of in terms of 'illness'. So it's as likely that the medical model is holding back understanding of these often sociological, psychological and cultural phenomena as helping. That said it's not nearly as simple as that, since there are genetic components to so many disorders!

ThrowawayTestr 4y ago
>For example their symptomatology is usually culturally determined Could you expand on that? How is depression different in China?
- dbspin 4y ago
  So I have no idea what the current state of the research on this is, or how depression manifests in contemporary (culturally Westernised) China, but historically there was quite a bit of research indicating it was more somaticised. People suffering from a depression like disorder were more likely to feel physically exhausted and weak than sad or hopeless. Something more like what we'd today refer to as chronic fatigue in the West. This study (from the 80s) looks like one of the origins of that idea - https://link.springer.com/article/10.1007/BF00051427 https://link.springer.com/article/10.1007/BF00051427 Bear in mind my degree is quite old at this point, but a reference point for me during my undergrad was Malcolm MacLachlan's brilliant book Culture and Health A Critical Perspective Towards Global Health. https://brownsbfs.co.uk/Product/MacLachlan-M/Culture-and-health---a-critical-perspective-towards-global-health/9780470847374 https://brownsbfs.co.uk/Product/MacLachlan-M/Culture-and-hea... Here's a quote from the book (which I was lucky enough to receive as a PDF preprint in college) "The experience of depression within an individual can vary over time – commonly referred to as the disease course – and, as already noted, it can vary between individuals of the same culture – commonly referred to as a disease syndrome. Kleinman’s suggestion that depression can also vary across cultures and across different historical epochs is quite consistent with a biologi- cal view of depression. He has also studied a condition known as neurasthenia. This condition, commonly reported in China, is characterised by a lack of energy and physical complaints such as a sore stomach. Klein- man has suggested that, although depression and neurasthenia are different illness experiences, they are both products of the same underlying disease processes – depression. In other words, neurasthenia is the Chinese version of western depression." It's obscenely expensive, but you may hypothetically be able to find other ways of reading the book online.
  - ThrowawayTestr 4y ago
    Thank you for the detailed response!
  - bloak 4y ago
    Ethan Watters looks at how mental illness is to some extent determined by culture in "Crazy like us", though he looks at Japan rather than China. Do you know that book?
edgyquant 4y ago
>there were clear estimates of the degree of heritability of various psychological disorders - especially disorders with strong organic elements like schizophrenia How can this be stated with any certainty when we don’t even have a medical definition of what schizophrenia actually is, just a description of some symptoms. What are these genetic components, and how can we be at all sure it isn’t a behavioral transmission?
- dbspin 4y ago
  "just a description of some symptoms." Yes - all psychological disorders are syndromal. None are purely genetic or environmental, in fact the DSM and and ICD explicitly rule out psychosis or positive schizophrenic like symptoms caused by say toxin poisoning from their diagnostic criteria. What we can do is heritability studies on those who do fit the diagnostic criteria. We can test their relatives on neurocognitive batteries, including twin studies and get quite an accurate picture of the level to which genes contribute on a population level. Here's one review - https://academic.oup.com/schizophreniabulletin/article/43/4/788/2549005 https://academic.oup.com/schizophreniabulletin/article/43/4/... So you're right in asserting that schizophrenia likely isn't one clearly delineated disorder, but this is less due to an unclear 'medical definition', and more due to the fact that it's not entirely endophenotypic. It has sociogenic and psychogenic elements too - as do ALL psychological disorders. We diagnose from symptoms, but symptoms too are culturally mediated. We can never have a simple 'medical definition' of schizophrenia, because it's not only genetic, or only environmental, or only behavioural. It exists on the line between the creation and performance of personhood, and the biological mechanisms that make that possible. Put another way - if schizophrenics behaved 'normally' we wouldn't have a disorder at all. We deduce an internal experience of suffering, based on what they tell us of their inner experience (delusions and hallucinations), and the ways in which their behaviour departs from normative. We see a disease course, because many patients also have physical symptoms over the life course (like catatonia), although this is complicated by the brain damage caused by long term use of antipsychotics. A disorder of perception, selfhood and behaviour isn't reducible to a biological mechanism gone wrong - any more than joining a cult, following an extremist belief, or committing an act of terrorism would be. Those behaviours too could be said to have a genetic component - in so far as there are measurable aspects of impulsivity, neuroticism etc that can be used to explain them. But they're clearly not a disease in the conventional sense of the word.

by dbspin 4y ago

ThrowawayTestr 4y ago

>For example their symptomatology is usually culturally determined Could you expand on that? How is depression different in China?

dbspin 4y ago
So I have no idea what the current state of the research on this is, or how depression manifests in contemporary (culturally Westernised) China, but historically there was quite a bit of research indicating it was more somaticised. People suffering from a depression like disorder were more likely to feel physically exhausted and weak than sad or hopeless. Something more like what we'd today refer to as chronic fatigue in the West. This study (from the 80s) looks like one of the origins of that idea - https://link.springer.com/article/10.1007/BF00051427 https://link.springer.com/article/10.1007/BF00051427 Bear in mind my degree is quite old at this point, but a reference point for me during my undergrad was Malcolm MacLachlan's brilliant book Culture and Health A Critical Perspective Towards Global Health. https://brownsbfs.co.uk/Product/MacLachlan-M/Culture-and-health---a-critical-perspective-towards-global-health/9780470847374 https://brownsbfs.co.uk/Product/MacLachlan-M/Culture-and-hea... Here's a quote from the book (which I was lucky enough to receive as a PDF preprint in college) "The experience of depression within an individual can vary over time – commonly referred to as the disease course – and, as already noted, it can vary between individuals of the same culture – commonly referred to as a disease syndrome. Kleinman’s suggestion that depression can also vary across cultures and across different historical epochs is quite consistent with a biologi- cal view of depression. He has also studied a condition known as neurasthenia. This condition, commonly reported in China, is characterised by a lack of energy and physical complaints such as a sore stomach. Klein- man has suggested that, although depression and neurasthenia are different illness experiences, they are both products of the same underlying disease processes – depression. In other words, neurasthenia is the Chinese version of western depression." It's obscenely expensive, but you may hypothetically be able to find other ways of reading the book online.
- ThrowawayTestr 4y ago
  Thank you for the detailed response!
- bloak 4y ago
  Ethan Watters looks at how mental illness is to some extent determined by culture in "Crazy like us", though he looks at Japan rather than China. Do you know that book?

edgyquant 4y ago

>there were clear estimates of the degree of heritability of various psychological disorders - especially disorders with strong organic elements like schizophrenia How can this be stated with any certainty when we don’t even have a medical definition of what schizophrenia actually is, just a description of some symptoms. What are these genetic components, and how can we be at all sure it isn’t a behavioral transmission?

dbspin 4y ago
"just a description of some symptoms." Yes - all psychological disorders are syndromal. None are purely genetic or environmental, in fact the DSM and and ICD explicitly rule out psychosis or positive schizophrenic like symptoms caused by say toxin poisoning from their diagnostic criteria. What we can do is heritability studies on those who do fit the diagnostic criteria. We can test their relatives on neurocognitive batteries, including twin studies and get quite an accurate picture of the level to which genes contribute on a population level. Here's one review - https://academic.oup.com/schizophreniabulletin/article/43/4/788/2549005 https://academic.oup.com/schizophreniabulletin/article/43/4/... So you're right in asserting that schizophrenia likely isn't one clearly delineated disorder, but this is less due to an unclear 'medical definition', and more due to the fact that it's not entirely endophenotypic. It has sociogenic and psychogenic elements too - as do ALL psychological disorders. We diagnose from symptoms, but symptoms too are culturally mediated. We can never have a simple 'medical definition' of schizophrenia, because it's not only genetic, or only environmental, or only behavioural. It exists on the line between the creation and performance of personhood, and the biological mechanisms that make that possible. Put another way - if schizophrenics behaved 'normally' we wouldn't have a disorder at all. We deduce an internal experience of suffering, based on what they tell us of their inner experience (delusions and hallucinations), and the ways in which their behaviour departs from normative. We see a disease course, because many patients also have physical symptoms over the life course (like catatonia), although this is complicated by the brain damage caused by long term use of antipsychotics. A disorder of perception, selfhood and behaviour isn't reducible to a biological mechanism gone wrong - any more than joining a cult, following an extremist belief, or committing an act of terrorism would be. Those behaviours too could be said to have a genetic component - in so far as there are measurable aspects of impulsivity, neuroticism etc that can be used to explain them. But they're clearly not a disease in the conventional sense of the word.