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ADHD in particular is located to very specific areas in the brain. Primarily the dorsolateral prefrontal cortex and areas in the cingulate cortex. We can see ne

ADHD in particular is located to very specific areas in the brain. Primarily the dorsolateral prefrontal cortex and areas in the cingulate cortex. We can see neuroanatomy differences on scans, which, while not specific or sensitive enough for diagnosis, are definitely real physical changes in the brain, and they're pretty consistent across diagnosed vs baseline. There are lots of psychiatric disorders where that doesn't take place, but developmental neuropsychiatric disorders don't fall under that "are they even alike at all" kind of umbrella. In some kind of awful alternate universe we could pretty reliably induce them with gamma knife surgery, for example. Depression is much easier to argue that it's a less specific symptom of a larger constellation, with lots of causes and lots of manifestations.

andoando 2y ago
Can you point me to a study showing these brain scans being different from those with diagnosed ADHD and not? The evidence would furthermore have to show that this difference is apparent not just from adhd vs non adhd but adhd vs anxiety, depression etc. And lastly, are these changes perhaps an affect of taking stimulants? And how significant are these results? Are we talking about a few percent difference? Are 10% of diagnoses ADHD shown to have statistically significant differences, 20, 50, 90? Depending on the figure, my criticism of the diagnostic criteria remains. Because if it is a low figure like 10%, that means 90% of the diagnoses aren't supported by any scientific evidence. From what I've been told, including professionals this evidence does not exist. I've also seen studies which indicate that psychiatric evaluations are entirely inconsistent across physicians.
- jaggederest 2y ago
  > The morphometric findings predicted an ADHD diagnosis correctly up to 83% of all cases. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391018/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391018/ It's not good enough for diagnosis - you want to hit 95+% accuracy for diagnostic. And MRIs are extremely expensive compared to 2-3 outpatient psychology appointments. But it's real.
  - andoando 2y ago
    I admit the study looks pretty good, but Id still have to see if these changes are present in those with depression/anxiety, etc and 2. are not result of stimulant use to be convinced. I found this if youre interested which cites more studies https://ajp.psychiatryonline.org/doi/full/10.1176/appi.ajp.2011.11020281 https://ajp.psychiatryonline.org/doi/full/10.1176/appi.ajp.2... >It's not good enough for diagnosis - you want to hit 95+% accuracy for diagnostic. This doesn't quite make sense to me, because you're comparing it to the current diagnostic criteria and assuming it to be 100% accurate. If we want to be totally scientific, we ought to just do these scans and diagnose people with low gray matter volume, etc and drop the DSM, ADHD etc.
    - pixl97 2y ago
      And if we start scanning tons of brains and finding out that X% of people with low gray matter volume do not exhibit any ADHD symptoms?
      - arcticbull 2y ago
        Bayes strikes again.
  - Aurornis 2y ago
    > https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391018/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391018/ Two major problems with studies like this: 1. The number of brain sub-regions and associated variables they're looking at is huge. Perhaps more than the number of patients in the study, depending on how you look at the data. If you collect enough data points on two groups of about ~30 people each and you run enough regressions, eventually you'll find some model that works on your small data set. This would need to be tested against a much larger cohort. 2. They did not control for stimulant usage at all. In fact, they note that stimulant use was vastly higher in the ADHD group, because obviously you need an ADHD diagnosis to receive ongoing stimulant prescriptions. It's a delicate topic, but we know that stimulant use in some cases is associated with changes in brain structure and blood flow. It's a huge variable that is hard to control for in a study like this. Overall, I don't find a study with 31 ADHD patients that tested dozens and dozens of different variables to be all that conclusive. Perhaps useful for focusing future research, but a singular study like this isn't very conclusive.
deleted 2y ago
[deleted]
Aurornis 2y ago
Unfortunately, the topic of ADHD and brain imaging has been full of bad research and grifters. At the extreme end, people like Dr. Amen were writing books about how ADHD and neuroimaging were correlated, which turned into attempts to sell SPECT imaging for ADHD purposes through his clinics. Using brain imaging to push questionable psychiatry premises was very popular for a while, and you need to take a lot of research from that era with a huge grain of salt. Remember that with the right settings, neuroscientists can even produce images showing activity in brain regions of completely dead salmon: https://www.wired.com/2009/09/fmrisalmon/ https://www.wired.com/2009/09/fmrisalmon/
- samhw 2y ago
  Quite. Psychiatry loves to talk about brain scans and neuroanatomy, but until it dares to actually use them for diagnosis, I think it should be regarded as window dressing. And you should always read these studies with a careful eye to whether the ADHD subjects are medicated. Often the studies literally measure the effect of the medication and nothing else. (It's a cruel irony for schizophrenics, who are put on antipsychotics that shrivel the cerebral cortex, only to find their shrivelled cerebral cortex brandished as evidence of their supposed dysfunction.) Also, note that fMRI does not and cannot indicate structural abnormalities in the brain. It just measures current brain activity, as revealed by the flow of magnetically-charged oxygenated blood through the brain. It tells us these people's brains are currently behaving differently from control subjects' brains. Which, it seems to me, is stating the bleeding obvious.
  - Jach 2y ago
    It's a shame that every time someone (e.g. upthread) mentions how even just MRIs are very expensive, often as an excuse for not using such tools, I think of all the times I've heard that other places like India make them quite cheap. Well, it's just one part of a giant pile of problems. Thanks for the reminder about schizophrenics. Even though I've known about the effect (and especially the effect with use of lithium, which is thankfully not so commonly used), I've sort of forgotten about it as a factor in my thinking about the recent struggles of someone in my personal life. It's probably not forgotten by those working in the system, and wouldn't surprise me if it contributes to the incentives of the system encouraging people to be shut-ins and never challenge anything.

andoando 2y ago

Can you point me to a study showing these brain scans being different from those with diagnosed ADHD and not? The evidence would furthermore have to show that this difference is apparent not just from adhd vs non adhd but adhd vs anxiety, depression etc. And lastly, are these changes perhaps an affect of taking stimulants? And how significant are these results? Are we talking about a few percent difference? Are 10% of diagnoses ADHD shown to have statistically significant differences, 20, 50, 90? Depending on the figure, my criticism of the diagnostic criteria remains. Because if it is a low figure like 10%, that means 90% of the diagnoses aren't supported by any scientific evidence. From what I've been told, including professionals this evidence does not exist. I've also seen studies which indicate that psychiatric evaluations are entirely inconsistent across physicians.

jaggederest 2y ago
> The morphometric findings predicted an ADHD diagnosis correctly up to 83% of all cases. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391018/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391018/ It's not good enough for diagnosis - you want to hit 95+% accuracy for diagnostic. And MRIs are extremely expensive compared to 2-3 outpatient psychology appointments. But it's real.
- andoando 2y ago
  I admit the study looks pretty good, but Id still have to see if these changes are present in those with depression/anxiety, etc and 2. are not result of stimulant use to be convinced. I found this if youre interested which cites more studies https://ajp.psychiatryonline.org/doi/full/10.1176/appi.ajp.2011.11020281 https://ajp.psychiatryonline.org/doi/full/10.1176/appi.ajp.2... >It's not good enough for diagnosis - you want to hit 95+% accuracy for diagnostic. This doesn't quite make sense to me, because you're comparing it to the current diagnostic criteria and assuming it to be 100% accurate. If we want to be totally scientific, we ought to just do these scans and diagnose people with low gray matter volume, etc and drop the DSM, ADHD etc.
  - pixl97 2y ago
    And if we start scanning tons of brains and finding out that X% of people with low gray matter volume do not exhibit any ADHD symptoms?
    - arcticbull 2y ago
      Bayes strikes again.
- Aurornis 2y ago
  > https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391018/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5391018/ Two major problems with studies like this: 1. The number of brain sub-regions and associated variables they're looking at is huge. Perhaps more than the number of patients in the study, depending on how you look at the data. If you collect enough data points on two groups of about ~30 people each and you run enough regressions, eventually you'll find some model that works on your small data set. This would need to be tested against a much larger cohort. 2. They did not control for stimulant usage at all. In fact, they note that stimulant use was vastly higher in the ADHD group, because obviously you need an ADHD diagnosis to receive ongoing stimulant prescriptions. It's a delicate topic, but we know that stimulant use in some cases is associated with changes in brain structure and blood flow. It's a huge variable that is hard to control for in a study like this. Overall, I don't find a study with 31 ADHD patients that tested dozens and dozens of different variables to be all that conclusive. Perhaps useful for focusing future research, but a singular study like this isn't very conclusive.

deleted 2y ago

[deleted]

Aurornis 2y ago

Unfortunately, the topic of ADHD and brain imaging has been full of bad research and grifters. At the extreme end, people like Dr. Amen were writing books about how ADHD and neuroimaging were correlated, which turned into attempts to sell SPECT imaging for ADHD purposes through his clinics. Using brain imaging to push questionable psychiatry premises was very popular for a while, and you need to take a lot of research from that era with a huge grain of salt. Remember that with the right settings, neuroscientists can even produce images showing activity in brain regions of completely dead salmon: https://www.wired.com/2009/09/fmrisalmon/ https://www.wired.com/2009/09/fmrisalmon/

samhw 2y ago
Quite. Psychiatry loves to talk about brain scans and neuroanatomy, but until it dares to actually use them for diagnosis, I think it should be regarded as window dressing. And you should always read these studies with a careful eye to whether the ADHD subjects are medicated. Often the studies literally measure the effect of the medication and nothing else. (It's a cruel irony for schizophrenics, who are put on antipsychotics that shrivel the cerebral cortex, only to find their shrivelled cerebral cortex brandished as evidence of their supposed dysfunction.) Also, note that fMRI does not and cannot indicate structural abnormalities in the brain. It just measures current brain activity, as revealed by the flow of magnetically-charged oxygenated blood through the brain. It tells us these people's brains are currently behaving differently from control subjects' brains. Which, it seems to me, is stating the bleeding obvious.
- Jach 2y ago
  It's a shame that every time someone (e.g. upthread) mentions how even just MRIs are very expensive, often as an excuse for not using such tools, I think of all the times I've heard that other places like India make them quite cheap. Well, it's just one part of a giant pile of problems. Thanks for the reminder about schizophrenics. Even though I've known about the effect (and especially the effect with use of lithium, which is thankfully not so commonly used), I've sort of forgotten about it as a factor in my thinking about the recent struggles of someone in my personal life. It's probably not forgotten by those working in the system, and wouldn't surprise me if it contributes to the incentives of the system encouraging people to be shut-ins and never challenge anything.