Why Diagnosing Mental Illness Via Brain Scan Matters and Why It Doesn’t

Recently, it was announced that the very first diagnostic brain scan for a mental illness became Food and Drug Administration-approved. This test uses electroencephalography (EEG) to diagnose attention-deficit/hyperactivity disorder (ADHD). Finally, people with a mental illness (in this case ADHD) can point to a biological test and say, look – see – my disorder is biological in nature and we can test for it.

It’s not terribly surprising that ADHD is the first disorder to have this type of test as we understand an ADHD brain better than we understand a brain with other disorders. Nevertheless, it won’t be the last. Scientists are actively working on diagnostic tests for depression, autism, bipolar and schizophrenia too.

And while I consider this a major breakthrough in our real, tangible understanding of mental illness, there are reasons why diagnosis by brain scans matters and reasons why it doesn’t.

Why Do Mental Illness Brain Scans Matter?

As a person who fights antipsychiatry lobbies on a regular basis, it’s a real boon to be able to say that there’s an FDA-approved biological test for a mental illness. While I could always say that there was evidence of mental illness in the brain, I could never point to one, scientifically proven and accepted test – and now I can. Now I’m sure the antipsychiatry lobby will come up with denials of the science, and that’s fine, but being able to point to the test is still a big win.

And, of course, it’s not just antipsychiatrists who lack understanding of mental illness. No, many people do and it will increase understanding to be able to say there is a test. It will increase acceptance. It’s much harder to deny an illness that we can see and diagnose in a brain scan.

Finally, a diagnostic test allows for a greater degree of certainty in diagnosis, which, in this case, is a particularly good thing as we’re talking about diagnosis in children. It’s a major improvement to be able to differentiate childhood ADHD from bipolar disorder or another disorder when we know that sometimes these disorders can look somewhat the same in children.

Why Mental Illness Brain Scans Don’t Matter

On the other hand, brain scans really don’t matter at all. As I stated above, it will force a greater understanding of mental illness and that is a benefit, but that’s not a benefit to patients directly. That’s a prying open of close-minded, misinformed individuals. Really, that benefits them more than patients.

Secondly, the above test is to be used in conjunction with other medical and psychiatric assessment tools. In other words, the brain scan is supplementary – it’s not designed to be used on its own. So if we’re still relying on the standard tests, how much good is a brain scan really?

Additionally, this test is going to be out of reach for many (if not most) people. Few people can afford to pop off for an expensive medical test that, at least initially, likely won’t be covered by insurance. Plus, few places are going to be able to process a brand new test.

Finally, we develop brain scans based on our understanding of those that have been diagnosed traditionally. So if we misdiagnose people then our research is flawed; and, of course, misdiagnosis is always an issue.

Brain Scans Make People Feel Better

But brain scans do make people feel better. If we can point to a scan or a blood test we feel more confident in our diagnosis. It’s the nature of the beast. We don’t want to believe that our diagnosis is based on the clinical judgement of one expert – even if that clinical judgement is as good as a biological test in highly-skilled specialists (of course, there are many not-so-highly-skilled professionals doing diagnosing too).

So if there was a brain scan for bipolar disorder would I run out and get it? Meh. If it were free I would, but if it weren’t, I probably wouldn’t. Why? Because I know my illness. I know it intimately. And know it fits the diagnostic criteria of bipolar disorder and I know what medications have worked to alleviate it. A brain scan isn’t going to tell me anything I don’t already know.

That being said, as our scans become more sophisticated, they will become more useful. Soon they will be able to point to the right treatment for a person and that will be incredibly useful, particularly early in treatment. So right now their use is beneficial, just not as much as I would like.

You can find Natasha Tracy on Facebook or GooglePlus or @Natasha_Tracy on Twitter.

Image provided by Wikipedia.