Psychiatrist, Dr. Daniel Carlat has a great article in Wired about the overhype of brain scans. Referring to the terabytes of brain scan data we've accumulated since the advent of the EEG, he asks: "Are we really seeing the mind in action, or are we allowing ourselves to be seduced by images that may actually tell us very little?"
The over-extrapolated brain scan is being utilized in many different arenas outside of medicine now - marketing, law, and politics to name a few.
In the article, Dr. Carlat recounts his experience receiving a brain evaluation at the Amen Clinic - which touts a "prescription for a better brain." Dr. Amen does a Spect (a specific kind of brain scan) on Dr. Carlat and takes a personal and family history of depression.
An excerpt of his "analysis":
...Scrutinizing the scans some more, he (Dr. Amen) says, "You need to be busy to be happy. Your brain is cool at rest. You need stuff in your life to feel alive, together, and connected." He looks at another view, this one showing only the most active regions of my brain. "In this scan, you have increased activity in your thalamus, your two basal ganglia, and your cingulate cortex." He picks up a pen and draws a line connecting these four regions to the right lateral temporal lobe. "I call this the diamond plus.' It's a pattern of angst, and we see it in people who have had significant trauma in their lives."Dr. Carlat goes on to make the apt comparison of these results to a palm reading:
...I find myself comparing my assessment meeting with Amen to experiences I've had with shrewd palm readers. Like them, Amen made vague pronouncements that could apply to anyone: "You're happier when you're busy." When he made specific statements about my moods and life events, they seemed to be based on information he obtained the old-fashioned way — by asking questions. He already knew about my family history of depression and my mother's suicide when he mentioned a "predisposition to depression" and "significant trauma." Occasionally, he was completely off the mark, like when he saw neural signs of temper problems. In fact, when my wife and I argue, my calmness is exasperating, leading her to ask, "Do you even have a pulse?"Dr. Carlat discusses the Amen Clinic with a vocal skeptic (Robert Rubin) who easily describes why this is such shotty science:
Rubin, a noted researcher on brain functioning in depression, draws two circles on a sheet of paper. He points to the first and says, "Let's say this represents a bunch of people with low activity of the frontal lobe, and let's say, for the sake of argument, that many of them also have depression." Then he points to the second circle. "And here are all the people without depression. Do any of these people also have low frontal lobe activity? You bet they do. So there are people with depression who have this finding, and people without depression with this finding. How is the finding helpful?"When I studied neuroscience in college, I was always weary of extrapolating results from neuroimaging studies. And I still think neuroscience is going down a fruitless path in this direction. This idea that we can identify our inclinations, temperament, and moods, or diagnose our depression via fMRI's, EEGs, and Spect is pervasive, but completely unproven. I don't quite agree with Dr. Carlat's idea that while we haven't accomplished this mental transparency yet, we will eventually. I don't see this ever happening, here's why.
This logic is like running a scan on the intel chip in your Macbook to diagnose why a song won't play on iTunes. Or vice versa, to run a scan on your mother board and determine that you're probably having trouble running macros in Excel. The language of the software is completely different than the language of the hardware. And while you need the hardware to run the software, tweaking the hardware isn't going to fix specific software problems.
This metaphor applies to the distinction between our brain and consciousness - they speak different languages. You can't diagnose a problem in consciousness by analyzing the biology of the brain - it's a waste of time. Depression is not a disease of the brain, like some kidney disease that can be treated with medication. The brain creates a whole bigger than the sum of its parts - consciousness. But that doesn't mean that tweaking its wires can fix something specific in consciousness. This only works in extreme cases like giving L-Dopa to Parkinson's patients (in Awakenings).
The only way to determine a cause for depression is to see the story of an individual's life experience, and analyze what's problematic (no small task from what I've heard). This analysis must be on par with that life experience, which is on the software level (mind/consciousness); not the hardware level (brain). No one speaks the language of snyapsese.
This is why I find it so important to differentiate between neurological and psychological disorders - a brain scan is vital for finding a stroke, brain tumors, or early signs of Alzheimer's Disease, but I highly doubt we'll ever be able to use one to see the actual content of our consciousness. This kind of transparency is a lost cause.
A good pop culture example of this logical shortcoming is the major plot hole in Minority Report - how exactly are computers translating the brain activity of the pre-cogs into visual images displayed on monitors? No brain scan in the world will solve the phenomenological problem. Guess that's why it's called science fiction...
UPDATE: Dr. Carlat posted some more thoughts on the response to his Wired article. The more I read about Amen, the more of a charlatan he appears to be...