Exciting news from the field of brain scanning technology is poised to make big waves across multiple scientific disciplines.  Researchers have devised a portable PET scanner!  That might not seem as exciting to you as it does to me, but if you’ll indulge for a moment, you could catch up with me.

In the world of brains, or at least, in the world of studying brains, things get complicated pretty quick.  After all, it is brain surgery.  In ages past we were at the mercy of doctors who thought drilling holes in our skulls was an effective way to treat psychological and neurological conditions (actually, neither of those things, they called them brain maladies, and practically nothing was known about what they were or what caused them).  Great strides have been made in the realm of detecting, diagnosing, and treating the various ways our brains malfunction – the most complicated biological organ we know of.  We’ve dissected, analysed, poked, prodded, shocked, sliced, hacked, and generally made a mess of all kinds of brains, all in an effort to understand how they work, and how they don’t work.

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This is a typical PET scanner

Modern science has pushed the front line of that effort further than anyone in the age of lobotomies could have imagined.  We have technology that allows us to take pictures of our brains, while they’re still in our heads.  And no power-drills are needed!  There’s CAT (computerized axial tomography), MRI and fMRI (magnetic resonance imaging), MEG (magnetoencephalography), EEG (electroencephalography), NIR and fNIR (near-infrared spectroscopy), SPECT (Single-photon emission computed tomography), EROS (event related optical signal), DOI (diffuse optical imaging) and of course PET or positron emission tomography.

Each of those intimidating scientific terms, which are collectively known as neuroimaging techniques, represents a different way to use technology to physically see the inside of your body, without opening you up.  There are two distinct categories of neuroimaging technology: structural and functional.

Structural refers to techniques that simply take a static picture, while functional (which is designated by the letter f in the acronyms) refers to techniques that offer a dynamic view of neurological processes, whether in real-time or by recording.  It’s like the difference between a still camera and a video camera.

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A whole-body PET scan animation

One thing all of those techniques has in common (with the exception of EEG and NIR) is that the person (or animal) being scanned must remain completely still during the process.  That limitation is due to both the way the image is produced and to the resolution needed to make the technique useful.  Obviously, when we’re talking about the nervous system, the elements that doctors need to look at are microscopic.  In a sense, you can think of each of those technologies as really complicated (and expensive) microscopes that can look right through your skin and bones.  So that means scanner fidelity is extremely important.  And you thought motion blur on your camera phone was a problem.

That all of these neuroimaging techniques requires the patient to keep still has been a problem since their first inception.  Not only does it make the process more difficult, and the diagnoses that much more uncertain, but it severely limits the scope of research into how our brains work and what happens to them under different environmental conditions.  In fact, this limitation has held back advancements in psychology and neuroscience for decades.

As mentioned, EEG and NIR imaging techniques aren’t thus restricted, but there’s a major trade-off in reduced fidelity.  And as we’ve already noted, fidelity is important.

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Julie Brefczynski-Lewis, a research assistant professor at the WVU Center for Neuroscience, demonstrates the portable PET brain scanner prototype

Enter ambulatory microdose positron emission tomography, or AMPET.  I know, more scary scientific words.  OK, here’s your crash course in positron emission tomography.

When you have a PET scan, the doctors inject you with a radioactive serum.  That serum contains isotopes (like little tags) that circulate through your blood stream.  The scanner can detect those tags and provide a map of where those tags are inside your body at any given time.  This is useful because when you exert yourself your blood rushes to whatever structure or body part you’re using.  If that blood contains those radioactive isotopes, it also shows the scanner exactly where those structures are.  More than that though, at a high enough resolution, it provides doctors with an extremely detailed look at the physical structure and function of whatever they’re looking at.  Very useful for diagnosing a malfunction in brain centers that are otherwise difficult to image.

So, traditional PET scans, like other scan techniques, require the patient to lay perfectly still inside a giant machine, while it clunks and clamors, sometimes for extended period of time.  It makes the whole thing even more difficult, for everyone involved.

Now though, researchers at The West Virginia University Centers for Neuroscience, working under a $1.5m grant from the National Institutes of Health’s Brain Initiative, have built a version of the PET scanner using new silicon photomultipliers, that is not only much smaller than the traditional technology, but which fits on the patient’s head like a helmet, and provides a scan resolution 400% greater than EEG or NIR, even when the patient is moving around.

 

In case the point here hasn’t sunk in; this means that doctors can image people’s brains while they’re performing different tasks, providing incredibly detailed pictures of what happens inside different brain structures while they do it!  The increased resolution also extends the reach of PET to brain structures located deep inside the brain, like the hippocampus.

This is huge news!  It opens a great many doors to medical diagnoses in the realms of Alzheimer’s disease, Parkinson’s, stroke, autism, and virtually every form of mental illness.  It also present new opportunities to study behaviour and how social and environmental conditions affect the brain, and in turn, how they affect our psychology.

Indeed, AMPET is poised to knock down the dam that has long held back the flow of research into near-death and out-of-body experiences, biotechnology integration (like neural implants for prosthetics etc), memory manipulation, Artificial Intelligence, and even virtual reality.  It can’t really be overstated, this is a major step toward the future we’ve seen on the big screen so many times.

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