Thoughtful Evidence

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As any marketing professional will tell you, knowing how to properly brand an idea is essential for its success.  And while scientists often don’t like to admit it, they are hardly immune to the power of branding.

PhrenologyPixThe field of phrenology is a good case in point. A deliberate verbal construction of two ancient Greek conceptual heavyweights related to the ordered structured of our thoughts – phren (mind) and logos (reason) – its very name seemed to strongly validate its existence.  

After all, how could a field dedicated to amassing a structured knowledge of the mind possibly be scientifically flawed?

Well, it turns out that it can.  Phrenology had its day, of course.  And to be fair, when developed by Franz Joseph Gall in the late 18th century, it represented a significant advance in our understanding, emphasizing as it did the importance of explaining mental states through the neurophysiology of our brains rather than merely through the previous window of religious or philosophical abstraction.

But by the time people started engaging in detailed measurements of skull sizes to determine which one of the 27 so-called “brain organs” was most responsible for someone’s personality, it was clear that the field had descended to the depths of pseudo-science from which it never recovered.

Yet aspects of its legacy persist. According to Duke University’s renowned neuroscientist Miguel Nicolelis, Gall’s general framework of dividing the brain into distinct, localized areas that control separate aspects of human behavior, “morphed into one of the key dogmas of twentieth-century neuroscience”.  A dogma, as it happens, that he is firmly convinced is nothing less than flat-out wrong.

neuron cluster

What Dr. Nicolelis can’t accept is the pre-eminence that classical theories of the brain give to a sense of locality: that the brain is partitioned into distinct regions of neurons responsible for different types of information processing. For him, the fundamental thinking unit isn’t a neuron at all, but rather populations – clusters – of neurons that are themselves distributed throughout many different areas of the brain.  And when the brain acts, it does so by integrating all these distributed clusters of neurons.

“It is like the population of neurons is voting at each moment in time, and the real outcome depends on this voting. It doesn’t depend on a specific class of cells or a cluster of neurons. It depends on this distributed representation.”

Well, people have argued about how the brain works for centuries. What separates Dr. Nicolelis from his many predecessors is that he has managed to construct a good many convincing experiments that back up his hypothesis of the distributed processing systems of the brain.

For over twenty years, Nicolelis has distributed detectors throughout the brains of rats, monkeys and humans to directly measure their electrical signals. This, in itself, is astounding enough. But what seems straight out of the realm of science fiction is that he also managed to direct these signals and to machines that the animals could actually control just by thinking.

In perhaps his most remarkable experiment, he trained a Rhesus monkey to walk upright on a treadmill while measuring its brain waves.  These signals are then sent to a processor that controlled a 100 kg automated robot, while the real-time image of the robot is beamed back to a video screen directly in front of the monkey.

The monkey, just like many of us in our health clubs, gets used to walking a treadmill and watching a large video screen. Except weight loss here is not the issue, the goal is simply to keep the robot walking: as long as the video screen shows the robot walking, the monkey gets a squirt of his favourite fruit juice.

The treadmill is turned on. The monkey walks, the robot walks, the monkey gets his fruit juice and all is well.   But then the treadmill is turned off and the monkey, strapped to a device, is naturally forced to stop walking as well.   But then something remarkable happens: the robot keeps walking.

Because, since the robot is driven by the monkey’s brain waves, all the monkey has to do is think about walking to make the robot move. And the monkey realizes that as long as the robot moves, he keeps getting his fruit juice. So he keeps thinking about walking, the robot keeps walking, and the fruit juice keeps coming well after the treadmill has been turned off and the monkey has long stopped walking.

Oh yes, I forgot one little thing: Nicolelis and his colleagues in North Carolina decided to put the robot the monkey was controlling in Japan.  Which seems almost like showing off. 

“We got a 5 kilogram monkey to control a 100 kilogram, 150 centimetre robot in Kyoto by physically generating movement out of brain waves”.

All very impressive, you might think. But so what? Controlling robots by brain waves is not generally an issue that most humans are preoccupied with, let alone monkeys. But that, of course, is profoundly missing the point.

“I think that in the short run, over the next few years, the main impact of this thing we call ‘brain-machine interface’, this paradigm that we have been talking about, will be in medical rehabilitation. No doubt about it.

“Patients who are paralyzed will benefit from this possibility of bypassing the lesion and using brain activity to control prosthetic devices of a huge variety: single limb, lower limb, whole body, upper limb. There is now a huge diversity of potential devices. Then there’s communication. For people who cannot communicate, they will be able to use their brain activity to communicate. It’s not only paralysis.

“We are working here in the lab on prosthetic devices for Parkinson’s disease that take advantage of the basic science that we’ve discussed regarding this new model of the brain. They would never work if the brain operated on the classic model.”

“Brain-machine interface”, or BMI, is, in fact, a bit of a clunky sounding name; and it’s likely the case that an astute marketing professional could come up with something a lot catchier to help generate even greater societal interest in these fascinating ideas.  But there’s nothing quite like some rigorous experimental tests to give us confidence that those ideas are actually true.

Howard Burton,

To best explore the topics raised in this post for teaching and learning, please see below a number of related expert resources that are part of Ideas Roadshow’s IBDP Portal which offers a dynamic IB-specific database of 500+ authoritative video and print resources featuring more than 80 world-leading researchers, including two Nobel Laureates, explicitly created to meet the needs of both teachers and students in the Diploma Programme – please visit our new website  for further information.

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