THE MIND’S PUPPET MASTER
You’d think ‘why do we have a brain’ is the kind of question philosophers would ask themselves. Scientists, after all, are invariably more interested in the ‘how’ of things.
Not Daniel Wolpert.
As a neuroscientist, brains are his thing. And the question of why we have a brain has occupied much of his academic and research life.
And after 25 years spent learning about and researching brains, he’s arrived at a conclusion so disruptive, it turns everything we know and believe about ourselves on its head.
Which is that the real reason we have brains is not to think or feel, but to help us control movement. Everything, in fact, that the brain does – or doesn’t do – is linked to helping the body perform complex and adaptable movements. “Movement is the only way we have of interacting with the world, whether foraging for food or attracting a waiter’s attention. Indeed, all communication, including speech, sign language, gestures and writing, is mediated via the motor system. Taking this viewpoint, the purpose of the human brain is to use sensory signals to determine future actions,” he says.
In his lab at the Department of Engineering at Cambridge University, where he heads the Sensorimotor Learning Group, he’s using robotics, virtual reality techniques and computational skills to understand how the brain controls the body’s movements.
“I am a movement chauvinist,” he said at a TED Global talk at Edinburgh last year. “I believe movement is the most important function of the brain and don’t ever let anyone tell you anything different.”
He’s a scientist through and through, although for a time it looked like he wasn’t sure in what direction to head. He started out studying maths at Cambridge, but quit after the first year to do medicine “because the medics were having much more fun than the mathematicians,” he laughed in an interview to the University College London’s (UCL) online magazine. While there, he got caught up in the excitement over networks and brain modeling and enrolled for a PhD in Physiology. A love of math resurfaced when he went to MIT for postdoctoral studies in Cognitive Sciences, and he started to focus deeply on the computational side of things. He returned to UCL and worked for the subject for 10 years, until a call out of the blue from Cambridge. “They asked if I was interested in a chair in Engineering and I told them they’d got the wrong guy,” he laughs. “Turns out they wanted to create a bioengineering group and wanted to hire a biologist with an interest in engineering.”
Today, at his lab, he leads a team of researchers who develop theories and conduct experiments to understand how the brain controls movement; something, it turns out, that’s way harder than we imagine. The brain has to work with staggeringly complex hardware – hundreds of joints and almost 400 muscles, most of which can move in a range of ways, at different angles. Then there are thousands of motor units per muscle, as well as a nearly infinite variety of possible muscle contractions – it all adds up to make a task like tying your shoelace a feat of engineering that the brain directs by relying on a gamut of information. And those choices have almost infinite computations. It’s why, explains Wolpert, a computer can beat a human being at a chess game with relative ease (finite options), but even a 5-year old can move the physical pieces on a chessboard with significant more dexterity than a robot.
What about love, then, and feelings, and emotions and all else the brain does. Are they all incidental? Wolpert argues they’re all in some way aids to movement – and ultimately, to reproduction, which is the evolutionary goal. “We study sensation or memory without figuring out why they’re important,” he says. “But the fact is that we forget most of our childhoods and it’s fine – because those memories don’t affect our movements later in life. The brain only needs to store things that are really going to affect movement.”
It’s a game-changing concept, and one that makes emotional and spiritual thinkers uncomfortable. To Daniel, that would probably mean his job as a scientist is well done!
