Health Can you think yourself into

international bestseller The Brain that Changes Itself by Canadian psychotherapist Norman Doidge.

“Oh my God,” she says. “For the first time it really showed me it was possible to heal my brain. Not only that it was possible, that it was up to me.”

After reading Doidge’s book, Hampton began living what she calls a “brain-healthy” life. That includes yoga, meditation, visualisation, diet and the maintenance of a positive mental attitude.

The science of neuroplasticity, she says, has taught her that: “You’re not stuck with the brain you’re born with. You may be given certain genes but what you do in your life changes your brain. And that’s the magic wand.”

Hampton’s not alone in her enthusiasm for neuroplasticity, which is what we call the brain’s ability to change itself in response to things that happen in our environment. Claims for its benefits are widespread and startling.

Half an hour on Google informs the curious browser that neuroplasticity is a “magical” scientific discovery that shows that our brains are not hard-wired like computers, as was once thought, but like Play-Doh or a “gooey butter cake”.

This means that “our thoughts can change the structure and function of our brains” and that by doing certain exercises we can actually, physically increase our brain’s “strength, size and density”.

And age is no limitation: neuroplasticity shows that “our minds are designed to improve as we get older”. It doesn’t even have to be difficult. “Simply by changing your route to work, shopping at a different grocery store, or using your nondominant hand to comb your hair will increase your brain power.”

Hampton’s story is a mystery. The techniques promising to change her brain with an understanding of the principles of neuroplasticity have clearly had tremendous positive effects for her.

But is it true that neuroplasticity is a superpower, like X-ray vision? Can we really increase the weight of our brain just by thinking? Can we lower our risk of dementia by 60%? And learn to love broccoli?

Some of these seem like silly questions but some of them don’t. That’s the problem. It’s hard, for the nonscientist, to understand what exactly neuroplasticity is and what its potential truly is.

‘I’ve seen tremendous exaggeration,” says Greg Downey, an anthropologist at Macquarie University in Sydney, Australia. “People are so excited about neuroplasticity they talk themselves into believing anything.”

For many years, the consensus was that the human brain couldn’t generate new cells once it reached adulthood. Once you were grown, you entered a state of neural decline.

This was a view most famously expressed by the so-called founder of modern neuroscience, Santiago Ramón y Cajal. After an early interest in plasticity, he became sceptical, writing in 1928: “In adult centres the nerve paths are something fixed, ended, immutable. Everything may die, nothing may be regenerated.” Cajal’s gloomy prognosis was to rumble through the 20th century.

The notion that the adult brain could undergo significant positive changes received sporadic attention, but throughout the 20th century it was generally overlooked — as a young psychologist called Ian Robertson was to discover in 1980. He’d just begun working at the Astley Ainslie Hospital in Edinburgh, Scotland, with people who had had strokes and found himself puzzled by what he was seeing. “I’d moved into what was a new field for me, neurorehabilitation,” he says.

At the hospital, he witnessed adults receiving occupational therapy and physiotherapy, which made him think. If they’d had a stroke, that meant a part of their brain had been destroyed. And if a part of their brain had been destroyed, everyone knew it was gone forever. So how come these repetitive physical therapies so often helped? It didn’t make sense.

“I was trying to get my head around, what was the model?” he says. “What was the theoretical basis for all this activity here?”

The people who answered him were, by today’s standards, pessimistic.

“Their whole philosophy was compensatory,” Robertson says. “They thought the external therapies were just preventing further negative things happening.”

At one point, still baffled, he asked for a textbook that explained how it all was supposed to work. “There was a chapter on wheelchairs and a chapter on walking sticks,” he says. “But there was nothing, absolutely nothing, on this notion that the therapy might actually be influencing the physical reconnection of the brain.”

It wasn’t until the 1960s that the “science of the future” first began to rise to it. Two stubborn pioneers, whose tales are recounted so effectively in Doidge’s bestseller, were Paul Bach-y-Rita and Michael Merzenich.

Bach-y-Rita is perhaps best known for his work in helping blind people to “see” in a new and radically different way. Rather than receiving information about the world from their eyes, he wondered if they could take it in in the form of vibrations on their skin. They’d sit on a chair and lean back against a metal sheet. Pressed against the back of the sheet were 400 plates that vibrated in accordance with the way an object was moving.

As Bach-y-Rita’s devices became more sophisticated (the most recent version sits on the tongue), congenitally blind people began to report having the experience of “seeing” in three dimensions.

With brain-scanning technology, scientists began to see evidence for this incredible hypothesis: that information seemed to be processed in the visual cortex. Although this hypothesis is yet to be firmly established, it seems as if their brains had rewired themselves in a radical and useful way that had long been thought impossible.

Merzenich, meanwhile, helped to confirm in the late 1960s that the brain contains “maps” of the body and the outside world, and that these maps have the ability to change.

Next, he co-developed the cochlear implant, which helps deaf people to hear. This relies on the principle of plasticity, because the brain needs to adapt to receive auditory information from the artificial implant instead of the cochlea (which, in deaf people, isn’t working).

Although it took several decades, Merzenich and Bach-y-Rita were to help to prove that Cajal and the scientific consensus were wrong. The adult brain was plastic. It could rewire itself, sometimes radically.

This came as a surprise to experts such as Robertson, now a director at Trinity College Dublin’s Institute of Neuroscience in Ireland.