麻豆传媒

鈥淭HE doubt-driven ride this book will take you on is going to physically change your brain,鈥� claims Beau Lotto early in Deviate. He wants to change our brains by making us reassess the reality we perceive.

The book draws on his research at University College London, where he studies perception, and his work at the Lab of Misfits at London鈥檚 Science Museum 鈥� an exhibition creating experiences designed to alter how and what our brains perceive.

To this end, Deviate plays with the book鈥檚 design: some words get larger fonts (making the page look like a word cloud), and occasionally pages are upside down, or columns of text run diagonally across. The intent is to shake up our very experience of reading.

The idea that our perceptions don鈥檛 mirror objective, external reality is not new. People with neuropsychological conditions provide stark evidence that we can perceive things that really aren鈥檛 there. The question is whether everyday perception is also questionable.

Deviate takes sides, aiming to convince that normal perception is also suspect. As Lotto says, 鈥淲e鈥檙e all like Alice all the time鈥� except that we didn鈥檛 have to drop through the rabbit hole. We鈥檙e already deep inside it.鈥� And he tries myriad ways to show us that. There鈥檚 the delicious story of Goethe鈥檚 ill-advised odyssey to undermine Newton鈥檚 theory of light with his own theory of colour. Goethe got it wrong because 鈥渓ike most of us, he took for granted that he saw reality鈥�.

Then there鈥檚 Michel Eug猫ne Chevreul, a French chemist who showed why the colours of the tapestries displayed in the Paris showrooms of the 1820s (鈥渞ich burgundies, grassy greens, sun-kissed golds鈥�) looked so different in the homes of customers. The perception of a colour has to do with the colours surrounding it 鈥� reality is constructed in the mind.

That鈥檚 the key idea: perception is the outcome of the brain trying to make predictions, based on experiences and assumptions that are either hardwired (over evolutionary time) or that accumulate during individual lifetimes. If we have to change ourselves, for whatever reason, then 鈥渢he first challenge is to accept everything you do is a reflex grounded in your assumptions鈥�, writes Lotto.

He reveals how to see things differently, with some tantalising insights. For instance, if your perceptions are the result of what your brain has experienced and the meanings attributed to these experiences, one way to change your future perceptions is to use the power of thought and imagination to rewire those associated meanings.

Unfortunately, the book rarely gets stuck in for long. So in the section on changing our past to influence our future, he writes: 鈥淕overnments 鈥� especially totalitarian ones 鈥� and their spin doctors understand the power of re-meaning history鈥�. But in two paragraphs, he has moved on to big data.

鈥淥ne way to change future perceptions is to rewire the meanings associated with past experiences鈥�

Deviate can wander into pop psychology, as when Lotto talks about how living purposeful, creative lives means having to embrace uncertainty. He even dispenses relationship advice: 鈥淲aking鈥� with another needs to be like seeing a sunrise.鈥�

In the end, Deviate can鈥檛 quite make up its mind if it鈥檚 about the neuroscience of perception or helping us change our lives using neuroscience. The tension is best illustrated when Lotto discusses how hard it was to apply his neuroscientific knowledge to make sense of an illness causing him neurological problems: 鈥淵ou know too much and nothing.鈥�

This article appeared in print under the headline 鈥淪eeing is not perceiving鈥�