![]() However, unlike MX, they claimed to have had it from birth. Soon after Zeman published his results, he heard from another 21 people who said they had this condition, which he called aphantasia. He also aced other tests, such as imagining standing in his own home and counting its windows. Even though MX couldn’t form a picture of Tony Blair, he could handle tasks that would seem to require one – stating Blair’s eye colour without seeing a picture of him, for example. It’s a rare mind that works exclusively in concepts, not imagesīut then came an unexpected finding. In other words, the visual circuits worked when they had a signal from the outside world, but MX couldn’t switch them on at will ( Neuropsychologia, vol 48, p 145). However, when MX was asked to picture Blair’s face in his mind’s eye, those areas were silent. The visual areas towards the back of his brain lit up in distinctive patterns as expected. To find out how MX’s brain worked, Zeman put him into an MRI scanner and showed him pictures of people he was likely to recognise, including former UK prime minister Tony Blair. “Picturing an image in your mind’s eye is like running the system from the top down, rather than from the bottom up,” says Zeman. MRI brain scans show that when you imagine a picture of that object, the same neural pattern lights up, just slightly less strongly than when you are actually seeing it. When you see a real object, the information captured by your eyes and fed to the brain activates a pattern of neurons unique to that object: a chair has one distinct pattern, a table another. We have a good idea how creating a mental image usually works. Zeman decided to find out what was going on inside MX’s head. That changed in 2003, when Zeman got a call from a colleague who said: “I’m sending you a patient because he can no longer imagine.” The man was a 65-year-old building surveyor known as MX who reported losing his mind’s eye after heart surgery. “It was an academic blind spot,” says neurologist Adam Zeman of the University of Exeter, UK. Surveys show that most people have fairly vivid mental imagery only 2 to 3 per cent report a completely image-free mind.įor a long time, no one gave much thought to what caused this. It asks people to imagine various scenes and rate the clarity of the mental picture. Today there is a standard way to probe the acuity of the mind’s eye: the Vividness of Visual Imagery Questionnaire. But a few individuals drew a total blank. Some found it easy to imagine the table, including Galton’s cousin, Charles Darwin, for whom the scene was “as distinct as if I had photos before me”. In 1880, Francis Galton conducted an experiment in which people had to imagine themselves sitting at their breakfast table, and to rate the illumination, definition and colouring of the table and the objects on it. We have known of the existence of people with no mind’s eye for more than a century. Which ones are rotated versions of this shape, and which are not? ![]() Then scroll down and find three similar objects. To begin, stare at this shape until you can remember it. ![]() ![]() Why am I different? How do I navigate life without a mind’s eye? Could I ever train my mind to see – and would I want to? And he says the same thing now: “It’s like having a computer store the information, but you don’t have a screen attached to the computer.” That’s exactly how I feel too – and so my questions began. He spoke then of how he attributed his academic success to an unusual way of thinking, using purely concepts with no mental imagery whatsoever. So I got a shock when I saw a TV interview with Craig Venter, the biologist who created the first synthetic organism. And it wasn’t as if I have trouble with tasks that you imagine might require such a “mind’s eye”, like navigating around town or recognising friends. I have never had that ability, so I didn’t know what I was missing. At the time, I didn’t think anything of the fact that I couldn’t conjure up a mental image of my girlfriend at will. It is the same for landscapes and sunsets, parks and rivers: when it comes to mental imagery, I am blind. But when my girlfriend and I had to move to opposite sides of the US for work, we faced an obstacle that few others do. LONG-DISTANCE relationships aren’t easy at the best of times. ![]()
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