Some of them are involved in decision making, others in memory or vision. Generally, when people are asked to visualize a person, place or object, a network consisting of various brain regions is activated. In most people, the more that objects differ in their orientation, the longer it takes to mentally rotate them to see if they might match up.įunctional magnetic resonance imaging (fMRI) supported MX’s claimed inability to produce a mental image. Yet in contrast to the control group, he took longer to decide, and the time he took did not depend on the degree of rotation. He was shown two pictures of three-dimensional objects and asked to say if they were the same item, pictured before and after being rotated on its axis, or different objects. He also did fine on a test of the ability to rotate objects mentally. MX correctly said that pine trees are darker than grass, but he insisted he had used no visual imagery to make the decision. Surprisingly, though, he was able to accomplish tasks that typically involve visualization.įor example, when asked to say which is a lighter color of green-grass or pine trees-most people would decide by imagining both grass and tree and comparing them.

Compared with control subjects, MX scored poorly on questionnaires assessing the ability to produce visual imagery. Zeman and his colleagues began their analysis by testing MX’s visual imagination in several ways. And he and others are exploring its neurological underpinnings. He has since given the condition a name-aphantasia ( phantasia means “imagination” in Greek). Zeman had never encountered anything like it and set out to learn more. He could see normally, but he could not form pictures in his mind. But after undergoing a procedure to open arteries in his heart, during which he probably suffered a minor stroke, his mind’s eye went blind. All his life, MX, a retired surveyor, had loved reading novels and had routinely drifted off to sleep visualizing buildings, loved ones and recent events. The patient, later dubbed “MX,” claimed he could not conjure images of friends, family members or recently visited places.

In 2003 a 65-year-old man brought a strange problem to neurologist Adam Zeman, now at the University of Exeter in England.

Not being able to visualize things