MachineMachine /stream

When the scientists tested the mind’s eye of MX, though, the difference was stark. The researchers gave all their subjects a standardized test called the Vividness of Visual Imagery Questionnaire. They asked each participant to picture things like a landscape and a friend. Then the scientists had each man rate the image that came to mind. If it was as vivid as normal vision, he was asked to score it a 5. If there was no mental image at all—if the subject knew only that he was thinking of an object—he was to give it a score of 1. Most of the men scored high on the test. MX scored as low as possible, racking up a bunch of 1s.

Della Sala and Zeman scanned MX’s brain to see if they could find the source of this deficit. They first showed him a series of faces. MX’s brain responded in much the same way as the architects’ brains did, activating a network of regions that process vision and recognize individuals. Then the scientists showed their test subjects a series of names of famous peopl