Ahmad Hariri stands in a dim room at the Duke University Medical Center, watching his experiment unfold. There are five computer monitors spread out before him. On one screen, a giant eye jerks its gaze from one corner to another. On a second, three female faces project terror, only to vanish as three more female faces, this time devoid of emotion, pop up instead. A giant window above the monitors looks into a darkened room illuminated only by the curve of light from the interior of a powerful functional magnetic resonance imaging (fMRI) scanner. A Duke undergraduate—we’ll call him Ross—is lying in the tube of the scanner. He’s looking into his own monitor, where he can observe pictures as the apparatus tracks his eye movements and the blood oxygen levels in his brain.
Ross has just come to the end of an hour-long brain scanning session. One of Hariri’s graduate ...
