A human the size of Barbie?

In Light Sonata, Rupert’s teacher tells him that he will command his audience by becoming a giant—and Charlie wonders if cultivating such a delusion brings Rupert deeper into madness. In response, Baxter leads Charlie through the same real-life experiment shown above. 

In the experiment, the researchers trick the participant’s eyes using cameras and CCTV goggles. They route the view down the doll’s legs through the participants CCTV goggles aimed at his own legs: He sees the Barbie’s legs in the same place as his own.

Then the researchers split the visual sensations from the somatic sensations by stroking both the Barbie and the subject. After a few strokes, the subject’s brain resolves the see-feel incongruity and calculates that the doll’s legs must be his own. In his mind, he experiences himself as the size of a Barbie.

To test how much the illusion seems real to the subject, researchers dangle a cube over the doll’s legs and ask the participant to measure with his hands how big it is. The size depends not on the size of the cube, but on the size relative to his perceived body size—the size of a Barbie. 

When the researchers make the legs larger than his own, the opposite happens.