"Subjects were presented with a photograph and then had to draw the photograph from memory. Boundary extension is illustrated in these examples, because the participants’ memory of the scene is a more expanded view than what was shown in the actual photograph. (...) They found that boundary extension is an error people make after viewing a photograph. Instead of remembering the view in the photograph correctly, they report having seen more of the world than was actually shown in the picture. (...)
Now, Intraub has found that boundary extension is not restricted solely to vision. People make this same error through their sense of touch after manually exploring a scene. (...)"