Intraub Demonstration of Boundary Extension

Helene Intraub (University of Delaware) and her colleagues have studied one aspect of scene perception that she has called boundary extension. I've repeated the image above. Compare it to the image that you drew. Did you show more of the fork, etc., than was presented in the original image? If so, then you've experienced boundary extension. How might you compare this effect to the Gestalt principle of closure?