The subject was asked to pick the original location of the object in the original ocean background. (scientificamerican.com)
This sort of image can be deceptive because its apparent location doesn't match up with the actual, physical location of the object creating that image. (scientificamerican.com)
They send out noise that is returned to them in the form of an echo, which tells them the shape, size, and location of an object in question. (momtricks.com)