Most of us, whether we admit it or not, have played with dolls at some time in our lives. When we did this, we thought our way into that small world, but we rarely stopped and tried to imagine what our world would look like to Barbie and her friends. As an adult, we may have visited a house or a school that we haven’t seen since we were very small. The usual impression is that it’s much smaller than we remembered.
As we sit around philosophizing in our armchairs, we say of course, we were small then, but we know better now that we have rulers to measure things properly. Now we know exactly how big something is. That horse over there is 16 hands, for example. But whose hands? My delicate, skinny ones or those belonging to that big guy over there whose hands are wider by at least half as much again?
Our size still effects our perception as van der Hoort et al from the Karolinska Institutet have shown (1). They took nearly two hundred willing and naïve participants and convinced them by using cameras and TV screens that their bodies were any size from Barbie to Beanstalk Giant size. I stress here that naïve is used in the psychological test sense and not in the sense that my Mom used when I bought my first car for twice as much as it was worth. These participants were all between twenty-five and thirty, so weren’t likely to be fooled by any used car salesman.
How were they convinced of their new body size? The cameras showed them the lower half of their bodies, that is, jeans and sneakers, while the experimenters were touching their ankles. The TV screens showed different size objects touching their ankles, thus convincing them that they were either from Lilliput or from Brobdingnag. The participants then had to judge the size and distance from them of a box-like object.
The results? In Barbie-mode the participants thought that the box was larger and farther away than it actually was. If in Beanstalk Giant-mode the box was thought to be smaller and closer than in the real world. The authors go on to indicate how this could have important applications in the field of tele-robotics. They ask us to imagine being a surgeon and having the full body illusion of being a microrobot inside their patient and hacking away at that person's internal organs. Anyone who has dug through a water main in the garden by mistake will shudder at the prospect of hitting a capillary.
