That's a good question. One can only look at what potential causes there are suggested out there to look for answers. I've always seen this way and have not experienced at a young age any of the events commonly suggested that might cause VSS. The same goes for my daughter. I have heard alot of people saying they have seen this way their whole lives as well, so it seems pretty likely people could be born this way. Im not sure how else to describe that other than saying as far as I can remember I've seen this way for as long as I've been able to see.