Sudden Drops

As stated by Berger (2011), some infants can see a sudden drop at as young as three months old. Before that scientists believed that children could not see different variations in depth perception due to their decreased maturation of their vision. I think it's interesting how some of the children even at six months old can be persuaded to crawl over the "sudden drop" despite the fear of falling, but the old the child gets, the more they learn that just because their parent is calling them, they fear falling and getting hurt. Therefore, the baby is already learning to problem solve and chose safety over praise from their parent. My question is why do some infants see it as early as three months but some not until six months or later? Is it because the younger infants have already fallen off of something so they have learned to look and take in their surroundings more? Or has their depth perception just matured faster than other children's their age? I find this very interesting and wonder how it relates to my own fear of falling. I always say I don't have a fear of heights I have a fear of falling. I wonder if as a child I fell off of things at a very young age and that has caused my fear. From reading the text I would have to believe that my fear of falling goes back to when I was a small baby, and something must have happened in order for me to have this fear.

Reference:

Berger, K. S. (2011). The Developing Person Through the Life Span. New York: Worth Publishers.