Our brain is wired to perform calculations that let us judge how far away an object is when we walk or jump around or reach for a container of milk. Although this task may seem easy, it turns out that calculating depth is surprisingly complex.
When we look at an object, our eyes project the three-dimensional structure onto a two-dimensional retina. To see the three dimensions, our brain must reconstruct the three-dimensional world from our two-dimensional retinal images. We have learned to judge depth using a variety of visual cues, some involving just one eye (monocular vision) and others involving both eyes (binocular vision).
Your brain is doing some amazing calculations as you read these words. Not only are your recognising the letters, the upright and top cross of the 'T', but you are also understanding what they mean. Imagine if you could build a computer with the same kinds of skills? Computer Scientists are looking at how our brains work to build better machines. One area where people are far better than current technology is in seeing. Around half your brain is estimated to be involved in processing some type of information from your eyes.