Research shows that we don’t perceive things at the edge of our vision – and that’s putting cyclists at risk, says our cycling columnist
Apparently, we don’t see most of the things we see. Well, that’s my interpretation of some research called “The Uniformity Illusion, Central Stimuli Can Determine Peripheral Perception”. The authors are based at the University of Amsterdam in the Department of Brain and Cognition. So what does the research say?
Well, as you all probably know, when you look at something, you focus on the object and use a very small area of your retina to look at the fine detail of the object. It is something called the fovea that does this, mainly because it has lots of light-receptive cells all packed together so that you, for example, can read the words in front of you now. Surrounding this area is a much larger, much less detail-oriented, area of the retina.
The research got test subjects to look at a number of images that each had a visual illusion. For example, my favourite had lots of circles in the centre, and lots of other four, five, and six-sided symbols around. Except that when you look at the centre of the image, all the other objects around become circles as well. It is slightly freaky.
So what does this have to do with cycling? Well, ever noticed that when you are driving you can fail to see a cyclist? Or when you are riding a cycle you are almost hit by a much faster moving, larger vehicle? Well, they may have imagined that you were not there.
See, the visual system we have appears to just make up the details. Filling in the gaps in our visual field with things that it thinks are there, and ignoring the things that it doesn’t see. So, as you approach that roundabout, you are looking at the car, and the area around the fovea is not seeing the person on the cycle also coming around. And this doesn’t just apply to people on cycles. It would also apply to people walking across a side road as you turn into that side road.
Given that we probably can’t change the human brain to enhance our peripheral vision, could we make the roads safer, given this knowledge?
Well, one thing we could do is design junctions where we don’t have to look for multiple, different-sized things near each other at the same time. Roundabouts, for example, that put everybody in the same physical space.