Hopefully this example will work for you. Have your head around a foot away from the screen and focus between the R and the L. Then cover your left eye and use your right eye to look at the L. Lastly, while remaining looking at the L, slowly turn your head towards the left. What you should notice is the L disappears at some point when you’re turning your head. For most of us it’s actually around the same angle of where our head ends up when the L disappears. This is where the blind spot kicks in but as you notice your mind replaced it with white because that’s what your mind saw around the L. If the L were in a blue box the L would still disappear but it would be replaced with blue.
Most people use the term blind spot when talking about driving as they’ll say they almost ran into another vehicle because it was in his or her blind spot. This is kind of strange to think about because a vehicle is so big but just like the example above, the car disappears in your blind spot and you fill in this space with the surroundings. Let’s say for example you have a lane to your left and trees along the other side of the lane. If you look to your left and a car is coming but it is in your blind spot, you don’t see the car but your brain fills in that blind spot with trees so you don’t have a clue the car is there. I think this is absolutely amazing!
These blind spots create a lot of problems when it comes to eyewitness testimonies; you’d think it would be reliable information but it often isn’t for the police. As you know there can be several witnesses to a crime with different accounts about what happened (i.e. the kind of getaway car used, what the criminal looked like, what was the criminal wearing, etc.). Some of the problem can be shock but a person’s peripheral vision and blind spot get in the way of accurate eyewitness accounts as well.
There’s way more to this topic but I hope what I shared was enough to make it interesting. Although I knew there were blind spots I didn’t really think about how they worked. The fact we create our own images to replace the blind spots amazes me.