You and I see the world differently. Of cause we do, we have different believes and preconceived notions and experiences which make us interpret the sensory information in different ways. This is an extremely large and complex area of study and we are not going to go into every nook and corner in one article. Lets start small.
“what you perceive as the world is not the actual reality but a reconstruction of the world by your brain”
Lets see how and why. Lets begin with physical aspects and move on to more psychological areas. The simplest example to make you understand that you are not seeing the world as it is is the test we do in middle school when learning human eye in biology. Yes, the blind-spot. The area in our eyes which doesn’t contain any photo-receptors thus is unable to capture the light from a certain place in our visual field. No light captured, no visual information received, brain cannot see that place. But we all know that we see the world as a smooth continuous coherent picture and not a picture with a part missing.
Why? Because a part of the visual cortex fills in the blanks. Brain assumes what should be in the blind-spot and fills it in. It interpolates, so to speak. When it is binocular vision, of cause, there are other aspects at play such as information from other eye which assists brain in filling the information. That’s why at school when we tried this test we had our right eye closed and moved towards and away from the picture (~15 cm) having our left eye fixated on the cross while having the attention on the green dot.
“why does the green dot disappear and the area gets filled with horizontal bars ?”
Because the brain constructed the missing information for you. But it did it very poorly in this case. It checked for the surrounding information, when the green dot was exactly on top of your blind spot it thought “hey, everything around this missing piece is black and white stripes so middle should be that too, so i will fill it as such”
Its a completely inaccurate representation of the reality of the world. There are no horizontal bars. But our brains says there are.
“brain not only fills the missing values, it also removes most of the information from our senses”
Filling in the information with inaccurate ones is dangerous, still it happens in not so significant ways when it comes to scenarios such as blind-spots. But it is very significant when the missing parts are filled by the brain on more psychological manners. We all know that in an argument or a discussion, when we are retelling a past story from our memory, there are times when we are 100% sure of how the events went down, who said what, etc. only to later realize that a certain part of the story was from a completely unrelated but similar event. Our brain doesn’t seems to like to tell us its weaknesses 🙂 When it forgets a part of a story (a memory), it does its best to find out the missing part and even would go in to morphing a part of another memory in to the current story line. Which is fun and all when it happens in dreams, but this has consequences when its real life.
Our brain has so many tricks up its sleeves and it would take weeks to go through everything and to be fair we only know about a very little on why and how it works (no matter how much we want to say that we do.)
My favorite is the selective memory. We all do this, consciously sometimes and unconsciously most of the time. In fact this is a good thing and also a healthy aspect on its own. For one, we do not want to remember everything. And most importantly this helps to forget the bad memories thus leading to healthier lives. Whats not so good is that when in an argument or in a situation where it can be taken to our advantage, we consciously use selective memory to forget certain elements which if remembered would cost us.
“brain very quickly picks up things we do consciously and repeatedly, and try to automate it by making it a subconscious habit in order to save energy”
Yes, the brain tries to automate our repeated behaviors and thinking, by Out-Sourcing (In-Sourcing ? 🙂 ) them to the subconscious mind. Brian is about 2% of our body and still uses about 20% of the energy, thus its biologically wired to form habits. I must warn, having selective memory become a habit may not be rewarding as much as you think in the long run.
Going through all this you might get the feeling that brain is kind of an enemy. Of cause not. Everything brain does, it does for survival. To make sure the ‘host’ is free from pain and is healthy. Brain will carry out this responsibility even if it has to create, change or even delete parts of the perceived reality; which I find incredibly fascinating.
References : How does the brain fill in the Visual World (here)