Mexican author Don Miguel Ruiz once said “We only see what we want to see; we only hear what we want to hear. Our belief system is just like a mirror that only shows us what we believe.”
The idea that we only see what we want to see is quite a common one. This is because it is neurologically true. In fact, what is neurologically true is that we only see what we expect to see.
Everything that our eyes see is transferred from the retina to the thalamus, which acts as a sort of translator or processing centre in the brain before sending the information to the visual cortex. The visual cortex, however, sends back input into the thalamus to be used in that process and, importantly, the visual cortex sends much more information to the thalamus that the thalamus sends to the visual cortex. The thalamus also receives input from the brainstem, information related to mood or affect. Although the input from the retina to the thalamus is the clearest one, it is only a minor part of what is then transferred to the visual cortex. In reality, the visual cortex received back a lot of its own input. This is why we end up only really seeing what our brain had expected to see.
Like a lot of things that go on in our bodies and brains, there is an excellent evolutionary reason for this to work that way. As we developed from a newborn into a child and then an adult our brain was designed to focus on keeping the most emotional memories - those related to pleasure and pain. Our memories are made primarily about emotional events, events that are useful to our survival. If we clogged our mind with memories that are of no evolutionary use, we probably would not be very good at surviving. These memories, which are stored all over the neocortex, are part of the input that the visual cortex sends to the thalamus to help it process the stuff the retina has sent as fast as possible, but this can often mean it is inaccurate, or rather biased.
The good news is that the brain can be relatively easily trained to spot something new. The “Where is Waldo’ series of books are an excellent example. The first time it takes you ages to find Waldo but eventually, you spot him very fast. This is the same thing for hunters, for example, or safari guides. They have trained their brains to pick up on, say, a lion, which would be almost impossible to see for someone else.
The bad news is that it makes us less good at spotting things are we not looking for, or to fight so-called confirmation bias which is the tendency to interpret new evidence as confirmation of one's existing beliefs.
To make things worse, today we tend to use our senses - sight, hearing - much less than we used to. Back in the caveman days, if we didn’t spot a predator we would probably die. Today, we can walk with our eye riveted on a screen and music blasting in our ears and (most of the time) we’re safe. We can afford not to worry about spotting new things and also we are increasingly in control of what we expose our senses to.
This is where interacting with nature and animals can really help us learn to see, and hear again. Most animals, even domesticated, are still very much in tune with all their senses and rely on them for their survival. Your dog, your cat or even your horse for that matter spend hours every day just observing. Something we need to relearn.
This was written based on the Chicago curriculum ‘Neurobiology in everyday life’ which you can find here.