I have written previously on how our ‘reality’ is a construct created by our brain. Only a very small fraction of what our senses perceive makes it through the various filters applied by our brain as it does its best to give us a coherent stream of consciousness. There are obviously good reasons for this, being able to focus on a specific task, like hunting for food or building a shelter, without being distracted is a good skill to have. There are some disadvantages as well, though.
Below you will find a video. Two teams of players will pass a ball between themselves, you need to count the number of passes that the white team makes. Some of you will probably know what’s coming but give it a watch anyway, it is only about a minute long.
Were you able to focus on the task? Did you get the right number of passes? Having watched the video even those of you who were expecting a gorilla should have had a bit of a surprise. The phenomenon at work here is known as inattention blindness or sometimes as change blindness. What it tells us is that there is lots that we can miss even when we are paying close attention. Indeed, the more attention we give a particular task the more likely we are to miss something going on in the background, even if that something is significant or in some way peculiar.
It works with other senses too, not just sight. Of course, we’re not generally aware of the feel of our clothes constantly on our skin, we filter that out. And it is extremely difficult for us to pay attention to two conversation at once, we generally just end up not really fully comprehending either.
As long ago as the 1950s studies were being done where two different streams of speech were being played through either side of a pair of headphones at once, one into each year. If someone is asked to listen to and repeat whatever they heard in one ear then it is all but impossible to know what is being said in the other ear. Even if the voice changes, the speech becomes incoherent or the whole language changes most people do not notice.
To clarify, change blindness and inattention blindness are actually sightly different. Inattention blindness is when we fail to notice something unexpected, like a plane in the sky in an historical drama. Change blindness is when we fail to notice an obvious change, like a car rapidly changing lanes in front of us because we’re too busy texting or having a conversation.
Most of the time it isn’t such a big deal if we completely fail to notice something that’s happening right before our eyes. There are times, however, where it could literally be a matter of life and death, like when driving a vehicle or giving an eyewitness testimony.
There actually isn’t much you can do to guard against it, either. I can’t find any evidence that there is a way to train yourself to be immune to this. The best we can do, like so much in sceptical life, is to be aware of our limitations. Be open to the idea that what you heard or what you saw was not necessarily what actually happened. Our brains are fantastic things, but they are far from perfect and knowing our own cognitive drawbacks is a vital component of being a good sceptic.