Professor Daniel Simons from Central Illinois USA, works in the area of visual cognition. It’s the study of how perception, attention and cognition interact.
His work looks at how we remember visual information and how we focus on some information and not other information. What we notice and what we do not notice in the world around us.
Change blindness is the tendency not to notice changes from one moment to the next, especially when we are focusing on something else.
When Dan was at graduate school he was interested in visual attention and awareness and understanding how well people noticed changes… like a change in scarf colour or a change in set. Some people are better at detecting changes than others but the differences are not huge and we all have limits on what we can notice.
If anyone was going to be good at visual change detection, you would think it would be those who are very detail orientated. Dan has interviewed people who have made careers out of noticing change – script supervisors, working on movie sets. They are responsible for making sure nothing changes in the set. He found that it is not that they don’t detect change that much better or their visual memory is any better than yours or mine. They themselves really don’t think that they are fundamentally different. What is different about them is that they know that they don’t have a great memory. Most of us do not realise how much we miss.
If you sit someone down to watch a one minute movie they will not be able to list the 10 changes you put in the retake. Most people think they are good at change detection as they are fully aware of all the times when there was a change and they notice it, but they are not aware of all of the changes that they didn’t see in the first place. They are oblivious to all of the changes that they missed.
Script supervisors get feedback right away on whether what they thought they noticed was right or wrong – they realise that often, what they thought they knew perfectly, was wrong.
It is not the idea that we miss things that interests Dan – it is the idea that we don’t think we will miss things.
Human memories are unreliable as we don’t take in every detail around us. The bigger danger is that we trust that our memory is accurate.
There are many occasions when politicians claimed to have done something in the past and it turns out that they were lying – they may be just experiencing the same memory distortions that we all do. The difference is that they have the press following them around documenting everything that they do.
Dan wrote down in detail his memories of what he was doing, where he was and who he was with, when the attacks on the Trade Centre took place. He independently asked the three other people he was with to write out their own memories. Ten years after the event he discovered that his own memories were wrong. One of the people Dan thought he was with was actually across campus giving a talk and another was asleep. The memories that felt right to Dan were actually wrong.
We can have a very strong detailed memory that turns out not to be right. The challenge is trying to distinguish between the ones that are wrong and the ones that are right, which is hard without external evidence.
Most of the time memories are there to help us predict the future and explaining what has happened. They are great for this even if the details are not perfect.
If we see something change right in front of us, we see it because it grabs our attention. Change blindness studies break this system and by doing this we realise that we are not storing as much as we thought we were.
In a class undergraduate project, Dan wanted to demonstrate how well we can focus attention and what the consequences of doing that are. They videoed people wearing white T-shirts passing a basket ball amongst themselves. People had to count how many times the people in white passed the ball and in what different ways that was done. There were also three people wearing black shirts passing their own ball. The people had to ignore the people wearing black. It is actually a remarkable feat for the brain to be able to do this and zero in on one set of people whilst ignoring another set.
People were very good at focusing attention and paying attention to what they wanted to pay attention to. But when they focus they tend not to notice other unexpected things. The example in this study is that a person in a gorilla suit walks into the middle of the video, turns to face the camera, thumps its chest and walk off the other side of the screen.
About half of the time people did not see the gorilla.
They were so intently counting passes and ignoring those in black that they do not see the unexpected thing. You can watch this for yourself http://www.theinvisiblegorilla.com/gorilla_experiment.html
What makes this compelling is that it’s counter-intuitive because we are convinced that if something important happened right in front of us, then of course it would grab our attention and we would notice it! It is really hard to discount the idea that “oh yes of course I missed the gorilla” when their intuition is saying of course I would see a gorilla …its obvious. It is that strong intuition about what we do and don’t notice that is so powerful.
Focus is fascinating. We don’t want to be able to always notice the ‘gorilla in the room’. If we notice the gorilla we are not able to focus.
To find out if we are able to train our brain to have greater focus, listen to the full podcast with Daniel Simons, in our Resilience Unravelled Series.
You can find out more about Dan Simons on his website www.dansimons.com