Personal memory can play strange tricks on us like Forgetting
Let me start by asking you a few questions can you remember what you did on the third of august 1986 I cannot see anything. but I’d like you to remember if you remember and then if you remember come and see me later or can you remember what you did this is easier closer to us what is it on the 28th of March 1992 and again if you remember and if the memory comes up like this very quickly.
Can you raise your hand can anybody remember what you did well nobody remembers and I don’t remember either and why we don’t remember well because it’s very easy to forget we forget our memory is built in a way that it allows things to go and within the first 20 minutes after learning something we have forgotten already almost 50 percent of what we have studied or acquired and a hidden in social situations when I introduced myself where I’m traduced as a memory expert.
People don’t say oh oh look what a wonderful thing my memory is I am so pleased with my memory usually people say can you help me. I forgot so much I forget where I put my keys for the car and then I forget where I parked my car and then I forget to do my grocery shopping the very essential things for the day and knowing that I do really write everything down and then I forget the list.
So can you help me and my reaction is usually I’m so sorry I’m just like you I have no hints on how to do things I might you know there are these techniques mammal that techniques that people can use but I don’t strongly strongly even them and certainly don’t help you that much remembering where you parked the car but is memory only flaws is memory only for getting no it isn’t memory is really a wonderful system that we have I think that one of the most important cognitive components of our mind.
And memory is what allows us to learn from experience memory is the skill that accompanies us from birth to death and is what makes it possible for us to know how to walk, how to turn a handle and how to ski, it teaches us it allows us to know what a table is, even how to play SimCity Buildit. But not only that it’s not just acquisition of knowledge or factor knowledge memory is also an actual knowledge that allows us to graduate eventually.
But knowledge is also about ourselves basically our memory is our identity because we are what our memory tells us we are we are what you remember about our past if we think about people with profound forms of amnesia these people not only don’t remember who I am if I talk to them that day after but they don’t remember about themselves they are lost their their identity is cut down there really are confused and it’s a very very difficult condition to live in so our memory needs to be reliable needs to be something we can count on because it makes us who we are.
And of course it is spontaneous given this condition that we trust our memories if i remember going to the movies three weeks ago with John that friend of mine and then going out for dinner and having a lamb chop and I remember the tail stop the lamb chop and I remember that it was not that happy and I remember my emotions during the movie and I remember how happy I was to go out with this person etc then all these details the vividness the emotions and the colors that perceptual details that come with a memory.
Tell me that that memory has to be true and we all I share basically a belief that our memory is like a video camera when we walk through experiences these experiences are recorded sound the visual component and they are represented that they are maintained in some parts of our mind of our brain.
They stare they stay there until we need them and when we need them we just go and pick them up and the event unfolds in front of our eyes well is this the right conception to have about memory should really trust our memories.
What 30 years of research has shown us is that actually memory is not like a video camera this is a naive conception that is based on a more widespread idea of how our relationship with the world works which is naive realism. We think that the grass is green, the snow is white but actually it isn’t there is no greenness to the breast there is no whiteness to the snow as Bertrand Russell reminded us many many years ago and a visual illusions are a good example the fact that what we see even if we believe in what we see and we use it to negotiate with the world and what we see is not necessarily what is out there
So consider for example these horizontal lines and this is a very well-known perceptual asian this horizontal lines are parallel do you see them parallel does anybody see them parallel I don’t believe so we see some zigzag with some things that are tilted go in one direction in another direction but actually trust me they are parallel we just have need to have a different frame of reference in order to see them as they are but spontaneously we see them as we see them and not as they are in reality the same thing is true for these other this is a very well-known perceptual illusion and this received these two horizontal lines of different lengths the one on the on my right is certainly shorter than the other that’s what we see but actually that’s not the way it is those two lines are exactly of equal length and I don’t have that the animation here to show.
You what you need to trust me and so as we have these perceptual illusions when we see things we also have illusions when we remember things because memory is not the way we conceive it typically memory is malleable memory and creates illusions and we live with our illusions where our entire life without knowing it so for example if i read to you a list of words and i’m going to read them thread in I sewing sharp point Rick symbol haystack Thor hurt injection and then I asked you to remember this words starting from the very last ones that are red of course.
I take the words away then you will remember sixty-five percent of you and more will remember a word that has never been presented the word needle and not only you will remember the word needle but you will remember the word needle in detail so for example half of the words are spoken by a female voice and half are spoken by a male voice you will be able to say whether the word needle was presented by a female or a man and if half of the words represented in black ink and the other half in red ink you’ll be able to say whether the word needle is presented was presented in a black or red ink and it was not presented of course you will say this is just limited to this very simple f nauman on but now it isn’t we also have a the the possibility to really change the memory of that that we have about events and about real life events.
Let’s suppose that you’re witnessing a car accident and there are two cars and then I ask you a question do you remember the color of the car of the cars that touched each other you will be very likely to report something like this but if i asked you to remember the color of the court to car that crashed into each other your memory at least twenty-five percent of the people responded that way would be more like that you’d be more likely to report and physical injuries and greater damage and even the estimation of the speed of the car that which the two cars hit each other actually would be greater in the second case then insert for first case.
This of course has this real life situations have repercussions for eyewitness testimony and that’s not limited which is something that the British police knows a very very well and they are quite ahead of time in there in their procedures are trying to keep track of that and it also happens in identifying a culprit and especially in line up procedures when you have to identify the person who actually committed the crime you make incredible mistakes and you make mistakes with great confidence because your memory tricks you at that point unbeknownst to you what we have been talking about up now is this a possibility of changing adding deleting or changing details of a memory but actually what the research has done and done a lot of work on.
This is that it’s possible to show that it is possible to create completely new memories out of nothing so if i asked you for example imagine a nurse in your mind sighs imagine a nurse nurse hair but the the face the height the body build etc etc and then imagine the nurse performing a small surgical intervention taking out a little bit of skin for a test from one of your fingers well trust me in one week couple of weeks again twenty five percent of you will remember this event as if it happened to you even if it as such it never happened to you and if I am and if I for example present dr. photos and you are here this is the real this is the real you in a real photo with your father and then there is a hot air balloon ride as you never took but I put your photo on the hot air balloon and then I show you the picture guess what again 25 percent of the people will remember a hot air balloon that never happened and in all this cases they will remember the event but they will remember the event in details and they will come up with stories and emotions and reactions in the street and then the nursery study for example people were commenting about how their mother reacted to their reactions if the mother was pleased are not pleased or you know was giving them gifts.this is not true only for lab studies it is true in everyday life there are a number of what are called crushing memories people remember events that they could not possibly remember because they were never shown.
So a number of people remember when the car in which lady diana was traveling hit the tunnel well it was never delivered that video was never show other people remember the first plane hitting the first tower at in there in a New York in September 11 again this was before the video was released but people were swearing that this is what they saw and in a recent study what we have shown is that this magic twenty-five percent of people have at least one very compelling memory for something that never happened to them and they realized they are certain that could have happened to them because these memories are about flying and aided being chased by dinosaurs.
You know being abducted by aliens well the big adapters are aliens don’t happen in England I don’t know why they tend to happen as well but anyway and even if they absolutely reject the event you know it’s impossible but they have still this is very compelling memories that tells them that you know if they had to trust their memories it must have happened so what does this series of work 30 years of work tell us that but remember is not like a video camera memory is reconstructive when we retrieve something when you try to find a memory we reconstruct these various elements that we have put in sparse and scars elements and we build on them because when we encounter an experience what we do.