 Hi, and welcome back to this video in the biological psychology video course in this video video 4.6 We're going to take a look at the reliability of memory now So let's start with a quick memory test. So here you have a list of 20 words 16 words actually so take a moment to to study those words. I will give you I will give you 30 seconds And time is up Okay Now before we're going to quiz you on the actual words that you've just studied Let's ask ourselves. What kind of working memory? What kind of memory are we testing here? Now? Is it sensory memory? If we think back about the Second video in this section then we know that sensory memory has maybe one last only one about one second, right? It's sort of the after effect of visual or sensory Information so it's clearly not the case here right because one second has already passed for For a while then working memory Well working memory is sort of the idea that you keep in few items from your sensory memory in your working memory And you actively rehearse them is that going on here? No, not really because in order to study this kind of list I did these kinds of lists with many many items on them You really need to transfer them into long-term memory and that's actually what makes it so difficult, right? That you need to rehearse them rehearse them until you they're not no longer in your working memory, but they have been transferred to your long-term memory Now so how successful were you in transferring those items to your long-term memory? So which of the following words were actually in the list hill? Causes sleep hard tired mountain so think for yourself Which of these items you remember right that were in the list Now let's take a look which actually were in the list Only hill and tired All the other items were not in the list If you do this experiment and I've done it a few times in class and it works Reliably reasonably reliably well a lot of people tend to misremember sleep and mountain as also being in the list Why well because the list had a list had a lot of words related to sleep and related to mountains in it Although the word actual word sleep and mountain were not in the list, right? So you sort of get a false alarm So more generally this is a false memory that happens when people would study a list with a lot of words that are related to sleep For example, but not the word sleep itself Then they very often tend to think that sleep was in the list to actually form an a false memory of the word sleep And now this shows how easily our memory can be fooled All right It is the fact that this is such a reliable way to trick people into Forming false memories just by having them study a list of words is a little bit disconcerting right it really makes you question The reliability of your own memory and you should question the reliability of your own memory because it is not nearly as reliable as you probably think Yes, so this was actually a classic study done by Henry Rudiger and Kathleen McDermott. So now so Let's take a look. So now we've given I wanted to start with kind of a fun example of a false memory But let's take a look at a few different ways in which memory can go wrong Let's start with amnesia. So amnesia is the term that you use to describe an impairment of your long-term memory Because of disease for example dementia, right if you have Alzheimer you start to memory starts to degrade Physical trauma if you have brain damage, right? For example, if you've had a car accident, you might have memory problems Psychological trauma, right? So for example, if you're depressed depression is also accompanied by memory memory trouble Yeah, so that all of those things those are called amnesia, right? So they're sort of unhealthy They're sort of a disease-like impairment of your memory due to whatever cause Now what kind of amnesia do we have say that you someone has suffered brain damage to a car accident, right? So physical trauma that really physically this did damage the brain then you it's very likely that you have memory issues Now say that that person cannot form new memories after the incident then you would call that forward amnesia or enter a great amnesia, right? So if that and that is actually for example, what happened in the very famous movie memento When when the the lead character in the movie was no longer able to form new memories So he had he had come he had in order to sort of survive He had to continuously keep give him may write notes for himself, etc in order to sort of keep track of what he was doing Very good movie actually memento Yeah, so this reflects an impairment of memory and coding right so because you you you have to you have of course you get new Perceptual information you have new things in your working memory all that can work fine But it is just not encoded consolidated into your long-term memory, and that's why you have forward amnesia Now what can also happen is that after that the that person is no longer able to remember what happened before the accident and then you would call that backward amnesia retrograde amnesia Right, and that would be an impairment of memory retrieval because at some level probably the all of the memories be from before the car Accidents are actually present at some level But due to the brain damage that person is just no longer to be able to retrieve them, right? And that's why you get backward amnesia so forward and backward amnesia are two common ways to sort of describe what Which parts of your life are essentially affected by amnesia? so Amnesia is not a healthy condition right if your amnesia something is wrong, but even if you are healthy even even you and I assuming that we both healthy is Does not mean that your memory is reliable right memories are often distorted in or lost in a lot of different ways So let's take a look at a few things in which health few ways in which healthy memory can be Distorted or lost the first is just that you can forget things So even when you have memorized something and you've stored it in long-term memory So for example a list of French words that you studied in high school, right? That was at some point in your long-term memory, but if you've never rehearsed it, it's probably gone by now Because memory is gradually fade away Unless they are refreshed of course if you if you live in France, you are not going to forget your French words, right? But if you've studied them in high school and now you're living in in Norway Then you will probably forget them So what you're seeing here is the famous forgetting curve by Herman Ebbinghaus a very classic Psychologist and what he did is basically memorize nonsense syllables himself He studied these studied in his own memory and then tested himself at various points later in time and then he found that say Immediately after testing right he was a hundred percent perfect because he had studied the syllables until he knew them by heart And then 20 minutes later he knew only 60 percent and then it gradually declined until like after one month He remembered only 10 percent of the of the words of the syllables that he had studied, right? So and this is kind of this gradual forgetting curve that affects all of us So you forget stuff of course Then there's also the misinformation effect Now this is a very famous experiment by Elizabeth Lothis and one of the main I would say main researchers on on problems in memory And in her experiment, she she showed a video of a car crash to participants the same video all participants saw the same video But then they were asked a different question afterwards So they asked either how fast where the cars going when they smashed each other So and then the verb smashing really suggested that we're going very quickly, right? We're very fast or how fast where they cars going when they collided each other, right? Not really that fast and then or how fast where the cars going when they contacted each other, which is pretty gentle, right? They kind of So the basically this the question was very means it was leading right it suggested The answer was essentially already in the question and then what participants said, okay? They said they asked participants to to rate the speed of the cars, right? And you see if they use the verb smashed implying a high speed then participants said that the cars were going about 40 41 Miles an hour Whereas if they use the word contacted in the question participants said they were going the only maybe 33 miles An hour, right? So basically the speed that was implied by the question was Absorbed by the participants and became part of their memory in a sense, right? Yeah, so participants estimated faster speeds when the question used a fast verb like smashed compared to a slow verb like contacted Now so this shows that leading questions can shape our memory and it's called the misinformation effect Now I don't really like to term the misinformation effect that much because it suggests that there's something wrong with it, right? I think another way to think about these kinds of effects is that generally speaking There is there actually is a valid information in the things that other people say to you, right? In this particular experiment the question has no valid information in it But in real life if someone phrases Says something to you using the word smashed then the fact that that person used the word smashed Suggests that there was something very smashy about the situation Whereas if that person used a different kind of work like contacted that suggests that it was a fairly mild situation, right? So you of course if you are a reasonable rational person you would use the information in the question to To sort of form your own memories, right? So I think it makes a lot of sense essentially to have leading questions shape your memory and in most situations That's a healthy perfectly normal thing to do It just means that our our memory is very Susceptible to being affected by things also when we don't want it to be the case, right? So it's it's often called a misinformation effect But keep in mind that it's misinformation effect is no me by no means in all In all ways a bad thing Now Then there is the tourney issue of uncovered memories. So Is it possible to? Forget something that happened and then later recover that memory And that is very tricky because this tends to happen in situations where you actually have no ground truth, right? For example, the most the most stereo most common scenario would be that someone remembers sexual abuse from childhood, right? So then we don't really know whether it is possible to really forget that kind of sexual abuse And if you can forget it whether it is able to recover whether you're able to recover it, right? And we because there is no ground truth. We cannot really verify What what was really going on that makes these kinds of situations very very difficult So is that an uncovered memory or is that a false memory? We know that false memories are possible So whenever someone remembers something that happened suddenly recovers a memory There's the possibility of it being a false memory that I think is pretty clear But that does of course not mean that it in all cases is a false memory It might also be a true memory and how can we ever find out? So we cannot be sure I Would like to say that a lot of researchers including Elizabeth Loftus are skeptical about the ideas that you can Uncover memories, right? So there's I think some dose of skepticism is warranted But especially when it because this can be a very sensitive topic I think that you should be also skeptical with a certain Appropriate modesty because you don't really know So let's take a look at a few cases of Recovered memories of sorts I would say so stir Bergwall was actually pointed out to me by a student last year He confessed to 30 murders during memory recovery therapy therapy now What is memory recovery therapy? It's basically you sit down. Well, that's my understanding of it Is that you sit down with the therapist and the therapist helps you to recover a memory now? That is a very dangerous situation because it you know The suggestion of that you need to recover a memory will make a lot of people recover a memory Whether it is there or not right so there's a high risk of false memories And that's why memory recovery theory theory has a very bad name rightly so I believe So he confessed to these 30 murders and later retracted his confessions, and he was actually cleared He did not actually kill all those people Now why what happened here? I don't really know of course only information that I have on the newspaper's articles newspaper articles on it But this seems to be a mix and I think this is quite typical a mix of different Different factors different psychological factors that sort of have relate or somehow related to memory So I think maybe partly he actually had false memories so that he he was a very disturbed man, right? So the suggestion of him having done all those murders. Maybe he believed it He also had a certain desire to please because if you are in you know, you're in you want to be liked Everyone wants to be liked I so if you're if you're if you're if a police officer is questioning you and really wants you to To confess to a certain murders Maybe you will just confess to make you know to be liked by that that police officer and that last thing was actually At least some what supported by this particular quote from him in which he said I think this is a this is quite a gripping a quote I was a very lonely person when it all started I was in a place with violent criminals because he was already in jail And I noticed that the worse or more violent or serious to crime the more interest someone got from the psychiatric Personnel, so he was essentially jealous of the people who have done horrible things because they got a lot of attention. I Also wanted to belong to that group to be an interesting person in here And that's when he started to confess those murders, right? So there's a lot of things that drove this person stir a burglar probably to confess to things that he did not commit having to do At least in part. I think with false memories, but we don't know really what happened another situation case I Quite recently occurred on Dutch television if you're Dutch, maybe you know it Is that the giet op de beek a very famous Flemish writer right in a Flemish writer also writes Dutch So I actually read a few of her books very good very good books She announced on on prime time television that she had rediscovered that she had been sexually abused as a child That this was she actually did not describe this as a recovered memory. She said that she did not really Remember it, but she had discovered it based on indirect cues that she did remember. That's the way she talks about it Now and with help from a therapist There was not really any direct evidence as far as I know to support her claim Which of course and I always think it's important to point it out That does not mean that there's any evidence to suggest that that she's not that her memories are false, right? There is just no evidence either way And I think this is a very This this this is a painful to me when I was watching it on television. This was a painful Fragment to watch because it is clearly something that is very emotional to her regardless of whether it is true or not She got a lot of criticism also on it in the media right people questioning her and etc And so how do you approach such a charged issue right? There are a lot of things involved here On the one hand, I think it is to some extent important to know the truth, but also her personal feelings are involved It's also I guess if you really Accept her confetti her discovery in question unquestioningly then you might encourage other people to form false memories, etc So there are a lot of different conflicting conflicting things going on here And I find this yeah Important to think about I don't personally know how you should deal best deal with these kinds of situations, but They do happen right and and they are importantly they happen because our memory is so Valuable so imperfect leading to these kinds of very difficult situations Now with that we've come to the end of this section on on memory in the biological psychology video course Thank you very much for watching