MARK L HOWE: I'm going to talk today about some research that's both, I hope, scientifically rigorous but also translational in terms of the forensic venue. Before I start to talk proper though, I do want to provide you with a little, as Chuck was alluding to, some UK context for what's going on in the UK. There's been, unfortunately, a resurgence of historic child sex abuse cases in the UK. Dare I say, a renaissance of such cases now.
So it started with historic child sex abuse charges that came about for this person named Jimmy Saville, who was dead at the time. But they're cases from the 1970s. This is a picture of him. He used to host a show called Top of the Pops, which is a big UK show where all the top hits were portrayed or played every week.
He did a number of other things. He used to do visits with children's hospitals and a variety of other institutions. And he was arraigned on a large number, or his estate was arraigned, I should say, on a large number of historic child sex abuse charges in which, of course, he was found guilty, OK, of every single one of the cases.
There was very little, if any, physical evidence in any of these cases, because they're so old there. There wasn't any evidence collected at the time, but there were so many people who testified about what had happened and so on that the courts decided that this was an important thing, and therefore that he was guilty.
Now, the problem with this was that there were several TV shows following this and that were broadcast in the UK in 2012 about historic child sex abuse, and sort of flag on it if you have been abused by this man or any other man, you should come forward and tell us all about it.
There was a BBC Panorama. Panorama's a sciencey show over in the UK that broadcasts a lot of things that are allegedly true, according to the public. They believe it all. And again, this call was put forward and the national site for prevention of cruelty to children also opened a help line called Actioning Voices, if you will. And within the space of about six months, there were 500 additional cases on the books about child sex abuse.
So we go to people such as Bill Roach, who is-- those of you who watch Coronation Street will recognize him. He's an actor in Coronation Street. He was brought through the courts as well, but he was found not guilty. Then we had Max Clifford, who you may recognize. He's a publicist. He used to represent people, a number of different people, including Frank Sinatra among others. And he was charged with sex abuse as well, and he was found guilty.
And most recently in the UK, and I mean, there's many, many other cases like this, but most recently in the UK, we have Cliff Richard, for those of you who remember the '70s. And he's now been charged with child sex abuse, [INAUDIBLE] and of course, this is now an ongoing inquiry.
Now, as I say, there are many other individuals who have been charged recently with these types of crimes, and one of the things in the UK that may have spurred this on, that you may not know, is that the government will pay you if there's a criminal conviction.
So if you are a complainant who has suffered this childhood sexual abuse, you can get paid by the government up to sometimes over six figure compensation packages. So there is another motivation for doing this. And some of the cases, some of the history of the previous cases the people were found not guilty, some of the people made claims that the person had sexually abused them, and they never met the person, never been in the same city as the person ever.
So there's other sorts of motivations behind this. Now, there are also some more recent cases that have happened. This is a case in Rotherham police station, which is a small satellite community in one of the larger centers in the UK. And there have been-- this is the headline. Police chief at the time with child sex abuse claims has been threatened with death threats. There's a whole huge controversy about this right now.
There are 1,400 children that were sexually exploited over a period of 16 years. These guys went out and groomed the children. A lot of them were runaways and kids who were poor. And they groomed them, and then they turned them into prostitution rings and so on.
Now, the horrible thing about this case is that these charges were brought at the time by the children. So they saved the clothing. They saved other evidence of what had happened to them. They brought them to the police, and the police either said, we're not interested, or they took the evidence and subsequently lost the evidence.
So there's a huge scandal about this now. One woman has come out and said that she was writing a report at the time about these charges, and that the police had told her to whitewash her report, which she then did.
So these are cases where there is documented evidence that sex abuse did happen. So it's not that all of these cases are false. There are a lot of that are, of course, true.
The other situation is-- another case that's just come up in Northern Ireland during World War II, kids who were in orphanages at the time were then subsequently shipped off to Australia, where they were abused in Ireland, and of course abused in Australia.
And now there's, I think, 300 witnesses are now taking part in this particular case, too. Here, though, there is no physical evidence of what happened. So again, it's all going to be memory-based testimony.
So what I'm going to talk about today, given this context, is very critical in the UK, and I'm sure it'll come back to resurface in North America as well, from time to time, is the problem of what do we do when we have evidence that's memory and generally speaking, only memory?
How do we tell whether it's-- how do jurors and judges tell whether this is correct evidence, whether it should be admitted in first place. And secondly, if it is admitted, how to interpret that evidence and come up with a decision as to guilt or innocence?
So the problems are at least twofold. First is that memory is reconstructive. So that what we do is we have a fragment, perhaps of something that might have happened, and we bind it together with things that are associated with that memory but didn't necessarily happen. The problem is, can we tell which is the kernel of the memory and which is the fabricated or reconstructed part?
The second thing that we have to worry about is how do we convey this information about the reliability or unreliability of memory to people who are in charge of trying the facts? Not just trying the facts, but also the police who first interviewed the complainant and decide whether a case should go forward or not. And if a case does go forward, how do people who are trying the case now decide whether the evidence is good, bad, or indifferent?
So that's the basic structure of the talk. There is talk again. Now this is talk proper. This is the related paper that is available. And this is loosely based around this particular paper. OK, so memory in the law. So memory provides key evidence in a number of settings, a number of proceedings, not just historic child sexual abuse. And it begins, of course, with the police or somebody taking a witness's or a complainant's statement about what happened.
It's then followed by eyewitness identification of people in a lineup, and which we know quite a bit about and I'm not going to talk about today, because that's a whole different chat. And finally, it ends in the courtroom, where the complainant then talks about what the perpetrator allegedly did.
So memory comes into play at all different stages. And the justice system needs to be concerned not only with about what witnesses can remember and the reliability of their memory, but also what triers of fact, judges, jurors, know about memory.
So the science of memory is not well-known to most judges or jurors, of course, as we know. So the question arises, how do we get triers of fact to actually evaluate memory evidences, like DNA evidence? If you don't understand what DNA is all about and somebody comes in and gives you some DNA evidence, you need an expert to come in and tell you what the DNA evidence is about.
Same thing with memory. People provide memorial evidence, somebody needs to come in and tell people what is memory, how does it work. So to answer this question, let's take a look at some of the typical scripts that I get sent to me all the time.
So here's complainant number one says, "I was upstairs, and I was playing in the spare room and I was a bit upset. I was wearing my favorite pink dress, and I remember him coming up to me, and he just picks me up. And he just sat me on his lap and gave me a really big squeeze. He was wearing jeans and a t-shirt, and would just sit there with his legs straight down in front of him.
When he picked me up, he would sit me facing the same way. He just pulled me really close to him. He had his arms around my waist. I remember feeling uncomfortable."
Here's another complainant from another case. "I was in the house alone with him a lot of the time, and he would take me into his room. He had us green solid pressed wood headboard and blue flannel sheets on his bed. He would just lie there on top of the sheets, just sitting up on the bed with big feather pillows behind his head, and just lie me next to him to his right.
And then I remember him. He was rubbing himself with his right hand. And then he would say, 'why don't you feel it, too?' I remember looking at him, and then he would take my left hand, and he would make me completely grab it and pleasure him. I remember thinking, 'this is disgusting.'"
Now, although such detailed memories are entirely possible, under certain conditions, these recollections are of events that occurred some 30 years earlier when these people were three years of age. So not only are these complainant's narratives unusually rich in detail, which we don't see-- I'll get into this in a bit-- they also contain concepts not normally available to children so young. For example, handedness, left right, disgust.
So more often, these unusually detailed memories also include verbatim conversations. OK. Things that not none of us could really remember. My verbatim conversation with Chuck a couple of days ago, I have no memory of it. I just have the gist.
So these types of things are what I like to call remarkable feats, F-E-A-T-S, of memory that occur in the courtroom only, and we've never seen them in the lab. So the problem is that in the courtroom, when memory serves as the main or only evidence, like in a historic child sex abuse case, how well equipped are the triers of fact in evaluating such evidence?
Because oftentimes, triers of fact believe that the more details you have, especially perceptual details you have, and the more you can talk about things that people were wearing, where people were, that this is something that is a sign that they're actually having a real memory. When in actual fact, of course, what I'll argue is that it should be a sign that we need to be skeptical of said memory.
So one way to assist triers of fact would, of course, to call on a memory expert. However, recent decisions in the UK and the US have suggested that such expertise isn't needed. So we have a UK judge who said that "it is difficult to see how expert evidence can properly be tendered to establish a justifiable criticism of an adult witness who says that she suffered abuse throughout her childhood, which must have begun at too early an age for her to remember the first occasion and who provided highly specific details of abuse at such an early age.
The jury should consider their own experiences, searching their own recollections for earliest memories and analyzing what they could actually remember, and how far back their memories went. They did not require and would not have been assisted by the evidence of an expert."
So the implication here is that jurors would look back into their memories. And because they have not had a traumatic experience like that, will then say to themselves, well, I can't remember back that far maybe, but if I had been traumatized, you betcha I would've remembered that. So we don't need anyone to tell the jury that. That's what the judge assumes that we know.
In the US, it's just one of numerous cases. Eyewitness testimony has no scientific or technical underpinnings, which would be outside the common understanding of the jury. Therefore expert testimony is not necessary to help jurors understand eyewitnesses' testimony.
So we seem to have some areas in which judges don't want expertise. So perhaps these judicial remarks should be taken seriously. So the next step, if we're going to take it seriously, is we need to know what triers of fact do and don't know about memory. Maybe they do know all this stuff about memory. Maybe all the memory courses that people have in taking colleges have actually paid off and everybody knows everything you'd want to know about memory.
Of course, unfortunately, when we take a look at these naive beliefs, we see that people's common sense understanding of memory is woefully at odds with what this talk is going to be about, what we know in the scientific literature.
For example, in a relatively recent study by Benton et al. in 2006, they asked participants who were either law enforcement, police, judges, potential jurors, and memory experts. So they asked them a series of questions. I'll just highlight a few of them that I think were interesting.
So the first question is about forgetting. So "the rate of memory loss for an event is greatest right after the event and then levels off over time." So the figure depicts the percent agreement with this. And of course, it's true that that's what happens. And all three non-expert groups were reliably lower than experts, which you told.
And of course, 83% is kind of a scary number there, too. I'm not sure who the experts were. They were supposed to be [INAUDIBLE]. So what we have is people who are triers of fact and people who are judging whether police should-- or judging whether a case should go to court or not don't have that information.
So what that means is that they maybe think that forgetting occurs much later and that you can remember lots of stuff for long periods of time. Next question, false childhood memories. "Memories people recover from their own childhood are often false or distorted in some way." Typically true. Can be. So you have to admit that.
Now, of course only 68% of the experts said that could be true. And the other two groups, law enforcement and the jurors, were below that, significantly below that. And judges were as good as experts on that particular question.
So something has happened, anyway. Some judges seem to understand about false memory and childhood events. And then the favorite question is long term repression. So "traumatic experiences can be repressed for many years and then recovered." So as you can see, the three people who were triers of fact or adjudicating memory evidence all think that that is pretty close to true.
I don't know who the 22% of experts who thought it was. But anyway, that's just some indication that, gosh, these commonsense, naive beliefs go against what we've developed in the scientific literature. And these are the people trying these cases.
As a lawyer said to me one time-- I said, what would you do if you were ever charged with childhood sexual abuse? He said, "I'd empty my bank accounts and I'd go somewhere really nice in South America." So right. A more recent study by Patihis and colleagues in 2014 examined undergraduates-- this is like a science paper-- examined undergraduates' beliefs about memory.
And note, the people from this population would not only be jurors, potential jurors, but they would also be considered educated jurors in this context. So the following table contains some of their answers to questions about memory in the courtroom.
So "trauma memories are often repressed." 81% agreed. "Repressed memories can be retrieved in therapy accurately." 70% of people agreed. "Hypnosis can accurately retrieve memories that previously were not known to the person." A little under half the people believed that to be true. "Memory of everything experienced is stored permanently in the brain, even if we can't get access to all of it." 67% of people believe that. And "With effort, we can remember events back to birth." So that was kind of the lie question there, right? Only 15% agreed with that.
So they also asked these same questions to practicing clinicians of various sorts. These include clinical psychologists, psychoanalysts, and NLP therapists, hypnotherapists and internal family systems therapists. And here are some results for the two best questions that are relevant to the courtroom.
"Traumatic memories are often repressed." Over 3/4 of the people believed that to be true. "Repressed memories can be retrieved in therapy." A little over 50% of them believed it to be true.
So these are just some examples. There's lots and lots of other examples from all over the world, studies in Norway and Sweden, et cetera. Even Canada. So some examples of the naive beliefs that people hold and clinical practitioners, jurors, serving judges and so on.
And so this is a huge disconnect between what we know about memory and what these people believe about memory, and that's how they're making their decisions. So how do we reduce this disconnect? So it isn't true that common sense prevails. I mean, common sense does prevail, but it's wrong in these cases. So what do we do in order to prevent this from infecting our courtrooms?
Well, one of the things we have to do is, we have to distinguish myth and fact. And we have to make this known to the people who are important. Again, the police, judges, jurors. So first, peripheral information. As my examples indicated, there's lots and lots of peripheral information that is included in courtroom transcripts but also in transcripts of the police collecting interviews that is contained in the statements.
So it's well-known, of course, that long term memories typically consist of core details, such as "I was fondled" at the expense of peripheral information, such as "it was a sunny day. I was wearing aqua colored underwear. I had scrambled eggs for breakfast. My dad was outside cutting the lawn."
Of course, there are exceptions to this. I'm not saying that there aren't. But the majority of what is called 30 years after a childhood event has more to do with the meaning of the event or gist of the event and core details of the event than what the weather was like, what you were wearing, where other people were, or what you'd eaten earlier that day.
Now, curiously, for me anyways, it's often the presence of these specific details that lead triers of fact to believe the complainant is telling the truth rather than seeing it as something in need of being skeptical of. In fact, it's one of the things that the police often use, not only in historic child abuse cases, but also in rape cases and asylum-seeking cases, too, is whether you have all these types of details.
Verbatim conversations. We see this all the time. I'm also surprised to see the complainants' testimony that forensic interviewers actually ask questions, "can you remember what he said? Do you remember what he was wearing? Do you remember what you were wearing? Do you remember how big it was? Do you remember whether he wore a condom?"
All these types of very specific details. These are things that, depending upon the age of the child or the person, is unlikely to be encoded in the first place, let alone if it had been encoded in the first place, be remembered later on, when you're an adult.
So it also strikes me as odd that the complainants do remember these details when requested to do so, but also remember much more. So I have one case in which a complainant not only remembered what everybody was wearing and where they were in the house at the time she was allegedly raped, when she was 6 years old, but she also claimed to remember exactly what the perpetrator said.
She said, "he told me to keep watching TV. Don't tell anyone I did it. Nobody would believe you. It's our little secret. And you don't want your mom to call you a liar and things."
Now, these are very familiar types of things. We get this in almost every case. And so it's sort of a I'm not sure where it comes from. I have a guess as to where this type of conversational material would come from. But this woman only remembered these events following extensive therapy, bad therapy, too, imagination inflation stuff and so on.
So these things came back to her, these conversations came back. In fact, they were coming back to her during the interview. She says, "oh, I just remembered another conversation that I had. Yeah, and he said this."
So on the other side of the coin, we also see in many of these cases that there are missing core details. So they recall lots of peripheral information, but they forget some of the core. Although it can be difficult to say what's peripheral and what's core information, we can all argue about that, I would argue that a description of the perpetrator, particularly if the alleged abuse happened a number of times, should be available to the complainant.
So here's a case where one complainant had considerable problems remembering what her alleged perpetrator looked like. So the interviewer asks, "how old was he?" And she says, "oh, about 20 or 15, or 13, or 16. I don't know." Which is the good answer there. When asked what he looked like, she said, "I can't remember."
When asked what his hair was like, she said, "all spiked up or just normal. I don't know." When asked what color his hair was she said, "it's blonde or black or red-brown, or just bald without no hair." And this went to trial. Who's doing this? Now, why are they doing this? Sorry. I'll get off my box now. But it's just absolutely mad.
And I mean, I'm not just drawing out, this is the one case out of the billions that are around. This is fairly frequent, these types of things. Curious concepts also appear in these types of testimonies. So when recollecting childhood experiences, these should contain age appropriate information. The language and concepts being used should correspond to the person's knowledge base at the time of the encoding. And not one that's consistent with your current world view.
A lot of people argue, oh, well, you're just remembering something and putting it into adult language. Well, that's exactly my point. So which part of it is the real memory, and which part of it is the adult reconstruction of what must have happened?
So for example, the concept of disgust, as I mentioned earlier, doesn't really emerge until about five years of age. So if you're talking when you're three that you felt disgusted when this thing happened, that's not a child emotion that you're actually remembering.
So there is solid empirical evidence that the concepts and words used to retrieve true early memories are age appropriate to the memories themselves. So if I give you a word that wasn't in your vocabulary when you're a particular age, you're not going to be able to recall a memory of that type from that age, because you didn't have it in your vocabulary at the time. Or so goes the argument. And I'm sure the debate is still raging, but this is a paper that's just been published by Wells et al. in Quarterly Journal of Experimental Psychology, where they did tests of this sort of stuff.
So when we see age inappropriate material, you've got it in these types of dialogues, you have to wonder, where did that come from. Right, more curious concepts. Of course, often the events we recall from childhood are devoid of emotion and are neither stressful or traumatic. Some famous studies on this show that what you recall from early childhood are things like, I remember sitting in the kitchen watching my mother do the dishes. That's it. That's my memory. I have no context for it. I don't know why I remember it. It's just there. And it's not any particular emotion.
So in fact, stressful and traumatic events are not always remembered more accurately than more benign events, such as sitting there watching your mother wash the dishes in the kitchen. However, many of the transcripts that make their way to the courtroom contain emotional, I remember feeling introspective. I remember thinking temporal the exact sequence of events, which, depending on the age of the children don't yet, and verbatim exact conversations information.
These things are rarely seen. And I mean, there's lots of research on this, but some of this stuff comes out of Harlene Haynes' lab in Otago, that these things are rarely seen in children's actual memories of recently experienced events. Even when they're directly questioned about those properties of the event, they do not recall them. So they just don't have that in the age of five to six range, whereas older children, 9 to 10-year-olds, certainly do have that information.
So clearly adult narratives about events that contain such information are not just memories, but they've been influenced, like all autobiographical memories tend to be, by the narrator's current needs-- IE, I get compensation-- wishes, intentions, and their world view as an adult.
So what are the courtroom implications? Well, there are many more examples of these disconnects between memory facts and memory myths. And then there's a book in this somewhere, I think, but the common sense view of memory and the scientific truths of memory are still at a huge disconnect. And we have to resolve this somehow.
So when it comes to evaluating cases in which the main or only evidence consists of adults' memories of childhood events, caution needs to be exercised, not only concerning what those memories should contain, age appropriate concepts and meanings, but also the lengthy interval over which those memories have been retained, allegedly.
Now, we'll talk a little bit about some of these effects, including forgetting, interference, and reconsolidation effects. I'll get a little neurosciencey in a minute, for all of those who like neurosciencey things.
So we have a real problem here. And it's a matter of how do we address it in a courtroom? So what should triers of fact know? Well, triers of fact, of course, should know that cognitive, for example, knowledge base and neurobiological, for example, consolidation or reconsolidation, changes during development, effect how information is encoded originally, stored, subsequently retrieved, and they constrain the content and durability of childhood memory.
Nobody, very few jurors would know that. And no judge that I've ever run into, bar one, knew that. Memories can change while in storage due to processes associated with forgetting, interference, and reconsolidation. And memories can be regularly retrieved, or reinstated, or reactivated. And that can change the memory, unbeknownst to the rememberer.
And peripheral information, again, is not well preserved in childhood recollections. And those recollections tend to be sparse, fragmented, and containing information, mostly about core features and age appropriate meaning.
So let me elaborate a little bit on this. I should note, just to give you a really good example of a fragmented memory that could be an abuse memory, I remember-- I remember-- I was giving a lecture to-- a lecture. I was giving a talk to women's group many, many years ago. And I was talking about false memories and so on and so forth.
And one woman, I started getting into trouble, because one woman said to me, "what do you think? We're idiots? We actually develop a false memory of being abused as a child, when in fact we weren't? You must be only talking about women who aren't empowered."
So I started to get up and back out of the room, and I thought this wasn't going to be good. But a woman in the back stood up, and she said, "I know exactly what he's talking about." She said, "if I needed a false memory of something that happened to me, I've got one. And it's based on something that really happened."
Her memory was a fragment, a decontextualized fragment, herself lying in a crib, head down, bum up. She was naked, and the room was hot. And there was a shadowy figure behind her. That's her fragment.
She said, "now if I needed to believe that I had been abused, this was the one I would've picked." So she asked her mother. She said, "was there ever an experience like this that I would have been through?" She said, "yeah, you had pneumonia. And you had a very high temperature, high fever. We had to keep the room hot, and we had to come in." And if she'd remember this part, it would have been even better for her abuse scenario. They had to take her temperature rectally to make sure it was going down.
So that's a fragment, and it was very powerful. This has always stuck with me, because if you wanted to create a false memory, if you wanted to take that kernel of something that she remembered and turn it into something based on her own current needs, wishes, aspirations, and worldview, she could have done that very easily.
And that's the power of some of these false memories, that you have something that may be a real kernel, but then the weaving starts. And then nobody can tell what the difference is between one and the other.
OK, so a little bit about memory development. So declarative, explicit memory, memory of facts and experiences. When experiences are encoded with respect to the self, we call them autobiographical. So they're no longer just events that happened. They are events that happened to me.
It's this form of declarative memory that we're dealing with in the courtroom. So autobiographical memory or adults remembering events that they experienced as a child, to me.
So let's take a look at early autobiographical memory, and first we'll look at some behavioral evidence about what goes on. And then I'll do a little bit of neurobiological evidence to show that there's some support both ways.
So most if not all memories from early childhood, that would be at the most conservative from 18 to 24 months and earlier, are effectively lost or certainly not available to conscious recall later on. And this is known as infantile amnesia.
Research in humans and non-human animals alike has shown that forgetting occurs more rapidly in younger members of the species. So this might be one of the sources of infantile amnesia, and I'll talk a little bit about that in a second.
Because the increased sensitivity of early memories to forgetting extends also into the preschool years, it's not surprising that studies with adults will show that very few events are remembered from early childhood, and certainly not before-- very few before the ages of five to seven are reliably recalled, certainly not recalled in the same way that we expect adults to be able to recall events that happen in adulthood.
And that is known as childhood amnesia. So a little bit older. Infantile is before age two. From two to five or so is what's been termed childhood amnesia. So this is the old standby graph from Dave Rubin's work that shows that this is across numerous studies all about what adults can recall of their early childhood.
So this is the age at which the memory was formed. And this is the proportion of memories per year in that area. So this a composite. I think it was about five or 11,000 childhood memories. Should read my own slides one day.
So as you can see, before about the age of five or so, there are very few, really very few memories. You could even argue up until about five. Some will argue, as the British Psychological Society report on memory in the law as argued, that memories before about the age of nine or 10 should not be considered to be reliable in a courtroom without corroborating evidence of some sort.
That may be a little on the strict side. And of course, it will depend on the individual. But there is very good evidence anyways, that for what we can remember from our childhoods as an adult, that it's not very good up until about this age here.
So when we get memories in the courtroom that are from here, you've got to wonder how did those memories suddenly get preserved, especially if we have lots of evidence that emotional, the emotionality of the memory doesn't necessarily count, either, that that's not an important feature of recall of early childhood events.
So we can look at sparser encoding. So children's narrative recall of a recent event is sparser. That is, typically it contains fewer peripheral details about the experience than older children's recall of the same event. That's just a fact that's been replicated billions of times in billions of studies.
So that suggests that fewer details are stored in the first place in younger children's memory. So the encoding is impoverished or is sparser, anyways. So accordingly, although younger children are frequently correct in the basic facts of what happened, for example, we went on a trip to a museum, their narratives do not contain any additional information that older children's narratives would be. "It was a warm and sunny day. I was wearing my favorite dress. We learned what a curator was and so on."
So there's another. So younger children's memories are more sparsely encoded than older children's memory. And more sparsely encoded information oftentimes isn't remembered as well as more densely encoded information. So again, sparser encoding might be one of the sources of infantile and childhood amnesias.
Changes in knowledge base. So there are several changes that happen in the knowledge base. They change both in terms of the concepts, the content. We acquire concepts as we get older. We learn new things. But as we learn new things, we also change the organization of that knowledge space.
Which can have an impact as to whether the better organized information is in memory, typically the better remembered it is. So somebody named CC et all in--
AUDIENCE: I can't believe anything that guy's published.
MARK L HOWE: I know, I know. Well, I've seen some things in Retraction Watch about him. So this is-- darn it all. I love this study. I think this is one of the best studies in this topic, in this area, that children were asked to make similarity judgments among concepts or objects, and using fancy statistical multi-dimensional scaling techniques, what you can do is, you can calculate relational differences between concepts and you can map how the relationships between concepts changes with age.
Simple in thinking in a way, and very complicated in execution. So when this particular study looked at four and nine year olds, rated the same set of concepts for similarity, different scaling solutions were obtained, indicating that, of course, older children's knowledge base was differently organized than younger children's knowledge base, even for the same concepts.
So now if you throw in that there are different concepts as you get older, too, then all of that changes, too. So these differences have, of course, important consequences for understanding what children can have available to them when they're encoding and storing experiences at different ages. Of course, again, it's not just the accrual of concepts, but it's the way in which it reorganizes the entire knowledge base that's important. So triers of fact need to know about that.
Faster forgetting. Well, I mentioned this already, but it is the case that episodic components of a memory, for example, the who, what, where, and when, usually deteriorate more rapidly than the meaning or core components of the experience. Depending, the who might be important in these particular cases, but other peripheral details will disappear more quickly. The source of it will disappear.
So this means that although the central features of the experience, again, "I went to a museum when I was young," are preserved in memory for later, additional peripheral details, what time of day it was when I visited, who I was with, what I was wearing, are not going to be retained in memory. And that's especially true the younger the child.
So it is the waning of these episodic details that really undermines the integrity and longevity of early memory traces, and often lead the adult rememberer with only vague and, again, decontextualized, because you don't know the meaning of the experience, because you don't have those meaning concepts at the time the experience occurred.
So that we see these very detailed representations with lots of meaning about the experience in these transcripts is inconsistent with what we know about early memories. And of course, I couldn't resist. We have to throw in the emergence of the self, my favorite pet theory about this. And the fourth phenomenon is that poor recollection of childhood memories--
And this, I will say this, that this only pertains to human animals, although there are some non-human species that also have mirror self-recognition and do recognize the self. That's another discussion over a beer or something.
But that these childhood memories become better integrated and more stable in a number of cognitive changes that happen, including the acquisition of superconcepts. But one of the first superconcepts to emerge is the emergence of the cognitive self. And it's then that these memories are no longer memories of an event that just happened. They are now memories of events that happened to a "me."
And now they become important because they define me. And me defines how I then interpret subsequent experiences and encode those experiences, too. So it provides perhaps, the ego or the self, provides the most important ways in which we structure our memories and keep them to ourselves.
Now, there are other developments, of course. I'm not head in the sand. There are other developments in language, including pronoun use and the use of sharing experiences with others, typically parents, that contribute to restructuring and increased retention of information of early childhood experiences.
So there are a number of different changes that occur from early childhood through to later childhood that make memories and autobiographical remembering more stable, better integrated information, and retain for longer and longer periods of time as children get older.
So again, the idea would be you, need to be a little bit skeptical if you have highly detailed memories from childhood that adults claiming to remember, because those things don't even exist in childhood itself.
So I forgot to bring my slide, my favorite neuro slide, which is a hippo on campus. But anyways, I did. I did that one at the last ICON, I think. The Japanese love it there.
Anyways, so these behavioral changes, of course, don't happen in isolation. And I'm not saying that they're caused by any neurobiological changes, to the chagrin of maybe a number of neurobiologists, including Chuck Nelson and others, but they are correlated with and potentially mediated by additional neurobiological changes in developmental.
So developmental neuroscientists have lots and lots of fun toys to play with now. And so there's a lot of information on brain structure, on brain function, and how changes through early childhood into adolescence, as all of you here would know.
In terms of structure, of course, one of the big things is the cortical thinning. Presuming you know there's this great, big, huge expansion of neural growth early, and then there's pruning of synapses as they're not used anymore, et cetera, et cetera.
And of course, this appears earliest in the sensory cortices rather than in the association cortices and the prefrontal cortex. Whereas white matter volume increases during development, mainly as a result of increases of axon diameter and myelination. Of course, these are critical for communication paths and also the speed of communication among neurons. Basic.
Additional findings suggest that there's both structural-- changes in structural and functional connectivity, which is important, particularly in the medial temporal lobe, where you find the hippo on campus and other structures, the dentate gyrus and so on. Important for consolidation.
And they're rapid, very rapid changes that happen in this area over the first postnatal year. But of course, these also continue into later years as well. But it's been argued that some of these very rapid changes in the first and second postnatal years are perhaps responsible for the neurobiological rationale for infantile amnesia. Well, there's another one coming up, too. Which I'll talk about in a second.
So these areas change over the first few years life, together changes in the dorsolateral PFC. And they're important because they serve to bind representations. So the better bound representation is, the more likely it is to be retained over longer periods of time. So binding is a critical feature here.
So these neurobiological findings are consistent with the behavioral data that I've talked about in terms of younger children having qualitatively and quantitatively different knowledge base with more limited and slower semantic processing. So they're not integrating the information as well in childhood. So if you have poorer integrated traces, you're less likely to be able to remember these events.
So again, basically these changes begin early in life and continue, as I say, through adolescence, both qualitative and quantitative in nature. And these changes in the encoding process, like increased binding, consolidation processes leading to greater longevity and retrieval processes, the development of strategic monitoring of behavioral data contribute to the increased ability to interpret the event that's occurring, as well as the ability to remember the experiences over longer and longer retention intervals.
So there is a nice neurological base that's consistent with all the behavioral data that shows a nice pattern. It's funny, judges and jurors don't know about this.
Now my favorite topic, reconsolidation. We're going to be embarking with some colleagues in the Netherlands. It's the only place, apparently, this research can be conducted, with the IRBs that we have in other countries, where we're going to start erasing memories. So and reconsolidation is your way forward. There's been a little bit of work currently in Manchester University in the UK that's shown erasing recent episodic memories using ECT.
So of course, it's not just the changes in memory development are important, but it's also what happens over this long retention interval, 20, 30, 40 years. What could potentially happen? And especially when these events are either re-experienced or rethought about, either through conversation or reminiscing or whatever.
So the contents of our current experiences can blend with what has been reactivated in memory. So what we're currently doing now can blend with the memory of what had happened before. And these altered contents get reconsolidated in memory.
So the attempts by many to forestall forgetting by rehearsing events and rehearsing what happened can actually have detrimental effects, because it can also cause the original memory trace to be altered and changed in potentially important ways.
So reconsolidation is one process that allows-- it's a good process, because it allows memory to be updated. And that may be another one of the reasons why we don't remember early childhood experiences, because they're no longer relevant in a sense, and they've been updated by more current experiences and blended with those.
So when memory traces are reactivated during the retrieval, they reenter this labile state, and they have to stabilize again if they're going to persist. In fact, reconsolidation is as important as consolidation is.
So it's during reconsolidatoin that when the memories are updated with new information, they can either be strengthened, they can be weakened, they can change, or they can actually be erased, so they no longer exist in storage.
Now, the critical thing for the courts to understand-- you understand all this sort of stuff, but the critical thing is, because we don't consciously register these reconsolidation processes, memories can be distorted or eliminated without our awareness. So we don't even know what's going on, in that sense.
Effects of stress and trauma. Systems that mediate stress, of course, again the hippo on campus and the amygdala-- haven't figured out what that is yet, to make a funny number-- undergo key changes in childhood and adulthood like everything else does.
But there are some important effects of prolonged stress, for example, child maltreatment, on a developing brain that can involve alterations in neural structures that underpin memory, including the hippocampus, the amygdala, and the medial PFC. One consequence of very long stress through maltreatment is poor consolidation of emotional information, just the opposite of what you would want.
You'd say, well, maltreated children, shouldn't they remember the horrible things that happened, given all the emotional stress and duress? Well, no, not always, in fact. So it can inhibit the consolidation of emotional information. And that occurs because under high levels of stress that inhibits neurogenesis. Neurogenesis is something important to forming new memories.
So althought he role of adult neurogenesis in memory consolidation in humans is hotly debated, because it's very hard to investigate it directly in humans, or something again an IRB issue. We'll get around that somewhere.
There is evidence that adult humans, that new neurons are added each day to the hippocampus at a rate commensurate with that found in non-human animals. So there is good nonhuman animal data that suggests that this stuff happens, and it's at quite a high rate. And that's good, presumably, for encoding new memories.
There's a recent paper by [? Acres ?] et al. at the University Toronto that's looked at neurogenesis in early life, and they've suggested that neurogenesis actually prevents memory longevity early in childhood. But its subsequent waning. So there's a lot of neurogenesis very early in life around the infantile amnesia period. And then all of a sudden, it starts to taper.
And so a lot of neurogenesis, it's like the Three Bears thing. The hot and the cold. So a lot of neurogenesis is bad for you. Some neurogenesis is good for you. So this is the idea that its subsequent waning to normal levels in adulthood can actually improve memory by reducing interference between overlapping memories that are formed at different points in time.
So you get almost like a-- not a time marker, but it's distinguished in terms of its temporalness. So regardless of differences in proliferation of neurogenesis with age, there is evidence that inhibition of neurogenesis leads to poorer storage and hence retention of stressful memories in non-human animals.
So overall, then, as we know from other research that an experience was stressful or traumatic is not a good predictor of a child's or even an adult's subsequent retention or recollection of that event.
And of course, people believe in the courts that if it was a traumatic event, of course you're going to remember it. How could you possibly forget? And there were many instances of actual traumatic experiences, like that where children do and adults do remember their childhood experiences.
So I hope, as is somewhat obvious from this talk, that the facts revealed by scientific study of memory and its both neurobiological and behavioral levels that what we know as a science is considerably different from what people who are accused of committing childhood sexual abuse will be confronted with by their triers of fact, and that in many, many cases, it's quite the opposite to these facts.
So it's important in this case that-- in all of these cases, particularly in historic child sex abuse cases, that the jurors or triers of fact be alerted to these facts before they adjudicate the memory evidence. Otherwise, they're not going to be able to interpret, I would argue, appropriately.
So legal policy procedures of practice should include a consideration of memory experts' evidence, unlike the judicial remarks we heard earlier in this talk, where "no, we don't need expert evidence et al. Sorry, we don't want you." And this should be given proper weight when deciding the guilt or innocence of the defendant.
Now, their reputation's already destroyed anyways, because it's already gone public. But at least they don't have to do jail time if it's not.
So let's end the talk on an optimistic note. I got a lot of time till? Right, so I'll whiz through it. I have this really long thing, but I'll cut it. So there has been some progress, and this is an example, and the one and only example that all of my lawyer friends and people who know this stuff have been able to find. And it was a Royal Courts of Justice Queen's Bench Division in which the judge in the case stated in his decision the following.
"An obvious difficulty which affects allegations in oral evidence based on recollection of events which occurred several years ago is the unreliability of human memory." Get him. He continued, "while everyone knows that memory is fallible, I do not believe that the legal system has sufficiently absorbed the lessons of a century of psychological research into the nature of memory and the unreliability of eyewitness testimony. One of the most important lessons of such research is that, in everyday life, we are not aware of the extent to which our own and other people's memories are unreliable, and believe our memories to be more faithful than they are.
Two common or related errors are dispose one, that the stronger, more vivid is our feeling or experience of recollection, the more likely the recollection is to be accurate, and two, that the more confident another person is in their recollection, the more likely the recollection is to be accurate."
I wrote this decision. No, I didn't. But just it's amazing. And I just found this before. This lawyer friend sent this to me just before it came out. I won't go through all of it, but I'll just go through a little bit more. "Underlying both of these errors is a faulty model of memory as a mental record which is fixed at the time of experience of an event and then fades more or less slowly over time.
In fact, psychological research has demonstrated that memories are fluid and malleable, being constantly rewritten whenever they are retrieved." Can we clone this guy? "This is true for even so-called flashbulb memories, that is, memories of experiencing or learning a particular shocking traumatic event. External information can intrude into the witness's memory, as can his or her own thoughts and beliefs, and so on and so forth.
Memory is especially unreliable when it recalls past beliefs, and the process of litigation itself subjects the memories of witnesses to powerful biases." This is point 19. "The nature of litigation is such that witnesses often have a stake in a particular version of events. This is obvious when a witness is party to or has a tie of loyalty to a party to the proceedings.
Other more subtle influences include allegiances created by the process of preparing a witness statement, and of coming to court to give evidence for one side in the dispute. The desire to assist or at least not prejudice the party who has called the witness or the party's lawyers, as well as a natural desire to give a good impression in public forum, can be significant motivating forces."
So he's obviously aware of the fallibility memory, but also of the things that affect people who are giving evidence at the time. You'll have a copy of this, so I won't read it all. But you can see that there is one person who seems to be particularly enlightened.
This is an important point. So he does say, "it is not uncommon in the present case, there's no exception for witnesses to be asked in cross-examination if they understand the difference between recollection and reconstruction, or whether their evidence is a genuine recollection or a reconstruction of events. Such questions are misguided in at least two ways.
First, they erroneously presuppose that there is a clear distinction between recollection and reconstruction, when all remembering of distant events involves reconstructive processes. Second, such questions disregard the fact that such processes are largely unconscious, and that the strength, vividness, and apparent authenticity of memories is not a reliable measure of their truth."
Restored my faith in the legal system again. But this is one character out of how many characters who are doing this and instruct juries or exclude memory experts from court? There is more. Case comment.
Now, it's interesting to note that this is a commercial case. This is not a historical child sex abuse case, and not one involving events remembered by adults in childhood. The memories being discussed in this case were only a few years old. It was Corporation A versus Corporation B in a commercial lawsuit. So what these were about were discussions that people were trying to remember board meetings and what was discussed during a board meeting, when there was no record of what had happened.
In the comments made by this judge-- of course soapbox again-- need to resound in criminal cases and other cases around the world right now. I mean, this guy is obviously very enlightened, and this guy should be one of the guys who gives a talk at one of these conferences, two judges and two barristers to tell people that yeah, it can happen.
Last two things, two other developments that have been relatively positive, and we're actually doing some research on these now to see whether they actually work or not. But there's been two recent changes in jury charges that judges can give at the end of a trial. The first one is a decision in New Jersey, which you probably heard of. Involved a defendant named Larry Henderson, who was accused of participating in a New Year's Day shooting.
Following a delay of approximately two weeks, a surviving witness identified Henderson from photos, and Henderson was convicted. It turned out, of course, that the initial identification of Henderson occurred after the investigating officers engaged in persuasive behavior. Worse, earlier in the day, the witness had consumed large amounts of wine, champagne, and crack cocaine. Unbeknownst to the officer, I'm sure, making the identification even more suspect.
So when Henderson appealed his conviction, and that's the citation there, the decision received national attention. And in essence, the ruling showed a sophisticated appreciation of problems with eyewitness memory and eyewitness identification and line-up stuff. And the decision led to changes in how evidence adduced through suggestive influences is treated in the courtroom.
Specifically, if a judge decides to admit such testimony in trial, for whatever reason, then jurors must be provided with instructions that will guide them on how to interpret this eyewitness evidence. IE, goes to the fallibility of memory and so on and so forth. I mean, if you want copies, I'm leaving copies of this presentation. But if you want to look at a particular citation and so on, it's right there.
So that's a way forward. The problem with it is, to some extent, is that it depends when the judge issues the instruction, I think. I said we're conducting research on this. A judge usually gives his instruction with the rest of his jury or her jury charge. But that's after all the bad evidence has been presented and the person's already formed a script or schema as to what's happened in the event.
So it's kind of hard to break that when it comes to the jury room. So maybe these things need to be done at the beginning, when the judge gives his initial or her initial charge to the jury about what they're to do during the trial, and say that you will be hearing some evidence that is of this sort, and you need to be cautious with respect to.
Jury instructions, too, you always have to end on Beth. I don't know why, but you just do. So inspired by this New Jersey decision, Beth took a year off and worked with some people who were lawyers, judges, and a person who can write normal English, instead of scientific English. And what they came up with is, they drafted a set of jury instructions that consider the problems with memory testimony much further. In essence, the instructions detail the fallibility of memory more generally and covers many of the topics that I've just talked about in this talk.
And now this is being used in Pennsylvania as judges charge to juries in Pennsylvania, when memory serves as evidence or as the only evidence. There's just been, hot off the press-- it's not even in the press. It's the Arizona Law Journal or whatever it is-- a study conducted in Arizona that had looked at these instructions to see whether they were effective or not.
I'm not going to report too much about it, because the study wasn't that well constructed in the first place. And the answer was, no, it just made all jurors who received the instruction more conservative, and they disregarded all memory evidence, which isn't the point, either.
But follow-up studies and some of the work we're going to be conducting hopefully will test some of these things as well and see where it does work and how well it works. I promise the end. What these advances show, I think, is that the implications for the shortcomings of memory, how children remember things in the first place, the types of things that can intervene over the long haul, reconsolidation and so on, and educating people about beliefs, changing their beliefs about memory to be more accurate to the scientific data will be a great help.
Once we align these two, we'll be able to advance our understanding of the development and capability of memory, but also support practitioners to develop new techniques and protocols for examining memory in forensic fields.
The ideal, of course, would be to have people who have a leg in both camps, people who are involved directly in the legal or forensic arena and who also are scientists. So what we have, then, is like what we hoped our clinicians would be. That is, scientist practitioners. Maybe we can hope for the same thing in the legal field, where we have scientist practitioner models for a legal process.
So the bad news of the talk is that there's still a substantial gap between what we know and what common sense beliefs are. We need to educate judges as well to allow memory expert testimony into the courts. And the hope is that the relationship between the scientific community and other professions continues to develop, so that what becomes known about memory might become better disseminated to influence policy changes, procedures, and practices in important forensic contexts, and people like us can get back to the lab bench and we don't have to go to the courtroom anymore.
And that's all I have to say. Thank you.
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Mark Howe, professor of psychology at City University London, discusses the nature of childhood memory and the reliability of memory evidence.
The talk, recorded September 12, 2014, is part of the Human Development Outreach and Extension Program.