Posts tagged autobiographical memory
Articles and news from the latest research reports.
For the first time, neuroscientists were able to find out how different thoughts are reflected in neuronal activity during natural conversations. Johanna Derix, Olga Iljina and the interdisciplinary team of Dr. Tonio Ball from the Cluster of Excellence BrainLinks-BrainTools at the University of Freiburg and the Epilepsy Center of the University Medical Center Freiburg (Freiburg, Germany) report on the link between speech, thoughts and brain responses in a special issue of Frontiers in Human Neuroscience.
"Thoughts are difficult to investigate, as one cannot observe in a direct manner what the person is thinking about. Language, however, reflects the underlying mental processes, so we can perform linguistic analyses of the subjects’ speech and use such information as a "bridge" between the neuronal processes and the subject’s thoughts," explains neuroscientist Johanna Derix.
The novelty of the authors’ approach is that the participants were not instructed to think and talk about a given topic in an experimental setting. Instead, the researchers analysed everyday conversations and the underlying brain activity, which was recorded directly from the cortical surface. This study was possible owing to the help of epilepsy patients in whom recordings of neural activity had to be obtained over several days for the purpose of pre-neurosurgical diagnostics.
For a start, borders between individual thoughts in continuous conversations had to be identified. Earlier psycholinguistic research indicates that a simple sentence is a suitable unit to contain a single thought, so the researchers opted for linguistic segmentation into simple sentences. The resulting “idea” units were classified into different categories. These included, for example, whether or not a sentence expressed memory- or self-related content. Then, the researchers analysed content-specific neural responses and observed clearly visible patterns of brain activity.
Thus, the neuroscientists from Freiburg have demonstrated the feasibility of their innovative approach to investigate, via speech, how the human brain processes thoughts during real-life conditions.
New Study Suggests a Better Way to Deal with Bad Memories
What’s one of your worst memories? How did it make you feel? According to psychologists, remembering the emotions felt during a negative personal experience, such as how sad you were or how embarrassed you felt, can lead to emotional distress, especially when you can’t stop thinking about it.
(Image: iStockphoto)
When these negative memories creep up, thinking about the context of the memories, rather than how you felt, is a relatively easy and effective way to alleviate the negative effects of these memories, a new study suggests.
Researchers at the Beckman Institute at the University of Illinois, led by psychology professor Florin Dolcos of the Cognitive Neuroscience Group, studied the behavioral and neural mechanisms of focusing away from emotion during recollection of personal emotional memories, and found that thinking about the contextual elements of the memories significantly reduced their emotional impact.
“Sometimes we dwell on how sad, embarrassed, or hurt we felt during an event, and that makes us feel worse and worse. This is what happens in clinical depression—ruminating on the negative aspects of a memory,” Dolcos said. “But we found that instead of thinking about your emotions during a negative memory, looking away from the worst emotions and thinking about the context, like a friend who was there, what the weather was like, or anything else non-emotional that was part of the memory, will rather effortlessly take your mind away from the unwanted emotions associated with that memory. Once you immerse yourself in other details, your mind will wander to something else entirely, and you won’t be focused on the negative emotions as much.”
This simple strategy, the study suggests, is a promising alternative to other emotion-regulation strategies, like suppression or reappraisal.
“Suppression is bottling up your emotions, trying to put them away in a box. This is a strategy that can be effective in the short term, but in the long run, it increases anxiety and depression,” explains Sanda Dolcos, co-author on the study and postdoctoral research associate at the Beckman Institute and in the Department of Psychology.
“Another otherwise effective emotion regulation strategy, reappraisal, or looking at the situation differently to see the glass half full, can be cognitively demanding. The strategy of focusing on non-emotional contextual details of a memory, on the other hand, is as simple as shifting the focus in the mental movie of your memories and then letting your mind wander.”
Not only does this strategy allow for effective short-term emotion regulation, but it has the possibility of lessening the severity of a negative memory with prolonged use.
In the study, participants were asked to share their most emotional negative and positive memories, such as the birth of a child, winning an award, or failing an exam, explained Sanda Dolcos. Several weeks later participants were given cues that would trigger their memories while their brains were being scanned using magnetic resonance imaging (MRI). Before each memory cue, the participants were asked to remember each event by focusing on either the emotion surrounding the event or the context. For example, if the cue triggered a memory of a close friend’s funeral, thinking about the emotional context could consist of remembering your grief during the event. If you were asked to remember contextual elements, you might instead remember what outfit you wore or what you ate that day.
“Neurologically, we wanted to know what happened in the brain when people were using this simple emotion-regulation strategy to deal with negative memories or enhance the impact of positive memories,” explained Ekaterina Denkova, first author of the report. “One thing we found is that when participants were focused on the context of the event, brain regions involved in basic emotion processing were working together with emotion control regions in order to, in the end, reduce the emotional impact of these memories.”
Using this strategy promotes healthy functioning not only by reducing the negative impact of remembering unwanted memories, but also by increasing the positive impact of cherished memories, Florin Dolcos said.
In the future, the researchers hope to determine if this strategy is effective in lessening the severity of negative memories over the long term. They also hope to work with clinically depressed or anxious participants to see if this strategy is effective in alleviating these psychiatric conditions.
These results were published in Social Cognitive and Affective Neuroscience.
(Source: beckman.illinois.edu)
Kids’ earliest memories might be earlier than they think
The very earliest childhood memories might begin even earlier than anyone realized – including the rememberer, his or her parents and memory researchers.
Four- to 13-year-olds in upstate New York and Newfoundland, Canada, probed their memories when researchers asked: “You know, some kids can remember things that happened to them when they were very little. What is the first thing you can remember? How old were you at that time?” The researchers then returned a year or two later to ask again about earliest memories – and at what age the children were when the events occurred.
“The age estimates of earliest childhood memories are not as accurate as what has been generally assumed,” report Qi Wang of Cornell University and Carole Peterson of Memorial University of Newfoundland in the March 2014 online issue of Developmental Psychology. “Using children’s own age estimates as the reference, we found that memory dating shifted to later ages as time elapsed.”
Childhood amnesia refers to our inability to remember events from our first years of life. Until now, cognitive psychologists estimated the so-called childhood amnesia offset at 3.5 years – the average age of our very earliest memory, the authors noted in their report, “Your Earliest Memory May Be Earlier Than You Think: Prospective Studies of Children’s Dating of Earliest Childhood Memories.”
But the children who originally answered, for example, “I think I was 3 years old when my dog fell through the ice,” postdated that same earliest memory by as much as nine months when asked – in follow-up interviews a year or two years later – to recall again. In other words, as time went by, children thought the same memory event occurred at an older age than they had thought previously. And that finding prompts Wang and Peterson to question the 3.5-year offset for childhood amnesia.
“This can happen to adults’ earliest childhood memories, too,” says Wang, professor of human development and director of the Social Cognition Development Laboratory in Cornell’s College of Human Ecology. “We all remember some events from our childhood. When we try to reconstruct the time of these events, we may postdate them to be more recent than they actually were, as if we are looking at the events through a telescope. Although none of us can recall events on the day of our birth – childhood amnesia may end somewhat earlier than the generally accepted 3.5 years.”
Parents might help because they have more clues (e.g., where they lived, what their children looked like at the time of events) to put their children’s experiences along a timeline. When asked, for example, “How old was Evan when Poochie fell through the ice?” they erred less than Evan had. Still, they are not free from errors in their time estimates.
The only way to settle that, Wang and Peterson mused, would be to look for documented evidence – a parent’s diary, for instance, or a newspaper account of Poochie’s memorable rescue.
Music brings memories back to the brain injured
In the first study of its kind, two researchers have used popular music to help severely brain-injured patients recall personal memories. Amee Baird and Séverine Samson outline the results and conclusions of their pioneering research in the recent issue of the journal Neuropsychological Rehabilitation.
Although their study covered a small number of cases, it’s the very first to examine ‘music-evoked autobiographical memories’ (MEAMs) in patients with acquired brain injuries (ABIs), rather than those who are healthy or suffer from Alzheimer’s Disease.
In their study, Baird and Samson played extracts from ‘Billboard Hot 100’ number-one songs in random order to five patients. The songs, taken from the whole of the patient’s lifespan from age five, were also played to five control subjects with no brain injury. All were asked to record how familiar they were with a given song, whether they liked it, and what memories it invoked.
Doctors Baird and Samson found that the frequency of recorded MEAMs was similar for patients (38%–71%) and controls (48%–71%). Only one of the four ABI patients recorded no MEAMs. In fact, the highest number of MEAMs in the whole group was recorded by one of the ABI patients. In all those studied, the majority of MEAMs were of a person, people or a life period and were typically positive. Songs that evoked a memory were noted as more familiar and more liked than those that did not.
As a potential tool for helping patients regain their memories, Baird and Samson conclude that: “Music was more efficient at evoking autobiographical memories than verbal prompts of the Autobiographical Memory Interview (AMI) across each life period, with a higher percentage of MEAMs for each life period compared with AMI scores.”
“The findings suggest that music is an effective stimulus for eliciting autobiographical memories and may be beneficial in the rehabilitation of autobiographical amnesia, but only in patients without a fundamental deficit in autobiographical recall memory and intact pitch perception.”
The authors hope that their ground-breaking work will encourage others to carry out further studies on MEAMs in larger ABI populations. They also call for further studies of both healthy people and those with other neurological conditions to learn more about the clear relationship between memory, music and emotion; they hope that one day we might truly “understand the mechanisms underlying the unique memory enhancing effect of music”.
People with highly superior powers of recall also vulnerable to false memories
People who can accurately remember details of their daily lives going back decades are as susceptible as everyone else to forming fake memories, UC Irvine psychologists and neurobiologists have found.
In a series of tests to determine how false information can manipulate memory formation, the researchers discovered that subjects with highly superior autobiographical memory logged scores similar to those of a control group of subjects with average memory.
“Finding susceptibility to false memories even in people with very strong memory could be important for dissemination to people who are not memory experts. For example, it could help communicate how widespread our basic susceptibility to memory distortions is,” said Lawrence Patihis, a graduate student in psychology & social behavior at UC Irvine. “This dissemination could help prevent false memories in the legal and clinical psychology fields, where contamination of memory has had particularly important consequences in the past.”
Patihis works in the research group of world-renowned psychologist Elizabeth Loftus, who pioneered the study of false memories and their implications.
Persons with highly superior autobiographical memory (HSAM, also known as hyperthymesia) – which was first identified in 2006 by scientists at UC Irvine’s Center for the Neurobiology of Learning & Memory – have the astounding ability to remember even trivial details from their distant past. This includes recalling daily activities of their life since mid-childhood with almost 100 percent accuracy.
The lead researcher on the study, Patihis believes it’s the first effort to test malleable reconstructive memory in HSAM individuals.
Working with neurobiology & behavior graduate student Aurora LePort, Patihis asked 20 people with superior memory and 38 people with average memory to do word association exercises, recall details of photographs depicting a crime, and discuss their recollections of video footage of the United Flight 93 crash on 9/11. (Such footage does not exist.) These tasks incorporated misinformation in an attempt to manipulate what the subjects thought they had remembered.
“While they really do have super-autobiographical memory, it can be as malleable as anybody else’s, depending on whether misinformation was introduced and how it was processed,” Patihis said. “It’s a fascinating paradox. In the absence of misinformation, they have what appears to be almost perfect, detailed autobiographical memory, but they are vulnerable to distortions, as anyone else is.”
He noted that there are still many mysteries about people with highly superior autobiographical memory that need further investigation. LePort, for instance, is studying forgetting curves (which involve how many autobiographical details people can remember from one day ago, one week ago, one month ago, etc., and how the number of details decreases over time) in both HSAM and control participants and will employ functional MRI to better understand the phenomenon.
“What I love about the study is how it communicates something that memory distortion researchers have suspected for some time: that perhaps no one is immune to memory distortion,” Patihis said. “It will probably make some nonexperts realize, finally, that if even memory prodigies are susceptible, then they probably are too. This teachable moment is almost as important as the scientific merit of the study. It could help educate people – including those who deal with memory evidence, such as clinical psychologists and legal professionals – about false memories.”
The study appears this week in the early online version of Proceedings of the National Academy of Sciences.
Reconstructing the Past: How Recalling Memories Alters Them
Recently the neurologist and author Oliver Sacks recalled a vivid childhood memory, recounted in his autobiography, Uncle Tungsten.
During WWII he lived in London during the Blitz, and on one occasion:
"…an incendiary bomb, a thermite bomb, fell behind our house and burned with a terrible, white-hot heat. My father had a stirrup pump, and my brothers carried pails of water to him, but water seemed useless against this infernal fire—indeed, made it burn even more furiously. There was a vicious hissing and sputtering when the water hit the white-hot metal, and meanwhile the bomb was melting its own casing and throwing blobs and jets of molten metal in all directions."
Except when his autobiography came out, one of his older brothers told him he’d misremembered the event. In fact both of them had been at school when the bomb struck so they could not have witnessed the explosion.
The ‘false’ memory, it turned out, was implanted by a letter. Their elder brother had written to them, describing the frightening event, and this had lodged in his mind. Over the years the letter had gone from a third-person report to a first-person ‘memory’.
Turning the memory over in his mind, Sacks writes that he still cannot see how the memory of the bomb exploding can be false. There is no difference between this memory and others he knows to be true; it felt like he was really there.
This sort of experience is probably much more common than we might like to imagine. Many memories which have the scent of authenticity may turn out to be misremembered, if not totally fictitious events, if only we could check. Without some other source with which to corroborate, it is hard verify the facts, especially for events that took place long ago.
That these sorts of distortions to memory happen is unquestioned, what fascinates is how it comes about. Does the long passage of time warp the memory, or is there some more active process that causes the change?
A study published recently sheds some light on this process and provides a model for how memories like Sack’s become distorted.
Shakespeare and Wordsworth boost the brain, new research reveals
Scientists, psychologists and English academics at Liverpool University have found that reading the works of the Bard and other classical writers has a beneficial effect on the mind, catches the reader’s attention and triggers moments of self-reflection.
Using scanners, they monitored the brain activity of volunteers as they read works by William Shakespeare, William Wordsworth, T.S Eliot and others.
They then “translated” the texts into more “straightforward”, modern language and again monitored the readers’ brains as they read the words.
Scans showed that the more “challenging” prose and poetry set off far more electrical activity in the brain than the more pedestrian versions.
Scientists were able to study the brain activity as it responded to each word and record how it “lit up” as the readers encountered unusual words, surprising phrases or difficult sentence structure.
This “lighting up” of the mind lasts longer than the initial electrical spark, shifting the brain to a higher gear, encouraging further reading.
The research also found that reading poetry, in particular, increases activity in the right hemisphere of the brain, an area concerned with “autobiographical memory”, helping the reader to reflect on and reappraise their own experiences in light of what they have read. The academics said this meant the classics were more useful than self-help books.
Philip Davis, an English professor who has worked on the study with the university’s magnetic resonance centre, will tell a conference this week: “Serious literature acts like a rocket-booster to the brain.
"The research shows the power of literature to shift mental pathways, to create new thoughts, shapes and connections in the young and the staid alike."
Memory vs. Math: Same brain areas show inverse responses to recall and arithmetic
Scientists have historically relied on neuroimaging – but not electrophysiological – data when studying the human default mode network (DMN), a group of brain regions with lower activity during externally-directed tasks and higher activity if tasks require internal focus. Recently, however, researchers at Stanford University School of Medicine recorded electrical activity directly from a core DMN component known as the posteromedial cortex (PMC) during both internally- and externally-directed waking states – specifically, autobiographical memory and arithmetic calculation, respectively. The data they recorded showed an inverse relationship – namely, the degree activation during memory retrieval predicted the degree of suppression during arithmetic calculation – which they say provides important anatomical and temporal details about DMN function at the neural population level.
They never forget: The strange gift of perfect memory
20 August 2012 by Kayt Sukel
Some people can recall what happened on almost every day of their lives. Unlocking their secrets could shed light on the way all our memories work
IT WAS an email that memory researcher James McGaugh found hard to believe. The sender, a 34-year-old housewife named Jill Price, was claiming that she could recall key events on any date back to when she was about 12, as well as what she herself had done each day.
"Some people call me the human calendar," she wrote, "while others run out of the room in fear. But the one reaction I get from everyone who finds out about this ‘gift’ is amazement. I run my entire life through my head every day and it drives me crazy!"
McGaugh invited Price to his lab, making sure he had to hand a copy of 20th Century Day by Day, a book that lists important events by date. He opened the book to random pages and asked Price what had happened on those days. “Whether it was a plane crash or some elections or a movie star doing an outrageous thing, she was dead on,” he recalls. “Time and time again.”
That was in June 2000. McGaugh’s group has worked closely with Price ever since, and has discovered she is one of a select few with similar abilities. These individuals are neither autistic savants nor masters of mnemonic-based tricks of recall, yet they can remember key events from almost every day of their lives. Learning more about their abilities and how their brains are wired should lead to insights into the nature of human memory.
Intrigued by McGaugh’s findings, I arranged to visit his lab at the University of California, Irvine, to find out how these people live with such unusual abilities - and what it is like for the researchers working with them. “It never ceases to amaze me,” says McGaugh’s colleague, Aurora LePort. “Some of them can remember every day you give them.” She says studying people whose powers of recall seem to be enhanced, rather than impaired, offers us a new tool to explore memory.
It is certainly fair to say that most of our knowledge of memory derives from looking at memory loss. The classic case is that of Henry Molaison (better known as “HM”), who had surgery nearly 60 years ago to treat severe epilepsy. In a misguided attempt to remove the source of the seizures, several parts of the brain were cut out, including both hippocampi, curled up ridges on either side of the brain.
For HM, the consequences were catastrophic. Although he could still recall his early life, he was no longer able to lay down memories of things that happened to him after the surgery. Every day, the researchers studying his condition had to introduce themselves anew. Intriguingly, though, he could perform tasks that used short-term memory, like retaining a phone number for a few minutes.
Thanks to HM and many other people with neurological problems caused by head injuries and strokes, we now know that there are different kinds of remembering. Our short-term memories last up to about a minute, unless they are reinforced, or “rehearsed” through further repetition. While much about the neuroscience of memory remains mysterious, our hippocampi seem to be involved in turning these fleeting impressions into long-term memories, which are thought to be stored in the temporal lobes on either side of the brain.
Long-term memories can be subdivided into semantic ones to do with concepts, such as the fact that London is the UK capital, and autobiographical memories, about everyday events that we experience. Price has no special abilities with regard to her short-term or semantic memory, but when it comes to autobiographical memory, her scores are off the chart.
Brains are different in people with highly superior autobiographical memory
July 30, 2012
UC Irvine scientists have discovered intriguing differences in the brains and mental processes of an extraordinary group of people who can effortlessly recall every moment of their lives since about age 10.
The phenomenon of highly superior autobiographical memory – first documented in 2006 by UCI neurobiologist James McGaugh and colleagues in a woman identified as “AJ” – has been profiled on CBS’s “60 Minutes” and in hundreds of other media outlets. But a new paper in the peer-reviewed journal Neurobiology of Learning & Memory’s July issue offers the first scientific findings about nearly a dozen people with this uncanny ability.
All had variations in nine structures of their brains compared to those of control subjects, including more robust white matter linking the middle and front parts. Most of the differences were in areas known to be linked to autobiographical memory, “so we’re getting a descriptive, coherent story of what’s going on,” said lead author Aurora LePort, a doctoral candidate at UCI’s Center for the Neurobiology of Learning & Memory.
Surprisingly, the people with stellar autobiographical memory did not score higher on routine laboratory memory tests or when asked to use rote memory aids. Yet when it came to public or private events that occurred after age 10½, “they were remarkably better at recalling the details of their lives,” said McGaugh, senior author on the new work.
"These are not memory experts across the board. They’re 180 degrees different from the usual memory champions who can memorize pi to a large degree or other long strings of numbers," LePort noted. "It makes the project that much more interesting; it really shows we are homing in on a specific form of memory."
She said interviewing the subjects was “baffling. You give them a date, and their response is immediate. The day of the week just comes out of their minds; they don’t even think about it. They can do this for so many dates, and they’re 99 percent accurate. It never gets old.”
The study also found statistically significant evidence of obsessive-compulsive tendencies among the group, but the authors do not yet know if or how this aids recollection. Many of the individuals have large, minutely catalogued collections of some sort, such as magazines, videos, shoes, stamps or postcards.
UCI researchers and staff have assessed more than 500 people who thought they might possess highly superior autobiographical memory and have confirmed 33 to date, including the 11 in the paper. Another 37 are strong candidates who will be further tested.
"The next step is that we want to understand the mechanisms behind the memory," LePort said. "Is it just the brain and the way its different structures are communicating? Maybe it’s genetic; maybe it’s molecular."
McGaugh added: “We’re Sherlock Holmeses here. We’re searching for clues in a very new area of research.”
Provided by University of California, Irvine
Source: medicalxpress.com