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Memory
Written and researched by Bob Murray, PhD
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Sheep Have Amazing Mental Powers!
November 10, 2001
I don't know why it is but the most reported item in the scientific literature this week concerns the mental abilities of sheep. Nature had the story, so did Scientific American, New Scientist and a number of other journals as well as the popular press. Perhaps since we've spent so much time counting sheep, we're surprised to discover that they can probably count us.
Anyway, according to British scientists sheep probably experience some degree of emotion and could even be capable of conscious thought. This astonishing verdict is based on the ability of sheep to remember old faces, be it a member of the flock or even a shepherd.
"The way the sheep's brain is organized suggests they must have some kind of emotional response to what they see in the world," Dr Keith Kendrick, of the Babraham Institute, Cambridge, told BBC News Online. "It does beg the question that sheep must potentially be able to think about individuals that are absent from their environment," he said.
New studies have revealed that sheep can remember up to 50 sheep faces as well as familiar human faces, such as their shepherd. They do this using a similar neural mechanism, and a similar part of the brain, to that of humans. Memories only start to fade after about two years of absence.
One inference is that sheep are capable of conscious thought at some level, says Dr Kendrick. "We [humans] are obviously capable of conscious perception of faces using this exact same system in the brain as is present in the sheep. Therefore, it would be surprising if they were not capable of some level of consciousness using that same system."
The Cambridge team made their discovery by presenting sheep with 25 pairs of similar faces. The animals were trained to associate each of the pair with a food reward, learning to recognise individual faces.
The scientists then measured activity in regions of the sheep's brain associated with visual recognition. As in humans, these reside in the temporal and frontal lobes of the brain, including a greater involvement of the right hemisphere. They found that sheep could remember 50 other sheep faces, even in profile.
The specialised face-processing system in the sheep brain offers advantages for long-term recognition of many individuals that are similar to those for humans, say the Babraham researchers.
"In humans, analogous brain regions and neural circuits are activated equivalently when we see or form mental images of the faces of specific individuals," they write in the journal Nature. "This suggests that sheep may be capable of using the same system to remember and respond emotionally to individuals in their absence."
The remarkable memory of sheep could extend to other farm animals. Goats, cattle and horses probably have a similar ability to recognise faces, says Dr Kendrick. But dogs and cat have poorer visual systems and may not be as well equipped.
The team says the work has implications for medicine, as well as animal husbandry. It could shed light on a rare human condition where people are unable to recognise faces.
More and more we are discovering how little really separates humankind from other animals and how really unspecial we are. Recent studies have shown that chimps feel compassion, bees have cognitive ability and chickens have consciousness. This ought to give pause to those who use animals in research experiments, dissect frogs in school biology classes or excuse animal cruelty. BM
Read more in BBC News
Read more in the Scientific American
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Link Unearthed Between Lefties In Family And Memory
October 26, 2001
Two recent experiments have tended to established the rather odd link between left-handedness and the ability to remember events. What's more, psychologists may finally be able to explain why kids don't remember events until they are about four years old.
This recent research is reported in the October issue of Neuropsychology, published by the American Psychological Association (APA). Stephen D Christman, PhD, and Ruth E Propper, PhD, of the University of Toledo in Ohio, studied memory as a function of family handedness. Interestingly, people don't have to be personally left-handed to share a unique trait: there is evidence that the two brain hemispheres of even right-handers with left-handed relatives share functions more equally, interact more and are connected by a larger corpus callosum (the bundle of mediating fibers) than the hemispheres of people with right-handed relatives. Although it is not well understood, there is a hereditary component to handedness.
Christman and Propper studied two types of memory -- episodic (the recall and recognition of events) and non-episodic (factual memory and implicit memory, the latter of which concerns things people "just know"). Left-handedness seems to go with a better performance in the former, episodic, memory.
Strength or weakness in either, says Christman, "may not have much effect in educational settings, as we can recall things we have learned by 'remembering' them (episodic memory) or by 'knowing' them (implicit memory). The main difference is that people who 'remember' can also recall details about the time and place at which they first learned this fact."
The researchers stress that memory performance has nothing to do with so-called "brain dominance."
"While the notion of people being right-brained or left-brained is common in the popular press," says Christman, "it has received very little support in the scientific literature. Both hemispheres of all people are going to be involved in virtually all tasks."
The findings also shed light on why children have no episodic memories until about age 4. The onset of episodic memory roughly coincides with the corpus callosum's maturation and myelinization, the growth of fatty protective sheaths around nerve fibres. In light of the findings, it would mean that a functional corpus callosum is critical in the formation of event memories and therefore explain why its maturation in early childhood is at least partly responsible for the emergence of episodic memory.
I am ambidextrous, that should give me a fantastic memory with the benefits of both hemispheres (that is when, combined with my dyslexia, it is not leading to total confusion!) BM
Read more in the Scientific American online
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Hypnotherapy May Not Work To Recover Lost Memories
September 4, 2001
A new study suggests that hypnosis doesn't help people recall events more accurately -- but it does tend to make people more confident of their inaccurate memories.
Researchers asked college students, including some who were under hypnosis, to give the dates of 20 national and international news events from the past 11 years. Those who were hypnotized were no more accurate than others in choosing the correct dates. However, those who were hypnotized were more reluctant to change their answers when they were told they might be wrong.
The results suggest that people may have too much faith that hypnosis can help them accurately recover lost memories, said Joseph Green, co-author of the study and associate professor of psychology at Ohio State University's Lima campus.
"Clearly, myths and misconceptions about hypnosis abound," Green said. "While hypnosis does not enhance the reliability of memory, there is some evidence that hypnosis leads to increased confidence in memories."
These results support earlier survey research co-authored by Green that found nearly nine of ten people in four countries believe that hypnosis can help someone remember something that they could not remember otherwise.
Green conducted the latest study with Steven Jay Lynn of the State University of New York at Binghamton. The study involved 96 college students who were asked to give their best estimate of the day, month and year that various events occurred. These included the date the Gulf War began, the day a bomb exploded in Atlanta during the Olympics and the date that Kurt Cobain of the rock band Nirvana committed suicide.
About half the students were hypnotized before performing the task, while the other half performed a progressive muscle relaxation exercise.
In addition to giving dates, the students were asked to rate how confident they were in the estimates they gave. Afterwards, the booklets with the date estimates were collected.
After 20 minutes, the students were told the booklets had been scored to determine if their dates were within three months of the actual date. All participants were told that if they had a red star on the back of the booklet, at least one, but maybe more of the dates were inaccurate. In fact, though, the researchers had put red stars on all the booklets. The students were then given 10 minutes to review and change any of their previous estimates and give new ratings of how confident they were of their date estimates.
Results showed that the students who were hypnotized were no more accurate than those in the relaxation group. On some of the questions, none of the students were within three months of the correct date. At best, 62.5 percent were within three months of the correct date of an event.
In their ratings, the students who were hypnotized were no more confident of their date estimates than were the other students, Green said. However, participants who were hypnotized were less likely to change their estimates when told some were wrong.
Participants in the hypnosis group changed only 16.9 percent of their answers, compared to the other group, who changed 24.6 percent of their answers.
The fact that students under hypnosis said they were no more confident of their answers than did others, but were still less likely to change their answers, suggests the belief in the power of hypnosis to improve memory operates outside of conscious awareness. "Those who were hypnotized tell you they are not confident in their answers, but their behavior -- the reluctance to change their answers -- suggests they must be more confident in their answers," Green said.
The reason may be the myths that surround hypnosis, he said. "It's widely believed that hypnosis somehow acts as a truth serum, that it unlocks memory and permits people to perform mental operations that they otherwise couldn't do," Green said.
I am suspicious of any technique which seeks to 'recover' lost memories in an artificial way. What people 'discover' under hypnosis is often what they believe the therapist, as the parent-authority figure wants to hear. This is how 'memories' of past lives are 'recovered.' For more about false memories see our Health News Archive article
"False Memories Easily Created". BM
Read more in Uniscience
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Win Some, Lose Some
August 22, 2001
People in their 20s don't usually complain about forgetting names or phone numbers or having trouble learning something new. But that's when memory and mental energy first start to decline, according to psychologist Denise Park. Park directs the Center for Aging and Cognition at the University of Michigan Institute for Social Research (ISR).
In studies of more than 350 men and women between the ages of 20 and 90 Park found that mental aging is a slippery slope, with continuous declines in processing power starting as soon as our 20s. This gradual reduction in cognitive capital is not really noticeable until the loss is substantial enough to affect everyday activities. "Younger adults in their 20s and 30s notice no losses at all, even though they are declining at the same rate as people in their 60s and 70s, because they have more capital than they need," says Park.
But there is good news, too. An increase in experience and general knowledge, as measured by vocabulary, compensates for many of the losses, Park has found, with the crossroads coming around the age of 50 -- traditionally considered the beginning of wisdom.
Read more in Uniscience
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Visual Memory Stronger Than Current Theory Has It
July 30, 2001
Why is it that you can park your car at a huge mall and find it a few hours later without much problem?
The answer may lie in our ability to build up visual memories of a scene in a short period of time, according to a Rutgers study published in the journal Nature.
The study, "Persistence of Visual Memory for Scenes," authored by David Melcher, a graduate fellow in the department of psychology of Rutgers' Faculty of Arts and Sciences-New Brunswick, counters current thinking that visual memory is generally poor and that people quickly forget the details of what they have seen.
Melcher proved that even with very limited visual exposure to a scene, people are able to build up strong visual memories and, in fact, their recall of objects in the scene improved with each exposure.
Over the past two years, Melcher tested subjects in Psychology Professor Eileen Kowler's Eye Movements and Vision Laboratory at Rutgers, using hundreds of three-dimensional, computer-generated scenes of rooms that contained 12 unrelated objects such as an apple, a plant, a toy and a lamp.
The scenes were randomly selected and shown to subjects for as little as a quarter of a second to a maximum of four seconds. Immediately after, the subjects were asked to name as many of the items in that scene as they could recall. Melcher found that after viewing a scene, a subject might recall four objects and, when shown the scene again, might recall six. The more times a particular scene was shown, the more objects the subject could recall and identify.
"Surprisingly, subjects continued to build memory for the scene as if it had never left their sight, despite the fact that each view of a particular scene was separated by many other scenes over a period of several minutes," observed Melcher.
According to Melcher, these images aren't stored in short-term or long-term memory; they are preserved in medium-term memory, which lasts for a few minutes and appears to be specific to visual information as opposed to verbal information.
"Medium-term memory depends on the visual context of the scene, such as the background, furniture and walls, which seems to be key in the ability to keep in mind the location and identity of objects," he explained. "These disposable accumulated visual memories can be recalled in a few minutes if faced with that scene again, but are discarded in a day or two if the scene is not viewed again so they don't take up valuable memory space."
He also noted that when the objects in a scene were replaced with words, such as the word "apple" for an image of an apple, subjects lost the ability to build up memories; frequency of exposure in this case did not increase the number of words recalled.
In addition, if subjects were shown a scene that had an identical background to one previously viewed, but the objects or their location was changed, interference between the two scenes developed. As a result, subjects remembered fewer items than when seeing a totally new scene.
"What this means is that medium-term memory can be helpful, enabling us to quickly identify our surroundings without having to constantly visually scan our environment, but it can also be equally harmful to memory if the locations of objects are changed frequently," he said. "So, if you put your car keys on the dresser tonight and then on the kitchen table tomorrow and someplace else the next day, these previous memories of where you put the keys will begin to interfere with each other and cause confusion," he added. "What was great about this research is that it provided me with scientific reasons why I remembered things or didn't. Now I put my keys in the same place every day."
What this research also shows is that the human brain is programmed to allow us to find our way in places which, though not visited before, are part of a constant backgrounds (the jungle, or the savanna, or a mall car park). In survival terms this would have been very useful to our ancestors who didn't have road signs. BM
Reported in Uniscience
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'Memories' Reflect Culture
July 10, 2001
How American adults and preschool children recall their personal memories is consistently different from the way indigenous Chinese do, finds a Cornell University developmental psychologist.
These cultural differences are important, she says, "because how we remember personal experiences has a profound impact on our self and identity."
"Americans often report lengthy, specific, emotionally elaborate memories that focus on the self as a central character," says Qi Wang, an assistant professor of human development at Cornell. "Chinese tend to give brief accounts of general routine events that center on collective activities and are often emotionally neutral. "These individual-focused vs. group-oriented styles characterize the mainstream values in American and Chinese cultures, respectively."
Early childhood memories form the beginnings of what Wang calls "the autobiographical self" and provide a unique window through which to understand the interplay between memory and self, Wang says in a study published in the Journal of Personality and Social Psychology (August 2001). Researchers agree, Wang says, that the constructive process of autobiographical remembering is crucial for the development, expression and maintenance of a "dynamic self-concept."
In the study, Wang asked 119 American and 137 native Chinese college students to describe their earliest childhood memories. In addition to finding that the content and styles of autobiographical narratives are consistently different between Americans and Chinese, Wang also found that Americans, on average, cite earliest memories back to about age 3 1/2. Chinese, on average, recall their earliest memories from approximately six months later than Americans.
In another study, Wang and two colleagues at Harvard University asked 41 American and Chinese mothers to talk with their 3-year-olds about two shared past events and a story. American mothers and children used a more independent conversational style, in which mother and child elaborated on each other's responses and focused on the child's personal opinions, roles and feelings.
"The Chinese, however, elaborated rarely; rather, the mothers often posed and repeated factual questions, showing great concern with moral rules and behavioral standards.
"These findings suggest that children's early social-linguistic experiences shape their autobiographical remembering and may contribute to cultural differences in the age and content of earliest childhood memories,", Wang says.
Many recent studies (some reported on this site, such as "False Memories Easily Created") have shown that memory is rarely accurate but is easily manipulated and filtered through what we call the 'program'. A child's cultural mileau, as presented by his or her parents, forms part of this memory-influencing 'program'. BM
Reported in Uniscience
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False Memories Easily Created
July 2, 2001
Real, accurate, memory lasts for about 45 minutes. After that 'memories' are filtered through what we call the 'program' of beliefs and experiences that we have built up from earliest childhood. Often we 'remember' things that never happened or seek explanations and contexts for fragments of memory for which we have none.
In this way a young child's traumatic and fragmentally-remembered hospital visit can become a 'memory' (fervently believed) of an alien abduction. The child is forcibly removed from its parents for painful procedures and the gleaming operating theater with its frightening machines and masked and green-robed denizens is remembered as the abductors' space ship.
Now research has shown that faulty memories can be created in the adult brain from mis-matched fragments and can be a very powerful advertising tool. Just how effective this can be was demonstrated in an experiment conducted by University of Washington memory researchers Jacquie Pickrell and Elizabeth Loftus.
They found that about one-third of the people who were exposed to a fake print ad describing a visit to Disneyland and how they met and shook hands with Bugs Bunny said later they remembered or knew the event happened to them. The scenario described in the ad never occurred because Bugs Bunny is a Warner Bros. cartoon character and wouldn't be featured in any Walt Disney Co. property.
"The frightening thing about this study is that it suggests how easily a false memory can be created," said Pickrell. "It's not only people who go to a therapist who might implant a false memory or those who witness an accident and whose memory can be distorted who can have a false memory. Memory is very vulnerable and malleable. People are not always aware of the choices they make. This study shows the power of subtle association changes on memory."
In the new research, Pickrell and Loftus divided 120 subjects into four groups. The subjects were told they were going to evaluate advertising copy, fill out several questionnaires and answer questions about a trip to Disneyland.
- The first group read a generic Disneyland ad that mentioned no cartoon characters.
- The second group read the same copy and was exposed to a 4-foot-tall cardboard figure of Bugs Bunny that was casually placed in the interview room. No mention was made of Bugs Bunny.
- The third, or Bugs group, read the fake Disneyland ad featuring Bugs Bunny.
- The fourth, or double exposure group, read the fake ad and also saw the cardboard rabbit.
30 percent of the people in the Bugs group later said they remembered or knew they had met Bugs Bunny when they visited Disneyland and 40 percent of the people in the double exposure group reported the same thing.
"'Remember' means the people actually recall meeting and shaking hands with Bugs," explained Pickrell. "'Knowing' is they have no real memory, but are sure that it happened, just as they have no memory of having their umbilical cord being cut when they were born but know it happened.
"Creating a false memory is a process. Someone saying, 'I know it could have happened,' is taking the first step of actually creating a memory. If you clearly believe you walked up to Bugs Bunny, you have a memory."
In addition, Pickrell said, there is the issue of the consequence of false memories, or the ripple effects. People in the experiment who were exposed to the false advertising were more likely to relate Bugs Bunny to other things at Disneyland not suggested in the ad, such as seeing Bugs and Mickey Mouse together or seeing Bugs in the Main Street Electrical Parade.
"We are interested in how people create their autobiographical references, or memory. Through this process they might be altering their own memories," Pickrell said. Nostalgic advertising works in a similar manner. "Hallmark, McDonald's and Disney have very effective nostalgic advertising that can change people's buying habits. You may not have had a great experience the last time you visited Disneyland or McDonald's, but the ads may be creating the impression that you had a wonderful time and leaving viewers with that memory. If ads can get people to believe they had an experience they never had, that is pretty powerful."
This research is a strong argument against therapists who relentlessly hunt for a specific occurrence in early childhood even though the client can't remember it or who suggest to their client that they might have been 'sexually abused' in some way. The brain will often manufacture a 'memory' to satisfy the therapist.
Fortinberry-Murray practitioners (we provide professional training in the FM Method) are well aware of the somatic and behavioral traits which may indicate early abuse. However, they also keep in mind the malleability of memory and that the solution to problems created by that abuse lies in getting needs met in the present. BM
Reported in Uniscience
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Sleep It In
April 25, 2001
A study carried out by University of California in San Francisco (UCSF) has found that sleep, at least in cats, improves the animal's ability to learn and remember. The authors of the study say that the same is probably true for humans. For example students suffering revision 'nightmares' would be better off getting a good night's sleep than opting for late-night cramming sessions.
The researchers found sleep dramatically improves the way changes take place in the connections between nerve cells in the brain. These changes underpin the brain's control of behavior, learning and memory.
Researchers also found changes in the brain were linked to deep sleep rather than "dream sleep" associated with rapid eye movement (REM). Evidence that sleep plays a significant part in brain development will help researchers solve the mystery of why we sleep.
Dr Marcos Frank, the lead researcher, said: "Every animal sleeps -- even flies may have a state like sleep. But despite our understanding of the consequences of sleep loss on human performance, why the brain needs sleep has remained a mystery."
That sleep aids in longevity is well-established. Our ginger tabby cat, Sops, slept 85% of the time and lived to be over 20. That this sleeping helped his memory is attested to by the fact that Sops never forgot to wake up at feeding time. BM
Read more on BBC News
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Emotion Regulation and Memory
February 10, 2001
An article by Jane Richards and James Gross of Stanford University's Psychology Department in the current edition of Journal of Personality and Social Psychology shows the benefits of not keeping your cool. There are many ways of keeping your cool or repressing your emotions, the authors state. The question is: does regulating your emotions do you any cognitive harm?
We think of emotion suppression as being particularly adult, but frontal brain structures that allow for emotion regulation are evident in infants as young as 9 months, and by age 6 children have developed a sophisticated arsenal of emotion regulatory strategies. One theory says that by adulthood, managing how one looks and feels would have become an automatic response that one draws upon in everyday life and would be so ingrained that it would have no impact on cognitive activities such as memory.
A quite different possibility is that any sort of self-regulation depletes mental resources. The authors relate a study in which participants were shown an emotionally disturbing film. They were told to "try to deny any emotions you may feel.... When I look over the videotape of your facial expressions, I don't want to be able to tell which videotape you are watching." Results revealed that regulation participants (relative to a no-regulation control group) persevered for a shorter period of time on a subsequent handgrip task. In a similar study testing the effects of this emotion-regulation manipulation on a subsequent anagram task, regulation participants were found to solve fewer problems than no-regulation participants.
Apparently cognition -- attention, memory and concentration etc -- is a finite resource. You only have so much of it. Suppressing emotions for whatever reason reduces your cognitive ability because the suppression uses up much of this resource.
Now where did I put that @!?**$%@! pen?
Read the Stanford University article online on the Journal of Personality and Social Psychology
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Mashed Potatoes Improve Memory!
January 25, 2001
As reported in Psychology Today researchers at the University of Toronto have shown that eating common carbohydrates such as mashed potatoes can improve your memory for up to an hour after eating them. Pity we usually eat them at night before we sit down to remember the latest episode of NYPD Blue. Maybe breakfast cereals also help? Well barley is actually best. The study participants' memory improved 37% after eating barley, 32% after mashed potatoes and 8% after drinking something with glucose in it.
"We think it may have something to do with signals that gut peptides transmitted to the brain," lead author Randall J. Kaplan says. The study's long-term aim is to find food-based treatments for reducing memory loss in Alzheimer's and diabetes patients.
Really shows you that the brain/body connection is... (now where's the remains of last night's mashed potatoes?)
Reported in Psychology Today
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About the Author
Dr Bob Murray is a widely published psychologist and expert on emotional health and optimal relationships. Together with his wife and long-term collaborator Alicia Fortinberry, he is founder of the highly successful Uplift Program, and author of Raising an Optimistic Child (McGraw-Hill, 2006) and Creating Optimism (McGraw-Hill, 2004).
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