Problems

Trauma changes the brain even in those without PTSD

  • A review of previous research has compared brain activity in those with PTSD who experienced trauma, those who experienced trauma but didn't develop PTSD, and those who never experienced trauma.
  • Those who had PTSD had differential activity in two brain regions.
  • Those who had experienced trauma had differential activity in several brain regions associated with emotional regulation, regardless of whether they'd developed PTSD.

A meta-analysis of studies reporting brain activity in individuals with a diagnosis of PTSD has revealed differences between the brain activity of individuals with PTSD and that of groups of both trauma-exposed (those who had experienced trauma but didn't have a diagnosis of PTSD) and trauma-naïve (those who hadn't experienced trauma) participants.

The critical difference between those who developed PTSD and those who experienced trauma but didn't develop PTSD lay in the basal ganglia. Specifically:

  • PTSD brains compared with trauma-exposed controls showed differentially active regions of the basal ganglia
  • trauma-exposed brains compared with trauma-naïve controls revealed differences in the right anterior insula, precuneus, cingulate and orbitofrontal cortices, all known to be involved in emotional regulation
  • PTSD brains compared with both control groups showed differences in activity in the amygdala and parahippocampal cortex.

The finding is consistent with other new evidence from the researchers, that other neuropsychiatric disorders were also associated with specific imbalances in specific brain networks.

The findings suggest that, while people who have experienced trauma may not meet the threshold for a diagnosis of PTSD, they may have similar changes within the brain, which might make them more vulnerable to PTSD if they experience a subsequent trauma.

The finding also suggests a different perspective on PTSD — that it “may not actually be abnormal or a 'disorder' but the brain's natural reaction to events and experiences that are abnormal”.

http://www.eurekalert.org/pub_releases/2015-08/uoo-tec080315.php

Reference: 

Topics: 

tags problems: 

Coping with cognitive decline in MS

Cognitive impairment affects 40-65% of people with MS. Why? In the past year, a number of studies have helped us build a better picture of the precise nature of cognitive problems that may affect multiple sclerosis sufferers:

  • poorer performance on executive function tasks is fully explained by slower processing speed (which is presumably a function of the degradation in white matter characteristic of MS)
  • slowing in processing speed is associated with weaker connections between the executive area and the brain regions involved in carrying out cognitive tasks
  • cognitive reserve helps counter the decline in memory and cognitive efficiency
  • brain reserve (greater brain volume, ie less shrinkage) helps counter the decline in cognitive efficiency
  • working memory capacity explains the link between cognitive reserve and long-term memory
  • subjective cognitive fatigue is linked to the time spent on the task, not on its difficulty
  • mnemonic training helps protect against cognitive decline, but appears to be less helpful in those with slow processing speed.

What all this implies is that a multi-pronged approach is called for, involving:

  • working memory training
  • training in effective memory strategies
  • practice in breaking down cognitive tasks into more manageable chunks of time
  • practice in framing tasks to accommodate slower processing speed
  • physical and mental activities that encourage neurogenesis (growing more neurons) and synaptogenesis (growing more connections).

Here's some more detail on those studies:

Slow processing speed accounts for executive deficits in MS

A study of 50 patients with MS and 28 healthy controls found no differences in performance on executive function tasks when differences in processing speed were controlled for. In other words, although MS patients performed more poorly than controls on these tasks, the difference was fully accounted for by the differences in processing speed. There were no differences in performance when there was no processing speed component to the task. Similarly, MS patients with a greater degree of brain atrophy performed more poorly than those with less atrophy, but again, this only occurred when there was a processing speed aspect to the task, and was fully accounted for by processing speed differences.

http://www.eurekalert.org/pub_releases/2014-09/kf-kfs091614.php

[3939] Leavitt, V. M., Wylie G., Krch D., Chiaravalloti N. D., DeLuca J., & Sumowski J. F.
(2014).  Does slowed processing speed account for executive deficits in multiple sclerosis? Evidence from neuropsychological performance and structural neuroimaging..
Rehabilitation Psychology. 59(4), 422 - 428.

Functional connectivity factor in cognitive decline in MS

A brain imaging study involving 29 participants with relapsing-remitting MS and 23 age- and sex- matched healthy controls found that, as expected, those with MS were much slower on a processing speed task, although they were as accurate as the controls. This slowing was associated with weaker functional connections between the dorsolateral prefrontal cortex (the executive area) and the regions responsible for carrying out the task. It's thought that this is probably due to decreased white matter (white matter degradation is symptomatic of MS).

http://www.eurekalert.org/pub_releases/2015-07/cfb-srb070715.php

[3938] Hubbard, N. A., Hutchison J. L., Turner M. P., Sundaram S., Oasay L., Robinson D., et al.
(2015).  Asynchrony in Executive Networks Predicts Cognitive Slowing in Multiple Sclerosis.
Neuropsychology.

Brain and cognitive reserve protect against cognitive decline in MS

A study compared memory, cognitive efficiency, vocabulary, and brain volume in 40 patients with MS, at baseline and 4.5 years later. After controlling for disease progression, they found that those with better vocabulary (a proxy for cognitive reserve) experienced less decline in memory and cognitive efficiency, and those with less brain atrophy over the period showed less decline in cognitive efficiency.

Cognitive efficiency is a somewhat fuzzy concept, but essentially has to do with how much time and effort you need to acquire new knowledge; in this study, it was assessed using the Symbol Digit Modalities Test and Paced Auditory Serial Addition Task, two tests commonly used to detect cognitive impairment in MS patients.

http://www.eurekalert.org/pub_releases/2014-04/kf-mrf043014.php

[3943] Sumowski, J. F., Rocca M. A., Leavitt V. M., Dackovic J., Mesaros S., Drulovic J., et al.
(2014).  Brain reserve and cognitive reserve protect against cognitive decline over 4.5 years in MS.
Neurology. 82(20), 1776 - 1783.

Working memory capacity accounts for link between cognitive reserve & better memory

A study involving 70 patients with MS has found that working memory capacity explained the relationship between cognitive reserve and long-term memory, suggesting that interventions targeted at working memory may help protect against decline in long-term memory.

http://www.eurekalert.org/pub_releases/2014-09/kf-kfm090914.php

[3941] Sandry, J., & Sumowski J. F.
(2014).  Working Memory Mediates the Relationship between Intellectual Enrichment and Long-Term Memory in Multiple Sclerosis: An Exploratory Analysis of Cognitive Reserve.
Journal of the International Neuropsychological Society. 20(08), 868 - 872.

Cognitive fatigue linked to time on task, not difficulty

A study investigating cognitive fatigue in 32 individuals with MS and 24 controls has found that subjective and objective fatigue were independent of one another, and that subjective cognitive fatigue increased as time on task increased. This increase in cognitive fatigue was greater in the MS group. No relationship was found between cognitive fatigue and cognitive load. Fatigue was greater for the processing speed task than the working memory task.

In other words, the length of time spent is far more important than the difficulty of the task.

http://www.eurekalert.org/pub_releases/2015-01/kf-kfr012115.php

[3940] Sandry, J., Genova H. M., Dobryakova E., DeLuca J., & Wylie G.
(2014).  Subjective cognitive fatigue in multiple sclerosis depends on task length.
Frontiers in Neurology. 5, 214.

Story mnemonic training helps some

A series of small studies have found cognitive benefits for MS patients from a 10-session training program designed to build their memory skills using a modified story mnemonic. The MEMREHAB Trial involved 85 patients with MS, of whom 45 received the training. In the most recent analyses of the data, the benefits were found to be maintained six months later, but unfortunately, it appears that those with processing speed deficits gain less benefit from the training.

The training consists of four 45-minute sessions focused on building imagery skills, in which participants were given a story with highly visualizable scenes and given facilitated practice in using visualization to help them remember the story. In the next four sessions, they were given lists of words and instructed in how to build a memorable story from these words, that they could visualize. The sessions employed increasingly unrelated word lists. In the final two sessions, participants were taught how to apply the technique in real-world situations.

http://www.eurekalert.org/pub_releases/2014-08/kf-kfs080814.php

[3936] Chiaravalloti, N. D., & DeLuca J.
(2015).  The influence of cognitive dysfunction on benefit from learning and memory rehabilitation in MS: A sub-analysis of the MEMREHAB trial.
Multiple Sclerosis (Houndmills, Basingstoke, England).

[3937] Dobryakova, E., Wylie G. R., DeLuca J., & Chiaravalloti N. D.
(2014).  A pilot study examining functional brain activity 6 months after memory retraining in MS: the MEMREHAB trial.
Brain Imaging and Behavior. 8(3), 403 - 406.

Topics: 

tags memworks: 

tags problems: 

tags strategies: 

Gentle exercise during chemotherapy has significant cognitive benefits

A six-week study involving 619 cancer patients has found that those who took part in a simple home-based exercise program significantly reduced their cognitive impairment ('chemo-brain'). The EXCAP (Exercise for Cancer Patients) was developed by the researchers some years ago, and this evaluation was a phase III randomized study for early-stage chemotherapy patients. Half the group were given standard care (no exercise during chemotherapy), while the others were given instruction to walk daily and carry out low-to-moderate resistance band training for 10 minutes, 5 days a week.

This very modest increase in exercise (the 'no-exercise' group walked on average 3,800 steps a day, while the excap group walked on average 5,000 steps) had significant effects:

  • lower levels of inflammation
  • less brain 'fogginess'
  • fewer memory problems
  • greater mobility.

Exercisers who received chemotherapy in 2-week cycles reported the greatest benefits, compared to other timing cycles.

http://www.futurity.org/exercise-chemotherapy-932492/

http://www.urmc.rochester.edu/news/story/index.cfm?id=4333

Reference: 

The findings were presented at the American Society of Clinical Oncology (ASCO) annual meeting on June 1, by Karen Mustian.

Source: 

Topics: 

tags lifestyle: 

tags problems: 

Interruptions impact the quality of creative work

In 2013 I reported how a 3-second interruption while doing a task doubled the rate of sequence errors, while a 4s one tripled it. A new study has attempted to measure just how much ongoing interruptions can negatively affect the quality of a complex creative task.

Topics: 

tags problems: 

Gum disease may have ties to Alzheimer’s

Analysis of post-mortem with and without dementia has found lipopolysaccharide, a component of an oral bacterium (Porphyromonas gingivalis), in four out of 10 Alzheimer’s disease brain samples, but not in any of the 10 brains of people who didn’t have Alzheimer’s.

Gingivitis is extremely common, and about 64% of American seniors (65+) have moderate or severe periodontal disease.

The finding adds to evidence linking gum disease and Alzheimer’s.

http://www.futurity.org/alzheimers-may-ties-gum-disease/

Reference: 

Topics: 

tags problems: 

Stress & anxiety

Older news items (pre-2010) brought over from the old website

Short stressful events may improve working memory

We know that chronic stress has a detrimental effect on learning and memory, but a new rat study shows how acute stress (a short, sharp event) can produce a beneficial effect. The rats, trained to a level of 60-70% accuracy on a maze, were put through a 20-minute forced swim before being run through the maze again. Those who experienced this stressful event were better at running the maze 4 hours later, and a day later, than those not forced through the stressful event. It appears that the stress hormone corticosterone (cortisol in humans) increases transmission of the neurotransmitter glutamate in the prefrontal cortex and improves working memory. It also appears that chronic stress suppresses the transmission of glutamate in the prefrontal cortex of male rodents, while estrogen receptors in female rodents make them more resilient to chronic stress than male rats.

[1157] Yuen, E. Y., Liu W., Karatsoreos I. N., Feng J., McEwen B. S., & Yan Z.
(2009).  Acute stress enhances glutamatergic transmission in prefrontal cortex and facilitates working memory.
Proceedings of the National Academy of Sciences of the United States of America. 106(33), 14075 - 14079.

http://www.eurekalert.org/pub_releases/2009-07/uab-sse072309.php

Stressed brains rely on habit

And another rat study has found that rats stressed repeatedly and unpredictably for three weeks were more likely than unstressed animals to continue performing habitual behaviors, even when it no longer made sense to do so. This behavior was correlated with reductions in the prelimbic cortex of the medial prefrontal cortex and the dorsomedial striatum (both implicated in goal-directed actions), and increases in the size of the dorsolateral striatum (necessary for habit). The finding follows on from previous research showing that habit formation involves a switch between neural circuits associated with goal-directed behavior and those controlling habitual behavior. The findings have implications for therapies for stress-related disorders and addictive behavior.

[517] Dias-Ferreira, E., Sousa J. C., Melo I., Morgado P., Mesquita A. R., Cerqueira J. J., et al.
(2009).  Chronic Stress Causes Frontostriatal Reorganization and Affects Decision-Making.
Science. 325(5940), 621 - 625.

http://www.the-scientist.com/blog/display/55873/

Stress disrupts task-switching, but the brain can bounce back

A new neuroimaging study involving 20 male M.D. candidates in the middle of preparing for their board exams has found that they had a harder time shifting their attention from one task to another after a month of stress than other healthy young men who were not under stress. The finding replicates what has been found in rat studies, and similarly correlates with impaired function in an area of the prefrontal cortex that is involved in attention. However, the brains recovered their function within a month of the end of the stressful period.

[829] Liston, C., McEwen B. S., & Casey B. J.
(2009).  Psychosocial stress reversibly disrupts prefrontal processing and attentional control.
Proceedings of the National Academy of Sciences. 106(3), 912 - 917.

Full text available at http://www.pnas.org/content/106/3/912.abstract
http://www.eurekalert.org/pub_releases/2009-01/ru-sdh012709.php

Psychological distress, not depression, linked to increased risk of stroke

A study following 20,627 people for an average of 8.5 years has found that psychological distress was associated with an increased risk of stroke and that the risk of stroke increased the more distress the participants reported. This association remained the same regardless of cigarette smoking, systolic blood pressure, overall blood cholesterol, obesity, previous heart attack, diabetes, social class, education, high blood pressure treatment, family history of stroke and recent antidepressant medication use. However, there was no increased risk for people who had experienced an episode of major depression in the past year or at any point in their lifetime.

[1298] Surtees, P. G., Wainwright N. W. J., Luben R. N., Wareham N. J., Bingham S. A., & Khaw K. - T.
(2008).  Psychological distress, major depressive disorder, and risk of stroke.
Neurology. 70(10), 788 - 794.

http://www.eurekalert.org/pub_releases/2008-03/aaon-pdn022608.php

Short-term stress can affect learning and memory

We know that long-lasting, severe stress can impair cell communication in the hippocampus. Now rodent studies have demonstrated that the same outcome can happen with short-term stress. But rather than involving the familiar stress hormone cortisol, acute stress activated corticotropin releasing hormones, which led to the rapid disintegration of dendritic spines in the hippocampus, thus limiting the ability of synapses to collect and store memories.

[981] Chen, Y., Dube C. M., Rice C. J., & Baram T. Z.
(2008).  Rapid Loss of Dendritic Spines after Stress Involves Derangement of Spine Dynamics by Corticotropin-Releasing Hormone.
J. Neurosci.. 28(11), 2903 - 2911.

http://www.eurekalert.org/pub_releases/2008-03/uoc--ssc031008.php

Correct levels of stress hormones boost learning

Although it’s known that cortisol production is related to stress and has an impact on learning in humans, that impact is not well understood, because of the difficulties of controlling cortisol levels in humans. A study using ground squirrels has now found that they learn more quickly if they have a modest amount of cortisol, rather than either high or low levels of cortisol.

[252] Mateo, J. M.
(2008).  Inverted-U shape relationship between cortisol and learning in ground squirrels.
Neurobiology of Learning and Memory. 89(4), 582 - 590.

http://www.eurekalert.org/pub_releases/2008-03/uoc-rws031208.php

Stress hormone impacts memory, learning in diabetic rodents

A rodent study sheds light on why diabetes can impair cognitive function. The study found that increased levels of a stress hormone (called cortisol in humans) in diabetic rats impaired synaptic plasticity and reduced neurogenesis in the hippocampus. When levels returned to normal, the hippocampus recovered. Cortisol production is controlled by the hypothalamic-pituitary axis (HPA). People with poorly controlled diabetes often have an overactive HPA axis and excessive cortisol.

[1050] Stranahan, A. M., Arumugam T. V., Cutler R. G., Lee K., Egan J. M., & Mattson M. P.
(2008).  Diabetes impairs hippocampal function through glucocorticoid-mediated effects on new and mature neurons.
Nature Neuroscience. 11(3), 309 - 317.

http://www.eurekalert.org/pub_releases/2008-02/nioa-shi021508.php

How stress affects memory

We know stress affects memory. Now a rat study tells us one of the ways it does that. Cell recordings in the hippocampus revealed that, when a mouse moves from one location to another, particular cells fired at each location. When the mouse returned to an earlier location, the same cells fire. However, following stress, the cells that fired in a particular location still fired at the same location, but tended to fire at a different frequency. Stress also reduce the level of LTP at the synapses.

[1295] Kim, J. J., Lee H. J., Welday A. C., Song EY., Cho J., Sharp P. E., et al.
(2007).  Stress-induced alterations in hippocampal plasticity, place cells, and spatial memory.
Proceedings of the National Academy of Sciences. 104(46), 18297 - 18302.

http://www.sciencentral.com/articles/view.php3?article_id=218393035

Highly accomplished people more prone to failure than others when under stress

One important difference between those who do well academically and those who don’t is often working memory capacity. Those with a high working memory capacity find it easier to read and understand and reason, than those with a smaller capacity. However, a new study suggests there is a downside. Such people tend to heavily rely on their abundant supply of working memory and are therefore disadvantaged when challenged to solve difficult problems, such as mathematical ones, under pressure — because the distraction caused by stress consumes their working memory. They then fall back on the less accurate short-cuts that people with less adequate supplies of working memory tend to use, such as guessing and estimation. Such methods are not made any worse by working under pressure. In the study involving 100 undergraduates, performance of students with strong working memory declined to the same level as those with more limited working memory, when the students were put under pressure. Those with more limited working memory performed as well under added pressure as they did without the stress.

The findings were presented February 17 at the annual meeting of the American Association for the Advancement of Science.

http://www.eurekalert.org/pub_releases/2007-02/uoc-hap021607.php

Lifestyle changes improve seniors’ memory surprisingly quickly

A small 14-day study found that those following a memory improvement plan that included memory training, a healthy diet, physical exercise, and stress reduction, showed a 5% decrease in brain metabolism in the dorsal lateral prefrontal region of the brain (involved in working memory) suggesting they were using their brain more efficiently. This change in activity was reflected in better performance on a cognitive measure controlled by this brain region, and participants reported that they felt their memory had improved. The memory training involved doing brainteasers, crossword puzzles and memory exercises. Diet involved eating 5 small meals daily (to prevent fluctuations in blood glucose levels) that were rich in omega-3 fats, low-glycemic index carbohydrates (e.g., whole grains) and antioxidants. Physical exercise involved brisk walking and stretching, and stress reduction involved stretching and relaxation exercises.

The study was presented at the American College of Neuropsychopharmacology's Annual Meeting on December 11-15, in Hawaii.

http://www.eurekalert.org/pub_releases/2005-12/g-nsf121205.php

Stress interferes with problem-solving; Beta-blocker may help

New research suggests that an experience as simple as watching graphically violent or emotional scenes in a movie can induce enough stress to interfere with problem-solving abilities, and that a beta-blocker medication could promote the ability to think flexibly under stressful conditions. Neither the stress nor the beta-blocker affected memory. The research not only has implications for understanding the range of effects of stress on thinking, but could also have broader clinical implications for patients with anxiety disorders or substance abuse problems.

Renner, K., Alexander, J., Hillier, A., Smith, R. & Tivarus, M. 2005. Presented at the annual Society for Neuroscience meeting in Washington, D.C.

http://www.eurekalert.org/pub_releases/2005-11/osu-siw110905.php

Early life stress can lead to memory loss and cognitive decline in middle age

Age-related cognitive decline is probably a result of both genetic and environmental factors. A rat study has demonstrated that some of these environmental factors may occur in early life. Among the rats, emotional stress in infancy showed no ill effects by the time the rats reached adulthood, but as the rats reached middle age, cognitive deficits started to appear in those rats who had had stressful infancies, and progressed much more rapidly with age than among those who had had nurturing infancies. Middle-aged rats who had been exposed to early life emotional stress showed deterioration in brain-cell communication in the hippocampus.

[1274] Brunson, K. L., Kramar E., Lin B., Chen Y., Colgin L L., Yanagihara T. K., et al.
(2005).  Mechanisms of Late-Onset Cognitive Decline after Early-Life Stress.
J. Neurosci.. 25(41), 9328 - 9338.

http://www.eurekalert.org/pub_releases/2005-10/uoc--els100605.php

Stress bad for the brain

A study of older adults for three to six years has found that those with continuous high levels of the stress hormone cortisol performed poorly on memory tests and had a 14% smaller hippocampus. A further study involving young adults and children between the ages of six and fourteen found that even an acute increase in cortisol can lead to reversible memory impairments in young adults, and that children from low socio-economic status environments had higher cortisol levels than those from high SES homes. Children from low SES homes tended to process positive and negative attributes more negatively than children from high SES homes, and this type of processing was significantly related to basal cortisol levels at ages 10, 12 and 14.

[1415] Lupien, S. J., Fiocco A. J., Wan N., Maheu F., Lord C., Schramek T., et al.
(2005).  Stress hormones and human memory function across the lifespan.
Psychoneuroendocrinology. 30(3), 225 - 242.

http://www.eurekalert.org/pub_releases/2005-05/mu-tst051705.php

Anxiety adversely affects those who are most likely to succeed at exams

It has been thought that pressure harms performance on cognitive skills such as mathematical problem-solving by reducing the working memory capacity available for skill execution. However, a new study of 93 students has found that this applies only to those high in working memory. It appears that the advantage of a high working memory capacity disappears when that attention capacity is compromised by anxiety.

[355] Beilock, S. L., & Carr T. H.
(2005).  When high-powered people fail: working memory and "choking under pressure" in math.
Psychological Science: A Journal of the American Psychological Society / APS. 16(2), 101 - 105.

http://www.eurekalert.org/pub_releases/2005-02/bpl-wup020705.php

Anxiety good for memory recall, bad for solving complex problems

Cognitive tests given to 19 first-year medical students one to two days before a regular classroom exam, and then a week after the exam, found that, before the exam, students were better able to accurately recall a list of memorized numbers, but did less well on tests that required them to consider many possibilities in order to come up with a reasonable answer. A week after the exam, the opposite was true. It is assumed that the difference in results reflects the effects of stress.

Jessa Alexander & David Beversdorf presented their findings on October 25 in San Diego at the annual Society for Neuroscience conference.

http://www.eurekalert.org/pub_releases/2004-10/osu-agf101904.php

Estrogen effect on memory influenced by stress

The question of whether estrogen helps memory and cognition in women has proven surprisingly difficult to answer, with studies giving conflicting results. Now it seems the answer to that confusion is: it depends. And one of the things it depends on may be the level of stress the woman is experiencing. A rat study has found that the performance of female rats in a water maze was affected by the interaction of hormone level (whether the rat was estrous or proestrous) with water temperature (a source of physical stress). Those rats with high hormone levels did better when the water was warm, while those with low hormone levels did better when the water was cold. The researchers suggest both timing and duration of stress might be factors in determining the effect of hormones on cognition.

[384] Rubinow, M. J., Arseneau L. M., Beverly L. J., & Juraska J. M.
(2004).  Effect of the Estrous Cycle on Water Maze Acquisition Depends on the Temperature of the Water..
Behavioral Neuroscience. 118(4), 863 - 868.

http://www.eurekalert.org/pub_releases/2004-08/uoia-sss082704.php

Stress reactions no guarantee of authenticity

Physical stress reactions have often been taken as evidence for the authenticity of a memory. A recent study investigated people with “memories” of alien abductions (on the grounds that these are the memories least likely to be true) and found that those who believed they had been abducted by aliens responded physically to recall of that memory in the same way as to recall of other, true, stressful events. The finding suggests that a person’s reaction to a memory is no evidence for whether or not it truly happened.

[1161] McNally, R. J., Lasko N. B., Clancy S. A., Macklin M. L., Pitman R. K., & Orr S. P.
(2004).  Psychophysiological responding during script-driven imagery in people reporting abduction by space aliens.
Psychological Science: A Journal of the American Psychological Society / APS. 15(7), 493 - 497.

http://www.eurekalert.org/pub_releases/2004-06/aps-ptw062104.php

Stress no aid to memory

Numerous studies have questioned the accuracy of recall of traumatic events, but the research is often dismissed as artificial and not intense enough to simulate real-life trauma. A new study has used real stress: 509 active duty military personnel enrolled in survival school training were deprived of food and sleep 48 hours and then interrogated. A day later, only 30% of those presented with a line-up could identify the right person, only 34% identified their interrogator from a photo-spread and 49% from single photos shown sequentially (putting the interrogator in the same clothing boosted correct identification to 66%). Thirty people even got the gender wrong. Those subjected to physical threats (half the participants) performed worse.

[269] Morgan, C. A., Hazlett G., Doran A., Garrett S., Hoyt G., Thomas P., et al.
(Submitted).  Accuracy of eyewitness memory for persons encountered during exposure to highly intense stress.
International Journal of Law and Psychiatry. 27(3), 265 - 279.

http://www.newscientist.com/news/news.jsp?id=ns99995089
http://www.eurekalert.org/pub_releases/2004-06/yu-emp060304.php
http://www.eurekalert.org/pub_releases/2004-06/ns-mfy060904.php

Anxiety over math blocks learning

The so-called "math block" is notorious - why do we have such a term? Do we talk about a "geography block", or a "physics block"? But we do talk of a reading block. Perhaps the reason for both is the same.
The amount of information you can work with at one time has clear limits, defined by your working memory capacity. When we are anxious, part of our working memory is taken up with our awareness of these fears and worries, leaving less capacity available for processing (which is why students who are very anxious during exams usually perform well below their capabilities). Processes such as reading and working with numbers are very sensitive to working memory capacity because they place such demands on it.
A recently reported study by Mark H. Ashcraft and Elizabeth P. Kirk, both psychologists at Cleveland (Ohio) State University, provides the first solid evidence that, indeed, math-anxious people have working memory problems as they do math.

[2549] Ashcraft, M. H., & Kirk E. P.
(2001).  The relationships among working memory, math anxiety, and performance.
Journal of Experimental Psychology: General. 130(2), 224 - 237.

http://www.sciencenews.org/20010630/fob4.asp

tags memworks: 

Pain

Topic summary at

Older news items (pre-2010) brought over from the old website

Chronic pain can impair working memory

A study of 24 patients with chronic pain has found that 2/3 of them showed cognitive impairment on attentional tasks on days when their pain was high (i.e. without receiving a pain-reducing procedure).

Dick, B.D. & Rashiq, S. 2007. Disruption of Attention and Working Memory Traces in Individuals with Chronic Pain. Anesthesia & Analgesia, 104 (5), 1223-1229.

http://www.sciencedaily.com/releases/2007/05/070517142536.htm
http://www.eurekalert.org/pub_releases/2007-05/uoa-cpc051707.php

Does migraine protect your memory?

A long-running study involving 1,448 women, of whom 204 had migraine, has found that, while women with migraine performed worse on cognitive tests at the beginning of the study, their performance declined 17% less over 12 years than women without migraine. The benefit was restricted to women over 50 who experience migraine with aura. It’s possible that some medications for migraine may have a protective effect, but the researchers did account for this possibility and the medications showed no indication of a significant protective effect. It is possible that women with migraine may change their diet or behavior in some way that might improve cognition. It’s also possible that there is some underlying biological mechanism, such as changes in blood vessels or underlying differences in brain activity.

Kalaydjian, A., Zandi, P.P., Swartz, K.L., Eaton, W.W. & Lyketsos, C. 2007. How migraines impact cognitive function: Findings from the Baltimore ECA. Neurology, 68 (17), 1417-1424.

http://www.eurekalert.org/pub_releases/2007-04/aaon-dmp041707.php

Chronic back pain shrinks 'thinking parts' of the brain

A new study has found chronic back pain shrinks the brain by as much as 11% — equivalent to the amount of gray matter lost in 10 to 20 years of normal aging. Loss in brain density is related to pain duration, indicating that 1.3 cubic centimeters of gray matter are lost for every year of chronic pain. The study compared 26 participants with chronic back pain for more than a year with matched normal subjects.

Apkarian, A.V., Sosa, Y., Sonty, S., Levy, R.M., Harden, R.N., Parrish, T.B. & Gitelman, D.R. 2004. Chronic Back Pain Is Associated with Decreased Prefrontal and Thalamic Gray Matter Density. Journal of Neuroscience, 24, 10410-10415.

http://www.eurekalert.org/pub_releases/2004-11/nu-cbp111504.php

tags problems: 

Anesthesia

Older news items (pre-2010) brought over from the old website

Anesthesia exposure before age 3 found not to impact cognitive performance

A twin study challenges findings that receiving anesthesia at a very young age (below four) is associated with subsequent learning problems. The Dutch study involved 1,143 pairs of identical twins, and compared groups where both twins had been exposed to anesthesia before age 3, where neither had been exposed to anesthesia, or where only one member of the pair had been exposed to anesthesia. Cognitive performance at age 12 was assessed from a standardized national exam administered to all children in the Netherlands at that age. It was found that there was no difference in cognitive performance between twins where one had been exposed to anesthesia and the other had not. It therefore seems likely that the association is due to children likely to undergo surgery early in life having significant medical problems that are associated with a vulnerability to learning disabilities.

[1217] Bartels, M., Althoff R. R., & Boomsma D. I.
(2009).  Anesthesia and cognitive performance in children: no evidence for a causal relationship.
Twin Research and Human Genetics: The Official Journal of the International Society for Twin Studies. 12(3), 246 - 253.

http://www.eurekalert.org/pub_releases/2009-08/uov-grn080409.php

Common pediatric anesthesia drugs cause brain damage and learning and memory problems in infant rats

A new study has found that drugs commonly used to anesthetize children can cause brain damage and long-term learning and memory disturbances in infant rats. The rats appeared to behave normally in most other ways, and there were no outward signs of brain damage.

[207] Jevtovic-Todorovic, V., Hartman R. E., Izumi Y., Benshoff N. D., Dikranian K., Zorumski C. F., et al.
(2003).  Early Exposure to Common Anesthetic Agents Causes Widespread Neurodegeneration in the Developing Rat Brain and Persistent Learning Deficits.
J. Neurosci.. 23(3), 876 - 882.

http://www.eurekalert.org/pub_releases/2003-02/wuso-cpa013003.php

tags lifestyle: 

Health in Aging

Short-term declines in cognitive function can occur in elderly subjects after surgery, and persists in a small percentage.

Heart bypass surgery in particular is associated with cognitive decline - estimates of its prevalence range from 33% to 82%. This decline may persist in as many as 42% of patients. Age and level of education are both factors in determining the likelihood of long-term decline. The presence of a gene (apolipoprotein E4) carried by some 25% of the population may also increase the likelihood of decline after bypass surgery. There also seems to be a link between post-operative fever and cognitive decline. Long-term decline in cognitive function may be more a result of cardiovascular risk factors than the surgery itself.

High blood pressure in those over 60 seems to be associated with greater risk of cognitive decline.

High blood pressure and other circulatory problems, such as cardiovascular risk factors and diabetes, are linked to cognitive decline, perhaps through causing abnormalities in the white matter of elderly persons' brains.

Those with the gene ApoE4 also appear to have more difficulty recovering from traumatic brain injury.

Two drugs used for Alzheimer's have also been found to help those suffering from dementia following stroke.

A specific skills approach is having some success in helping those who suffer from attention problems following stroke.

 

See separate pages for

Depression

Diabetes

Heart health

Inflammation & infection

Sleep problems

Stroke

Surgery

Older news items (pre-2010) brought over from the old website

Common medications associated with cognitive decline in elderly

A study of over 500 relatively healthy men aged 65 years or older with high blood pressure has found that chronic use of medications with anticholinergic properties was associated with impairment in verbal memory and the ability to perform daily living tasks. The degree of impairment increased proportionally to the total amount of drug exposure. This effect was independent of age, education, morbidities, and severity of hypertension.

Han, L., Agostini, J.V. & Allore, H.G. 2008. Cumulative Anticholinergic Exposure Is Associated with Poor Memory and Executive Function in Older Men. Journal of the American Geriatrics Society, 56 (12), 2203-2210.

http://www.eurekalert.org/pub_releases/2009-01/w-cma012609.php

Using anti-cholinergic drugs may increase cognitive decline

The Religious Orders Study has thrown up more data, this time on the subject of anticholinergic medication. Over an eight year period, 679 of the 870 elderly participants took at least one medication with anticholinergic properties. The study found those people who took anticholinergic drugs saw their rate of cognitive function decline 1.5 times as fast as those people who did not take the drugs. Anticholinergic properties are found in many medicines, such as medicines for stomach cramps, ulcers, motion sickness, and urinary incontinence.

The research was presented at the American Academy of Neurology Annual Meeting in Chicago, April 12–19.

http://www.eurekalert.org/pub_releases/2008-04/aaon-uad040208.php

Injection of human umbilical cord blood helps aging brain

A rat study has found that a single intravenous injection of human umbilical cord blood mononuclear cells in aged rats significantly improved the microenvironment of the aged hippocampus and rejuvenated the aged neural stem/progenitor cells. The increase in neurogenesis seemed to be due to a decrease in inflammation. The results raise the possibility of cell therapy to rejuvenate the aged brain.

Bachstetter, A.D. et al. 2008. Peripheral injection of human umbilical cord blood stimulates neurogenesis in the aged rat brain. BMC Neuroscience, 9, 22. 

http://www.physorg.com/news124384387.html

Relationship between statins and cognitive decline more complex than thought

Previous studies of a link between statins (which protect against cardiovascular disease) and cognitive decline have produced inconsistent results. A three year epidemiological study of older African Americans has now found cognitive decline in statin users was less than those who did not take statins, but those who continued to take statins from 2001 to 2004 had greater cognitive decline than those who were taking statins in 2001 but were no longer taking them in 2004. The finding that the benefit is stronger for those who had discontinued use than for continuous users points to a complex association between statins and cognitive decline.

Szwast, S.J. et al. 2007. Association of statin use with cognitive decline in elderly African Americans Neurology, 69, 1873-1880. 

http://www.eurekalert.org/pub_releases/2007-11/iu-rbs110207.php

High-normal uric acid linked with mild cognitive impairment in the elderly

A study of 96 older adults has found that those with uric-acid levels at the high end of the normal range had the lowest scores on tests of mental processing speed, verbal memory and working memory. The correlation persisted even when controlled for age, sex, weight, race, education, diabetes, hypertension, smoking and alcohol abuse. Uric acid levels increase with age, and higher levels are linked with high blood pressure, atherosclerosis, Type 2 diabetes and the "metabolic syndrome" of abdominal obesity and insulin resistance — all known risk factors for dementia. Because uric acid levels are so easily tested, the finding may suggest a valuable biological marker for very early cognitive problems in old age.

Schretlen, D.J. et al. 2007. Serum Uric Acid and Cognitive Function in Community-Dwelling Older Adults. Neuropsychology, 21 (1)

http://www.eurekalert.org/pub_releases/2007-01/apa-hua122706.php

Drug reverses aging effect on memory process

Rat studies suggest that a drug made to enhance memory triggers a natural mechanism in the brain that fully reverses age-related memory loss, even after the drug itself has left the body. In middle-aged rats given ampakines twice a day for four days, there was a significant increase in the production of brain-derived neurotrophic factor (BDNF), a protein known to play a key role in memory formation, and in long-term potentiation (LTP), the process by which the connection between the brain cells is enhanced and memory is encoded. Deficits in LTP occur with age. This restoration of LTP was found in the brains even after the ampakines had been cleared from the animals' bodies.

Rex, C.S. et al. 2006. Restoration of Long-Term Potentiation in Middle-Aged Hippocampus After Induction of Brain-Derived Neurotrophic Factor. Journal of Neurophysiology, 96, 677-685.

http://www.sciencedaily.com/releases/2006/07/060727154900.htm

Nicotine patch may alleviate 'senior moments'

A small preliminary clinical trial has found that four weeks of nicotine skin patches helped decision-making and attention in people with age-associated memory impairment (the mildest form of cognitive impairment in seniors). Given the health risks of smoking, and health risks associated with nicotine patches, it is too early to recommend the use of nicotine to improve memory, however. Nicotine mimics the brain chemical acetylcholine, a nerve signal that plays a role in learning and memory.

White, H.K. & Levin, E.D. 2004. Psychopharmacology

http://www.eurekalert.org/pub_releases/2003-12/dumc-npm120303.php

Statins associated with rare cases of temporary amnesia

Two recent studies have documented cases of amnesia and other nervous-system side effects after taking statins, the cholesterol-lowering drugs being prescribed to millions of people at risk of heart disease. It is emphasized that this is a rare problem, but given the vast numbers of people taking statins, it might still add up to a significant number of problems.

http://www.eurekalert.org/pub_releases/2003-12/ns-ymw120303.php

False Memories

Older news items (pre-2010) brought over from the old website

Brain wiring creates false memories

We know how easily we can form false memories, but now a new study reveals why some people more easily form these than others. The study had 48 students read lists of semantically related words in which one word which belonged there was absent. They were then asked to recall as many of the words as they could. Those who recalled more of the absent words, and thus assumed to be more prone to false memories, were found to have higher-quality white-matter connections in the superior longitudinal fascicle (which connects frontoparietal structures, and is associated with gist-based learning), while those who were more accurate had higher-quality white-matter connections in the inferior longitudinal fascicle (the major connective pathway of the medial temporal lobe). The findings indicate that individual differences in white matter microstructure underlie true and false memory performance.

Fuentemilla, L. et al. 2009. Individual Differences in True and False Memory Retrieval Are Related to White Matter Brain Microstructure. The Journal of Neuroscience, 29(27), 8698-8703.

http://www.newscientist.com/article/mg20327164.800-brain-wiring-creates-false-memories.html

Eyewitness memory even more vulnerable than expected

We know how easy it is to distort someone’s memory of an event by providing false information, but it’s always been thought that getting people to recall what happened immediately after the event would provide some protection from the misinformation effect. Now a new study has found that those who took a recall test immediately after watching an episode of “24” were in fact more vulnerable to misinformation that was later provided. In fact, they were twice as likely to remember false information that was given after the test compared to those who weren’t given the immediate test. It’s suggested that recently recalled information is particularly vulnerable to distortion.

Chan, J.C.K., Thomas, A.K. & Bulevich, J.B. 2009. Recalling a Witnessed Event Increases Eyewitness Suggestibility: The Reversed Testing Effect. Psychological Science, 20 (1), 66-73.

http://www.physorg.com/news152378697.html
http://www.eurekalert.org/pub_releases/2009-01/afps-dis012809.php

Brain region involved in false memories identified

We’re all susceptible to false memories, but brain damage can produce false memories beyond the normal level. The pathological production of false memories is known as confabulation, and because the patients who suffer this have showed damage to various parts of the brain, the cause has been unclear until now. But a new study of 50 patients has found the common element: all those who confabulated shared damage to the inferior medial prefrontal cortex.

Turner, M.S. et al. 2008. Confabulation: Damage to a specific inferior medial prefrontal system. Cortex, 44 (6), 637-648.

http://www.eurekalert.org/pub_releases/2008-05/e-wym052808.php

Brain waves distinguish false memories from true

An imaging study of 52 neurosurgical patients being treated for drug-resistant epilepsy has found that a fast brain wave, known as the gamma rhythm, increased when participants studied a word that they would later successfully recall. The same gamma waves also increased in the half-second prior to participant’s correctly recalling an item. In other words, the gamma waves predicted whether or not an item that was about to be recalled was previously studied.

Sederberg, P.B. et al. 2007. Gamma Oscillations Distinguish True From False Memories. Psychological Science, 18 (11), 927–932.

http://www.eurekalert.org/pub_releases/2007-10/uop-prp102307.php

Brain activity distinguishes false from true recollection

Although memory confidence and accuracy tend to be positively correlated, people sometimes remember with high confidence events that never happened. A new imaging study reveals that, in cases of high confidence, responses were associated with greater activity in the medial temporal lobe when the event really happened, but with greater activity in the frontoparietal region when the memory was false. Both of these regions are involved in event memory, but the medial temporal lobe focuses on specific facts about the event, while the fronto-parietal network is more likely to process the global gist of the event.

Kim, H. & Cabeza, R. 2007. Trusting Our Memories: Dissociating the Neural Correlates of Confidence in Veridical versus Illusory Memories. Journal of Neuroscience, 27, 12190–12197.

http://www.physorg.com/news113671556.html

Discriminating fact from fiction in recovered memories of childhood sexual abuse

The accuracy of “recovered memories” has long been a contentious issue. A new study has attempted to settle some of the controversy by classifying people who reported being sexually abused as children according to how they remembered the event: “spontaneously recovered” (the participant had forgotten and then spontaneously recalled the abuse outside of therapy, without any prompting), “recovered in therapy” (the participant had recovered the abuse during therapy, prompted by suggestion) or “continuous” (the participant had always been able to recall the abuse). Interviewers who were blind to the type of abuse memory then attempted to confirm or refute the abuse events from outside sources. There were 71 participants who had continuous memory of the event, and 57 participants who had discontinuous memory — of these 41 recalled it spontaneously and 16 in therapy. It was found that spontaneously recovered memories were corroborated about as often (37% of the time) as continuous memories (45%), suggesting that such memories are likely to be just as accurate as memories that have persisted. However, in no case could events that had been ‘recovered’ in therapy be verified. Moreover, evidence that suggestion during therapy possibly brings about these ‘memories’ comes from the finding that individuals who recalled the memories outside therapy were markedly more surprised at the existence of their memories than were individuals who initially recalled the memories in therapy.

Geraerts, E., Schooler, J.W., Merckelbach, D., Jelicic, M., Hauer, B.J.A. & Ambadar, Z. 2007. The Reality of Recovered Memories: Corroborating Continuous and Discontinuous Memories of Childhood Sexual Abuse. Psychological Science, 18 (7), 564–568.

The study is part of an ongoing research project examining recovered memories. For more information, go to www.personeel.unimaas.nl/e.geraerts.

http://www.eurekalert.org/pub_releases/2007-06/afps-sdf061307.php

Virtual reality can improve memory, perhaps too much

A study of virtual marketing strategies has found that people who learned about a camera’s functions through an interactive virtual rendition remembered its functions better than those who learned through text and static pictures. However, they also were more likely to believe it could do things that it couldn't do.

Schlosser, A.E. 2006. Learning Through Virtual Product Experience: The Role of Imagery on True Versus False Memories. Journal of Consumer Research, 33, 377-383.

http://www.eurekalert.org/pub_releases/2006-12/uocp-vrc120506.php

Increasing consumer preferences by manipulating memory

In two experiments, people who had to solve an anagram before seeing a target brand, they were more likely to claim to have seen the brand before, and to prefer it over competing brands.

Kronlund, A. & Bernstein, D.M. 2006. Unscrambling words increases brand name recognition and preference. Applied Cognitive Psychology, 20(5), 681–687.

http://www.eurekalert.org/pub_releases/2006-06/jws-icp062606.php

Older adults more likely to "remember" misinformation

In a study involving older adults (average age 75) and younger adults (average age 19), participants studied lists of paired related words, then viewed new lists of paired words, some the same as before, some different, and some with only one of the two words the same. In those cases, the "prime" word, which was presented immediately prior to the test, was plausible but incorrect. The older adults were 10 times more likely than young adults to accept the wrong word and falsely "remember" earlier studying that word. This was true even though older adults had more time to study the list of word pairs and attained a performance level equal to that of the young adults. Additionally, when told they had the option to "pass" when unsure of an answer, older adults rarely used the option. Younger adults did, greatly reducing their false recall. The findings reflect real-world reports of a rising incidence of scams perpetrated on the elderly, which rely on the victim’s poor memory and vulnerability to the power of suggestion.

Jacoby, L.L., Bishara, A.J., Hessels, S. & Toth, J.P. 2005. Aging, Subjective Experience, and Cognitive Control: Dramatic False Remembering by Older Adults. Journal of Experimental Psychology: General, 134 (2)

http://www.eurekalert.org/pub_releases/2005-05/apa-gmc051005.php

Repeated product warnings are remembered as product recommendations

Warnings about particular products may have quite the opposite effect than intended. Because we retain a familiarity with encountered items far longer than details, the more often we are told a claim about a consumer item is false, the more likely we are to accept it as true a little further down the track. Research also reveals that older adults are more susceptible to this error. It is relevant to note that in the U.S. at least, some 80% of consumer fraud victims are over 65.

Skurnik, I., Yoon, C., Park, D.C. & Schwarz, N. 2005. How Warnings About False Claims Become Recommendations. Journal Of Consumer Research, 31

http://www.eurekalert.org/pub_releases/2005-03/uocp-nrr032905.php

How the brain creates false memories

An imaging study has shed new light on how false memories are formed. The study involved participants watching series of 50 photographic slides that told a story. A little later, the subjects were shown what they thought was the same sequence of slides but in fact containing a misleading item and differing in small ways from the original. Two days later, the subjects’ memories were tested. It was found that, during the original encoding (the 1st set of slides), activity in the hippocampus and perirhinal cortex was greater for true than for false memories, while during the misinformation phase (2nd set), the activity there was greater for false memories. In other regions, such as the prefrontal cortex, activity for false memories tended to be greater during the original event. Activity in the prefrontal cortex may be correlated to encoding the source, or context, of the memory. Thus, weak prefrontal cortex activity during the misinformation phase indicates that the details of the second experience were poorly placed in a learning context, and as a result more easily embedded in the context of the first event, creating false memories.

Okado, Y. & Stark, C.E.L. 2005. Neural activity during encoding predicts false memories created by misinformation. Learning & Memory, 12, 3-11.

http://www.eurekalert.org/pub_releases/2005-02/cshl-htb012805.php

How false memories are formed

An imaging study has attempted to pinpoint how people form a memory for something that didn't actually happen. The study measured brain activity in people who looked at pictures of objects or imagined other objects they were asked to visualize. Three brain areas (precuneus, right inferior parietal cortex and anterior cingulate) showed greater responses in the study phase to words that would later be falsely remembered as having been presented with photos, compared to words that were not later misremembered as having been presented with photos. Brain activity produced in response to viewed pictures also predicted which pictures would be subsequently remembered. Two brain regions in particular -- the left hippocampus and the left prefrontal cortex -- were activated more strongly for pictures that were later remembered than for pictures that were forgotten. The new findings directly showed that different brain areas are critical for accurate memories for visual objects than for false remembering -- for forming a memory for an imagined object that is later remembered as a perceived object.

Gonsalves, B., Reber, P.J., Gitelman, D.R., Parrish, T.B., Mesulam, M-M. & Paller, K.A. 2004. Neural Evidence That Vivid Imagining Can Lead to False Remembering. Psychological Science, 15 (10), 655-660.

http://www.eurekalert.org/pub_releases/2004-10/nu-nrp101404.php

Mood affects eyewitness accuracy and reasoning

A new study suggests people in a negative mood provide more accurate eyewitness accounts than people in a positive mood state. Moreover, people in a positive mood showed poorer judgment and critical thinking skills than those in a negative mood. The researchers suggest that a negative mood state triggers more systematic and attentive, information processing, while good moods signal a benign, non-threatening environment where we don't need to be so vigilant.

The study is to be published in the Journal of Experimental Social Psychology.

http://www.eurekalert.org/pub_releases/2004-08/uons-era082004.php

Stress reactions no guarantee of authenticity

Physical stress reactions have often been taken as evidence for the authenticity of a memory. A recent study investigated people with “memories” of alien abductions (on the grounds that these are the memories least likely to be true) and found that those who believed they had been abducted by aliens responded physically to recall of that memory in the same way as to recall of other, true, stressful events. The finding suggests that a person’s reaction to a memory is no evidence for whether or not it truly happened.

McNally, R.J., Lasko, N.B., Clancy, S.A., Macklin, M.L., Pitman, R.K. & Orr S.P. 2004. Psychophysiological Responding During Script-Driven Imagery in People Reporting Abduction by Space Aliens. Psychological Science, 15 (7), 493-497.

http://www.eurekalert.org/pub_releases/2004-06/aps-ptw062104.php

Stress no aid to memory

Numerous studies have questioned the accuracy of recall of traumatic events, but the research is often dismissed as artificial and not intense enough to simulate real-life trauma. A new study has used real stress: 509 active duty military personnel enrolled in survival school training were deprived of food and sleep 48 hours and then interrogated. A day later, only 30% of those presented with a line-up could identify the right person, only 34% identified their interrogator from a photo-spread and 49% from single photos shown sequentially (putting the interrogator in the same clothing boosted correct identification to 66%). Thirty people even got the gender wrong. Those subjected to physical threats (half the participants) performed worse.

Morgan, C.A.III, Hazlett, G., Doran, A., Garrett, S., Hoyt, G., Thomas, P., Baranoski, M. & Southwick, S.M. 2004. Accuracy of eyewitness memory for persons encountered during exposure to highly intense stress. International Journal of Law and Psychiatry, 27 (3), 265-279.

http://www.newscientist.com/news/news.jsp?id=ns99995089
http://www.eurekalert.org/pub_releases/2004-06/yu-emp060304.php
http://www.eurekalert.org/pub_releases/2004-06/ns-mfy060904.php

Memories of crime stories influenced by racial stereotypes

The influence of stereotypes on memory, a well-established phenomenon, has been demonstrated anew in a study concerning people's memory of news photographs. In the study, 163 college students (of whom 147 were White) examined one of four types of news stories, all about a hypothetical Black man. Two of the stories were not about crime, the third dealt with non-violent crime, while the fourth focused on violent crime. All four stories included an identical photograph of the same man. Afterwards, participants reconstructed the photograph by selecting from a series of facial features presented on a computer screen. It was found that selected features didn’t differ from the actual photograph in the non-crime conditions, but for the crime stories, more pronounced African-American features tended to be selected, particularly so for the story concerning violent crime. Participants appeared largely unaware of their associations of violent crime with the physical characteristics of African-Americans.

Oliver, M.B., Jackson, R.L.II., Moses, N.N. & Dangerfield, C.L. 2004. The Face of Crime: Viewers' Memory of Race-Related Facial Features of Individuals Pictured in the News. Journal of Communication, 54, 88-104.

http://www.eurekalert.org/pub_releases/2004-05/ps-rmo050504.php

Photos facilitate "recovery" of false memories

Another study demonstrating the ease with which people can be persuaded to accept a fabricated childhood memory. A Canadian study found that use of photographs (used by some psychotherapists as memory cues for the "recovery" of patients' possible childhood sexual abuse) resulted in an astounding two-out-of-three participants accepting a concocted false grade-school event as having really happened to them. The study involved 45 first year psychology students being told three stories about their grade-school experiences and asked about their memories of them. Two of the accounts were of real events advised by the participant's parents; the third was fictitious. Participants were encouraged to recall the events through a mix of guided imagery and "mental context re-instatement"--the mental equivalent of putting themselves back in their grade-school shoes. Half of the participants were also given their real grade one class photo. While a quarter or so of the participants without a photo claimed to have some memory of the false event, 67% of those shown a photo claimed some memory.

Lindsay, D.S., Hagen, L., Read, J.D., Wade, K.A. & Garry, M. 2004. True photographs and false memories. Psychological Science, 15, 149-154.
A PDF version of the article can be found at http://web.uvic.ca/psyc/lindsay/cv/index.html#publications

http://www.eurekalert.org/pub_releases/2004-03/nsae-cwb033104.php

Initial steps in a test for false memory

It appears that sensory areas of the brain might be more revealing than the areas specific involved in memory when trying to tell whether a given memory is true or false. An imaging study has found that when people correctly recognised a shape, a visual area called the ventral temporal cortex was more active than when people mistakenly identified a shape that was only similar. In similar vein, auditory regions of the brain became more active during accurate recognition of words.

http://www.newscientist.com/news/news.jsp?id=ns99994363
http://www.eurekalert.org/pub_releases/2003-11/sfn-sfb110803.php

Failing recall not an inevitable consequence of aging

New research suggests age-related cognitive decay may not be inevitable. Tests of 36 adults with an average age of 75 years found that about one out of four had managed to avoid memory decline. Those adults who still had high frontal lobe function had memory skills “every bit as sharp as a group of college students in their early 20s." (But note that most of those older adults who participated were highly educated – some were retired academics). The study also found that this frontal lobe decline so common in older adults is associated with an increased susceptibility to false memories – hence the difficulty often experienced by older people in recalling whether they took a scheduled dose of medication.

The research was presented on August 8 at the American Psychological Association meeting in Toronto.

http://www.eurekalert.org/pub_releases/2003-08/wuis-fmf080703.php

Impact of 'generative learning' on false memories

"Generative learning " refers to the idea that people remember things better when actively involved in forming an idea. For example, if an individual is given a clue and asked to provide a one-word answer, he or she will remember that word better than if simply given the word and told to memorize it. A recent study looked at the effect generative learning might have on the formation of false memories. Participants were given a list of words to memorize – some of the words were complete, and others were missing one letter. Complete and incomplete words came from different subject categories. After the learning period, participants were given a "distracting" math quiz, then presented with a list of words. This list included some words that had not been included in the original list but were related to the subject categories used. It was found that people were far more likely to mistakenly identify a word as one they had seen before, if it was from the same category as the complete words. In another experiment, participants were given a list of words that were missing one letter and could be either of two words, depending on what letter filled in the blank. Some of the participants were given a positive clue, such as "a tennis shoe," and asked to fill in the blank. Others were given a negative clue, such as "not part of a stereo." People were more likely to remember words when given a negative clue than a positive one, and were also less likely to falsely remember a word.

Soraci, S.A., Carlin, M.T., Toglia, M.P., Chechile, R.A. & Neuschatz, J.S. 2003. Generative Processing and False Memories: When There Is No Cost. Journal of Experimental Psychology: Learning, Memory, and Cognition, 29 (4), 511–523.

http://www.eurekalert.org/pub_releases/2003-07/tu-tup072403.php

Remembering imagined actions as real

The latest from Elizabeth Loftus, guru of false memory research. In this study, volunteers performed a variety actions from the commonplace (flipping a coin) to the bizarre (crushing a Hershey's kiss with a dental floss container). Later, they were asked to imagine additional actions, such as kissing a frog. At a future time, participants were asked to recall their actions on that specific day. It was found that 15% of the volunteers claimed they had actually performed some of the actions they had only imagined.

The research was reported at the "Remembering Traumatic Experiences in Childhood: Reliability and Limitations of Memory" symposium at the American Association for the Advancement of Science Annual Meeting in Denver, on February 16.

http://www.eurekalert.org/pub_releases/2003-02/uoc--fkf021303.php

Hypnosis may give false confidence in inaccurate memories

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. Joseph Green, co-author of the study and associate professor of psychology at Ohio State University's Lima campus, said the results of the new study don't mean that hypnosis has no value. Any kind of technique used to retrieve memories - including the use of diaries or drugs - will produce inaccurate memories. However, the difference is that people tend to have more faith in hypnosis than they do in other memory techniques.

Green, J. & Lynn, S.J. (2001). a paper presented Aug. 26 in San Francisco at the annual meeting of the American Psychological Association (hypnotism).The results of this study were presented in San Francisco at the annual meeting of the American Psychological Association on August 26.

http://www.eurekalert.org/pub_releases/2001-08/osu-hmg082201.php

New evidence shows how easily false memories can be created

About one-third of the people who were exposed to a fake print advertisement that described a visit to Disneyland and how they met and shook hands with Bugs Bunny later said they remembered or knew the event happened to them.

The study was presented the annual meeting of the American Psychological Society on June 17 in Toronto and at a satellite session of the Society for Applied Research in Memory and Cognition in Kingston, Ontario.

http://www.eurekalert.org/pub_releases/2001-06/UoW-tIta-1006101.php

Magnetic resonance imaging reveals difference between true and false memories

Tests of the human capacity for believing false memories have typically involved giving subjects a list of associated words and then testing their memory for these words by offering a new list which includes not only the previous words but also related words that were not presented earlier. A strong tendency to falsely recognize such words is characteristically found, but intriguingly, the subjects also tend to rate true items higher than false items in terms of sensory details. This suggests that, although people truly believe their false memories, part of the brain at least, recognizes that they are not as "real" as true memories. This has been something of a conundrum in false memory research.
A recent study used magnetic resonance imaging to monitor brain activity during such testing. The memory experience was made richer by having the words read on video by alternating male and female speakers. The findings were the same as in previous studies - subjects rejected new words, but falsely recognized false words related to the true words. The brain scans revealed that different parts of the brain processed true and false memories differently. The region that processes perceptual information, such as the speaker appearance and voice, was more activated for true memories.

Cabeza, R., Rao, S.M., Wagner, A.D., Mayer, A.R. & Schacter, D.L. 2001. Can medial temporal lobe regions distinguish true from false? An event-related functional MRI study of veridical and illusory recognition memory. Proc. Natl. Acad. Sci. USA, 98 (8), 4805-4810.

http://www.eurekalert.org/pub_releases/2001-05/DU-Rhun-0305101.php

 

tags problems: 

Pages

Subscribe to RSS - Problems