Older news items (pre-2010) brought over from the old website
Binge drinking affects attention and working memory in young university students
A Spanish study of 95 first-year university students, 42 of them binge drinkers, has found that those who engaged in binge drinking required greater attentional processing during a visual working memory task in order to carry it out correctly. They also had difficulties differentiating between relevant and irrelevant stimuli. Binge drinkers are defined as males who drink five or more standard alcohol drinks, and females who drink four or more, on one occasion and within a two-hour interval. Some 40% of university students in the U.S. are considered binge drinkers.
[231] Crego, A., Holguín S R., Parada M., Mota N., Corral M., & Cadaveira F.
(2009). Binge drinking affects attentional and visual working memory processing in young university students.
Alcoholism, Clinical and Experimental Research. 33(11), 1870 - 1879.
http://www.eurekalert.org/pub_releases/2009-08/ace-bda080509.php
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
When emotions involved, older adults may perform memory tasks better than young adults
A study involving 72 young adults (20-30 years old) and 72 older adults (60-75) has found that regulating emotions – such as reducing negative emotions or inhibiting unwanted thoughts – is a resource-demanding process that disrupts the ability of young adults to simultaneously or subsequently perform tasks, but doesn’t affect older adults. In the study, most of the participants watched a two-minute video designed to induce disgust, while the rest watched a neutral two-minute clip. Participants then played a computer memory game. Before playing 2 further memory games, those who had watched the disgusting video were instructed either to change their negative reaction into positive feelings as quickly as possible or to maintain the intensity of their negative reaction, or given no instructions. Those young adults who had been told to turn their disgust into positive feelings, performed significantly worse on the subsequent memory tasks, but older adults were not affected. The feelings of disgust in themselves did not affect performance in either group. It’s speculated that older adults’ greater experience allows them to regulate their emotions without cognitive effort.
[200] Scheibe, S., & Blanchard-Fields F.
(2009). Effects of regulating emotions on cognitive performance: what is costly for young adults is not so costly for older adults.
Psychology and Aging. 24(1), 217 - 223.
http://www.eurekalert.org/pub_releases/2009-03/giot-oac030409.php
Inconsistent processing speed among children with ADHD
A new analytical technique has revealed that the problem with children with ADHD is not so much that they are slower at responding to tasks, but rather that their response is inconsistent. The study of 25 children with ADHD and 24 typically developing peers found that on a task in which a number on one screen needed to be mentally added to another number shown on a second screen, those with ADHD were much less consistent in their response times, although the responses they did give were just as accurate. Higher levels of hyperactivity and restlessness or impulsivity (as measured by parent survey) correlated with more slower reaction times. The finding supports the idea that what underlies impaired working memory is a problem in how consistently a child with ADHD can respond during a working memory task.
[911] Buzy, W. M., Medoff D. R., & Schweitzer J. B.
(2009). Intra-Individual Variability Among Children with ADHD - on a Working Memory Task: An Ex-Gaussian Approach.
Child Neuropsychology. 15(5), 441 - 441.
http://www.eurekalert.org/pub_releases/2009-03/uoc--ips032409.php
Hyperactivity enables children with ADHD to stay alert
A study of 12 8- to 12-year-old boys with ADHD, and 11 of those without, has found that activity levels of those with ADHD increased significantly whenever they had to perform a task that placed demands on their working memory. In a highly stimulating environment where little working memory is required (such as watching a Star Wars video), those with ADHD kept just as still as their normal peers. It’s suggested that movement helps them stay alert enough to complete challenging tasks, and therefore trying to limit their activity (when non-destructive) is counterproductive. Providing written instructions, simplifying multi-step directions, and using poster checklists are all strategies that can be used to help children with ADHD learn without overwhelming their working memories.
[734] Rapport, M., Bolden J., Kofler M., Sarver D., Raiker J., & Alderson R.
(2009). Hyperactivity in Boys with Attention-Deficit/Hyperactivity Disorder (ADHD): A Ubiquitous Core Symptom or Manifestation of Working Memory Deficits?.
Journal of Abnormal Child Psychology. 37(4), 521 - 534.
http://www.eurekalert.org/pub_releases/2009-03/uocf-ush030909.php
Poverty can physically impair brain, reducing children's ability to learn
We know that stress affects learning and memory, and there is considerable evidence confirming the commonsense intuition that low-income families are under a lot of stress. Now a long-term study involving 195 children from rural households above and below the poverty line has found that children who lived in impoverished environments for longer periods of time during childhood showed higher stress scores and suffered greater impairments in working memory at 17. Those who spent their entire childhood in poverty scored about 20% lower on working memory tests at 17 than those who were never poor.
[461] Evans, G. W., & Schamberg M. A.
(2009). Childhood poverty, chronic stress, and adult working memory.
Proceedings of the National Academy of Sciences. 106(16), 6545 - 6549.
Full text available at http://www.pnas.org/content/early/2009/03/27/0811910106.abstract?sid=b4c74b57-a4a5-447b-8675-ba75e69f3ec2
http://www.physorg.com/news158594009.html
http://www.washingtonpost.com/wp-dyn/content/article/2009/04/05/AR2009040501719.html
New research shows why too much memory may be a bad thing
People who are able to easily and accurately recall historical dates or long-ago events may have a harder time with word recall or remembering the day's current events. A mouse study reveals why. Neurogenesis has been thought of as a wholly good thing — having more neurons is surely a good thing — but now a mouse study has found that stopping neurogenesis in the hippocampus improved working memory. Working memory is highly sensitive to interference from information previously stored in memory, so it may be that having too much information may hinder performing everyday working memory tasks.
[635] Saxe, M. D., Malleret G., Vronskaya S., Mendez I., Garcia D. A., Sofroniew M. V., et al.
(2007). Paradoxical influence of hippocampal neurogenesis on working memory.
Proceedings of the National Academy of Sciences. 104(11), 4642 - 4646.
Full text is available at http://www.pnas.org/cgi/reprint/104/11/4642
http://www.physorg.com/news94384934.html
http://www.sciencedaily.com/releases/2007/03/070329092022.htm
http://www.eurekalert.org/pub_releases/2007-03/cumc-nrs032807.php
Implicit stereotypes and gender identification may affect female math performance
Another study has come out showing that women enrolled in an introductory calculus course who possessed strong implicit gender stereotypes, (for example, automatically associating "male" more than "female" with math ability and math professions) and were likely to identify themselves as feminine, performed worse relative to their female counterparts who did not possess such stereotypes and who were less likely to identify with traditionally female characteristics. Strikingly, a majority of the women participating in the study explicitly expressed disagreement with the idea that men have superior math ability, suggesting that even when consciously disavowing stereotypes, female math students are still susceptible to negative perceptions of their ability.
[969] Kiefer, A. K., & Sekaquaptewa D.
(2007). Implicit stereotypes, gender identification, and math-related outcomes: a prospective study of female college students.
Psychological Science: A Journal of the American Psychological Society / APS. 18(1), 13 - 18.
http://www.eurekalert.org/pub_releases/2007-01/afps-isa012407.php
Reducing the racial achievement gap
And staying with the same theme, a study that came out six months ago, and recently reviewed on the excellent new Scientific American Mind Matters blog, revealed that a single, 15-minute intervention erased almost half the racial achievement gap between African American and white students. The intervention involved writing a brief paragraph about which value, from a list of values, was most important to them and why. The intervention improved subsequent academic performance for some 70% of the African American students, but none of the Caucasians. The study was repeated the following year with the same results. It is thought that the effect of the intervention was to protect against the negative stereotypes regarding the intelligence and academic capabilities of African Americans.
[1082] Cohen, G. L., Garcia J., Apfel N., & Master A.
(2006). Reducing the Racial Achievement Gap: A Social-Psychological Intervention.
Science. 313(5791), 1307 - 1310.
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
Common gene version optimizes thinking but carries a risk
On the same subject, another study has found that the most common version of DARPP-32, a gene that shapes and controls a circuit between the striatum and prefrontal cortex, optimizes information filtering by the prefrontal cortex, thus improving working memory capacity and executive control (and thus, intelligence). However, the same version was also more prevalent among people who developed schizophrenia, suggesting that a beneficial gene variant may translate into a disadvantage if the prefrontal cortex is impaired. In other words, one of the things that make humans more intelligent as a species may also make us more vulnerable to schizophrenia.
[864] Kolachana, B., Kleinman J. E., Weinberger D. R., Meyer-Lindenberg A., Straub R. E., Lipska B. K., et al.
(2007). Genetic evidence implicating DARPP-32 in human frontostriatal structure, function, and cognition.
Journal of Clinical Investigation. 117(3), 672 - 682.
http://www.sciencedaily.com/releases/2007/02/070208230059.htm
http://www.eurekalert.org/pub_releases/2007-02/niom-cgv020707.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
Memory-enhancing drugs for elderly may impair working memory and other executive functions
Drugs that increase the activity of an enzyme called protein kinase A improve long-term memory in aged mice and have been proposed as memory-enhancing drugs for elderly humans. However, the type of memory improved by this activity occurs principally in the hippocampus. A new study suggests that increased activity of this enzyme has a deleterious effect on working memory (which principally involves the prefrontal cortex). In other words, a drug that helps you remember a recent event may worsen your ability to remember what you’re about to do (to take an example).
[1404] Ramos, B. P., Birnbaum S. G., Lindenmayer I., Newton S. S., Duman R. S., & Arnsten A. F. T.
(2003). Dysregulation of protein kinase a signaling in the aged prefrontal cortex: new strategy for treating age-related cognitive decline.
Neuron. 40(4), 835 - 845.
http://www.eurekalert.org/pub_releases/2003-11/naos-mdf110303.php
Sleep deprivation affects working memory
A recent study investigated the working memory capacities of individuals who were sleep-deprived. For nine days, 7 of the 12 participants slept four hours each night, and 5 slept for eight hours. Each morning, participants completed a computer task to measure how quickly they could access a list of numbers they had been asked to memorize. The list could be one, three, or five items long. Then participants were presented with a series of single digits and asked to answer "yes" or "no" to indicate whether each digit was one they had memorized. Those who slept eight hours a night steadily increased their working memory efficiency on this task, but those who slept only four hours a night failed to show any improvement in memory efficiency. Motor skill did not change across days for either group of participants.
The findings were presented at the Society for Neuroscience 2003 annual conference.
http://www.eurekalert.org/pub_releases/2003-11/sfn-sfb_1111003.php
Cognitive impairment following bypass surgery may last longer than thought
More support for a link between cardiopulmonary bypass surgery and cognitive impairment comes from a new study. In particular, it seems, that attention may be most affected. The study also found evidence of longer-lasting cognitive decline than previously thought. Bypass patients also demonstrated poorer cognitive performance before the surgery, and it is now being suggested that it may be the disease itself that is the major problem, rather than the surgery itself. This is consistent with recent research connecting cardiovascular risk factors with risk factors for cognitive decline.
[716] Keith, J. R., Puente A. E., Malcolmson K. L., Tartt S., Coleman A. E., & Marks H. F.
(2002). Assessing postoperative cognitive change after cardiopulmonary bypass surgery.
Neuropsychology. 16(3), 411 - 421.
http://www.eurekalert.org/pub_releases/2002-07/apa-lci070802.php
Cocaine may permanently damage learning abilities in developing fetuses
Two recent studies investigating the effect of pre-natal exposure to cocaine in rats suggest that children exposed to cocaine while in the womb may have permanent changes to the part of the brain that helps control attention and memory, leading to learning deficits and symptoms that are very much like attention deficit hyperactivity disorder.
[1270] Morrow, B. A., Elsworth J. D., & Roth R. H.
(2002). Male rats exposed to cocaine in utero demonstrate elevated expression of Fos in the prefrontal cortex in response to environment.
Neuropsychopharmacology: Official Publication of the American College of Neuropsychopharmacology. 26(3), 275 - 285.
[264] Morrow, B. A., Elsworth J. D., & Roth R. H.
(2002). Prenatal cocaine exposure disrupts non-spatial, short-term memory in adolescent and adult male rats.
Behavioural Brain Research. 129(1-2), 217 - 223.
http://www.eurekalert.org/pub_releases/2002-02/yu-ucd021802.php