Older news items (pre-2010) brought over from the old website
Aerobic fitness boosts IQ in teenage boys
Data from the 1.2 million Swedish men born between 1950 and 1976 who enlisted for mandatory military service at the age of 18 has revealed that on every measure of cognitive performance, average test scores increased according to aerobic fitness — but not muscle strength. The link was strongest for logical thinking and verbal comprehension, and the association was restricted to cardiovascular fitness. The results of the study also underline the importance of getting healthier between the ages of 15 and 18 while the brain is still changing — those who improved their cardiovascular health between 15 and 18 showed significantly greater intelligence scores than those who became less healthy over the same time period. Those who were fittest at 18 were also more likely to go to college. Although association doesn’t prove cause, the fact that the association was only with cardiovascular fitness and not strength supports a cardiovascular effect on brain function. Results from over 260,000 full-sibling pairs, over 3,000 sets of twins, and more than 1,400 sets of identical twins, also supports a causal relationship.
[1486] Åberg, M AI., Pedersen N. L., Torén K., Svartengren M., Bäckstrand B., Johnsson T., et al.
(2009). Cardiovascular fitness is associated with cognition in young adulthood.
Proceedings of the National Academy of Sciences. 106(49), 20906 - 20911.
http://www.physorg.com/news179415275.html
http://www.telegraph.co.uk/science/science-news/6692474/Physical-health-leads-to-mental-health.html
Confidence as important as IQ in exam success
I’ve talked repeatedly about the effects of self-belief on memory and cognition. One important area in which this is true is that of academic achievement. Evidence indicates that your perceived abilities matter, just as much? more than? your actual abilities. It has been assumed that self perceived abilities, self-confidence if you will, is a product mainly of nurture. Now a new twin study provides evidence that nurture / environment may only provide half the story; the other half may lie in the genes. The study involved 1966 pairs of identical twins and 1877 pairs of fraternal twins. The next step is to tease out which of these genes are related to IQ and which to personality variables.
[1080] Greven, C. U., Harlaar N., Kovas Y., Chamorro-Premuzic T., & Plomin R.
(2009). More Than Just IQ: School Achievement Is Predicted by Self-Perceived Abilities—But for Genetic Rather Than Environmental Reasons.
Psychological Science. 20(6), 753 - 762.
http://www.newscientist.com/article/dn17187-confidence-as-important-as-iq-in-exam-success.html
Children of older fathers perform less well in intelligence tests during infancy
Reanalysis of a dataset of over 33,000 children born between 1959 and 1965 and tested at 8 months, 4 years, and 7 years, has revealed that the older the father, the more likely the child was to have lower scores on the various tests used to measure the ability to think and reason, including concentration, learning, memory, speaking and reading skills. In contrast, the older the mother, the higher the scores of the child in the cognitive tests.
[1447] Saha, S., Barnett A. G., Foldi C., Burne T. H., Eyles D. W., Buka S. L., et al.
(2009). Advanced Paternal Age Is Associated with Impaired Neurocognitive Outcomes during Infancy and Childhood.
PLoS Med. 6(3), e1000040 - e1000040.
Full text available at http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pmed.1000040
http://www.eurekalert.org/pub_releases/2009-03/plos-coo030309.php
Brain-training to improve working memory boosts fluid intelligence
General intelligence is often separated into "fluid" and "crystalline" components, of which fluid intelligence is considered more reflective of “pure” intelligence (for more on this, see my article), and largely resistant to training and learning effects. However, in a new study in which participants were given a series of training exercises designed to improve their working memory, fluid intelligence was found to have significantly improved, with the amount of improvement increasing with time spent training. The small study contradicts decades of research showing that improving on one kind of cognitive task does not improve performance on other kinds, so has been regarded with some skepticism by other researchers. More research is definitely needed, but the memory task did differ from previous studies, engaging executive functions such as those that inhibit irrelevant items, monitor performance, manage two tasks simultaneously, and update memory.
[1183] Jaeggi, S. M., Buschkuehl M., Jonides J., & Perrig W. J.
(2008). From the Cover: Improving fluid intelligence with training on working memory.
Proceedings of the National Academy of Sciences. 105(19), 6829 - 6833.
http://www.physorg.com/news128699895.html
http://www.sciam.com/article.cfm?id=study-shows-brain-power-can-be-bolstered
Effect of schooling on achievement gaps within racial groups
Analysis of data from a national sample (U.S.) of 8,060 students, collected at four points in time, starting in kindergarten and ending in the spring of fifth grade, has found evidence that education has an impact in closing the achievement gap for substantial numbers of children. High-performing groups in reading were found among all races. About 30% of European Americans, 26% of African Americans and 45% of Asian Americans were in high-achieving groups by the spring of fifth grade — these groups included approximately 23% of African American children and 36% of Asian children who caught up with the initial group of high achievers over time. Only around 4% of European American students were in catch-up groups, because a higher percentage of European Americans started kindergarten as high achievers in reading. The situation was different for Hispanic students, however. By the end of fifth grade, just over 5% of Hispanic children were high achievers in reading, while the remainder tested in the middle range. There were no low achievers and no catch-up groups. A different pattern was found in math. Only 17% of European American students were high-achievers in math by the end of fifth grade, including 13% who started kindergarten at a lower achievement level and caught up over time. About 18% of Asian Americans were high-achievers at the end of fifth grade (11% catch-up). Only 0.3% of African Americans were high achievers at the end of fifth grade, and 26% were medium-high achievers. But about 16% of Hispanics were high achievers in math. There were no catch-up groups for either the African Americans or the Hispanics. This suggests that current schooling doesn't have as strong an impact on math achievement as it does in reading.
The study was presented in Washington, D.C. at the 2008 annual meeting of the Society for Research on Educational Effectiveness.
http://www.physorg.com/news123859991.html
Autism non-verbal not unintelligent
New findings suggest that the association of autism with low intelligence is a product of their language difficulties. Testing autistic kids and normal kids on two popular IQ tests — the WISC (which relies heavily on language) and Raven's Progressive Matrices (considered the best test of "fluid intelligence", and a test that doesn't require much language) found that while not a single autistic child scored in the "high intelligence" range of the WISC, a third did on the Raven's. A third of the autistics had WISC scores in the mentally retarded range, but only one in 20 scored that low on the Raven's test. The non-autistic children scored similarly on both tests. The same results occurred when the experiment was run on autistic and normal adults.
[580] Dawson, M., Soulières I., Gernsbacher M A., & Mottron L.
(2007). The level and nature of autistic intelligence.
Psychological Science: A Journal of the American Psychological Society / APS. 18(8), 657 - 662.
http://www.physorg.com/news105376203.html
http://www.eurekalert.org/pub_releases/2007-08/afps-tmo080307.php
Being treated as oldest linked to IQ
The question of whether there is an IQ advantage to being the first-born has long been debated. Now analysis of IQ test results of 241,310 Norwegians drafted into the armed forces between 1967 and 1976 has revealed that the average IQ of first-born men was 103.2 while second-born men averaged 101.2 and third-borns, 100.0. However, second-born men whose older sibling died in infancy scored 102.9, and if both older siblings died young, the third-born score rose to 102.6. This suggests the advantage lies in the social rank in the family and not birth order as such.
[589] Kristensen, P., & Bjerkedal T.
(2007). Explaining the Relation Between Birth Order and Intelligence.
Science. 316(5832), 1717 - 1717.
http://www.nature.com/news/2007/070618/full/070618-14.html
Executive function as important as IQ for math success
A study of 141 preschoolers from low-income homes has found that a child whose IQ and executive functioning were both above average was three times more likely to succeed in math than a child who simply had a high IQ. The parts of executive function that appear to be particularly linked to math ability in preschoolers are working memory and inhibitory control. In this context, working memory may be thought of as the ability to keep information or rules in mind while performing mental tasks. Inhibitory control is the ability to halt automatic impulses and focus on the problem at hand. Inhibitory control was also important for reading ability. The finding offers the hope that training to improve executive function will improve academic performance.
[1256] Blair, C., & Razza R P.
(2007). Relating Effortful Control, Executive Function, and False Belief Understanding to Emerging Math and Literacy Ability in Kindergarten.
Child Development. 78(2), 647 - 663.
http://www.sciam.com/article.cfm?articleID=90377FAE-E7F2-99DF-3A1204FC5F2BF0F7
Students who believe intelligence can be developed perform better
Research with 12-year-olds has found that, although all students began the study with equivalent achievement levels in math, over a two year period, those who believed that intelligence was malleable increasingly did better than those who believed their intelligence was fixed. Another study found that, when students showing declines in their math grades were taught that intelligence could be increased, they reversed their decline and showed significantly higher math grades than others who weren’t taught that.
[1123] Blackwell, L. S., Trzesniewski K. H., & Dweck C S.
(2007). Implicit Theories of Intelligence Predict Achievement across an Adolescent Transition: A Longitudinal Study and an Intervention.
Child Development. 78(1), 246 - 263.
http://www.eurekalert.org/pub_releases/2007-02/sfri-swb013107.php
Implicit stereotypes and gender identification may affect female math performance
Relatedly, 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.
Fitness and childhood IQ indicators of cognitive ability in old age
Data from the Scottish Mental Survey of 1932 has revealed that physical fitness contributed more than 3% of the differences in cognitive ability in old age. The study involved 460 men and women, who were tested using the same cognitive test at age 79 that they had undergone at age 11. Physical fitness was defined by time to walk six meters, grip strength and lung function. Childhood IQ was also significantly related to lung function at age 79, perhaps because people with higher intelligence might respond more favorably to health messages about staying fit. But physical fitness was more important for cognitive ability in old age than childhood IQ. People in more professional occupations and with more education also had better fitness and higher cognitive test scores at 79.
[770] Deary, I. J., Whalley L. J., Batty D. G., & Starr J. M.
(2006). Physical fitness and lifetime cognitive change.
Neurology. 67(7), 1195 - 1200.
http://www.eurekalert.org/pub_releases/2006-10/aaon-fac100306.php
Black-white IQ gap has narrowed
Data now available suggests that Black Americans have gained an average of .18 IQ points a year on White Americans from 1972 to 2002 for a total gain of 5.4 IQ points.
[929] Dickens, W. T., & Flynn J. R.
(2006). Black Americans reduce the racial IQ gap: evidence from standardization samples.
Psychological Science: A Journal of the American Psychological Society / APS. 17(10), 913 - 920.
http://www.eurekalert.org/pub_releases/2006-09/afps-big091206.php
Does IQ drop with age or does something else impact intelligence?
As people grow older, their IQ scores drop. But is it really that they lose intelligence? A study has found that if college students had to perform under conditions that mimic the perception deficits many older people have, their IQ scores would also take a drop.
[234] Gilmore, G. C., Spinks R. A., & Thomas C. W.
(2006). Age effects in coding tasks: componential analysis and test of the sensory deficit hypothesis.
Psychology and Aging. 21(1), 7 - 18.
http://www.eurekalert.org/pub_releases/2006-05/cwru-did050106.php
Smarter kids may live longer
A prospective study that recruited 897 individuals who scored 135 or higher on the Stanford-Binet IQ test in 1922 has found that higher IQs were associated with longevity, with the survival advantage leveling off after a childhood IQ of 163. The association was independent of childhood social position (as measured by father’s occupation). The study confirms earlier research suggesting an association between IQ and mortality, and provides the new finding of where the cut-off point (when high IQ no longer brought additional health benefits) appears — the cutoff of 163 was much higher than expected. Suggested reasons for the association (all of which may well be valid) include: greater tendency to adopt healthy habits and avoid bad ones; increased probability of better jobs; better skills for managing their health and the health-care system.
[690] Martin, L. T., & Kubzansky L. D.
(2005). Childhood Cognitive Performance and Risk of Mortality: A Prospective Cohort Study of Gifted Individuals.
Am. J. Epidemiol.. 162(9), 887 - 890.
http://health.yahoo.com/news/126478
Growing up in a chaotic home may impair child's cognitive development
An association between disorganized, noisy and cramped homes and lower childhood intelligence has been observed before, but the reasons for the association have never been clear. Now a study of some 8000 3- and 4-year-old twins has perhaps disentangled the variables, and has found that chaos had an influence on cognitive skills independent of socioeconomic status. The findings also suggest that when the environment is more stressful, intelligence is more likely to be constrained by genes.
[570] Petrill, S. A., Pike A., Price T., & Plomin R.
(Submitted). Chaos in the home and socioeconomic status are associated with cognitive development in early childhood: Environmental mediators identified in a genetic design.
Intelligence. 32(5), 445 - 460.
http://www.newscientist.com/news/news.jsp?id=ns99996323
Early music instruction raises child’s IQ
A new study confirms earlier research supporting the benefits of early music instruction. The study involved 144 children, 6 years old at the start of the study. They were given free weekly voice or piano lessons at the Royal Conservatory of Music. Another group of 6-year-olds was given free training in weekly drama classes, while a fourth group received no extra classes during the study period. Before any classes were given, all the children were tested using the full Weschler intelligence test. At the end of the school year (their first school year), the children were retested. All had an IQ increase of at least 4.3 points on average (a consequence of going to school). Children who took drama lessons scored no higher than those who had no extra lessons, but those who took music lessons scored on average 2.7 points higher than the children who did not take music lessons. Those in the drama group did however show substantial improvement in adaptive social behavior.
[1009] Schellenberg, E. Glenn
(2004). Music lessons enhance IQ.
Psychological Science: A Journal of the American Psychological Society / APS. 15(8), 511 - 514.
http://www.sciencentral.com/articles/view.htm3?article_id=218392326
Knowledge-based IQ test predicts work performance as well as school
A meta-analysis of 127 studies supports the view that the Miller Analogies Test (MAT) — a knowledge-based test used for admissions decisions into U.S. graduate schools as well as in hiring and promotion decisions in the workplace since 1926 — is predictive of performance in both the academic and workplace environments. Specifically, MAT was a valid predictor of seven of the eight measures of graduate student performance, five of the six school-to-work transition performance criteria, and all four of the work performance criteria. MAT is assumed to measure “g”, the oft-debated “general intelligence” factor.
[1109] Kuncel, N. R., Hezlett S. A., & Ones D. S.
(2004). Academic Performance, Career Potential, Creativity, and Job Performance: Can One Construct Predict Them All?.
Journal of Personality and Social Psychology. 86(1), 148 - 161.
Support for "general intelligence" factor
Researchers into intelligence and memory have always concentrated on verbal abilities — for the good reason that they are considerably easier to test. New research suggests that strong visuospatial skills and working memory may be at least as good as verbal skills and working memory as indicators of general intelligence. The study, involving 167 subjects, found a clear relationship between being good at complex visuospatial tasks, and being good at tasks involving the so-called “central executive” (which coordinates tasks, sets goals, etc). The study lends support both to the view that intelligence has both discrete components and a general aspect, and that this “general intelligence” may be related to executive functioning.
[1152] Miyake, A., Friedman N. P., Rettinger D. A., Shah P., & Hegarty M.
(2001). How are visuospatial working memory, executive functioning, and spatial abilities related? A latent-variable analysis.
Journal of Experimental Psychology. General. 130(4), 621 - 640.
http://www.eurekalert.org/pub_releases/2001-12/apa-npo121001.php