Sex differences in intelligence
|This article relies too much on references to primary sources. (July 2014)|
|This article is one of a series on:|
|Sex differences in humans|
Differences in intelligence have long been a topic of debate among researchers and scholars. With the advent of the concept of g or general intelligence, many researchers demonstrated no significant sex differences in g factor or general intelligence while others arguing greater intelligence for males. The split view between these researchers depended on the methodology and tests they used for their claims. One study did find some advantage for women in later life, while another found that male advantages on some cognitive tests are minimized when controlling for socioeconomic factors.
Some studies have concluded that there is larger variability in male scores compared to female scores, which results in more males than females in the top and bottom of the IQ distribution. This remains a controversial claim.
There are, however, differences in the capacity of males and females in performing certain tasks, such as rotation of object in space, often categorized as spatial ability.
- 1 Historical perspectives
- 2 Current research on general intelligence
- 3 Brain and intelligence
- 4 Mathematics performance
- 5 Spatial ability
- 6 Sex differences in academics
- 7 Dyslexia
- 8 See also
- 9 References
Prior to the 20th century, it was a commonly held view that men were intellectually superior to women. Thomas Gisborne argued (1801) that women were naturally suited to domestic work and not spheres suited to men such as politics, science, or business. He argued that this was because women did not possess the same level of rational thinking that men did and had naturally superior abilities in skills related to family support.
In 1875, Herbert Spencer argued that women were incapable of abstract thought and could not understand issues of justice, and only had the ability to understand issues of care. In 1925, Sigmund Freud also concluded that women were less morally developed in the concept of justice, and, unlike men, were more influenced by feeling than rational thought. Early brain studies comparing mass and volumes between the sexes concluded that women were intellectually inferior because they had smaller and lighter brains. Many believed that the size difference caused women to be excitable, emotional, sensitive, and therefore not suited for political participation.
In the nineteenth century, whether men and women had equal intelligence was seen by many as a prerequisite for the granting of suffrage. Leta Hollingworth argues that women were not permitted to realize their full potential, as they were confined to the roles of child-rearing and housekeeping.
During the early twentieth century, the scientific consensus shifted to the view that gender plays no role in intelligence. In his 1916 study of children's IQs, psychologist Lewis Terman concluded that "the intelligence of girls, at least up to 14 years, does not differ materially from that of boys". He did, however, find "rather marked" differences on a minority of tests. For example, he found boys were "decidedly better" in arithmetical reasoning, while girls were "superior" at answering comprehension questions. He also proposed that discrimination, lack of opportunity, women's responsibilities in motherhood, or emotional factors may have accounted for the fact that few women had careers in intellectual fields.
Current research on general intelligence
According to the 1994 report "Intelligence: Knowns and Unknowns" by the American Psychological Association, "Most standard tests of intelligence have been constructed so that there are no overall score differences between females and males." However, differential item functioning does not mean that researchers get rid of group differences due to ability differences, but certain questions are removed due to item bias when participants from different groups perform differently even though they have the same latent ability. Differences have been found, however, in specific areas such as mathematics and verbal measures.
When standardized IQ tests were first developed in the early 20th century, girls typically scored higher than boys until age 14, at which time the curve for girls dropped below that for boys. As testing methodology was revised, efforts were made to equalize gender performance.
The mean IQ scores between men and women vary little. The variability of male scores is greater than that of females, however, resulting in more males than females in the top and bottom of the IQ distribution.
Researchers in favor of males in g factor
At one time it was overwhelming consensus that there were no sex differences in g factor or general intelligence. However, researcher Richard Lynn challenged this consensus on two arguments: 1) Males have bigger brain size in proportion to their body, and 2) there are little or no sex differences up until the age of 16 because males have slower developmental maturation. A 2004 meta-analysis by Richard Lynn and Paul Irwing published in 2005 found mean IQ of men exceeding that of women by a range of 5 points on the Raven's Progressive Matrices test. Lynn's findings were debated in a series of articles for Nature. Jackson and Philipe Rushton found males aged 17–18 years had average of 3.63 IQ points in excess of their female equivalents on the Scholastic Assessment Test. Irwing (2012) found a 3 point IQ advantage for males in g from subjects aged 16–89 in the United States on the WAIS III test favouring men on the information, arithmetic and symbol search and favoring women on the processing speed A 2005 study by Ian Deary, Paul Irwing, Geoff Der, and Timothy Bates, focusing on the ASVAB showed a significantly higher variance in male scores, resulting in more than twice as many men as women scoring in the top 2%. The study also found a very small (d' ≈ 0.07, less than 7%, of a standard deviation) average male advantage in g on the Armed Services Vocational Aptitude Battery test . Another study with Richard Lynn conducted in Sudan found 16-18 year old males scored 5 points higher on the Raven's Progressive Matrices. Another study by researcher Jianghong Liu found also found 3 points higher male scores on the WISC which is the children version of the WAIS III. He explained that greater male performance on items such as Picture Arrangement, Object Assembly, Picture Completion and Block Design are because they measure visual–spatial abilities in which males typically perform better than females.
Researchers in favor of no sex differences or inconclusive consensus
In 2000, researchers Roberto Colom and Francisco J. Abado conducted a large study of 10,475 adults on five IQ tests taken from the Primary Mental Abilities and found negligible or no significant sex differences. The tests conducted were on vocabulary, spatial rotation, verbal fluency, inductive reasoning and Monedas. Roberto Colom in 2002 found 3.16 higher IQ points for males on the WAIS III test but no difference on the general intelligence factor (g) and therefore explained the differences as due to non-g factors such as specific group factors and test specificity. Responding to findings by Richard Lynn in 2002, researchers Roberto Colom and Oscar Garcia Lopez proposed that g factor is the variance of correlation among different IQ tests and not the sum of group scores published by Richard Lynn in his studies. So measuring variance of Colom's study of 4,072 high school graduates, they found females outperform males on the inductive Primary Mental Abilities reasoning test, males outperform females on the Raven's Progressive matrices and there is no difference on the Culture-Fair Intelligence test and therefore concluded no difference in general intelligence. Using multi-group covariance and mean group structure analysis in 2006, researchers Sophie van der Sluis, Conor V Dolan and Roberto Colom found that g factor couldn't explain any sex differences on the WAIS III. Later that year in another study, the same researchers concluded that sex differences on WAIS are due to primary factors or broad stratum abilities like working memory and perceptual organization not g factor. (See CHC theory)A study conducted by Jim Flynn and Lilia Rossi-Case (2011) found that men and women achieved roughly equal IQ scores on Raven's Progressive Matrices after reviewing recent standardization samples in five modernized nations. In 2010, researcher Emily Savage-McGlynn proposed that inconsistent results in sex differences is due to opportunity samples rather than samples that represent the general population. After a study with nationally representative sample of 926 participants in the UK, no sex difference was found in the Raven's Progressive Matrices test.
Aside from traditional IQ tests like Raven's and WAIS, researchers have also used other tests that tap more into the Cattell-Horn-Caroll theory of intelligence in relation to gender. For example, a 2008 study by researcher Timothy Z. Keith on 25 subtests of Woodcock-Johnson Tests of Cognitive abilities, along with a sample of 6,818 adults and children from 6 to 59 found females scoring higher on the latent processing speed (Gs)factor, a small male advantage on the latent comprehension–knowledge (Gc) factor, higher male score on the latent visual–spatial reasoning (Gv)and higher male latent quantitative reasoning (RQ) factor. The study found no difference in latent long-term retrieval (Glr,short-term memory (Gsm), auditory processing (Ga) and fluid intelligence(Gf) factors. However the sex difference in general intelligence (g-factor) was inconsistent in children with small higher female g factor during adolescence, and consistent higher female latent g factor during adulthood. The finding of the study confirmed Lynn's theory that males develop slower, but did not replicate results that males after 16 years old should have higher g factor. Lead researcher Timothy Keith suggests past researchers like Lynn's had used emergent scores to calculate g factor which is not accurate since most intelligent theories define g factor as a latent variable and not an emergent one. Researcher Timothy Z Keith replicated the same results again in the same year when he conducted a study of 3,025 6-18 year old participants with higher female latent g factor at all ages. In 2006, researchers Stephen Camarata and Richard Woodcock also replicated the exact same results in sample of 4,253 children and adults but found no sex differences in g factor. In 2011, researcher Timothy Z.Keith also found no significant sex differences in latent g factor among participants of 5-17 year olds on a different IQ test known as the Differential Ability Scales.
In 2007, Johnson and Bouchard (2007) conducted 40-60 mental tests that were not constructed to eliminate sex differences also found no sex differences in general intelligence or g factor except in residual factors such as verbal abilities and mental rotation. Another study published in the Journal of Psychoeductional Assessment also found no sex differences in g factor in a sample size of 744 5-85 year old participants on the Wide Range Intelligence Test. A 2009 study published in the Archives of Clinical Neuropsychology also found no sex differences in fluid intelligence except female 8 point advantage on writing and male 4 point advantage in math among 22-90 year old participants in a sample of 500 participants. A 2015 study published in the journal of Psychology in Schools found no sex differences on standardized testing of achievement except a small persistent female advantage in reading and large female advantage in writing among a nationally representative sample of 1,574 6-21 year old participants.
Debate and division among researchers
The current literature on sex differences produced inconsistent results depending on the type of testing used. Among the researchers who conducted studies on intelligence, many point that there are no sex differences in g (Jensen 1998, Colom, Garcia, Juan-Esponiza & Abad 2000, Colom, Garcia, Juan-Esponiza & Abad 2002, Camarata and Woodcock 2006), some point there are small but a real difference favoring males (Lynn 1999, Lynn Irwing 2004, 2008) and a few even found a difference favoring females (Keith, Reynolds, Patel & Ridley 2006 and Reynolds, Keith, Ridley, Patel 2006). The issues remains unresolved if one uses standardized tests as Jensen (1998) and Colom, Garcia (2002) agrees that there might be a small insignificant sex difference in intelligence in general( IQ) but this may not necessarily reflect a sex difference in general intelligence (g factor). The difference between the two concepts is that IQ is a psychometric scoring system measured with standardized testing, while g factor is a latent scientific construct that correlates with all cognitive tests and achievements in life. Although most researchers distinguish between g and IQ, those that argue for greater male intelligence assert that IQ and g are synonymous (Lynn & Irwing 2004) and so the real division comes from defining IQ in relation to g factor. However in 2008 Lynn and Irwing proposed that since working memory ability correlate highest with g factor, researchers would have no choice but to accept greater male intelligence if differences on working memory tasks are found. As a result, a neuroimaging study published by Schmidt (2009) conducted an investigation into this proposal by measuring sex differences on a n-back working memory task. The results found no sex difference in working memory capacity and thus contradicting the position pushed forward by Lynn and Irwing (2008) and more in line with those arguing for no sex differences in intelligence The same results in the 2009 n-back working memory study have also been replicated in numerous other studies since.
American Psychological Association
In a 2012 review by researchers Richard E. Nisbett, Joshua Aronson, Clancy Blair, William Dickens, James Flynn, Diane F. Halpern and Claremont Eric Turkheime , discussed Arthur Jensen's 1998 studies on sex differences in intelligence in tests that were significantly g loaded but were not set-up to get rid of any sex differences(read differential item functioning). They summarized his conclusions as he quoted "No evidence was found for sex differences in the mean level of g or in the variability of g.Males, on average,excel on some factors; females on others”. Jensen’s results that no overall sex differences existed for g has been reinforced by researchers who analyzed this issue with a battery of 42 mental ability tests and found no overall sex difference.
Although most of the tests showed no difference, there were some that did. For example, they found female performed better on verbal abilities while males performed better on visuospatial abilities. For verbal fluency, females have been specifically found to perform slightly better in vocabulary and reading comprehension but significantly higher in speech production and essay writing. Males have been specifically found to perform better on spatial visualization, spatial perception, and mental rotation. Researchers had then recommended that general models such as fluid and crystallized intelligence be divided into verbal, perceptual and visuospatial domains of g, because when this model is applied then females excel at verbal and perceptual tasks while males on visuospatial tasks. Thus evening out the sex differences on IQ tests.
Some studies have identified the degree of IQ variance as a difference between males and females. Males tend to show greater variability on many traits for example having both highest and lowest scores on tests of cognitive abilities, though this may differ between countries.
The variability hypothesis still evokes controversy, but recent data and analyses may bring some closure to the debate […] Data from a number of representative mental test surveys, involving samples drawn from the national population, have become available in the past twenty years in the USA. These have finally provided consistent results. Both Feingold (1992b) and Hedges and Nowell (1995) have reported that, despite average sex differences being small and relatively stable over time, test score variances of males were generally larger than those of females. Feingold found that males were more variable than females on tests of quantitative reasoning, spatial visualisation, spelling, and general knowledge. […] Hedges and Nowell go one step further and demonstrate that, with the exception of performance on tests of reading comprehension, perceptual speed, and associative memory, more males than females were observed among high-scoring individuals.
Psychologist and psychometrician Steve Blinkhorn published a criticism in the journal Nature against Richard Lynn and Paul Irwing on their meta-analysis of sex differences, where he pointed out their flaw in excluding an intelligence study from Mexico that accounted for almost 45% of the data. He claimed that had it not been excluded, no sex differences would have been found. He highlighted the need for proper research designs instead of summing up through meta-analysis.
A 2008 study by Earl Hunt published in the journal Intelligence found that sex differences on tests can result from recruitment factors such as gender differences only representative of those that actually participate in the studies. He also contested that not only can there be individual variations that the studies consistently recruits, but that it wouldn't be representative of the general population especially if the participants only represent college students. A 2009 study by researcher Dominika Dykiert published Intelligence also found that sex differences in mean IQ scores can be partly created by male variability in cognitive abilities and sample restriction. Dykiert highlighted the need for representative samples for studying sex differences in intelligence to eliminate skewed results created by male variance and restriction of sample. Studies have also indicated that tests used to measure sex differences such as Raven's Progressive matrices is not a pure indicator of general intelligence or g factor and only shares 50% of its variance. Tests like WAIS have also been criticized as not directly measuring g factor in a 2002 study published in Intelligence. Lead researcher Roberto Colom has strongly asserted that g factor or general intelligence is the correlation among different test scores and not the summed scores on different tests, such as Raven's or WAIS. Roberto Colom has also pointed out that Raven's Progressive matrices is biased against females because of the visuospatial nature of the test which which tend to favor those with stronger visuospatial skills (i.e. males) instead of g factor. Therefore, he concluded that sex difference research should not be based on a single test but instead with multiple tests loaded with fluid intelligence.
Brain and intelligence
Differences in brain physiology between sexes do not necessarily relate to differences in intellect. Haier et al. found in a 2004 study that "Men and women apparently achieve similar IQ results with different brain regions, suggesting that there is no singular underlying neuroanatomical structure to general intelligence and that different types of brain designs may manifest equivalent intellectual performance. For men, the gray matter volume in the frontal and parietal lobes correlates with IQ; for women, the gray matter volume in the frontal lobe and Broca's area (which is used in language processing) correlates with IQ.
Although men have bigger brain size which is partly explained by their bigger bodies, women have greater cortical thickness, cortical complexity and cortical surface area (controlling for body size) which compensates for smaller brain size. Meta-analysis and studies have found that brain size only explains 6-12 % of variance among individual intelligence and cortical thickness explains 5%.
A 2012 study published in Intelligence by researchers Miguel Burgaleta and Richard Haier dispelled previous claims that bigger brain size indicates greater male g factor than females. They found greater male brain size was instead associated with greater visuospatial abilities but not with g factor or general intelligence. The study also found no sex differences in g factor among the 100 participants.
While research has shown that males and females do indeed each excel in different abilities, math and science might be an exception to this.
Large, representative studies of US students show that no sex differences in mathematics performance exist before secondary school. During and after secondary school, historic sex differences in mathematics enrollment account for nearly all of the sex differences in mathematics performance. However, a performance difference in mathematics on the SAT exists favoring males, though differences in mathematics course performance measures favor females. In 1983, Benbow concluded that the study showed a large sex difference by age 13 and that it was especially pronounced at the high end of the distribution. However, Gallagher and Kaufman criticized Benbow's and other reports finding males overrepresented in the highest percentages as not ensuring representative sampling.
In a 2008 study paid for by the National Science Foundation in the United States, researchers found that "girls perform as well as boys on standardized math tests. Although 20 years ago, high school boys performed better than girls in math, the researchers found that is no longer the case. The reason, they said, is simple: Girls used to take fewer advanced math courses than boys, but now they are taking just as many." However, the study indicated that, while on average boys and girls performed similarly, boys were overrepresented among the very best performers as well as among the very worst. A 2011 meta-analysis with 242 studies from 1990 to 2007 involving 1,286,350 people found no overall sex difference of performance in Mathematics. The meta-analysis also found that although there were no overall differences, a small sex difference that favored males in complex problem solving is still present in high school.
Kiefer and Sekaquaptewa proposed that a source of some women's underperformance and lowered perseverance in mathematical fields is these women's underlying "implicit" sex-based stereotypes regarding mathematical ability and association, as well as their identification with their gender. Some psychologists believe that many historical and current sex differences in mathematics performance may be related to boy's higher likelihood of receiving math encouragement than girls. Parents were, and sometimes still are, more likely to consider a son's mathematical achievement as being a natural skill while a daughter's mathematical achievement is more likely to be seen as something she studied hard for. This difference in attitude may contribute to girls and women being discouraged from further involvement in mathematics-related subjects and careers. Stereotype threat has been shown to affect performance and confidence in mathematics of both males and females. However, a review of stereotype threat literature found most studies couldn't be replicated or suffered methodological problems and concluded "that although stereotype threat may affect some women, the existing state of knowledge does not support the current level of enthusiasm for this as a mechanism underlying the gender gap in mathematics."
Two cross-country comparisons have found great variation in the gender differences regarding the degree of variance in mathematical ability. In most nations males have greater variance. In a few females have greater variance. Hyde and Mertz argue that boys and girls differ in the variance of their ability due to sociocultural factors.
Metastudies show a male advantage in mental rotation and assessing horizontality and verticality and a female advantage in spatial memory. A proposed hypothesis is that men and women evolved different mental abilities to adapt to their different roles in society. This explanation suggests that men may have evolved greater spatial abilities as a result of certain behaviors, such as navigating during a hunt. Similarly, this hypothesis suggests that women may have evolved to devote more mental resources to remembering locations of food sources in relation to objects and other features in order to gather food.
A number of studies have shown that women tend to rely more on visual information than men in a number of spatial tasks related to perceived orientation. However, 'visual dependence' has been found to be task specific and not a general characteristic of spatial processing that differs between the sexes. Here an alternative hypothesis suggests that heightened visual dependence in females does not generalize to all aspects of spatial processing but is probably attributable to task-specific differences in how male and females brains process multisensory spatial information.
Results from studies conducted in the physical environment are not conclusive about sex differences, with various studies on the same task showing no differences. For example, there are studies that show no difference in 'wayfinding'. One study found men more likely to report having a good sense of direction and are more confident about finding their way in a new environment, but evidence does not support men having better map reading skills. Women have been found to use landmarks more often when giving directions and when describing routes. Additionally, a study concludes that women are better at recalling where objects are located in a physical environment. Women show greater proficiency and reliance on distinctive landmarks for navigation while males rely on an overall mental map.
Performance in mental rotation and similar spatial tasks is affected by gender expectations. For example, studies show that being told before the test that men typically perform better, or that the task is linked with jobs like aviation engineering typically associated with men versus jobs like fashion design typically associated with women, will negatively affect female performance on spatial rotation and positively influence it when subjects are told the opposite. Experiences such as playing video games also increase a person's mental rotation ability. A study from the University of Toronto showed that differences in ability get reduced after playing video games requiring complex mental rotation. The experiment showed that playing such games creates larger gains in spatial cognition in females than males. However, male participants still performed superior to female participants both before and after training
The possibility of testosterone and other androgens as a cause of sex differences in psychology has been a subject of study. Adult women who were exposed to unusually high levels of androgens in the womb due to congenital adrenal hyperplasia score significantly higher on tests of spatial ability. Many studies find positive correlations between testosterone levels in healthy males and measures of spatial ability. However, the relationship is complex.
A study was done to compare the relationship between mental rotation ability and gender difference specifically with the SAT-Math. Cognitive gender differences are apparent and findings of a male advantage in certain mathematical domains have been demonstrated cross-culturally. These gender differences found are largely in geometry and word problems and tend to be in countries with the highest achieving students and with the largest gender gap in experience. Smaller differences were noted in countries with lower achieving students in mathematics which includes the United States. Moore and Smith state that within the United States, poorly educated female students outperform their male peers, but as the level of education increases, the male advantage in mathematics emerges.
Spatial ability may be responsible in part for facilitating gender differences in math aptitude. Casey et al. (1995) looked at the relationship of mental rotation ability and the SAT-M among four samples. The four samples were: (1) undergraduates at two liberal arts colleges in the Northeast that were tested on their mental rotation ability in groups of 10-20, (2) a group of mathematically talented preadolescents participating in a summer math and science training in the Midwest which included seventh to ninth graders who were either recruited from a national talent search program or statewide teacher selection program, (3) a high ability group of college bound students who were enrolled in a middle-income suburban high school in the Northeast and elected to take the SAT, and (4) a low ability group of college bound students who were enrolled in a middle-income suburban high school in the Northeast and elected to take the SAT. The data used were SAT math and verbal scores and mental rotation scores. Mental rotation was assessed using the Vandenberg Test of Mental Rotation. Students were asked to match two out of four choices to a standard figure.
The study found that that when mental rotation is used as a predictor of Math aptitude for female students, the correlations between mental rotation and SAT-Math scores ranged from 0.35 to 0.38 whereas males showed no consistent pattern. Male correlations ranged from -0.03 to 0.54. However, an interesting finding was that in the three high ability samples, there was a significant gender difference in SAT-Math scores alone. This difference favored males. In the three high ability samples, males scored higher than females in mental rotation ability. Interesting enough, for the verbal aptitude test on SAT, there was a significant difference in verbal ability for the low ability college bound sample favoring girls.
Sex differences in academics
A 2014 meta-analysis of sex differences in scholastic achievement published in the journal of Psychological Bulletin found females outperformed males in teacher-assigned school marks throughout elementary, junior/middle, high school and at both undergraduate and graduate university level. The meta-analysis done by researchers Daniel Voyer and Susan D. Voyerwas from the University of New Brunswick drew from 97 years of 502 effect sizes and 369 samples stemming from the year 1914 to 2011, and found that higher female performance was not affected by publication year and thereby contradicted recent complaints of "boy crisis" in academic achievement. Another 2015 study by researchers Gijsbert Stoet and David C. Geary in Intelligence found that girl's overall education achievement is better in 70 percent of all the 47–75 countries that participated in PISA. The study consisting of 1.5 million 15 year olds found higher overall female achievement across reading, mathematics, and science literacy and better performance across 70% of participating countries including many with negative gaps in socioeconomic and gender equality, and they fell behind in only 4% of countries. Stoet and Geary concluded that sex differences in educational achievement are not reliably linked to gender equality.
Dyslexia is a learning disability that impairs a person’s fluency or comprehension accuracy in being able to read. The cause of this disability is associated with abnormal brain anatomy and function. Gray matter deficits have been demonstrated in dyslexics using structural magnetic resonance imaging. This deficit has been found in specific regions within the left hemisphere involved in language.
There is higher prevalence of dyslexia in males than in females. However, different abnormalities are found in female brains as opposed to male brains. In a study that examined gray matter volume in dyslexic females, it was found that there was less gray matter volume in the right precuneus and paracentral lobule/medial frontal gyrus. In males, there was less gray matter volume in the left inferior parietal cortex. This study shows that dyslexia in females does not involve the left hemisphere regions involved in language as it does in males. Instead, it affects the sensory and motor cortices such as the motor and premotor cortex and primary visual cortex.
- Sex differences in humans
- Sex differences in psychology
- Sex differences in emotional intelligence
- Emotional intelligence
- van der Sluis, Sophie; Posthuma, Danielle; Dolan, Conor V.; de Geus, Eco J. C.; Colom, Roberto; Boomsma, Dorret I. (2006-05-01). "Sex differences on the Dutch WAIS-III". Intelligence 34 (3): 273–289. doi:10.1016/j.intell.2005.08.002.
- Dolan, Conor V.; Colom, Roberto; Abad, Francisco J.; Wicherts, Jelte M.; Hessen, David J.; van de Sluis, Sophie (2006-03-01). "Multi-group covariance and mean structure modeling of the relationship between the WAIS-III common factors and sex and educational attainment in Spain". Intelligence 34 (2): 193–210. doi:10.1016/j.intell.2005.09.003.
- Johnson, Wendy; Bouchard Jr., Thomas J. (2005-07-01). "The structure of human intelligence: It is verbal, perceptual, and image rotation (VPR), not fluid and crystallized". Intelligence 33 (4): 393–416. doi:10.1016/j.intell.2004.12.002.
- Nisbet, Richard E (2012). "Intelligence New Findings and Theoretical Developments" (PDF). Intelligence 67: 130–59. doi:10.1037/a0026699. PMID 22233090.
- Camarata, Stephen; Woodcock, Richard. "Sex differences in processing speed: Developmental effects in males and females". Intelligence 34 (3): 231–252. doi:10.1016/j.intell.2005.12.001.
- Colom, Roberto; Garcı́a-López, Oscar (2002-02-01). "Sex differences in fluid intelligence among high school graduates". Personality and Individual Differences 32 (3): 445–451. doi:10.1016/S0191-8869(01)00040-X.
- Lynn, Richard (1999). "Sex differences in intelligence and brain size: A developmental theory". Intelligence 27: 1–12. doi:10.1016/S0160-2896(99)00009-4.
- Irwing, Paul; Lynn, Richard (2005). "Sex differences in means and variability on the progressive matrices in university students: A meta-analysis". British Journal of Psychology 96 (4): 505–24. doi:10.1348/000712605X53542. PMID 16248939.
- Lynn, Richard (1994). "Sex differences in intelligence and brain size: A paradox resolved". Personality and Individual Differences 17 (2): 257–71. doi:10.1016/0191-8869(94)90030-2.
- Blinkhorn, Steve (2005). "Intelligence: A gender bender" (PDF). Nature 438 (7064): 31–2. Bibcode:2005Natur.438...31B. doi:10.1038/438031a. PMID 16267535.
- Irwing, Paul; Lynn, Richard (2006). "Intelligence: Is there a sex difference in IQ scores?". Nature 442 (7098): E1; discussion E1–2. Bibcode:2006Natur.442E...1I. doi:10.1038/nature04966. PMID 16823409.
- Jackson, Douglas N.; Rushton, J. Philippe (2006). "Males have greater g: Sex differences in general mental ability from 100,000 17- to 18-year-olds on the Scholastic Assessment Test". Intelligence 34 (5): 479–486. doi:10.1016/j.intell.2006.03.005.
- Nyborg, Helmuth (2005). "Sex-related differences in general intelligence g, brain size, and social status". Personality and Individual Differences 39 (3): 497–509. doi:10.1016/j.paid.2004.12.011.
- Colom, Roberto; Escorial, Sergio; Rebollo, Irene. "Sex differences on the Progressive Matrices are influenced by sex differences on spatial ability". Personality and Individual Differences 37 (6): 1289–1293. doi:10.1016/j.paid.2003.12.014.
- Keith, Timothy Z.; Reynolds, Matthew R.; Patel, Puja G.; Ridley, Kristen P. (2008). "Sex differences in latent cognitive abilities ages 6 to 59: Evidence from the Woodcock–Johnson III tests of cognitive abilities". Intelligence 36 (6): 502–25. doi:10.1016/j.intell.2007.11.001.
- Jorm, Anthony F.; Anstey, Kaarin J.; Christensen, Helen; Rodgers, Bryan (2004). "Gender differences in cognitive abilities: The mediating role of health state and health habits". Intelligence 32: 7–23. doi:10.1016/j.intell.2003.08.001.
- Deary, Ian J.; Irwing, Paul; Der, Geoff; Bates, Timothy C. (2007). "Brother–sister differences in the g factor in intelligence: Analysis of full, opposite-sex siblings from the NLSY1979". Intelligence 35 (5): 451–6. doi:10.1016/j.intell.2006.09.003.
- Wai, Jonathan; Cacchio, Megan; Putallaz, Martha; Makel, Matthew C. (2010). "Sex differences in the right tail of cognitive abilities: A 30year examination". Intelligence 38 (4): 412–423. doi:10.1016/j.intell.2010.04.006. ISSN 0160-2896.
- Spelke, E. (2005). "Sex differences in intrinsic aptitude for mathematics and science?: A critical review". American Psychologist 60: 950–958. doi:10.1037/0003-066X.60.9.950. PMID 16366817.
- Lips, Hilary M. (1997). Sex & Gender: An Introduction (3rd ed.). Mountain View, Calif.: Mayfield. p. 40. ISBN 1559346302.
- Denmark, Florence L.; Paludi, Michele A. (2008). Psychology of Women: A Handbook of Issues and Theories (2nd ed.). Westport, Conn.: Praeger. pp. 7–11. ISBN 0275991628.
- Thomas Gisborne, An enquiry into the duties of the female sex, Printed by A. Strahan for T. Cadell jun. and W. Davies, 1801[page needed]
- Judith Worell, Encyclopedia of women and gender: sex similarities and differences and the impact of society on gender, Volume 1, Elsevier, 2001, ISBN 0-12-227246-3, ISBN 978-0-12-227246-2[page needed]
- Fine, Cordelia (2010). Delusions of Gender: How Our Minds, Society, and Neurosexism Create Difference. W. W. Norton. ISBN 0-393-06838-2.[page needed]
- Margarete Grandner, Austrian women in the nineteenth and twentieth centuries: cross-disciplinary perspectives, Berghahn Books, 1996, ISBN 1-57181-045-5, ISBN 978-1-57181-045-8
- Burt, C. L.; Moore, R. C. (1912). "The mental differences between the sexes". Journal of Experimental Pedagogy 1 (273–284): 355–388.
- Terman, Lewis M. (1916). The measurement of intelligence: an explanation of and a complete guide for the use of the Stanford revision and extension of the Binet-Simon intelligence scale. Boston: Houghton Mifflin. pp. 68–72. OCLC 186102.
- Kamata, Akihito; Vaughn, Brandon K. "An Introduction to Differential Item Functioning Analysis". Learning Disabilities: A Contemporary Journal 2 (2): 49–69. ISSN 1937-6928.
- Neisser, Ulric; Boodoo, Gwyneth; Bouchard, Thomas J., Jr.; Boykin, A. Wade; Brody, Nathan; Ceci, Stephen J.; Halpern, Diane F.; Loehlin, John C.; Perloff, Robert (1996). "Intelligence: Knowns and Unknowns". American Psychologist 51 (2): 77–101. doi:10.1037/0003-066X.51.2.77.
- Rider, Elizabeth A. (2000). Our Voices: Psychology of Women. Belmont, California: Wadsworth. p. 202. ISBN 0-534-34681-2.
- Archer, John, Barbara Bloom Lloyd, Sex and Gender, Cambridge University Press, 2002, ISBN 0-521-63533-0, ISBN 978-0-521-63533-2[page needed]
- Sternberg, Robert J., Handbook of Intelligence, Cambridge University Press, 2000, ISBN 0-521-59648-3[page needed]
- Baumeister, Roy F (2001). Social psychology and human sexuality: essential readings. Psychology Press. ISBN 978-1-84169-019-3.[page needed]
- Baumeister, Roy F. (2010). Is there anything good about men?: how cuflourish by exploiting men. Oxford University Press. ISBN 978-0-19-537410-0.[page needed]
- Hedges, L.; Nowell, A (1995). "Sex differences in mental test scores, variability, and numbers of high-scoring individuals". Science 269 (5220): 41–5. Bibcode:1995Sci...269...41H. doi:10.1126/science.7604277. PMID 7604277.
- Colom, R; García, LF; Juan-Espinosa, M; Abad, FJ (2002). "Null sex differences in general intelligence: Evidence from the WAIS-III". The Spanish journal of psychology 5 (1): 29–35. doi:10.1017/s1138741600005801. PMID 12025362.
- Nyborg, Helmuth (July 2012). "A conversation with Richard Lynn". Personality and Individual Differences 53 (2): 79–84. doi:10.1016/j.paid.2011.02.033.
- Lynn, Richard; Irwing, Paul (2004). "Sex differences on the progressive matrices: A meta-analysis". Intelligence 32 (5): 481–498. doi:10.1016/j.intell.2004.06.008.
- Irwing, Paul (2012). "Sex differences in g: An analysis of the US standardization sample of the WAIS-III". Personality and Individual Differences 53 (2): 126–31. doi:10.1016/j.paid.2011.05.001.
- Bakhiet, Salaheldin Farah Attallah; Haseeb, Bint-Wahab Muhammad; Seddieg, Inas Fatehi; Cheng, Helen; Lynn, Richard (2015-05-01). "Sex differences on Raven's Standard Progressive Matrices among 6 to 18 year olds in Sudan". Intelligence 50: 10–13. doi:10.1016/j.intell.2015.01.013.
- Liu, Jianghong; Lynn, Richard (2015-03-01). "Chinese sex differences in intelligence: Some new evidence". Personality and Individual Differences 75: 90–93. doi:10.1016/j.paid.2014.11.002. PMC 4261186. PMID 25506114.
- "Negligible Sex Differences in General Intelligence". ResearchGate. doi:10.1016/S0160-2896(99)00035-5. Retrieved 2016-01-23.
- Flynn, Jim; Rossi-Casé, Lilia (2011). "Modern women match men on Raven's Progressive Matrices". Personality and Individual Differences 50 (6): 799–803. doi:10.1016/j.paid.2010.12.035.
- Savage-McGlynn, Emily (2012-07-01). "Sex differences in intelligence in younger and older participants of the Raven’s Standard Progressive Matrices Plus". Personality and Individual Differences. Evolution of race and sex differences in intelligence and personality: Tribute to Richard Lynn at eighty 53 (2): 137–141. doi:10.1016/j.paid.2011.06.013.
- Keith, Timothy Z.; Reynolds, Matthew R.; Patel, Puja G.; Ridley, Kristen P. "Sex differences in latent cognitive abilities ages 6 to 59: Evidence from the Woodcock–Johnson III tests of cognitive abilities". Intelligence 36 (6): 502–525. doi:10.1016/j.intell.2007.11.001.
- Reynolds, Matthew R.; Keith, Timothy Z.; Ridley, Kristen P.; Patel, Puja G. "Sex differences in latent general and broad cognitive abilities for children and youth: Evidence from higher-order MG-MACS and MIMIC models". Intelligence 36 (3): 236–260. doi:10.1016/j.intell.2007.06.003.
- Keith, Timothy Z.; Reynolds, Matthew R.; Roberts, Lisa G.; Winter, Amanda L.; Austin, Cynthia A. (2011-09-01). "Sex differences in latent cognitive abilities ages 5 to 17: Evidence from the Differential Ability Scales—Second Edition". Intelligence 39 (5): 389–404. doi:10.1016/j.intell.2011.06.008.
- Johnson, Wendy; Bouchard, Thomas J. "Sex differences in mental ability: A proposed means to link them to brain structure and function". Intelligence 35 (3): 197–209. doi:10.1016/j.intell.2006.07.003.
- Johnson, Wendy; Bouchard, Thomas J. "Sex differences in mental abilities: g masks the dimensions on which they lie". Intelligence 35 (1): 23–39. doi:10.1016/j.intell.2006.03.012.
- Shields, J. "Validity of the Wide Range Intelligence Test: Differential Effects across Race/Ethnicity, Gender, and Education Level". Journal of Psychoeducational Assessment 22 (4): 287–303. doi:10.1177/073428290402200401.
- Kaufman, A. S.; Kaufman, J. C.; Liu, X.; Johnson, C. K. "How do Educational Attainment and Gender Relate to Fluid Intelligence, Crystallized Intelligence, and Academic Skills at Ages 22-90 Years?". Archives of Clinical Neuropsychology 24 (2): 153–163. doi:10.1093/arclin/acp015.
- Scheiber, Caroline; Reynolds, Matthew R.; Hajovsky, Daniel B.; Kaufman, Alan S. "GENDER DIFFERENCES IN ACHIEVEMENT IN A LARGE, NATIONALLY REPRESENTATIVE SAMPLE OF CHILDREN AND ADOLESCENTS". Psychology in the Schools 52 (4): 335–348. doi:10.1002/pits.21827.
- Chamorro-Premuzic, Tomas; Stumm, Sophie von; Furnham, Adrian (2015-06-22). The Wiley-Blackwell Handbook of Individual Differences. John Wiley & Sons. ISBN 9781119050308.
- Schmidt, Heike; Jogia, Jigar; Fast, Kristina; Christodoulou, Tessa; Haldane, Morgan; Kumari, Veena; Frangou, Sophia (2009-11-01). "No gender differences in brain activation during the N-back task: an fMRI study in healthy individuals". Human Brain Mapping 30 (11): 3609–3615. doi:10.1002/hbm.20783. ISSN 1097-0193. PMID 19387979.
- J. A., Tende,; Tende; A., J. "Sex differences in the working memory of students in Ahmadu Bello University, Zaria, Nigeria using the N-b". IOSR Journal of Dental and Medical Sciences 2 (6): 8–11. doi:10.9790/0853-0260811.
- "N -back task to assess sex difference in working memory: A pilot study". ResearchGate. Retrieved 2016-02-02.
- Li, Ting; Luo, Qingming; Gong, Hui (2010-05-01). "Gender-specific hemodynamics in prefrontal cortex during a verbal working memory task by near-infrared spectroscopy". Behavioural Brain Research 209 (1): 148–153. doi:10.1016/j.bbr.2010.01.033. ISSN 1872-7549. PMID 20117145.
- Robert, Michèle; Savoie, Nada. "Are there gender differences in verbal and visuospatial working-memory resources?". European Journal of Cognitive Psychology 18 (3): 378–397. doi:10.1080/09541440500234104.
- "Sex differences in working memory". ResearchGate. doi:10.2466/PR0.103.5.214-218. Retrieved 2016-02-02.
- Goldstein, Jill M.; Jerram, Matthew; Poldrack, Russell; Anagnoson, Robert; Breiter, Hans C.; Makris, Nikos; Goodman, Julie M.; Tsuang, Ming T.; Seidman, Larry J. (2005-07-01). "Sex differences in prefrontal cortical brain activity during fMRI of auditory verbal working memory". Neuropsychology 19 (4): 509–519. doi:10.1037/0894-4184.108.40.2069. ISSN 0894-4105. PMID 16060826.
- (us), National Academy of Sciences; (us), National Academy of Engineering; Engineering, and Institute of Medicine (US) Committee on Maximizing the Potential of Women in Academic Science and (2006-01-01). "Women in Science and Mathematics".
- Lehrke, R. (1997). Sex linkage of intelligence: The X-Factor. NY: Praeger.[page needed]
- Lubinski, D.; Benbow, C. P. (2006). "Study of Mathematically Precocious Youth After 35 Years: Uncovering Antecedents for the Development of Math-Science Expertise". Perspectives on Psychological Science 1 (4): 316–45. doi:10.1111/j.1745-6916.2006.00019.x. JSTOR 40212176.
- Hyde, J. S.; Mertz, J. E. (2009). "Gender, culture, and mathematics performance". Proceedings of the National Academy of Sciences 106 (22): 8801–7. Bibcode:2009PNAS..106.8801H. doi:10.1073/pnas.0901265106. PMC 2689999. PMID 19487665.
- Hedges, Larry V.; Nowell, Amy (1995). "Sex Differences in Mental Test Scores, Variability, and Numbers of High-Scoring Individuals". Science 269 (5220): 41–5. Bibcode:1995Sci...269...41H. doi:10.1126/science.7604277. PMID 7604277.
- Ali, MS; Suliman, MI; Kareem, A; Iqbal, M (2009). "Comparison of gender performance on an intelligence test among medical students". Journal of Ayub Medical College, Abbottabad 21 (3): 163–5. PMID 20929039.
- Archer, John; Lloyd, Barbara (2002-07-11). Sex and Gender. Cambridge University Press. ISBN 9780521635332.
- Hunt, Earl; Madhyastha, Tara (2008-11-01). "Recruitment modeling: An analysis and an application to the study of male–female differences in intelligence". Intelligence 36 (6): 653–663. doi:10.1016/j.intell.2008.03.002.
- Dykiert, Dominika; Gale, Catharine R.; Deary, Ian J. (2009-01-01). "Are apparent sex differences in mean IQ scores created in part by sample restriction and increased male variance?". Intelligence 37 (1): 42–47. doi:10.1016/j.intell.2008.06.002.
- Gignac, Gilles E. (2015-09-01). "Raven's is not a pure measure of general intelligence: Implications for g factor theory and the brief measurement of g". Intelligence 52: 71–79. doi:10.1016/j.intell.2015.07.006.
- Colom, Roberto; Abad, Francisco J; Garcı́a, Luis F; Juan-Espinosa, Manuel (2002-09-01). "Education, Wechsler's Full Scale IQ, and g". Intelligence 30 (5): 449–462. doi:10.1016/S0160-2896(02)00122-8.
- "Education, Wechsler's Full Scale IQ, and g". ResearchGate. doi:10.1016/S0160-2896(02)00122-8. Retrieved 2016-01-28.
- Haier, Richard J.; Jung, Rex E.; Yeo, Ronald A.; Head, Kevin; Alkire, Michael T. (2005). "The neuroanatomy of general intelligence: Sex matters". NeuroImage 25 (1): 320–7. doi:10.1016/j.neuroimage.2004.11.019. PMID 15734366.
- Cosgrove, Kelly P.; Mazure, Carolyn M.; Staley, Julie K. (2007). "Evolving Knowledge of Sex Differences in Brain Structure, Function, and Chemistry". Biological Psychiatry 62 (8): 847–55. doi:10.1016/j.biopsych.2007.03.001. PMC 2711771. PMID 17544382.
- Sex difference in the human brain, their underpinnings and implications. Elsevier. 2010-12-03. ISBN 9780444536310.
- Pietschnig, Jakob; Penke, Lars; Wicherts, Jelte M.; Zeiler, Michael; Voracek, Martin (2015-10-01). "Meta-analysis of associations between human brain volume and intelligence differences: How strong are they and what do they mean?". Neuroscience & Biobehavioral Reviews 57: 411–432. doi:10.1016/j.neubiorev.2015.09.017.
- Ritchie, Stuart J.; Booth, Tom; Valdés Hernández, Maria del C.; Corley, Janie; Maniega, Susana Muñoz; Gow, Alan J.; Royle, Natalie A.; Pattie, Alison; Karama, Sherif (2015-01-01). "Beyond a bigger brain: Multivariable structural brain imaging and intelligence". Intelligence 51: 47–56. doi:10.1016/j.intell.2015.05.001. ISSN 0160-2896. PMC 4518535. PMID 26240470.
- Burgaleta, Miguel; Head, Kevin; Álvarez-Linera, Juan; Martínez, Kenia; Escorial, Sergio; Haier, Richard; Colom, Roberto. "Sex differences in brain volume are related to specific skills, not to general intelligence". Intelligence 40 (1): 60–68. doi:10.1016/j.intell.2011.10.006.
- Halpern, Diane F.; Benbow, Camilla P.; Geary, David C.; Gur, Ruben C.; Hyde, Janet Shibley; Gernsbacher, Morton Ann (2007). "The Science of Sex Differences in Science and Mathematics". Psychological Science in the Public Interest 8: 1–51. doi:10.1111/j.1529-1006.2007.00032.x.
- Ann M. Gallagher, James C. Kaufman, Gender differences in mathematics: an integrative psychological approach, Cambridge University Press, 2005, ISBN 0-521-82605-5, ISBN 978-0-521-82605-1[page needed]
- Benbow, C.; Stanley, J. (1983). "Sex differences in mathematical reasoning ability: More facts". Science 222 (4627): 1029–31. doi:10.1126/science.6648516. PMID 6648516.
- Lewin, Tamar (July 25, 2008)."Math Scores Show No Gap for Girls, Study Finds", The New York Times.
- Hyde, J. S.; Lindberg, S. M.; Linn, M. C.; Ellis, A. B.; Williams, C. C. (2008). "DIVERSITY: Gender Similarities Characterize Math Performance". Science 321 (5888): 494–5. doi:10.1126/science.1160364. PMID 18653867.
- Winstein, Keith J. (July 25, 2008). "Boys' Math Scores Hit Highs and Lows", The Wall Street Journal (New York).
- Benbow, C. P.; Lubinski, D.; Shea, D. L.; Eftekhari-Sanjani, H. (2000). "Sex Differences in Mathematical Reasoning Ability at Age 13: Their Status 20 Years Later". Psychological Science 11 (6): 474–80. doi:10.1111/1467-9280.00291. PMID 11202492.
- Lindberg, Sara M.; Hyde, Janet Shibley; Petersen, Jennifer L.; Linn, Marcia C. (2010-11-01). "New Trends in Gender and Mathematics Performance: A Meta-Analysis". Psychological Bulletin 136 (6): 1123–1135. doi:10.1037/a0021276. ISSN 0033-2909. PMC 3057475. PMID 21038941.
- Implicit Stereotypes and Gender Identification May Affect Female Math Performance. Science Daily (Jan 24, 2007).
- Wood, Samual; Wood, Ellen; Boyd Denise (2004). "World of Psychology, The (Fifth Edition)" , Allyn & Bacon ISBN 0-205-36137-4
- Stoet, Gijsbert; Geary, David C. (2012). "Can stereotype threat explain the gender gap in mathematics performance and achievement?". Review of General Psychology 16: 93–102. doi:10.1037/a0026617.
- Penner, Andrew M. (2008). "Gender Differences in Extreme Mathematical Achievement: An International Perspective on Biological and Social Factors". American Journal of Sociology 114: S138. doi:10.1086/589252.
- Machin, S.; Pekkarinen, T. (2008). "ASSESSMENT: Global Sex Differences in Test Score Variability". Science 322 (5906): 1331–2. doi:10.1126/science.1162573. PMID 19039123.
- Chrisler, Joan C; Donald R. McCreary. Handbook of Gender Research in Psychology. Springer, 2010. ISBN 9781441914644.[page needed]
- Halpern, Diane F., Sex differences in cognitive abilities, Psychology Press, 2000, ISBN 0-8058-2792-7, ISBN 978-0-8058-2792-7[page needed]
- Ellis, Lee, Sex differences: summarizing more than a century of scientific research, CRC Press, 2008, ISBN 0-8058-5959-4, ISBN 978-0-8058-5959-1[page needed]
- Eals, Marion, and Irwin Silverman. 1992. Sex differences in spatial abilities: evolutionary theory and data. In The Adapted Mind: Evolutionary Psychology and the Generation of Culture, edited by J. H. Barkow. New York: Oxford University Press.[page needed]
- Jones, C. M; Healy, S. D (2006). "Differences in cue use and spatial memory in men and women". Proceedings of the Royal Society B: Biological Sciences 273 (1598): 2241–2247. doi:10.1098/rspb.2006.3572.
- Geary, David C. (1998). Male, female: The evolution of human sex differences. American Psychological Association. ISBN 1-55798-527-8.[page needed]
- New, J.; Krasnow, M. M; Truxaw, D.; Gaulin, S. J.C (2007). "Spatial adaptations for plant foraging: Women excel and calories count". Proceedings of the Royal Society B: Biological Sciences 274 (1626): 2679–2684. doi:10.1098/rspb.2007.0826.
- Witkin, H. A., Lewis, H. B., Hertzman, M., Machover, K., Meissner, P. B. & Wapner, S. (1954) Personality Through Perception. An Experimental and Clinical Study. Harper, New York.
- Linn, Marcia C.; Petersen, Anne C. (1985). "Emergence and Characterization of Sex Differences in Spatial Ability: A Meta-Analysis". Child Development 56 (6): 1479–98. doi:10.2307/1130467. JSTOR 1130467. PMID 4075870.
- Barnett-Cowan, M.; Dyde, R. T.; Thompson, C.; Harris, L. R. (2010). "Multisensory determinants of orientation perception: Task-specific sex differences". European Journal of Neuroscience 31 (10): 1899–907. doi:10.1111/j.1460-9568.2010.07199.x. PMID 20584195.
- Devlin, Ann Sloan, Mind and maze: spatial cognition and environmental behavior, Praeger, 2001, ISBN 0-275-96784-0, ISBN 978-0-275-96784-0[page needed]
- Montello, Daniel R.; Lovelace, Kristin L.; Golledge, Reginald G.; Self, Carole M. (1999). "Sex-Related Differences and Similarities in Geographic and Environmental Spatial Abilities". Annals of the Association of American Geographers 89 (3): 515–534. doi:10.1111/0004-5608.00160.
- Miller, Leon K.; Santoni, Viana (1986). "Sex differences in spatial abilities: Strategic and experiential correlates". Acta Psychologica 62 (3): 225–35. doi:10.1016/0001-6918(86)90089-2. PMID 3766198.
- Kimura, Doreen (May 13, 2002). "Sex Differences in the Brain: Men and women display patterns of behavioral and cognitive differences that reflect varying hormonal influences on brain development", Scientific American.
- National Geographic - My Brilliant Brain "Make Me a Genius" http://video.google.com/videoplay?docid=-6378985927858479238#
- Paula J. Caplan, Gender differences in human cognition, Oxford University Press US, 1997, ISBN 0-19-511291-1, ISBN 978-0-19-511291-7[page needed]
- Newcombe, N. S. (2007). Taking Science Seriously: Straight thinking about spatial sex differences. In S. Ceci & W. Williams (eds.), Why aren't more women in science? Top researchers debate the evidence (pp. 69-77). Washington, DC: American Psychological Association.
- "SPATIAL COGNITION AND GENDER Instructional and Stimulus Influences on Mental Image Rotation Performance". Psychology of Women Quarterly 18: 413–425. doi:10.1111/j.1471-6402.1994.tb00464.x.
- McGlone, Matthew S.; Aronson, Joshua (2006). "Stereotype threat, identity salience, and spatial reasoning". Journal of Applied Developmental Psychology 27 (5): 486–493. doi:10.1016/j.appdev.2006.06.003.
- Hausmann, Markus; Schoofs, Daniela; Rosenthal, Harriet E.S.; Jordan, Kirsten (2009). "Interactive effects of sex hormones and gender stereotypes on cognitive sex differences—A psychobiosocial approach". Psychoneuroendocrinology 34 (3): 389–401. doi:10.1016/j.psyneuen.2008.09.019. PMID 18992993.
- Cherney, Isabelle D. (2008). "Mom, Let Me Play More Computer Games: They Improve My Mental Rotation Skills". Sex Roles 59 (11–12): 776–86. doi:10.1007/s11199-008-9498-z.
- Feng, J.; Spence, I.; Pratt, J. (2007). "Playing an Action Video Game Reduces Gender Differences in Spatial Cognition". Psychological Science 18 (10): 850–5. doi:10.1111/j.1467-9280.2007.01990.x. PMID 17894600.
- Resnick, Susan M.; Berenbaum, Sheri A.; Gottesman, Irving I.; Bouchard, Thomas J. (1986). "Early hormonal influences on cognitive functioning in congenital adrenal hyperplasia". Developmental Psychology 22 (2): 191–198. doi:10.1037/0012-16220.127.116.11.
- Janowsky, Jeri S.; Oviatt, Shelia K.; Orwoll, Eric S. (1994). "Testosterone influences spatial cognition in older men". Behavioral Neuroscience 108 (2): 325–32. doi:10.1037/0735-7044.108.2.325. PMID 8037876.
- Gouchie, C; Kimura, D (1991). "The relationship between testosterone levels and cognitive ability patterns". Psychoneuroendocrinology 16 (4): 323–34. doi:10.1016/0306-4530(91)90018-O. PMID 1745699.
- Nyborg, H. (1984). "Sex Differences in the Brain - the Relation Between Structure and Function". Progress in brain research. Progress in Brain Research 61: 491–508. doi:10.1016/S0079-6123(08)64456-8. ISBN 978-0-444-80532-4. PMID 6396713.
- Casey, M. Beth; Nuttall, Ronald; Pezaris, Elizabeth; Benbow, Camilla Persson (1995). "The influence of spatial ability on gender differences in mathematics college entrance test scores across diverse samples". Developmental Psychology 31 (4): 697–705. doi:10.1037/0012-1618.104.22.1687.
- Voyeur, Daniel (2014). "Gender Differences in Scholastic Achievement: A Meta-Analysis" (PDF). Psychological Bulletin 140: 1174–1204. doi:10.1037/a0036620.
- Stoet, Gijsbert; Geary, David C. (2015-01-01). "Sex differences in academic achievement are not related to political, economic, or social equality". Intelligence 48: 137–151. doi:10.1016/j.intell.2014.11.006.
- "Dyslexia Information Page".
- Sun, Ying-Fang; Lee, Jeun-Shenn; Kirby, Ralph (2010). "Brain Imaging Findings in Dyslexia". Pediatrics & Neonatology 51 (2): 89–96. doi:10.1016/S1875-9572(10)60017-4.
- Evans, Tanya M.; Flowers, D. Lynn; Napoliello, Eileen M.; Eden, Guinevere F. (2013). "Sex-specific gray matter volume differences in females with developmental dyslexia". Brain Structure and Function 219: 1041–1054. doi:10.1007/s00429-013-0552-4.