Intelligence Flashcards
The importance of implicit theories
1) Important to everyday life
2) Can give rise to formal theories of intelligence
3) Can help to question formal theories
What are implicit theories?
- Individuals develop theories, beliefs and deeply held schema about human attributes
- As an attribute, intelligence is subject to this
Explicit vs implicit theories of intelligence
- Explicit: these are conscious ideas about intelligence
- Implicit: these are unconscious ideas about intelligence. It links to unconscious bias
Costa and Faria (2018): impact of implicit theories on education
- Meta analysis of studies looking at the role of personal implicit theories of intelligence on academic performance
- Looked at 46 studies, all of which measured participants’ implicit theories of intelligence using self-report scales. These theories ranged from entity theory (intelligence cannot be changed) to incremental theory (intelligence can be developed through effort and learning)
- Academic performance was then measured to see if it correlated with how the individual viewed intelligence
- There was a low but significant correlation between implicit theories and academic performance
- Those who viewed intelligence as malleable were more likely to have better grades overall
Heslin et al (2005): impact of implicit theories on work
- They considered the role of implicit theories managers hold around personality, ability and intelligence influences their recognition in employee behaviours
- Across 4 studies they looked at:
1) Recognition of improved performance after poor performance: those with a malleable view were more likely to recognise improved performance compared to those with a fixed view
2) Recognition of declining performance after good performance: those with malleable view were more likely to recognise declining performance
3) Effect of irrelevant poor performance information on performance ratings: the irrelevant poor performance was more likely to impact the performance rating of those with a fixed view
4) If holding a manger to hold a different implicit belief would impact their appraisal ratings: exposing those with a fixed view to malleable beliefs could modify their view to a more malleable one, and those that adopt this view were more open to acknowledging changes in employee performance
Sternberg, Conway, Ketron and Bernstein (1981): layperson theories of intelligence
- Explored how laypeople conceptualise intelligence
- Participants:
61 people studying in college library
63 people entering a supermarket
62 people waiting at a train station - They were all asked to list behaviours they were believed were characteristics of: intelligence, academic intelligence, everyday intelligence, unintelligence
- Then a different group of participants were presented with the behaviours listed by the first groups of participants and were asked to rate how well the behaviours reflected aspects of intelligence
- From this, Sternberg et al identified 3 primary dimensions of intelligence:
1) Practical problem-solving ability
2) Verbal ability
3) Social competence
What contributes to layperson theories of intelligence?
- Educational background
- Cultural background
- Age
- Individual experience
Cultural differences in layperson theories
- Cultural differences usually rooted in which aspects of intelligence are most valued within a culture
- Often a result of deeply rooted philosophies
- What is considered intelligence in one environment may not be considered or easily translatable to another
- It is important to note that there are still individual differences and sub-cultural differences
Western philosophical influence on theories of intelligence: Plato and Aristotle
- Plato emphasised the role of reason and intellect in understanding the world, linking intelligence to the immortal soul and it’s capacity to access eternal truths
- Aristotle built upon Plato’s ideas but categorised intelligence and soul into distinct functions. He associated these functions with different aspects of the natural world:
1) Vegetative soul: - Found in plants
- Responsible for basic life functions such as growth and reproduction
2) Sensitive soul: - Found in animals capable of movement
- Associated with sensory perception, memory, and imagination, but not reasoning
3) Intellectual soul: - Unique to humans
- Responsible for reason, abstract thinking, and intellectual pursuits
Reason = intelligence
Discursive reason vs intuitive reason
- Discursive reason: slow, deductive
- Interface reason: fast, not deductive
Western implicit theories summary
- Speed/depth of mental processing
- Verbal abilities
- Emphasis on learning
- Good memory
- Good cognitive skills
Eastern philosophical influence on intelligence theories: Confucius and Taoist
- Confucius: love each other, honour parents, do the right thing and not what is advantageous, intelligence through benevolence
- Taoist: humility, freedom from conventional judgements, ability to perceive and respond to changes, show full awareness of oneself and the world around us
5 Eastern aspects of intelligence
1) General cognitive factor intelligence (problem solving)
2) Interpersonal intelligence (relating to others harmoniously)
3) Intrapersonal intelligence (ability to assess the self objectively)
4) Intellectual self-assertion (confidence, awareness of intelligence)
5) Intellectual self-effacement (modesty)
Eastern implicit theories summary
- Similar ideas to western cultures
- But they apply not just to the individual
- They extend to social, historical and spiritual aspects of everyday life
Individualism vs collectivism
- Individualism is usually associated with western culture. The focus is on the primary of the individual
- Collectivist is usually associated with eastern culture. The focus is on collective nature of social obligation
Similarities and differences implicit theories of intelligence
- The differences mainly revolve around a focus on the individual in western culture and then in eastern cultures, there seems to be an additional focus on connections with others and the world around them
- These differences reflect the emphasis of a culture
A reduction in cross-cultural differences
- Lim, Plucker and Inn (2002): suggest that the use of western intelligence test may be changing views on intelligence within Korea. With increasing internationalisation, are layperson theories of intelligence converging across cultures
Formalised theories and tests: Galton
- He was the forefather of intelligence testing
- He was the first to suggest human-beings differ in intelligence
- He viewed intelligence as measurable and based on biological factors
- Intelligence is the ability to reason and respond to a large range of experiences through the senses
Eugenics
- A reproductive selection process within humans that aims to create children with desirable traits
- Positive eugenics: encouraging reproduction in those who have superior traits
- Negative eugenics: discouraging or eliminating reproduction in those perceived to have poor hereditary traits
Formalised theories and tests: Binet
- Father of IQ testing
- Developed a scale that was specially aimed to be an educational tool to support school children
- Developed the concept of mental age and create age norms to compare to
- Viewed intelligence as malleable
- He developed with Binet-Simon scale of intelligence
- He stood by 3 cardinal principles:
1) Test scores are for practical purposes and do not define anything innate or permanent
2) The scale is rough and cannot be used for ranking all children
3) Low scores are an indication that support is needed, not that the child is innately incapable
Formalised theories and tests: Goddard and Terman
- Terman revise Binet’s scale by adding new items and establishing new age norms, creating the Stanford-Binet scale
- Popularised the term IQ (intelligence quotient)
- First to recognise the need for representative samples to create norms
- However, they ignored Binet’s cardinal principles, and instead used the scale as something that captured a single, innate entity which they saw as intelligence
Formalised theories and test: Yerkes
- Adapted the Stanford-Binet scale to support the WW1, and help on army recruitment and assignments
Implicit vs formalised theories
- Implicit: unspoken beliefs about intelligence
- Formalised: established frameworks and models
Theories of intelligence: spearman’s ‘g’
- Spearman proposed that intelligence is a set of cognitive resources, explaining the positive correlation among test scores
- Two-factor model:
1) Specific abilities: vocabulary, mathematics, spatial
2) General intelligence (g): underlying performance on all specific abilities - This idea influenced an interest in developing a good measure of g
Modern intelligence tests: David Wechsler
- He worked with the APA initiative to develop an intelligence test for the army
- His first tests were based on Spearman’s work
Structure of WAIS: - This was made up of different components or sub-tests, some examples are:
- Vocabulary
- Similarities
- Matric reasoning
- Digit span
- Symbol search
- These sub-tests would relate to a given form of intelligence e.g working memory
IQ = actual test score / expected test score for age x 100 - To help standardise scores, Wechsler used the normal distribution curve or ‘bell curve’
Raven’s progressive matrices: John Raven (1938)
- This work deviated from the Wechsler test but was also based on the work of Spearman
- It focused on the idea that ‘g’ was an abstract ability
- He believed that the best way to test this was to design a test free from cultural influences, particularly language
- The test featured 60 non-verbal, multiple-choice questions, increasing in difficulty. It designed to measure reasoning ability
Uses of intelligence tests
- Education: special education needs
- Research: examine differences between groups and associations between intelligence and other factors
- Clinal setting: when working with brain injuries
The big 3 IQ tests
1) Lewis Terman:
- Stanford-Binet intelligence scale
- Intelligence quotient (IQ): mental age / chronological age x 100
2) David Wechsler:
- Wechsler adult intelligence scale (WAIS)
- Developed verbal and performance IQ scores and a normal distribution
3) John Raven:
- Raven progressive matrices
- Popular as it is non-verbal so enables intercultural comparison
A different view of ‘g’: L.L Thurston
- He also explored the relationship between different intelligence-based abilities
- Agreed with Spearman’s hypothesis of ‘g’
- He argued that Spearman hadn’t shown that ‘g’ was influencing the different tests, only that they correlated
- He believed that ‘g’ results from 7 primary mental abilities rather than lies behind them:
1) Associative ability
2) Number
3) Perceptual speed
4) Reasoning
5) Space
6) Verbal comprehension
7) Word fluency - This was the first real multi factor approach to intelligence
Fluid vs crystallised intelligence (Raymond Cattell)
- Fluid intelligence (Gf): the ability to solve abstract relational problems that have not been explicitly taught and are free from cultural influences
- Crystallised intelligence (Gc): the ability to solve problems that depend on knowledge acquired in school or through other experiences
Structure of intellect theory: J. P. Guildford
- Disagreed with Spearman and did not acknowledge the presence of ‘g’
- Suggested that intelligence was the result of 150 IVs
- These abilities could be combined into 3 groups:
1) Operations: mental processing
2) Content: mental material we possess that operations are performed on
3) Products: how information is stored, processed and used to make connections
Vernon’s hierarchal theory: Philip Vernon (1950, 1956)
- Argued that intelligence is made up of various groups of abilities that can be described at various levels (from specific to general)
- This theory elaborated on Spearman’s showing group factors found in between his 2-factor model of general and specific intelligence
- It proposed that intelligence can be grouped into levels: specific abilities > group factors > general intelligence
Three-striatum model of human cognitive abilities: Carroll (1993)
- Another hierarchical theory
- Similar structure to Vernon’s but integrated the vast amount of research conducted since this was proposed
- Brings together the theories we have considered
Cattle-Horn-Carroll theory: McGrew (1997)
- Another hierarchal theory
- Brings together Carroll’s and Cattell’s work
- Idea that there are 9 broad ‘g’ abilities beyond fluid and crystallised
- One of the most comprehensive and empirically supported psychometric theory
Howard Gardner’s multiple intelligence: Gardner, 1993
- This theory stems from more practical uses of intelligence e.g within education
- It disputes that intelligence is a sensory system. It is instead the sum of the processing system that can take place irrespective of sensory input
- It disagrees that intelligence is the same as a learning process. It is more like a computer that works more or less well
- It has 4 main characteristics:
1) Logical-mathematical: driven by logic and reasoning
2) Linguistic: naturally good with writing or speaking and memorisation
3) Musical: musically gifted and have a good ear for rhythm
4) Spatial: good at remembering images and are aware of surroundings
5) Bodily-kinaesthetic: love movement, have good motor skills and are aware of their own bodies
6) Interpersonal: good with people. They thrive at and enjoy social interactions
7) Naturalistic: a sensitivity to and appreciation for nature
8) Existentialism: ability to understand one’s surroundings and place within it - Proposes that each one resides in separate sections of the brain
- Each one is independent and without control from other intelligences of central functioning, however they do interact
A test for musical ability: Law and Zenter (2012)
- They developed a profile of musical perception skills (PROMS)
- This is an objective performance test
- It tries to overcome reliance on group comparisons between musicians and non-musicians
- It is multidimensional and is across 9 capacities e.g rhythm, melody etc
Sternberg’s Triarchic theory (considering context): Sternberg
- Intelligence is the ability to achieve success within a socio-cultural context
1) Componential sub-theory: the mental mechanisms that underlie successful intelligence (analytical)
2) Contextual sub-theory: the way in which people use these mechanisms to demonstrate intelligent behaviour (practical)
3) Experiential sub-theory: the role of experience in mobilising cognitive mechanisms to meet environmental demands
Changes in intelligence: the Flynn effect
- He questioned if IQ increases across generations
- He therefore suggested the need for IQ tests to be renormalised periodically in order to hold the average score at 100
What contributed to the Flynn effect?
- After genes, there is still about 20-40% of IQ variance to account for
- This means there is a large potential for environmental influences:
1) Nutrition
2) Education level
3) Different child-rearing practices
4) Technology advanced, allowing for greater access to information
The effect of environment: Batterjee et al (2013)
- Measured intelligence in 1977 and 2010 in Saudi Arabia using the Raven’s matrices
- They found there was a steady increase over time. This is likely due to the fact that Saudi Arabia was an economically developing country during this period
Factorial invariance study: Wicherts et al (2004)
- Investigated the concept of factorial invariance across different cohorts to understand the validity and consistency of IQ tests over time
- Factorial variances: this refers to whether the relationship between latent constructs (e.g verbal comprehension) and their observed measures (e.g vocabulary) remains stable across different groups or time periods. If a factor is invariant, it implies that the test scores reflect the same underlying abilities regardless of cohort
- They analysed data from 5 different studies involving cohorts spanning up to 30 years apart, using 3 different IQ tests
- They found some measures to not be factorially invariant. This indicates the relationship between subtest scores and the constructs they are supposed to measure may change across generations
- This suggests that the increase in IQ scores may be partly due to changes in the test themselves rather than an actual rise in intelligence
Duckworth and Seligman (2005): self-discipline vs IQ
- Aimed to explore the impact of self-discipline compared to IQ on academic outcomes
- They found that self-discipline accounted for twice as much variance in final grades as IQ
- Students with better self-discipline consistently outperformed peers with similar IQ levels but lower discipline
First vs second vs third degree relative
- First-degree relative: share ~50% of genes e.g parents and siblings
- Second-degree relative: share ~24% of genes e.g grandparents, aunts and uncles
- Third-degree relative: share ~12.5% of genes e.g great-grandparents, first cousins
Genotype vs phenotype
- Genotype: the genetic makeup of an individual
- Phenotype: an individual’s observable traits e.g height
Coining the idea of nature/nurture: Francis Galton
- First introduced the idea of nature vs nurture
- First to consider heritability generally in relation to Darwin’s work, particularly interested in intelligence
- Started looking familial relations and it’s connection to ‘eminence’
- Eminence: a level of achievement or skill that is more advanced than the elite or expert stage
- He then moved on to consider the role of environment
- First to consider these ideas at all, and suggested read each ideas were identical and non-identical twins, compared along with adoption studies
Genetic heritability
- This refers to the variability between parents and child- the proportion of shared variance
- If the parent and child are quite different, the proportion of shared variance is low and variability is high
- If the parent and child are very similar, the proportion of shared variance is high and low variability
- Some phenotypes, particularly psychical characteristics are entirely genetic e.g having a nose
- However, for some (e.g intelligence) it’s thought that the environment plays role
Measuring heritability in intelligence techniques (2)
- Behavioural approaches
- DNA/physiological approaches
Behavioural genetics
- Interested in estimating genetic heritability across populations
- Expressing that in terms of shared variance
- The average estimate of the proportion of variance for intelligence thought to be accounted for by genetic factors across a population
Types of studies used to assess genetic heritability
1) Family studies: parent-children share ~50% of genes. Can consider the associations here, but similarities may be due to shared environment
2) Twin studies: identical (MZ) share 100% of the same genes. Non-identical twins (DZ) share 50% of the same genes. Can compare (with non-twins) the influence of genetics
3) Adoption studies: consider the role of genes and environment. Parent/adopted or twins or sibling raised apart
What are heritability estimates of intelligence?
- This refers to the proportion of variance in intelligence within a population that can be attributed to genetic factors
- Research from studies suggests that the estimated heritability of intelligence is quite high
Genome-wide associations study
- This considers the entire set of DNA of a large group of people- searching for small variations
- The small variations that are being searched for are called SNPs (Single Nucleotide Polymorphism)
- Scientists can look for certain SNPs that potentially occur more frequently in people with a certain disease or trait
Deary et al (2012): heritability estimates of intelligence
- Investigated the genetic contribution to the stability of intelligence over the life span
- Participants at age 11 were measured in intelligence, then re-assessed at ages 65, 70 or 79. A genetic analysis was conducted simultaneously to compare genetic similarities among unrelated participants to estimate heritability
- The genetic contribution to the stability of intelligence across a lifespan was estimated at 38%. This suggests that while genetics plays a role, environmental factors also influence intelligence ability over time
- He also completed a meta analysis and found that heritability tend to increase with age, as environmental influence diminish and genetic effects manifest more fully
- Cross-cultural differences indicate the environmental contexts significantly interact with genetic factors
Using DNA to directly explore intelligence: Davies et al (2011)
- Directly considered the heritability of intelligence using:
1) Genome-wide data looking for SNPs
2) Phenotype data (measures of cognitive traits associated with intelligence) - Found that 40-50% of the variation in human intelligence is associated with SNPs
Considerations for genetic heritability
1) Conceptions of heritability and the environment
2) Different types of genetic variance
3) Assortative mating
4) The representativeness of twin and adoption studies
Concepts of genetic heritability and environment
- Abstract concepts: estimates do not tell us about specific genes or environmental variables
- Population concepts: estimates refer to a group of people. It cannot tell us about an individual
Different types of genetic variance
- Additive: genes + environment = phenotype
- Dominant: process of which genes are expressed (dominant) and not expressed (recessive)
- Epistatic: process of how genes interact. How genes will interact with others, determining whether they are expressed or suppressed
Environmental influences on intelligence
1) Biological (e.g nutrition, prenatal factor)
2) Family environment (e.g birth order, family size)
3) School and education
4) Culture
Admixture hypothesis: Rogers (2001)
- The admixture hypothesis suggests that birth order effects of intelligence and other traits are influenced by familial factors such as parental education
Resource dilution model: Galton (1874)
- This model proposes that as family size increases, parental resources are diluted, negatively impacting younger siblings’ development, including intelligence
Confluence model: Galton (1874)
- This model suggests that the intellectual environment of a family is dynamic and changes with each additional child. Birth order effects on intelligence arise from changes in this intellectual environment over time
Increases complexity of the environment impacting intelligence
1) Biological:
- Nutrition
- Lead
- Prenatal factors
2) Family environment:
- Shared and non-shared environments
- Within-family factors
- Outside family factors
- SES
- Birth order, family size
3) School and education:
- Education <-> intelligence
- IQ can predict educational outcomes
- But time in education can contribute to intelligence
4) Culture:
- Decontextualisation: this refers to the process of removing phenomena or data from their social, cultural or environmental context to focus solely on isolated attributes
- Quantification: involves expressing complex phenomena, such as intelligence, in numerical terms to facilitate measurement, comparison and analysis
- Biologisation: this is the tendency to attribute human traits, behaviours or social phenomena exclusively to biological or genetic factors
The dark side of heritability
- The concept of heritability have been linked to eugenics and discriminatory policies
- Examples include sterilisation laws, segregated education and restrictive immigration policies
The bell curve (1994)
- This was built on 6 assumptions:
1) There is such thing as a general factor of intelligence upon which humans differ
2) IQ tests are designed to measure ‘g’ and are mostly accurate
3) IQ scores match general ideas of what intelligence is (implicit theories)
4) IQ scores are stable, although not perfectly so
5) Properly administered IQ tests are not demonstrably biased against social, ethnic, economic or racial groups
6) Cognitive ability is sustainably heritable, apparently no less that 40-80%
The bell curve: propose four ideas
1) Cognitive elite: suggest there is an emergence of a CE within American based on the separation of society through college admission and the workplace
2) Socioeconomic variables and IQ: suggest that an individual’s intelligence is more important than SES for predicting economic and social welfare
3) The relationship between race and intelligence: describe evidence for the higher IQ of Asian-Americans and lower IQ of African-American in comparison to white Americans
4) The implication of social policy
The bell curve: implication for social policy
- The population of those with lower IQ is increasing as women with lower IQ tend to have more child
- They also argue that immigrants contribute towards this
- This will increase the societal problems that are associated with low IQ (e.g crime)
- Herrnstein and Murray argue the best way to tackle these problems:
1) Not to use affirmative action, as measures such as these have lead to a decrease in intelligence within education and the workplace
2) They also argue that resources should be shifted from supporting underprivileged populations to supporting the ‘cognitive elite’
The bell curve: issues with the 6 assumptions
1) ‘g’ exists and differs: research to support this back then was not so abundant. No expert consensus on this yet
2) IQ tests measure ‘g’ accurately: can be some debate over this, given the context around the origins of ‘g’
3) IQ scores match implicit theories: maybe western ideas, but there are differences in cultures and sub-cultures. There are even differences within cultures
4) IQ scores are stable: not perfectly. Intelligence may be viewed as malleable or fixed
5) IQ tests are not bias: the tests themselves may not be bias, but the theories behind them may be
6) Cognitive ability is substantially heritable: genetics only make up part of cognitive ability (environmental factors )
The bell curve: issues with stats and evidence
1) Correlation not causation: correlation between SES intelligence. There may be multiple confounding variables at play
2) Measure validity: studies using self-report measures for SES with children and no additional checks
3) Problematic research studies: over-reliance of certain academics who omit findings showing high IQ for black participants, terming this ‘inconsistent’
Sex differences in measures of intelligence
- Interest in sex differences in abilities and behaviours begun in the 1880s
- Scientists believed men were superior in mental abilities because women’s brains were smaller…
- However, research across 20th century suggests no differences
Narrative analysis
- Weighs up findings across studies by analysing whether each studies findings support or don’t support a hypothesis
Meta-analysis
- Pools together results from a number of carefully selected studies. Additional analysis is run on this pooled data
Effect size (Cohen’s d)
- Tells us how important a difference is
- Cohen’s d is a standardised measure of the magnitude of differences:
d =0.2: small effect
d =0.5: medium effect
d =0.8: large effect
Lynn and Irwing: gender differences in intelligence
- Aimed to examine potential gender differences in intelligence across different age groups using a large dataset
- Participants were pooled from 87 studies
- Findings:
1) Children (<15 years): no significant difference in intelligence between males and females - Effect size: 0.02
2) Adolescents (15-19 years): males scored 2 points higher on intelligence tests - Effect size: 0.16
3) Undergraduate students: males scored 3-5 points higher on intelligence tests - Effect size: 0.22-0.33
4) Adults: men scored 5 points higher on intelligence tests - Effect size: 0.3
Comparing specific intelligences: Maccoby and Jacklin (1974)
- Intelligences of interest were spatial ability and verbal ability
- On average: men performed better on tests of spatial ability. Women performed better on tests of verbal ability
Benbow and Stanley (1983): support from the world of gifted children (about sex differences)
- They noticed sex differences among 12-14 year olds who took the SATs early
- There was no differences between boys and girls in this group on the verbal section of this test
- But there were differences in the math section, with boys tending to do better
- Twice as many boys than girls with maths scores above 500 (out of 800), four times as many boys with score above 600, and thirteen times as many boys with score above 700
Sex differences in intelligence summary
- Small effect sizes in favour of men in general IQ (but mixed findings)
- Medium effect sizes in favour of men in spatial intelligence
- Small effect sizes in favour of men in maths ability
- No real evidence favouring women in verbal intelligence
Why might sex differences exist: biological explanations
1) Brain size/structure
2) Brain function
3) Hormones
4) Evolution
Biological explanations for sex differences in intelligence: brain size
- On average, men’s brains are on average 10% larger than women’s
- This difference is only seen from adolescence onwards due to different rates of maturity
- Link is small and has been overused as an explanation
Biological explanations for sex differences in intelligence: brain structure
- Tasks are solved more efficiently when carried out by one side of the brain
- Allen et al (1991): found females have a bigger splenium
- Steinmetz (1995): found females tend to have larger corpus callosums
- A bigger splenium/corpus callosum may mean tasks are more evenly distributed between the hemispheres
- This supports the idea that female brains are more bilaterally organised in their representation of cognitive function
Biological explanations for sex differences in intelligence: brain functioning (Haier et al, 2005)
- Gray matter: processes information in the brain (the structures within the gray matter e.g dendrites, process information from the sensory organs
- White matter: transports the information
- Haier et al (2005): used MRI to find areas of the brain relating to intelligence. He found that IQ among females were related to more white matter areas and fewer gray matter areas than males
- This suggests that males and females can achieve the same IQ scores with different parts of the brain
- Intelligence in males may be more related to information processing (e.g spatial ability)
Biological explanations for sex differences in intelligence: hormones
- Testosterone: male sex hormone responsible for growth and development of male genitalia in womb and during adolescence
- Oestrogen: produced mostly by ovaries, responsible for female secondary sex characteristics
- Testosterone has been found to be related to higher performance in spatial ability tasks
Biological explanations for sex differences in intelligence: hormones (Choi and Silverman, 1996)
- Looked at how males and females provide directions
- They found that females gave relative directions and landmarks, whilst males have distance and cardinal directions
- Among males, testosterone was positively related to using distance and cardinal directions
- This suggests that testosterone has an effect on organisation of spatial tasks
Biological explanations for sex differences in intelligence: hormones (Barry et al, 2013)
- Females with polycystic ovary syndrome have elevated levels of testosterone
- They completed a 3D mental rotation task with shapes
- They found that the PCOS participants scored significantly higher than controls on this task
- This further supports the idea that testosterone plays a role in spatial memory
Biological explanations for sex differences in intelligence: evolutionary
- Males needed spatial ability when: hunting over large areas, engaging in warfare with others, maximising reproductive success
- Women did not need spatial abilities as much because: they gathered crops over small areas and were spatially restricted due to pregnancy and childcare
- Jones et al (2003): males with greater spatial ability were more likely to win wars, more able to supply food and maintain more relationships, more attractive to females, creating more offspring with ‘spatial ability genes’
Hoffman et al (2012): controlling for nature/biology in spatial ability
- Aimed to investigate the influence of environmental factors on spatial ability by comparing two tribes that are genetically related but differ in cultural and societal structures
- This study assumed that if biology alone explained spatial ability, no difference would be observed
- Women’s societal roles differed significantly between the two tribes, providing an opportunity to examine the impact of environmental factors
- They found that spatial abilities varied between the tribes, despite their shared genetic background:
1) In the tribe where the women were more involved in activities requiring spatial navigation (e.g gathering), their spatial abilities were advanced
2) vice versa
Environmental explanations for sex differences in intelligence
- Stereotypes:
1) General
2) Preferences
3) Toys
4) Culture
5) Education
6) Threat
7) Global inequality
Environmental explanations for sex differences in intelligence: stereotypes (general)
- Stereotypes can be a central influence
- Stereotypes about how we should behave and about how others should behave
- For example, boys tend to play with toys that encourage development of spatial awareness
- Campbell et al (2000): toy preference reflects gender stereotypes in children as young as 9 months old
Feng et al (2007): Environmental explanations for sex differences in intelligence: stereotypes
- Looked at spatial attention and mental rotation among gamers/non-gamers and males/females
- Experiment 1:
> Gamers performed better than non-gamers
> No sex differences in gamers group
> Among non-gamers, males performed better than females - Experiment 2:
> Experimental group: 10-hour action video game training
> Control group: 10-group non-action game training
> All those in E group improved in ability
> Females benefitted more than males
> In E group, no sex differences after training
> In C group, males performed better both pre and post training
Environmental explanations for sex differences in intelligence: stereotypes and preferences
- Reinforcement: mothers and fathers reinforce sex appropriate behaviour and discourage sex inappropriate behaviour (Langlois and Down, 1980)
- Modelling: children observe same sex others and gain stereotypes on how they ‘should’ behave e.g what toys to play with. This forms part of their gender identity
- Socialisation of boys: boys are often given greater freedom to explore (Entwistle et al, 1944)
Environmental explanations for sex differences in intelligence: stereotypes and toys
- Seavy, Katz and Zalk (1975): participants chose toys associated with stereotypical view of gender
- Sidorowicz and Lunney (1980): aimed to examine how adults perceived and reinforce gender-specific behaviours in children through their choices of toys:
> Male and female adults were asked to select toys for children they believed were either boys or girls
1) For a child believed to be a boy: 50% of males and 80% females chose a football for the child (as boys are stereotyped to be active and physical)
2) For a child believed to be a girl: 88.8% of males and 72.7% of females chose a doll for the child (also reflecting the stereotype of girls being nurturing and domestic)
Environmental explanations for sex differences in intelligence: stereotypes across cultures
1) Characteristics associated with males:
- Active
- Ambitious
- Daring
- Dominant
- Rude
- Self-confident
- Stong
- Tough etc
2) Characteristics associated with females
- Affectionate
- Attractive
- Curious
- Dependent
- Emotional
- Shy
- Weak
Environmental explanations for sex differences in intelligence: stereotypes and education
- Hyde et al (1990): meta-analysis. He found there was overall no gender differences in mathematics performance d =-0.05
- STEM subjects: girls are less likely to choose these subjects -they are stereotyped as ‘masculine subjects’. Therefore, less likely to develop spatial ability. WISE report (2014) found that only 21% of physics A-level entrants were female
- Moss-Racusin et al (2012): applications for lab manager in STEM subjects were randomly given male or female name. They found that faculty rated male applicants as more competent and hireable than the female (even though the applications were identical)
Environmental explanations for sex differences in intelligence: stereotype threat
- Negative stereotypes about different social groups can affect ability
- Spencer et al (1999): males and females took a math test for control condition. In the experimental condition, males and females took a math test but were told that males had performed better on this test in the past. As a result of this, females scored lower than men in this condition compared to no difference in condition 1
- Inzlicht and Ben-Zeev (2000): participants took maths and verbal tests. The first condition involved female participants with two other females (same sex). The second condition involved female participants with two males (minority). They found that performance was better in the same-sex condition for both tests (more significant different in math test)
Environmental explanations for sex differences in intelligence: global inequality
- Nations with greater gender equality portray smaller gender differences in mathematical performance
Accurate vs over/underemphasised stereotypes
- Swim (1994) found that stereotypes can often reflect real differences in ability (accurate stereotypes) as well as biased differences (over or underemphasised stereotypes)
Working together explanations for sex differences in intelligence: methods of measuring intelligence
- Olsen et al (2013): Mental rotation tasks given to both females and males. These were given on a small screen (laptop) and large screen (display wall). They found that females scored faster than males in the large screen condition. This suggests that men solve mental rotation tasks using a ‘holistic’ strategy while women use a more ‘step-like’ strategy
Other potential issues with measuring intelligence gender differences
- What is intelligence anyway?
- Are we measuring it ‘correctly’
- Focusing on the binary?
- What about the other types of intelligence?
Summary of gender differences in intelligence
- Males have been found to slightly outperform females in general intelligence (although findings are mixed)
- Males often outperform in mathematical and spatial ability tasks (although gaps are closing)
- Biological explanations:
1) Brain (size, way it’s used, areas used)
2) Hormones (Testosterone related to spatial ability)
3) Evolutionary (males needed to have greater spatial ability?) - Environmental explanations:
1) Stereotypes (males better at maths, spatial ability)
2) Socialisation of children (toy preference, social activities)
3) Education (stereotypes, perceptions of STEM subjects) - Psychobiological model:
1) Stereotypes: accurate (biological)
2) Biased (environment)
3) Brain development (synapse pruning influenced by environment)
4) Hormones (affect how children are treated)
