SPID 4.4 - Sex Differences

What did research in the 20th century determine about sex differences in IQ?

• Terman found girls having slightly higher

• Spearman’s g found no difference

• Cattell found no difference in either fluid or crystallised

• Court reviewed raven’s matrices and found no difference

No difference altogether

What was the issue with 20th century sex research?

• used narrative analysis

• Weigh up evidence presented across a number of studies

• only consists of assessing whether study supports hypothesis or not

• Sample size varies and usually less than 500

What did Lynn and Irwing’s meta analysis show?

• Pooled data from 87 studies and 80k ppts

• Small effect sizes found

• Under 15 no difference Cattell

• Males score higher from 15 onwards

What effect sizes show how important differences between groups/conditions are?

0.2 = small

0.5 = medium

0.8 = large

What did other meta-analysis find?

• nyborg found small advantage

• Colom and Spinath found none

• Others say sex differences may be because of unrepresentative samples

• Hyde’s review showed males and females are more similar than different

How did Maccoby and Jacklin study sex differences between spatial and verbal ability?

Spatial = shape matching, solids in 2D/3D

Verbal = comprehension, spelling

Men better at spatial, women at verbal

What do meta-analyses of sex differences in verbal and spatial ability show?

• Very mixed findings - mostly small effects

• Spatial ability = small-large effect sizes

• Verbal = some larger in adolescence but small when combined

• Magnitude of difference is so small it basically doesnt exist esp in adulthood

What did Benbow and Stanley’s study of gifted children tell us?

• sex differences of 12-14 year olds who took SATs early

• No difference on verbal

• Boys did better in maths With 2x more getting other than 500

• 4x with 600

• 13x with 700 (13:1 ratio)

Has the gap between gifted children changed?

13:1 reduced to 3:1

Remained at 3/4:1 since 1990s

However leads to special programs and emmroting to encourage girls into STEM

Sex differences summary

• small effect sizes in favour of men in general IQ but mixed findings

• Medium effect sizes in favour of men in spatial ability and maths

• No real evidence favouring women in verbal intelligence

What are the 4 biological explanations for sex differences in intelligence?

• brain size/strucure

• Brain function

• Hormones

• Evolution

How is brain size used a biologically explanation?

• men’s brains are 10% larger than womens

• Only seen from adolescence onwards

• Link is small and has been overused

• Previous effect sizes inflated due to reporting bias

How is brain structure used a biologically explanation?

• tasks are solved more efficiently when carried out by one side of the brain

• Females have bigger selenium and corpus callosum

• May mean tasks are more evenly distributed between hemispheres

• Women are more bizarrely organised in representation of cognitive functioning

What’s the difference between grey and white matter?

• grey matter processes info in brain as structures process signals generated in sensor organs and directs sensory stimuli to nerves

• White matter transports this info as it’s encoded in action potential and propagated along neurons, affected by WM integrity

How is brain functioning used a biologically explanation according to Haier?

• MRI to find intelligence related brain areas

• IQ among females = relates to white matter more than grey

• Male and females achieve same IQ with different parts of brain

• Male intelligence may be more related to info processing eg spatial ability

How did Choi and Silverman’s direction task give evidence of hormonal differences?

• testosterone related to higher performance in spatial ability

• Looked at men and women providing directions

• Given maps and had to learn shortest routes to provide a written direction

• Saliva samples were taken to measure hormone levels

• Women = relative directions and landmarks

• Men = distance and carinal directions positively related to testosterone

How did Barry’s PCOS study give evidence of hormonal differences?

• women with PCOS have higher levels of testosterone

• Did 3D mental rotation task

• PCOS did better

How is evolution used a biologically explanation?

• males needed spatial ability when hunting over large areas, engaging in warfare and maximising reproductive success

• Women didnt need much as they gathered crop over small areas and were spatially restricted due to pregnancy and childcare

How did Jones’ use evolution as an explanation?

• males with greater spatial ability = win wars, supply food, maintain more relationships, attract more females and more offspring

What issues are there with evolutionary explanations?

• any finding can be linked to hunter-gatherers societies

• Ignore that women did engage in spatial tasks eg travelling distances to find plants that ripen in different locations/seasons

• Ignore that women playing sig role in hunting and warfare

What did Hoffman find when examining spatial ability in different environments?

• genetically related tribes but woman played a different role in society in each

• Patriarchal = men faster

• Matriarchal = no difference

• Environment plays a role

What environmental stereotypes are used as an explanation?

• general

• Preference

• Toys

• Culture

• Education

• Threat

• Global inequality

What general toy stereotypes influence behaviour?

• boys play with toys that encourage spatial awareness

• Toy preference reflects gender stereotypes as young as 9 months

How did Feng study spatial attention among gamers and sex?

• gamers and non-gamers

• Males and females

• Gamers better than non gamers with no sex difference

• Men did better than women in non-gamers group

• Exp 2 had 10h action or non-action video game training

• Action video game group improved with females benefiting more

• No sex difference after training in action

• In contorl, males did better pre and post

What research is there of reinforcement, modelling and socialisation of each sex?

reinforcement

• mothers and fathers reinforce sex appropriate and discourage sex inappropriate

Modelling

• children observe same sex others and gain stereotypes on how they should behave

Socialisation

• boys given greater freedom to explore

When able to choose toys, what do each sex chose according to seavy/lunney?

• ppt chose toys associated with stereotypical view of gender

• 50% male, 80% female = football

• 88.8% male, 73.7% female = doll

How are gender stereotypes seen across culture?

Males

• active, dominant, tough, unemotional

Female

• emotional, shy, submissive, anxious

In 25 countries

How did Hyde et al do a meta-analysis of education and sex?

• 4 mill ppts

• No diff in maths, complex problem solving and understanding of concepts

• Slight female advantage in computation

• Replicate study found hs men did better so may be differences in course taking

Why are females less likely to choose STEM subjects?

• stereotypes as masculine

• Less likely to develop spatial ability skills

• WISE report found 21% of physics A level entrants were female (2014)

• Institute of physics found 46% of schools had no girls doing a level physics

How did Moss-Racusin study STEM stereotypes?

• applications for lab manager in STEM subjects were randomly given male or female names

• Faculty rated male applicants as more competent and hireable even tho applications were identical

How did Spencer study negative stereotyping and ability?

• male and female took maths test

• Same but told males scores better in past

• Cond 1 had no difference but cond 2 had females scoring lower

How did Ben-Zeev study negative stereotyping and ability?

• ppts took maths and verbal test

• Female ppts with 2 other females

• Female with 2 males

• Not told just presence

• No diff in verbal

• Females did worse in maths when performing with males

What global inequalities exist?

• nations with greater gender quality have smaller gender differences in maths

• Eg Northern Europe

Why was the psychobiological model created?

• dont know whether biological differences influence sex differences and stereotypes or other way round

• Learning experiences have an influence as synaptic pruning occurs

• hormones determine sex/aggression/temperament

• parents encouraging certain activities based on these

• Swim = stereotypes can reflect real differences in ability as well as biased differences

How did Olsen study different strategies used by the sexes?

• mental rotation task on small screen and large screen

• Females did better on large screen

• Men solve mental rotation using holistic, women with step like strategy

How are generalisations harmful?

• female mathematicians exist

• Top scoring females on international mathematical Olympiad

• An increase in female ppts with time

Summary

• males slightly outperform females in g

• Males outperform females in maths and spatial ability but gap is closing

• Bio exp = brain, hormones and evolutionary

• Env exp = stereotypes, socialisation, education

• Physiobioloigcal = stereotypes, biased, brain development and hormones