Understanding the relationship between education and general cognitive skills

1. Understanding the relationship between education and general cognitive skills Richard Cowan

2. Overview • Explaining the association • Past views • Early educational psychology • Development and individual differences • Dynamic relationship • Other factors

3. The association • The correlation between school children’s educational achievement and general cognitive skills is typically about .5 • One of the most reliable findings in psychology • Understanding it is important for • psychological practice, e.g. assessment of learning difficulties • curriculum planning • public debate

4. Origins • Ideas about the relations between education and general cognitive skills pre-date empirical psychology • Curriculum planning in education makes implicit assumptions about how education affects the development of general cognitive skills • There are subjects and ways of teaching that we believe encourage learners to think for themselves • At the same time differences between learners acknowledged, even if the contributions of prior knowledge, personality, motivation, and general cognitive skills disputed

5. Curriculum planning emphasis Education General cognitive skills

6. Individual differences emphasis Education General cognitive skills

7. Past views • From Plato onward, many educational theorists acknowledged effects in both directions • The assumption of mass educability led to downplaying the role of differential cognitive skills

8. 19th century psychology • Faculty psychology originated in mental philosophy • Claimed mind consists of separate faculties • Number of faculties disputed • Cognitive faculties (memory, reasoning, morality, imagination) differentiated from emotions and will

9. Applied to education • Mental discipline: developing cognitive faculties so they could control the will and emotions • Subjects to develop particular faculties • History for morality • Mathematics, particularly geometry, for developing reasoning • Rote learning poetry to develop memory

10. Exercises and transfer • Physical exercises that benefit muscle groups produce gains that transfer automatically to activities that use them • The mental discipline view: activities that develop cognitive faculties would also automatically transfer

11. Herman Hesse • InThe prodigy • Criticisesconventional schooling for the neglect of personal development • And the mechanical approach of mental discipline

12. Pioneers of psychology William James Edward Thorndike

13. Early educational psychology • James questioned faculty psychology • Thorndike assessed mental discipline claims empirically • Studies of learning did not find automatic transfer • Gains on tests of thinking skills were not related to choice of secondary school subjects as predicted by leading version of mental discipline • But individual differences in thinking skills did predict differences in school grades

14. Individual differences • Thorndike found low correlations between scores on contemporary cognitive skills – academic intelligence - tests • Combined with findings of limited transfer inspired his theory of numerous specific abilities • The only general ability is the ability to form associations • Differences in this ability depend on experience and genetic influences

15. Spearman Suggested another explanation for low correlations between tests: one general ability, g, and many specific abilities Developed factor analysis to show g Identified two components of g: Eductive – matrices tests have high loadings Reproductive – vocabulary tests and factual knowledge

16. Misunderstanding g • In 1920s Spearman resisted identifying g with intelligence because of the confusions and controversies talk of intelligence involves and common misconceptions • These still exist • Belief that differences in intelligence test scores wholly due to genetic variation: refuted by behavioural genetics • Belief that intelligence is fixed: no foundation (Binet)

17. Variability in g is not all genetic • Heritability is the amount of variation between individuals that is attributable to variation in genes • It varies from 0 to 1 or from 0% to 100% • Comparisons of MZ (identical) twins and DZ twins have been used to estimate heritability • Although studies vary, in general estimated heritability of g increases with age: 20% in infancy, 40% in middle childhood, 50% in adolescence and adulthood

18. Nor are maths and reading variability • The Twins Early Development study is a longitudinal study of identical and non-identical twins in the UK • In samples of up to 5000 pairs of twins, heritability of 10-year-olds’ maths and reading is similar to that of g (36 - 48%) • That is notable but much less than 100%

19. But misunderstanding persists • ‘Parents have long battled to persuade their children to master new spellings and learn their tables, but they may be wasting their time. A new study suggests that both maths and reading ability lies largely in the genes.’

20. Absolute g is not constant • Performance on all general cognitive skills tests improves substantially with age during elementary school • This is why psychometric tests of general cognitive skills use a child’s chronological age in calculating standard score

21. Matrix reasoning (RAVEN SPM)

22. Receptive vocabulary (BPVS II)

23. And neither is relative g • Individual differences at one age are not perfectly related to differences at other ages • For example g at 7 years correlates about .4 with g at 9 and 10 • And g at 9 years correlates about .6 with g at 10

24. Dynamic relationship Education General cognitive skills

25. Assessing dynamic relationships • Requires a longitudinal design, with repeated measures of both education and general cognitive skills (g) • Influence of education on g: If education at time 1 predicts g at time 2, even when controlling for g at time 1 • Influence of g on education: If g at time 1 predicts educationat time 2, even when controlling for educationat time 1

26. English, Maths, and g • The Twins Early Development study collected data on English, Maths, and g from children at the ages of 7, 9, and 10 • Selecting one member of each twin pair who participated at all ages yielded a sample of 1074 • I ran regressions of data at 9 on performance at 7, and regressed data at 10 onto performance at 9

27. From 7 to 9: βs and overall R2

28. From 9 to 10

29. English t1 English t2 • Maths t1 Maths t2 G t1 G t2

30. So • Each measure explains variation in the other at a later point even when prior performance included • Results consistent with dynamic relation between education and general cognitive skills • But this may not be the whole story

31. Taking into account other factors Education General cognitive skills Other variables

32. Other factors • Genetic factors • Contextual factors at home and school: support, setting, and beliefs • Self-beliefs: mindsets, motivation, and self-concepts • Deliberate or incidental practice • Much to find out!

33. Thank you Institute of Education University of London 20 Bedford Way London WC1H 0AL Tel +44 (0)20 7612 6000 Fax +44 (0)20 7612 6126 Web www.ioe.ac.uk