Intelligence
Part 1
IQ is an index of an individuals intelligence score, tests of IQ can be non
verbal or verbal
Advantages of non verbal tests eliminate issues with language, verbal abilities
and cultural differences.
Key figures and the dark history of intelligence
Francis Galton : reasoned that intelligence is a product of natural selection, thus
must be genetically determined. Saw potential in theory of evolution for planned
human development (betterment).
Binet & Simon: developed 1st IQ tests to measure student abilities for education
purposes – determine which children would make the most out of education
eliminating factors such as personality differences and social class differences giving
equal. Opportunity for them to perform well and get a good education.
Lewis Terman and Maud Merrill
o Devised the Stanford-Binet scale
o Studied a sample of ‘gifted’ children throughout their lives – IQ of about 140
(longitudinal study)
o Highly intelligent individuals not weaklings and misfits but healthy and stable
Lewis Terman
o Military use (Alpha, Beta test) to assign soldiers to tasks appropriate to their
abilities during WW1
o Eugenics: promote selective breeding to cultivate desirable characteristics
(intellectually and physically)
Cyril Burt
o Advised the British government to use aptitude tests to determine which
children will go on to grammar schools (11+)
o His research on intelligence seemed to suggest that occupational levels and
social class are determined by innate and heredity levels of intelligence.
o Problems with data and analysis – fabricated?
Dark history of intelligence
Other issues
o Cultural bias in test construction and standardization procedures
o Intelligence tests favour groups from more affluent backgrounds and
discriminate against less privileged racial, ethnic or social groups.
Non-verbal IQ test e.g. Raven’s Progressive Matrices
More recent IQ tests
WISC (Wechsler Intelligence Scale for Children)
WASI (Wechsler Adult Scale for Intelligence)
Include verbal and non-verbal tests (tap into both crystalised and fluid intelligence)
, Basic concepts
Genotype = genetic makeup of an organism
Phenotype = observable physical properties of an organism; these include organisms’
appearance, development, and behaviour. Phenotype includes both genotype and
environmental influences
We can only measure phenotype. Performance depends on many factors.
Degrees of genetic relatedness = looking at people with various degrees of
relatedness can give us an understanding of the genetic basis of a concept. E.g.
identical twins share 100% of genetic makeup compared to siblings (50%) and
compare these to find out how much of the performance is genetically determined.
Atheoretical definition of intelligence = intelligence is what IQ tests measure. No
theory of intelligence that will determine what questions should be included in an IQ
test.
However: IQ tests highly correlate with each other and with other measures (e.g.
WM, Academic performance, problem solving, reasoning, career and income)
Correlation = statistical test and term that examines the relationship between 2 or
more variables.
Part 2
Is intelligence a single construct?
Generalised intelligence
o Single construct that influences all our cognitive functioning
o Demonstrated through correlations of performances on different tests
o Measures include
Stanford – Binet
Raven’s progressive matrices
Or is intelligence a multiple construct?
Composed of fluid and crystalised intelligence (Catell, 1987)
o Fluid intelligence – cog. Functioning component not influenced by the
environment, fixed throughout lifetime
o Crystalised intelligence – stored factual information, benefits from schooling
can change throughout life span
Supported by correlations between tests of FI. and CI. Respectively
Both interact in some ways
Relatively stable FI. But increasing CI. across life span
Is intelligence determined by genes or the environment?
Twin studies – valuable to examine genetic characteristics. However hard to separate
genetics and environmental factors in IQ test performance
Part 1
IQ is an index of an individuals intelligence score, tests of IQ can be non
verbal or verbal
Advantages of non verbal tests eliminate issues with language, verbal abilities
and cultural differences.
Key figures and the dark history of intelligence
Francis Galton : reasoned that intelligence is a product of natural selection, thus
must be genetically determined. Saw potential in theory of evolution for planned
human development (betterment).
Binet & Simon: developed 1st IQ tests to measure student abilities for education
purposes – determine which children would make the most out of education
eliminating factors such as personality differences and social class differences giving
equal. Opportunity for them to perform well and get a good education.
Lewis Terman and Maud Merrill
o Devised the Stanford-Binet scale
o Studied a sample of ‘gifted’ children throughout their lives – IQ of about 140
(longitudinal study)
o Highly intelligent individuals not weaklings and misfits but healthy and stable
Lewis Terman
o Military use (Alpha, Beta test) to assign soldiers to tasks appropriate to their
abilities during WW1
o Eugenics: promote selective breeding to cultivate desirable characteristics
(intellectually and physically)
Cyril Burt
o Advised the British government to use aptitude tests to determine which
children will go on to grammar schools (11+)
o His research on intelligence seemed to suggest that occupational levels and
social class are determined by innate and heredity levels of intelligence.
o Problems with data and analysis – fabricated?
Dark history of intelligence
Other issues
o Cultural bias in test construction and standardization procedures
o Intelligence tests favour groups from more affluent backgrounds and
discriminate against less privileged racial, ethnic or social groups.
Non-verbal IQ test e.g. Raven’s Progressive Matrices
More recent IQ tests
WISC (Wechsler Intelligence Scale for Children)
WASI (Wechsler Adult Scale for Intelligence)
Include verbal and non-verbal tests (tap into both crystalised and fluid intelligence)
, Basic concepts
Genotype = genetic makeup of an organism
Phenotype = observable physical properties of an organism; these include organisms’
appearance, development, and behaviour. Phenotype includes both genotype and
environmental influences
We can only measure phenotype. Performance depends on many factors.
Degrees of genetic relatedness = looking at people with various degrees of
relatedness can give us an understanding of the genetic basis of a concept. E.g.
identical twins share 100% of genetic makeup compared to siblings (50%) and
compare these to find out how much of the performance is genetically determined.
Atheoretical definition of intelligence = intelligence is what IQ tests measure. No
theory of intelligence that will determine what questions should be included in an IQ
test.
However: IQ tests highly correlate with each other and with other measures (e.g.
WM, Academic performance, problem solving, reasoning, career and income)
Correlation = statistical test and term that examines the relationship between 2 or
more variables.
Part 2
Is intelligence a single construct?
Generalised intelligence
o Single construct that influences all our cognitive functioning
o Demonstrated through correlations of performances on different tests
o Measures include
Stanford – Binet
Raven’s progressive matrices
Or is intelligence a multiple construct?
Composed of fluid and crystalised intelligence (Catell, 1987)
o Fluid intelligence – cog. Functioning component not influenced by the
environment, fixed throughout lifetime
o Crystalised intelligence – stored factual information, benefits from schooling
can change throughout life span
Supported by correlations between tests of FI. and CI. Respectively
Both interact in some ways
Relatively stable FI. But increasing CI. across life span
Is intelligence determined by genes or the environment?
Twin studies – valuable to examine genetic characteristics. However hard to separate
genetics and environmental factors in IQ test performance
