Unit 11: Testing and Individual Differences

What is Intelligence?

Intelligence mental quality consisting of the ability to learn from experience, solve problems, and use knowledge to adapt to new situations.

Meanings can vary from culture to culture.

How might the North American culture asses or define intelligence as compared to other cultures around the world? DISCUSS

HINT: Use the picture of the traditional folk healer as a starting off point.

Is intelligence one aptitude or many? Based on cognitive speed or neurologically measurable? Easiest way to think about it, is that intelligence is a ‘concept’ not a ‘thing’. Therefore it is interpretable on many levels.

So, when intelligence is measured by IQ (Intelligence Quotient), as if it is a fixed trait (like height) a reasoning error occurs, called reification – viewing an abstract, immaterial concept, as if it were a concrete thing.

Using an intelligence test ( a method of assessing an individual's mental aptitudes and comparing them with those of others, using numerical scores), simply places a person along a scale as compared with others scores.

Street smarts vs. Book smarts.

Is Intelligence One General Ability or Several Specific Abilities?

Can you think of someone who is great at science but has a hard time with math? Someone who may be amazing at math, but can’t hold their own in a literary discussion. Are these people still intelligent? Can you rate them only on a single scale?

General Intelligence a general intelligence factor that, according to Spearman and others, underlies specific mental abilities and is therefore measured by every task on an intelligence test. By Charles Spearman,

Usually just called ‘G’…. Not like the original G… just G. What at title to have ! It’s like Madonna!

Spearman developed factor analysis a general intelligence factor that, according to Spearman and others, underlies specific mental abilities and is therefore measured by every task on an intelligence test.

L.L. Thurstone tried to counter the G theory. When Spearman tested people, he noticed that if they scored high in one category, they tended to score high in other categories as well. Thurstone did a series of tests to counter this. His results? Same as Spearman. Therefore it is commonly accepted that general intelligence is correct.

g

How to organize or theorize general intelligence? Think of an athlete. If you are good at long distance running, it may not mean your are good at powerlifting. However, if you are in overall, good athletic shape, you will probably be good at a larger variety of sports than a person who is out of shape.

Theories of Multiple Intelligences

Since the G classification, psychologists have been trying see how intelligences may interact.

Think of savant syndrome ( a condition in which a person otherwise limited in mental ability has an exceptional specific skill, such as in computation or drawing), where the individual typically scores low on an intelligence test but have an island of brilliance somewhere else.) There is more than one way to be ‘smart’.

Savant Syndrome

Is Intelligence One General Ability or Several Specific Abilities?

Theories of Multiple Intelligences

Gardner’s Eight Intelligences Linguistic Logical-mathematical Musical Spatial Bodily-kinesthetic Intrapersonal Interpersonal Naturalist

Is Intelligence One General Ability or Several Specific Abilities?

Theories of Multiple Intelligences

Is Intelligence One General Ability or Several Specific Abilities?

Theories of Multiple Intelligences Sternberg’s Three Intelligences

Analytical (academic problem-solving intelligence –assessed using intelligence tests. Predicts school grades well and not as well with vocational success.

Creating intelligence – reacting adaptably to novel situations and generating novel ideas.

Practical intelligence – everyday tasks that may be ill defined with multiple solutions. Seen most in business

Comparing Theories of Intelligence

What Makes Up Emotional Intelligence? Distinct from academic intelligence is social intelligence – the know-how involved in comprehending social

situations and managing oneself successfully.

A part of social intelligence is emotional intelligence the ability to perceive, understand, manage, and use emotions.

Emotional intelligence should not include varied traits such as self-esteem and optimism

Perceive emotions – to recognize them in faces, music, and stories.

Understand emotions – to predict them and how they change and blend.

Manage emotions – to know how to express them in varied situations.

Use emotions for adaptive or creative thinking

Is Intelligence Neurologically Measurable?Brain Size and Complexity

Fun fact! English Poet Lord Byron had a 5 pound brain, 2 pounds bigger than the normal size!

Fun fact! Beethoven's brain had exceptionally numerous and deep convolutions.

Fun fact! Einstein had a 15% larger lower parietal lobe – centre for mathematical processing and spatial information. However, other regions seem to register a bit smaller. May be why our most notable mathematicians were late bloomers (slow to talk, etc).

Fun fact! More educated people die with more synapses than uneducated people. Did they seek education because they had more synapses or have more synapses because of their education?

Unfortunately brain structure and size does not equal intelligence. Could it be genetics? Environment? (rats in stimulating environments) Nutrition?

Neural plasticity may be the biggest link we have. The more mouldable the brain, the more opportunity for new learning. Agile minds = agile brains.

Type of brain matter also may play a role – Grey Matter (neural cell bodies) VS White Matter (axons and dendrites) More grey matter in memory, attention and language areas– higher intelligence scores.

Is Intelligence Neurologically Measurable?Brain Function

When people think about the questions on common intelligence tests, a frontal lobe area just above the outer edge of the eyebrows becomes especially active – left side for verbal questions and on both sides for spatial questions.

Perceptual Speed – Intelligence and perceptual speed are closely correlated. Experiment – stimulus picture flashed first, then masking image to override the stimulus picture. Then asked if the right or left side was longer. The length of time the stimulus is flashed is varied but people with higher intelligence scores can tell which side is longer, with less time.

Neurological Speed – Neural speeds on simple tasks (pressing a button) have been found to be faster in people who score higher on intelligence tests.

Assessing Intelligence

Origins of Intelligence Testing

Intelligence testing stemmed from understanding individual differences and seeing where some people may exceed over others. Ex. What job are you best suited for?

English scientist Francis Galton had a fascination with measuring human traits. When his cousin CHARLES DARWIN (Hello! Best family connection EVER!) proposed the idea that nature chooses successful traits through natural selection, Galton wondered if it was possible to measure natural ability and encourage those of higher ability to mate.

Galton measured 10,000 people at the 1884 London Exposition on the following traits: Reaction Time

Sensory Acuity

Muscular Power

Body Proportions

What did he learn? Nothing. The measure did not correlate. There was no distinctive difference between intelligent and average people.

Alfred Binet: Predicting School Achievement

Intelligence testing became more modern, when at the turn of the century, France passed a law that all children need to go to school.

This inevitably saw that some students were in need of different programing separate from the ‘typical’ school experience.

Did not want the teachers to assess, because of bias. French government hired Binet to tackle the problem.

Came up with the idea of mental age a measure of intelligence test performance devised by Binet; the chronological age that most typically corresponds to a given level of performance. Thus, a child who does as well as the average 8-year-old is said to have a mental age of 8.

Different from chronological age.

Binet’s goal was simply to identify students who required special attention. Did not identify the ‘why’ but Binet speculated that it had to do with environment. He also worried that his test would used to label children and limit their opportunities.

Lewis Terman: The Innate IQ

Terman adapted the Binet test to expand beyond children and into the teenage/adult years. Called it the Stanford-Binet Test the widely used American revision (by Terman at Stanford University) of Binet’s original intelligence test.

From these tests, we got the famous IQ (intelligence quotient) test defined originally as the ratio of mental age (ma) to chronological age (ca) multiplied by 100 (thus, IQ=ma/ca X 100). On contemporary intelligence tests, the average performance for a given age is assigned a score of 100.

For example, a child who has the same mental and chronological age, would have an IQ of 100. But an 8 year old who answers questions like a 10 year old would have an IQ of 125.

This original test worked well for children, but not adults. Most modern IQ tests (although not measuring IQ) represent the test takes performance relative to the aver performance of others the same age. Average IQ? Between 85 and 115.

Used in WW1 to asses army recruits and immigrants to the US. Results showed bias towards those with Anglo-Saxon heritage and reduced quotas of those immigrating from Southern and Eastern Europe.

Terman believed that IQ testing would ‘ultimately result in curtailing the reproduction of feeble mindedness and in the elimination of an enormous amount of crime, pauperism (poverty) and industrial inefficiency.’ Eugenics? DISCUSS!

IQ Test? TO THE LAPTOPS!

http://www.free-iqtest.net/

Modern Tests of Mental Abilities

Tests are divided into 2 categories:

1) Achievement Tests tests designed to assess what a person has learned.

Ex) Final AP Exam

2) Aptitude Tests tests designed to predict a person’s future performance; aptitude is the capacity to learn.

Ex) College Entrance Exam

Most widely used intelligence test is the Wechsler Adult Intelligence Scale (WAIS) the WAIS is the most widely used intelligence test; contains verbal and performance (nonverbal) subtests. WISC is for children and has variants for each age group. (see picture)

Measures not only overall intelligence score, but separate scores for verbal comprehension, perceptual organization, working memory and processing speed.

Provides clues to cognitive strengths and weaknesses that teachers/therapists can use to work upon. Ex. Low language or verbal score combined with high scores in other areas can indicate a reading/language disability.

Wechler Adult Intelligence Scale

To the Laptops! WAIS Time!

http://wechsleradultintelligencescale.com/

Similarities and differences between IQ and WAIS tests? DISCUSS!

Principles of Test Construction

The number of questions you answer correctly on an intelligence test will tell us almost nothing. How those answers are compare with others performance will tell us what we need to know.

In order to find comparisons, the tests need to be given to a representative sample of people. Called standardization defining meaningful scores by comparison with the performance of a pretested group.

Group scores are then distributed on a normal curve a symmetrical, bell-shaped curve that describes the distribution of many physical and psychological attributes. Most scores fall near the average, and fewer and fewer scores lie near the extremes.

Normal Curve

Flynn Effect

Intelligence scores have been improving over time. Higher scores seen now than before.

Better testing? Better nutrition? More education? More stimulating environments? Less childhood disease? Smaller families? More parental investment?

Reliability

Tests need to have Reliability the extent to which a test yields consistent results, as assessed by the consistency of scores on two halves of the test, or on retesting.

In order to check results, researchers retest people. May take the same test, or split the test in half (evens vs odds) to see if they agree.

If they do, the test is reliable.

Most modern tests (ex. WISC) have a reliabilities of about +.9, very high.

Validity

High reliability does not ensure a test validity the extent to which a test measures or predicts what it is supposed to.

Ex. If you used an inaccurate tape measure to measure peoples heights, your test would have a high reliability but a low validity.

2 Types:

1) Content Validity the extent to which a test samples the behavior that is of interest.

Ex) A drivers road test has content validity because it samples tasks the driver routinely faces.

2) Predictive Validity the success with which a test predicts the behavior it is designed to predict; it is assessed by computing the correlation between test scores and the criterion behavior (also called criterion-related validity).

Ex) That a final exam should predict the criterion of future performance.

The Dynamics of Intelligence

Stability or Change?

Are intelligence scores stable throughout life?

By age 4, scores on IQ tests seem to predict scores later on in adult life.

IQ scores stabilize by age 7.

Extremes of Intelligence – Low Extreme

Intellectual Disability (formerly referred to as mental retardation) a condition of limited mental ability, indicated by an intelligence score of 70 or below and difficulty in adapting to the demands of life; varies from mild to profound.

1% of NA population meets this criteria, with males outnumbering females by 50%.

Some may have a physical cause, such as Down’s Syndrome a condition of intellectual disability and associated physical disorders caused by an extra copy of chromosome 21.

Historically, raised at home, died young or worked in labor jobs, such as farming.

Last ½ of 20th century, swung to normalization.

Ex. Mainstreamed into classrooms, live at home, not allowed to execute for crimes in US – cruel and unusual punishment designation.

Extremes of IntelligenceClassifications of Intellectual Disability

Level Approximate

Intelligence Scores

Adaptation to Demands of Life

Mild 50-70 May learn academic skills up to sixth-grade level. Adults may with assistance, achieve self-supporting social and vocational skills

Moderate

35-50 May progress to second-grade level academically. Adults may contribute to their own support by laboring in sheltered workshops

Severe 20-35 May learn to talk and to perform simple tasks under close supervision but are generally unable to profit from vocational training

Profound

Below 25 Require constant aid and supervision

Extremes of Intelligence – High Extreme

Extremes of Intelligence – High Extreme

Terman’s study of gifted children – scored over 135 on IQ test. Followed over the next 70 years. High number of lawyers, doctors, professors, scientists and writers.

Self-fulfilling prophecy – those labelled ‘ungifted’ may be influenced to become so by denying them opportunities for enriched education.

Tracking students – placing them in groups based on intelligence. Examples?

Appropriate developmental placement – placed in programs where they excel. Ex. Good at math, art, social leadership, etc.

Genetic and Environmental Influences on Intelligence

Intelligence runs in families but is also dependent on the environment. Identical twin studies – twins reared together have the same IQ test

numbers of someone who takes the test twice. Fraternal are less. Brain scans reveal that identical twins have the same amount of grey

matter and their brains are the same in areas associated with verbal and spatial intelligence.

Polygenetic – genes for intelligence have been found on chromosomes. Adoptive children studies – during childhood, adoptive children in the

same family tend to have similar scores – supports the environment argument. However, as they become adults, the discrepancy between parents and adoptive children grows.

Heritability

Environmental Influences

Early environmental influences Tutored human enrichment – neglect in orphanages lead

to programs where adults rehabilitate babies by teaching them language and basic skills.

Targeted training - an enriched environment while in infancy will not give babies a head start. Learn when you learn!

Schooling and intelligence – best practices Project Head Start – quality, funded preschool programs.

Group Differences in Intelligence Test ScoresGender Similarities and Differences

Spelling – females better spellers Verbal ability – females have better verbal fluency and remembering

words. Nonverbal ability – females are better at remembering and locating

objects/picture associations. Sensation – females more sensitive to touch, taste and smell. Emotion-detecting ability – females better. Math and spatial aptitudes – same between 2 genders, but males

better at problem solving, females in computation. Greater male variability – IQ scores vary more in males than in

female.

Group Differences in Intelligence Test ScoresEthnic Similarities and Differences

Ethnic similaritiesEthnic differencesBoils down to – ‘Grass grows

where you water it’.

The Question of Bias

Two meanings of bias Popular sense – intelligence tests are bias. Middle class

assumptions – cup goes with saucer, insurance is bought to protect the home. May not be the same in all classes.

Scientific sense – hinges on test’s validity. Test-taker’s expectations – Will I do well or not? Stereotype threat a self-confirming concern that one

will be evaluated based on a negative stereotype.

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