Intelligence (Chapter 9, p. 324-335)

Lecture Outline:History of intelligence

IQ and normal distributions

Measurement and Theory

Two Views of Intelligence

Psychophysical RT, sensitivity to

physical stimuli Galton (1883) and later

Cattell (1890) proposed psychophysical tests measured ability

Contribution: Psychometrics, measurement of traits and processes

Mental judgement Memory, vocabulary,

and perceptual discrimination

Binet & Simon (1904) diagnosed “mental defectives” in Paris

Contribution: Testing and IQ

Definition of Intelligence

An inferred characteristic usually defined as the ability to profit from experience, acquire knowledge, think abstractly, act purposely, and adapt to changes in the environment.

What is an Intelligence Quotient?

IQ = (MA / CA) X 100 MA = Mental age, CA = Chronological age 8 year old with MA of 12 has IQ of 150 Problem across life span. MA may not differ

much from age 25 to 50, but IQ of someone 50 is not half that of a 25 year old

Problem with different variability at each age

Intelligence tests and IQ

Goal directed adaptive behavior IQ tests define a domain of skills

necessary to succeed in school

What is the goal?

What is the goal?

What is the environment being adapted to?

Original Purpose: Identify “slow learners” and bring them up to speed

Measuring intelligence

Assessing intelligence

Stanford Binet- Revised: Short-term memory, Verbal, Quantitative, and

Figural Abstract Reasoning

Wechsler Scales: Verbal, Performance, and Total IQ scores WAIS-III, WISC-III, WPPSI Most commonly used intelligence test today

Interpretation of performance

Standardized testing conditions: we assume that temperature, lighting, vision, hearing does not impact performance

Lack of motivation and performance anxiety can detract from performance– If you think you will fail or are stressed out, performance

decreases– Mastery, positive stereotypes, confidence enhances

performance Low motivation interferes with high IQ Right answer (psychometric) and strategies used

when solving problems (cognitive)

Potential for cultural bias in IQ tests What is The

Bluenose?

Who was Thomas Jefferson?

Validity: Example of SAT

Face validity: Does the test make sense? Predictive validity: Does it predict Acadia

grades? Concurrent validity: Were they related to

Grade 12 grades? Construct validity: Does the SAT measure

the construct it is supposed to measure?

Definitions

Aptitude: Ability to learn in a specific area

Achievement: What is already learned in an area

Psychometric: Psychological measurement

Metacognition: Understanding and control of thought processes

Spearman’s Model

Multiple intelligences?

Spatial in athletes, mechanics

Musical genious

Emotional intelligence and empathy

Triarchic Theory of Intelligence

Transferring skills to new situations

e.g., setting up a DVD player

Componential

Information-processing strategies, metacognition

e.g., long division

Experiential

Contextual Practical applications of intelligence, knowing when to change, adapt, or fix your environment

e.g., getting to Halifax

Normal curve of IQ scores

Extremes of intelligence

Mental Retardation is at low end

Dx when IQ and adaptive behavior is low

Mild 50-70 Moderate 35-55 Severe 20-40 Profound <25

Gifted at high end 1% have IQ > 135 Terman’s longitudinal

study documenting “success” of men with IQ >140, but those with low motivation underachieved

School programming Mensa: IQ 130 or 98th

percentile