Primary mental abilities

1
Primary mental abilities

• Verbal comprehension
• Word fluency
• Number facility
• Spatial orientation
• Associative memory
• Perceptual speed
• Reasoning

2
SLS Cross-sectional data
3
SLS Longitudinal data
4
SLS Cohort differences
5
Conclusions from SLS

• Cross-sectional age differences vary with
  ability and time of measurement earliest
  decrements in mid-40s
• Cohort generational trends vary with ability
  range from positive to negative-convex
• Longitudinal age changes vary with ability
  earliest decrements in mid-60s to 70s

6
Crystallized intelligence

• Crystallized intelligence is the accumulated
  knowledge of an individual or the incorporation
  of the intelligence of a culture.
• Test example 1 - Comprehension Why is a free
  press important in a democracy?
• Test example 2 - Number problems A TV that
  normally sells for 800 is reduced by 15. What
  is its reduced price?

7
Fluid intelligence

• Fluid intelligence is the ability to discover new
  relations or rules it is related to
  neurophysiological health.
• Test example 1 - Number series 1 3 8 19
  42 ?
• Test example 2 - Frames classification What
  makes these frames look the same?

0 0 1 0
X 0 1
0 X 1 X
8
Everyday problem-solving
From Cornelius Capsi, 1987. Everyday problem
solving in adulthood and old age. Textbook p. 331
9
What influences intellectual change?

• Health/terminal drop
• Speed of processing
• Lifestyle (Use it or lose it)
• Societal IQ gains

10
Wechsler Intelligence Scale

• Verbal Scale
• Information
• Comprehension
• Arithmetic
• Similarities
• Digit span
• Vocabulary

• Performance Scale
• Digit symbol substitution
• Picture completion
• Block design
• Picture arrangement
• Object assembly
• Matrix reasoning

11
What is an IQ?

• IQ/scaled score is computed as distance from the
  mean (100/10) of the reference group
• Raw scores required for mean IQ vary by age 10
  on Digit Symbol requires 82 pts for 20-24 y-olds,
  37 pts for 85-89 y-olds
• Raw scores required for mean IQ also vary by
  generation (Flynn effect)

12
The Flynn Effect
13
Gains on Matrices in 5 countries
14
IQ gains and test type