By
Mark Piazza
Sibley Bardales
Stephanie Townley
Phase 1: Cross-Sectional
Evidence for Intellectual Decline
Phase 2:Longitudinal Evidence
for Intellectual Stability
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Longitudinal study: research in which the
same people are restudied or retested over a
long period
Several psychologists studied intelligence
longitudinally to entering college students in
1920
They found that their intelligence remained
stable until late in life
The problem with cross sectional studies was
that it compared 70 year olds and 30 year olds
who are from a different era, different sized
families, and better or less affluent families
Phase 3: It All Depends
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Intellectual performance an increase or decrease
depending on how we assess it.
Research has found that intelligence isn’t a single
trait but distinct skills and abilities.
Intellectual performance increases or decreases with
age depending on what you measure.
Crystallized intelligence is one’s accumulated
knowledge as reflected in vocabulary and analogies
tests - it increases with age.
Fluid intelligence is ones ability to reason speedily
and abstractly, as when solving logic problems –
decreases with age.
Fun fact - having social contacts has shown to
decrease the onset of Alzheimers.