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Intelligence—Why It Grows, Why it declines

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John L. Horn is associate professor of psychology at the University of Denver. His research interests are human abilities and motives and the study of the dynamics and patterns in the expression of alcoholic symptoms. He wrote (with R. B. Cattell) the handbook for the Motivational Analysis Test.

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Horn, J.L. Intelligence—Why It Grows, Why it declines. Trans-action 5, 23–31 (1967).

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  • Physiological Base
  • Memory Span
  • Intellectual Performance
  • Intelligence Test
  • Fluid Intelligence