[Development of intelligence in old age]

This article attempts to find the structure of a selected spectrum of intelligence. A combination of longitudinal and cross-sectional methods is applied. Two dimensions were found, which can be named as "crystallized" and "fluid" abilities (in the sense of Horn & Cattell). Whereas, the crystallized abilities do not show any systematic variation from age 61 to 83, fluid abilities decline with age. Schaie's three-component-model is not able to describe differences and variations of crystallized intelligence. Within fluid intelligence, age changes are more important than cohort differences. There are hints that structural changes take place.