The classification behavior of male and female college students was compared with that of healthy, well-educated older males and females. On the whole, the results failed to confirm other published evidence maintaining that aging is marked by conceptual deficits or a regressed mode of cognitive functioning. (Author/CS)

A broad literature review revealed that younger children are more likely to categorize objects along complimentary dimensions than older children who tend to categorize according to similarity. This developmental change is discussed in terms of etiology--internal organismic changes or environmental changes. (DP)

Formal and familiar materials were used to test Piagetian classification and formal operational abilities in two groups of educated adults: one group aged 30-38 and the other aged 57-82 years. Subjects did not show mastery of the tasks. Results suggest a new model of cognitive lifespan development. (Author/MS)

Examination of the way in which children conceive the development of animals shows that there are parallels among concepts of development with those of the periods of concrete operations and formal operations. The conception of development seems to advance further in the subsequent period of dialectical thought. (MS)