Normative adult age-related decrements are well documented for many diverse forms of effortful cognitive processing. However, it is currently unclear whether each of these decrements reflects a distinct and independent developmental phenomenon, or, in part, a more global phenomenon. A number of studies have recently been published that show…

A sample of 144 children from nursery school, first, and third grades were given a series of problems in which they were required to judge which of 2 synchronous events was longer in duration and to rationalize their judgments. (Author/JMB)

This paper reports two experimental studies of the development of time, speed and distance concepts in children. In Experiment I subjects (12 in each of four age groups: 5-, 8-, 11-year-olds, and adults) were asked to judge which of two electric trains on parallel tracks went faster, for the longer distance, or for more time. Subject's knowledge…