A Global Developmental Trend in Cognitive Processing Speed

Children respond more slowly than young adults on a variety of information‐processing tasks. The global trend hypothesis posits that processing speed changes as a function of age, and that all component processes change at the same rate. A unique prediction of this hypothesis is that the overall response latencies of children of a particular age should be predictable from the latencies of young adults performing the same tasks—without regard to the specific componential makeup of the task. The current effort tested this prediction by examining the performance of 4 age groups (10‐, 12‐, 15‐, and 19‐year‐olds) on 4 different tasks (choice reaction time, letter matching, mental rotation, and abstract matching). An analysis that simultaneously examined performance on all 4 tasks provided strong support for the global trend hypothesis. By plotting each child group's performance on all 4 tasks as a function of the young adult group's performance in the corresponding task conditions, precise linear functions were revealed: 10‐year‐olds were approximately 1.8 times slower than young adults on all tasks, and 12‐year‐olds were approximately 1.5 times slower, whereas 15‐year‐olds appeared to process information as fast as young adults.