"Perceptual Speed" and Cognitive Controls

Derived from cognitive psychology, a theoretical approach to group test construction resulted in the production of simple cognitive tasks suitable for use with literate subjects. Group performance was modified by the encoding demands of different stimulus properties. Performance was also affected by giving instructions to subjects that altered deep structure attentional controls on encoding propositions about the stimuli. Individual differences in performance on the tasks were substantial. The model for individual and group performance is additive, and it appears robust within individuals as well as across groups representing "idealized" individuals. Confirmatory replications were obtained across cultures, developmental stages, in long- and short-term work periods, and across symbol types. These are summarized. In the discussion the authors conclude that cognitive theory must be the basis for future test development. They assert, finally, that comparative assessment of cognitive functions within or across cultures cannot proceed until tests and scores derived from them are capable of construct validation outside the scope of traditional psychometric methods.