Perception of multidimensional stimuli: a differential-sensitivity account of cognitive processing and development.

A differential-sensitivity account of cognitive processing is described that emphasizes the development of perceptual sensitivity to object relations that are directly perceived. Four experiments are presented that investigate this account and compare it to the integrality-separability view of development and the view that younger children are nonselective in their processing of multidimensional stimuli. Results show that stimulus differences are more salient than identities (Expt. 1), younger as well as older children are highly selective in their perception and classify stimuli by separate dimensions (Expt. 2), differential sensitivity affects the perceived magnitude of stimulus differences (Expt. 3), and younger and older children perceive separate dimensions in speeded classifications (Expt. 4). The importance of considering individual patterns of responses in cognitive and developmental research is also demonstrated.