Aging and the locus of the global precedence effect: a short review and new empirical data.

Precedence of the global over the local level in visual perception is well established by the use of compound, or hierarchical, stimuli. However, (a) virtually nothing is known concerning the fate of global precedence with normal aging, and (b) there is still a debate about the early versus late perceptual locus of the effect. The present study was planned to investigate both topics. Two experiments are reported where young adult and elderly subjects were enrolled for the recognition of compound letters either at the global or at the local level. In order to recruit late perceptual processes, the case of the letters varied in such a way that subjects had to activate graphemic codes to take their decision. It appeared that the global precedence effect was preserved. This observation shows an early perceptual source of the global precedence effect, which is then transferred to later stages of information processing. Age did not affect the global precedence phenomenon.