Endogenous visuospatial precuing effects as a function of age and task demands.

This experiment examined the effects of age on processing resource capacity using an endogenous visuospatial precuing task and four levels of resource demands. Younger and older adults made speeded two-choice responses to dim and bright targets that required a line-orientation or a lexical decision. An arrow preceding target onset served as an attentional cue to affect the spatial distribution of resources. It provided accurate information about the target's location on most trials and inaccurate or neutral information on the remaining trials. Although older adults were slower than younger adults under all conditions and were more affected by the resource demand manipulations, they exhibited a pattern of precuing effects across conditions that was similar to that of the younger adults. Results are consistent with the idea that the visuospatial attention system remains relatively unaffected by aging. However, the data speak against the idea that capacity reduction is the primary contributor to age-related slowing.