Aging and negative priming in a location suppression task: the long and the short of it

The role of temporal parameters in aging and inhibitory function was examined using negative priming (NP) and repetition priming (RP) in a task involving a series of visually presented prime-probe sets; responses were made on the basis of the location of a target stimulus. Preparatory intervals (PI) preceding prime-probe sets were 3,000 ms or 1,500 ms. The longer PI resulted in less NP in older adults than did the shorter PI. Further analysis suggest that older adults may be less prepared to inhibit the distractor following the longer PI. The longer PI also produced more RP than did the shorter PI for both age groups, indicating a greater emphasis on facilitatory processes in this condition. In addition, evidence was obtained to suggest that an inverse relationship between NP and RP exists for both young and old adults. These data suggest that individuals or task conditions may emphasize either facilitation or inhibition in selection.