Age-related differences in saccadic indices of top-down guidance via short-term memory during visual search.

Abstract

Aging has been associated with significant declines in the speed and accuracy of visual search. These effects have been attributed partly to low-level (bottom-up) factors including reductions in sensory acuity and general processing speed. Aging is also associated with changes in top-down attentional control, but the impact of these on search is less well-understood. The present study investigated age-related differences in top-down attentional control by comparing the speed and accuracy of saccadic sampling in the presence and absence of top-down information about target color in young (YA) and older (OA) observers. Displays contained an equal number of red and blue Landholt stimuli. Targets were distinguished from distractors by a unique orientation, and observers reported the direction of the target's gap on each trial. Single-target cues signaled the color of the target with 100% validity. Dual-target cues indicated the target could be present in either colored subgroup. The results revealed reliable group differences in the benefits associated with top-down information on single-target cues compared to dual-target cues. On single-target searches, OA made significantly more saccades than YA to stimuli in the uncued color subset. Single-target cues also produced a smaller advantage in the time taken to fixate the target in OA compared to YA. These results support an age-related decline in observers' use of top-down information to restrict sequences of saccades to a task-relevant subset of objects during visual search. (PsycInfo Database Record (c) 2024 APA, all rights reserved).