Attentional capture and aging: Implications for visual search performance and oculomotor control

Two studies examined potential age-related differences in attentional captu re. Subjects were instructed to move their eyes as quickly as possible to a color singleton target and to identify a small letter located inside it. O n half the trials, a new stimulus (i.e., a sudden onset) appeared simultane ously with the presentation of the color singleton target. The onset was al ways a task-irrelevant distractor. Response times were lengthened, for both young and old adults, whenever an onset distracter appeared, despite the f act that subjects reported being unaware of the appearance of the abrupt on set. Eye scan strategies were also disrupted by the appearance of the onset distracters. On about 40% of the trials on which an onset appeared, subjec ts made an eye movement to the task-irrelevant onset before moving their ey es to the target. Fixations close to the onset were brief, suggesting paral lel programming of a reflexive eye movement to the onset and goal-directed eye movement to the target. Results are discussed in terms of age-related s paring of the attentional and oculomotor processes that underlie attentiona l capture.