Punyawish Patumhirunruksa¹ (), Viola Stoermer³, Chaipat Chunharas^1,2; ¹Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand, ²King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand, ³Dartmouth College

Feature-based attention is an ability used to search for target features among distractors in an environment. Previous research has shown that older adults show deficits in feature-based attention compared to younger adults, in particular when it comes to ignoring distractors. However, these age-related declines appear to depend on how feature-based attention is engaged. Here we tested how proactive attentional control is affected by age. Two groups of participants (10 younger and 10 older adults, >60 years) performed a visual search task in which a ‘to-be-attended’ or ‘to-be-ignored’ cue indicated the likely target or distractor color with 80% probability at the beginning of each block. Following the cue, participants were instructed to search for a ring with a horizontal gap among distractors with vertical gaps. To assess whether the cues would modulate the saliency of the cued color proactively, on a subset of trials, participants performed a probe-color detection task in which they were presented with a probe that could either match the cued color or not. Our results showed that both groups' response times during the search were faster for valid target cueing (young: 795ms vs 926ms for targets, old: 1782 vs. 2244ms) and invalid distractor cueing trials (young: 828ms vs 807ms for targets, old: 1930 vs 1874ms) Interestingly, for the probe task, both groups' accuracy was higher when the probe appeared in the cued color relative to a neutral gray or the uncued color in both target and distractor cueing conditions. This indicates that older and younger adults initially enhanced the cued color regardless of whether it predicted the target or distractor, suggesting that they relied on reactive mechanisms to ignore the anticipated distractor color.